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Leaf litter microbes collectively degrade plant polysaccharides, influencing land-atmosphere carbon exchange. An open question is how substrate complexity-defined as the structure of the saccharide and the amount of external processing by extracellular enzymes-influences species interactions. We tested the hypothesis that monosaccharides (i.e. xylose) promote negative interactions through resource competition, and polysaccharides (i.e. xylan) promote neutral or positive interactions through resource partitioning or synergism among extracellular enzymes. We assembled a three-species community of leaf litter-degrading bacteria isolated from a grassland site in Southern California. In the polysaccharide xylan, pairs of species stably coexisted and grew equally in coculture and in monoculture. Conversely, in the monosaccharide xylose, competitive exclusion and negative interactions prevailed. These pairwise dynamics remained consistent in a three-species community: all three species coexisted in xylan, while only two species coexisted in xylose, with one species capable of using peptone. A mathematical model showed that in xylose these dynamics could be explained by resource competition. Instead, the model could not predict the coexistence patterns in xylan, suggesting other interactions exist during biopolymer degradation. Overall, our study shows that substrate complexity influences species interactions and patterns of coexistence in a synthetic microbial community of leaf litter degraders.

Animal waste can contribute substantially to nutrient cycling and ecosystem productivity in many environments. However, little is known of the biogeochemical impact of animal excretion in wetland habitats. Here we investigate the effects of wood frog (Lithobates sylvaticus) tadpole aggregations on nutrient recycling, microbial metabolism and carbon cycling in geographically isolated wetlands. We used a paired mesocosm and field study approach that utilized measurements of tadpole excretion rates, microbial extracellular enzyme activities, and litter degradation. We found a strong relationship between tadpole development and nutrient excretion, demonstrating that ontological changes impact tadpole‐mediated nutrient cycling in wetland habitats. Further, the interplay between population‐level tadpole excretion and wetland hydrologic conditions increased ambient NH4+$$ {\mathrm{NH}}_4^{+} $$ and PO43−$$ {\mathrm{PO}}_4^{3-} $$ concentrations by 56 and 14 times, respectively, compared to adjacent wetlands without tadpoles. Within our mesocosm study, microbes decreased extracellular enzyme production associated with nitrogen acquisition in response to the presence of tadpole‐derived nitrogen. In addition to microbial metabolic responses, tadpole presence enhanced litter breakdown in both mesocosms and wetlands by 7% and 12%, respectively, in comparison to reference conditions. These results provide evidence for the functional and biogeochemical role of tadpole aggregations in wetland habitats, with important implications for ecosystem processes, biodiversity conservation, and ecosystem management. [ABSTRACT FROM AUTHOR]

Saline shallow lakes in arid and semi-arid regions frequently undergo drying episodes, leading to significant variations in salinity and water availability. Research on the impacts of salinity and drought on the structure and function of biofilms in hypersaline shallow lakes is limited. This study aimed to understand the potential changes of biofilms in playa-lake sediments during the drying process. Sediments were sampled at different depths (surface, subsurface) and hydrological periods (wet, retraction, and dry), which included a decrease in water activity (aw, the availability of water for microbial use) from 0.99 to 0.72. aw reduction caused a greater effect on functional variables compared to structural variables, indicating the high resistance of the studied biofilms to changes in salinity and water availability. Respiration and hydrolytic extracellular enzyme activities exhibited higher values under high aw, while phenol oxidase activity and prokaryote biomass increased at lower aw. This shift occurred at both depths but was more pronounced at the surface, possibly due to the more extreme conditions (up to 0.7 aw). The increased levels of extracellular polymeric substances and carotenoids developed at low aw may help protect microorganisms in high salinity and drought environments. However, these harsh conditions may interfere with the activity of hydrolytic enzymes and their producers, while promoting the growth of resistant prokaryotes and their capacity to obtain C and N sources from recalcitrant compounds. The resilience of biofilms in hypersaline lakes under extreme conditions is given by their resistant biochemichal structure and the adaptability of their microbial functioning. [ABSTRACT FROM AUTHOR]

Epigenetics has emerged as a potent field of study for understanding the factors influencing the effectiveness of human disease treatments and for identifying alternations induced by pathogens in host plants. However, there has been a paucity of research on the epigenetic control of the proliferation and pathogenicity of fungal plant pathogens. Fungal plant pathogens such as Magnaporthe oryzae , a significant threat to global rice production, provide an important model for exploring how epigenetic mechanisms govern fungal proliferation and virulence. In M. oryzae , epigenetic alterations, such as DNA methylation, histone modification, and non-coding RNAs, regulate gene expression patterns that influence the pathogen's ability to infect its host. These modifications can enhance fungal adaptability, allowing the pathogen to survive in diverse environments and evade host immune responses. Our primary objective is to provide a comprehensive review of the existing epigenetic research on M. oryzae and shed light on how these changes influence the pathogen's lifecycle, its ability to invade host tissues, and the overall severity of the disease. We begin by examining the epigenetic alterations occurring in M. oryzae and their contributions to the virulence and proliferation of the fungus. To advance our understanding of epigenetic mechanisms in M. oryzae and similar plant diseases, we emphasize the need to address unanswered questions and explore future research directions. This information is crucial for developing new antifungal treatments that target epigenetic pathways, which could lead to improved disease management. [ABSTRACT FROM AUTHOR]

This study analysed basidiomycetous yeasts isolated from the phylloplane of crops and spontaneous plants in Italian agroecosystems. A total of 25 species belonging to 17 genera were recognized by analysing 83 isolates from vineyards and orchards, that are not treated with synthetic fungicides, and adjacent natural areas. Rhodotorula graminis and Filobasidium magnum were the most frequent species but 13 others were represented by a single isolate (e.g., Buckleyzyma salicina, Pseudozyma prolifica, and Moniliella megachiliensis). Preliminary analysis of (GTG)5-PCR fingerprinting revealed high genetic intraspecific heterogeneity. All isolates were characterized by their production of extracellular hydrolytic enzymes and their sensitivity to six commercial fungicides used in Italy. The isolates displayed great variability in these phenotypic traits, which play an important role in the survival of yeast populations in agroecosystems. Most of them exhibited lipolytic, proteolytic, β-glucosidase and pectinolytic activities, but only three (F. magnum, Kwoniella mangroviensis and Ps. prolifica) also had cellulolytic and amylolytic activity. Most isolates were sensitive to four fungicides, and one R. graminis isolate was resistant to all six. This heterogeneity was not related to the geographical origin of the isolates. The lack of selective factors (i.e. pesticide treatments) in the sampling fields and the presence of adjacent natural areas may have favored the maintenance of an elevated level of strain diversity. This study provides new information on phylloplane basidiomycetous yeasts in agroecosystems and opens the way to further investigations into the impact of agricultural practices on the microbial diversity of these natural habitats. [ABSTRACT FROM AUTHOR]

Edible and medicinal mushrooms possess excellent nutritional properties due to their incredible versatility in growing on different substrates and producing extracellular enzymes with a wide range of specificity. These features make them excellent candidates for various biotechnological applications. In this context, biotechnological applications using edible and medicinal mushrooms can focus on the bioprocessing of agro‐industrial wastes, an economical and environmentally friendly strategy. This review, based on recent original research and scientific reviews, highlights the versatility and potential of mushrooms in terms of sustainability and efficiency. We emphasized the biotechnological applications of edible and medicinal mushrooms and their enzymes including food production with high nutraceutical value by enhancing the quality and flavor of food industry products. Other biotechnological applications addressed in this review were cosmeceutical and biomedical development using mushroom extracts with bioactive compounds; wood pulp pretreatment processes in the pulp and paper industry; bioethanol production; and bioremediation for decontaminating soils and polluted effluents. These applications explain how edible and medicinal mushrooms have gained significance in biotechnology over the years, opening new avenues for innovation. The current tendency to study edible and medicinal mushrooms has gained the attention of researchers because these are still less known organisms becoming an attractive and natural source of novel bioactive compounds that could be integrated into a circular model production. [ABSTRACT FROM AUTHOR]

Comprehensive characterization of AML-associated T cells during disease progression is essential to identify relevant immune escape mechanisms and new immunotherapeutic approaches. Investigating the processes that lead to an immunosuppressive environment under progression of AML is difficult in humans, because by the time of diagnosis the disease is often progressed far beyond the initial stages. Therefore, to investigate T-cell phenotypes during progression a C57BL/6 mouse model was used. The CD3+ T cells were characterized by performing multiparametric flow analyses at different time points (day 0 = healthy mice, day 7, day 14, and day 21). The study revealed that the spleen is highly infiltrated by reg CD4+ T cells at day 21 of AML progression. These spleen-infiltrating reg CD4+ T cells mainly showed an effector memory differentiation with high expression and co-expression of the checkpoint molecules TIGIT, PD-1, OX40, and the two ectoenzymes CD39 and CD73. Substantial expression of the checkpoint molecules was restricted to the central memory and effector memory compartments. Furthermore, functional evaluation of TIGIT was performed. Blocking TIGIT resulted in a significantly increased lysis of C1498 AML cells in cocultures with AML-primed CD3+ T cells. Together these data confirm that the expression of the checkpoint receptor TIGIT is relevant for dysfunction of AML-associated T cells and, thus, represents a suitable target for future immunotherapeutic approaches. [ABSTRACT FROM AUTHOR]

Soil microbial extracellular enzymes play crucial roles in soil carbon and nutrient cycling by catalyzing soil biochemical processes. However, the activity and stoichiometry of enzymes involved in the carbon, nitrogen, and phosphorus cycles in the environment with the highest density of wild giant pandas on the southern slopes of the Qinling Mountains is unknown. We have established eight research areas at an elevation of 1090–2621 m. The β‐1,4‐glucosidase (BG), β‐1,4‐N‐acetylglucosaminidase (NAG), and acid phosphatase (APase) in soil samples were measured. We used redundancy analysis and structural equation model to evaluate the driving factors of metabolic restriction of soil microorganisms along the elevational gradient, and four models were used to cross‐evaluate the nutrient restriction status of soil microorganisms. The results showed that most soil physiochemical properties, soil microbial biomass, and microbial extracellular enzymes exhibited a hump‐shaped trend with increasing elevation. Elevation indirectly affected soil enzyme activity and stoichiometry by C, N, and P status. Microorganisms are limited by C at lower and higher elevations but limited by N at medium elevations. These results could help strengthen the conservation and management of the wild panda's natural habitat. Core Ideas: Soil nutrient and elevation change are the main influence factors of soil enzyme activity and stoichiometry.The soil microorganisms in the Foping Protected area are limited by P, limited by N at middle and high elevations.Soil microorganisms are less restricted by C in middle elevations than at other elevations.Soil microorganisms to maintain a stable elemental composition of biomass are weak in the southern slope of Qinling. [ABSTRACT FROM AUTHOR]

Wildfire is a disturbance expected to increase in frequency and severity, changes that may impact carbon (C) dynamics in the soil ecosystem. Fire changes the types of C sources available to soil microbes, increasing pyrogenic C and coarse downed wood, and if there is substantial tree mortality, decreasing C from root exudates and leaf litter. To investigate the impact of this shift in the composition of C resources on microbial processes driving C cycling, we examined microbial activity in soil sampled from an Oregon burn 1 year after fire from sites spanning a range in soil burn severity from unburned to highly burned. We found evidence that postfire rhizosphere priming loss may reduce soil C loss after fire. We measured the potential activity of C‐acquiring and nitrogen (N)‐acquiring extracellular enzymes and contextualized the microbial resource demand using measurements of mineralizable C and N. Subsurface mineralizable C and N were unaltered by fire and negatively correlated with hydrolytic extracellular enzyme activity (EEA) in unburned, but not burned sites. EEA was lower in burned sites by up to 46%, but only at depths below 5 cm, and with greater decreases in sites with high soil burn severity. These results are consistent with a subsurface mechanism driven by tree mortality. We infer that in sites with high tree mortality, subsurface EEAs decreased due to loss of rhizosphere priming and that inputs of dead roots contributed to mineralizable C stabilization. Core Ideas: Postfire extracellular enzyme activity decreases were observed only in sub‐soils of higher burn severity sites.In high tree mortality burns, loss of rhizosphere priming may slow decomposition and mitigate carbon loss.This work challenges conventional views that fire affects only the surface of soils via direct heat and combustion. Plain Language Summary: Wildfires are expected to become more severe and frequent, which may change how much carbon is stored in the soil. Fire changes the relative amount of leaves, wood, and charcoal available for soil microbes to decompose, which may affect soil microbial activity and soil carbon as a result. In this study, we evaluated the effect of fire on soil microbial decomposition activity. We found burned areas had less microbial decomposition activity than unburned areas, but only below soil depths of 5 cm in areas where most trees died after the fire. This was a surprising result because fire heat and combustion only directly affects the surface soil. We attribute the lower activity in higher burn severity subsurface soils to greater dead roots and a loss of root secretions, which are known to boost decomposition. Reduced decomposition could partly offset fire‐caused carbon loss from the ecosystem. More research is needed to clarify the long‐term effect on soil carbon. [ABSTRACT FROM AUTHOR]

Grains of paradise, which are native to Africa, contain 6-paradol, an antibacterial compound found in plants of the Zingiberaceae family. In this study, the antimicrobial and anti-virulence properties of 6-paradol were evaluated against significant Gram-negative bacteria. The assessment encompassed the impact of 6-paradol on the bacterial cell membrane, efflux mechanisms, bacterial motility, biofilm formation, and extracellular enzyme production. The findings demonstrated promising anti-quorum sensing activity of 6-paradol. Moreover, the outcomes unveiled that the antimicrobial activity of 6-paradol is primarily stems from its substantial influence on the bacterial cell membrane and efflux mechanisms. Furthermore, 6-paradol exhibited potential anti-virulence activities by effectively reducing the generation of biofilm and virulent enzymes, impeding bacterial motility, and inhibiting in vivo bacterial pathogenesis. These anti-virulence effects were attributed to the compound's interference with quorum sensing systems and the downregulation of genes associated with these systems. Additionally, when combined with antibiotics, 6-paradol demonstrated synergistic effects. In conclusion, 6-paradol possesses noteworthy anti-virulence activities and can be employed as an auxiliary alongside antibiotics for treating aggressive Gram-negative infections. This highlights its potential as a valuable addition to therapeutic strategies. [Display omitted] • 6-Paradol, is an antibacterial compound found in Zingiberaceae plants. • 6-paradol has an anti-QS activity in vitro at low concentrations. • 6-paradol can disrupt the bacterial cell membranes and hinder the efflux pumps. • 6-paradol has potential anti-virulence activity. • 6-paradol impeded bacterial motility, and inhibited in vivo bacterial pathogenesis. [ABSTRACT FROM AUTHOR]

Understanding the interactions of carbon and metal pollutants in anthropogenically impacted rivers is a prerequisite for determining the relative fates of these stressors. Here, through two sets of studies, we report carbon–metal pollutant interactions choosing the CO2 emission and sediment microbial extracellular enzyme activities as major determinants. The study, conducted along a 520-km main river and along a point source trajectory, showed a TOC-dependent but metal pollution-constrained CO2 emission. We found significant relationships (p < 0.05–0.001) between CO2 emission flux and its determinants: TOC, Cmic, FDAase and β-D-glucosidase. In the point source trajectory, CO2 emission flux was closely synchronous to these determinants. These relationships, however, were significantly constrained at the sites such as Knuj, Jjmu and Rjht where the concentrations of total heavy metal (∑THM) in the sediment exceed 347.44 µg g−1 indicating that the heavy metal pollution counteracted the C processing and consequently the CO2 emission flux. The study suggests that the excessive load of metal pollutants will eventually interrupt the C-cycling in the Ganga River inviting caution in C budgeting and C transport to coastal ocean. [ABSTRACT FROM AUTHOR]

Background: Candida albicans is still the most common cause of candidemia in the majority of healthcare-acquired bloodstream fungal infections globally with a high morbidity, mortality and significant financial burden. Yeast genotyping is crucial for designing effective infection control strategies. In the current study, we aimed to detect the genotyping, some virulence factors and antifungal resistant pattern of c. albicans isolated from immunocompromised candidemic patients admitted in critical care units of Zagazig university hospitals (ZUHs), Egypt. Methods: C. albicans isolated from clinical samples were identified and characterized using the conventional mycological methods and Vitek 2 system is used for confirming the identification and for antifungal susceptibility test (AFST). ABC genotyping was used to characterize subgroups of c. albicans and virulence activities (phospholipase (Pls), protease (Prt), esterase (Est), hemolysin (Hs), coagulase (Cgl) and biofilm formation). Results: From a total of 55 isolates of C. albicans, genotype A was the predominant (50.9%). Phospholipase and proteinase activities were detected in 96.4% and 85.4%. Esterase, hemolysin and coagulase activities were detected in 83.6%, 74.5% and 60.0% respectively. 83.6% of isolates were biofilm-forming. Isolates of c. albicans were 100% sensitive to caspofungin, micafungin and miconazole, while 1.8% are resistant for each of amphotericin B and voriconazole, while flucytosine and fluconazole showed a higher resistant (3.6%) for each. Conclusions: ABC genotyping can classify C. albicans species. The association of genotype A and resistance to flucytosine and fluconazole need further assessment. Routine AFST to guide empiric to targeted therapy should be encouraged. [ABSTRACT FROM AUTHOR]

The use of Trichoderma filamentous fungi in the wide concept of biocontrol is still a highly relevant topic. The multifaceted nature of their impact on phytopathogenic microorganisms results from the species diversity and complexity of their antagonistic action. The presented research aimed to determine optimal cultivation conditions of two T. citrinoviride strains for the biosynthesis of major enzymes especially those involved in the biocontrol process. Culture conditions were optimized using a three-factor Box-Behnken design to maximize the yield of chitinase and lichenase. The following independent variables were included in the model: incubation temperature, initial pH, and supplementation with fungal biomass. As a result of statistical optimization, unprecedented activities of extracellular lytic enzyme were achieved. For the B1 and B3 strains, the optimal pH was 3.5 or 7.5, respectively, in the determination of chitinase biosynthesis. It was similar for the biosynthesis of β-1.3 and β-1.4 glucanases, but at higher cultivation temperature. The exception was the B3 strain, for which the optimal pH in glucanase biosynthesis was 5.5. The most stimulating culture temperature in the process of chitinase biosynthesis and β-1.3 and β-1.4 glucanases was above 25 °C. In that, the levels of enzyme biosynthesis and corresponding composition culture environment were confirmed to be strain-dependent. [ABSTRACT FROM AUTHOR]

BACKGROUND: Aphid infestation adversely affects the yield and quality of crops. Rapid reproduction and insecticidal resistance have made controlling aphids in the field challenging. Therefore, the present study investigated the insecticidal property of Penicillium oxalicum (QLhf‐1) and its mechanism of action against aphids, Hyalopterus arundimis Fabricius. RESULTS: Bioassay revealed that the control efficacy of the spores against aphids (86.30% and 89.05% on the third day and fifth day after infection, respectively) were higher than other components, such as the mycelium. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that QLhf‐1 invaded the aphid cuticle through spores and used the aphid tissues as a nutrient source for growth and reproduction, causing stiffness and atrophy and a final death. Three extracellular enzymes, lipase, protease, and chitinase had a synergistic effect with spores, and they acted together to complete the infection process by degrading the aphid body wall and accelerating the infection process. CONCLUSION: The newly discovered endophytic penicillin strain P. oxalicum 'QLhf‐1' can effectively kill aphids. The results provided strong evidence for the biological control of aphids, and lay a foundation for the development and utilization of QLhf‐1. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Neural communication requires both fast-acting neurotransmitters and neuromodulators that function on slower timescales to communicate. Endogenous bioactive peptides, often called "neuropeptides," comprise the largest and most diverse class of neuromodulators that mediate crosstalk between the brain and peripheral tissues to regulate physiology and behaviors conserved across the animal kingdom. Neuropeptide signaling can be terminated through receptor binding and internalization or degradation by extracellular enzymes called neuropeptidases. Inactivation by neuropeptidases can shape the dynamics of signaling in vivo by specifying both the duration of signaling and the anatomic path neuropeptides can travel before they are degraded. For most neuropeptides, the identity of the relevant inactivating peptidase(s) is unknown. Here, we established a screening platform in C. elegans utilizing mass spectrometry-based peptidomics to discover neuropeptidases and simultaneously profile the in vivo specificity of these enzymes against each of more than 250 endogenous peptides. We identified NEP-2, a worm ortholog of the mammalian peptidase neprilysin-2, and demonstrated that it regulates specific neuropeptides, including those in the egg-laying circuit. We found that NEP-2 is required in muscle cells to regulate signals from neurons to modulate both behavior and health in the reproductive system. Taken together, our results demonstrate that peptidases, which are an important node of regulation in neuropeptide signaling, affect the dynamics of signaling to impact behavior, physiology, and aging. [Display omitted] • Neuropeptidomic screen identified a neuropeptidase, NEP-2, and its targets • NEP-2 regulates NLP-3 neuropeptides to modulate egg-laying behavior • Expression of nep-2 in muscle, and not neurons, is required for proper egg laying • Targeting NEP-2 in animals with compromised egg-laying (matricide) improves health Neuropeptidases are an important and understudied node of regulation in peptidergic circuits. Lo et al. use neuropeptidomics to identify NEP-2 as a neuropeptidase in C. elegans and simultaneously link it to endogenous peptide targets. They demonstrate how NEP-2 regulates the dynamics of peptidergic signaling to impact behavior and aging. [ABSTRACT FROM AUTHOR]

Ecoenzymatic stoichiometry can reflect the ability of soil microorganisms to acquire energy and nutrients and to determine their response to environmental stresses. However, the drivers of metabolic limitation of the moss biocrust microbiome during the ecological restoration of coal mining areas are poorly understood. Therefore, in this study, enzymatic stoichiometry modeling and high-throughput sequencing were used to simultaneously determine moss biocrust microbial metabolic limitation and its relationship with moss biocrust nutrients and arbuscular mycorrhizal fungal (AMF) diversity in five arid and semi-arid revegetation types (Hippophae rhamnoides, Amorpha fruticosa, Cerasus humilis, Cerasus szechuanica, and Xanthoceras sorbifolium) and two microbial treatments (AMF-inoculated and uninoculated). The activities of moss biocrust carbon (C)-, nitrogen (N)-, and phosphorus (P)-acquiring enzymes and organic carbon fractions in the AMF-inoculated treatment were significantly higher than those in the uninoculated control. Moss biocrust microbial community C and P limitations were observed in the five revegetation types, with lower limitation in general in the AMF-inoculated treatment. Dinitrogen-fixing plants (Amorpha fruticosa and Hippophae rhamnoides) significantly mitigated moss biocrust microbiome C and P limitation, especially in the AMF-inoculated treatment. Furthermore, partial least squares path modeling (PLS-PM) shows that moss biocrust organic carbon fractions (− 0.73 and − 0.81 of the total effects, respectively) and AMF diversity (− 0.73 and − 0.81 of the total effects) had negative effect on microbial C and P limitation, suggesting that more efficient active nutrients and AMF diversity are important factors alleviating limitation of moss biocrust microbial metabolism. This indicates that moss biocrust microbial communities under N2-fixing species with AMF inoculation were more stable under environmental stress; thus, AMF inoculation and/or N2-fixing plants may be recommended as preferred options for the ecological restoration of arid mining areas. [ABSTRACT FROM AUTHOR]

Background: Brown algae belong to the Stramenopiles phylum and are phylogenetically distant from plants and other multicellular organisms. This independent evolutionary history has shaped brown algae with numerous metabolic characteristics specific to this group, including the synthesis of peculiar polysaccharides contained in their extracellular matrix (ECM). Alginates and fucose-containing sulphated polysaccharides (FCSPs), the latter including fucans, are the main components of ECMs. However, the metabolic pathways of these polysaccharides remain poorly described due to a lack of genomic data. Results: An extensive genomic dataset has been recently released for brown algae and their close sister species, for which we previously performed an expert annotation of key genes involved in ECM-carbohydrate metabolisms. Here we provide a deeper analysis of this set of genes using comparative genomics, phylogenetics analyses, and protein modelling. Two key gene families involved in both the synthesis and degradation of alginate were suggested to have been acquired by the common ancestor of brown algae and their closest sister species Schizocladia ischiensis. Our analysis indicates that this assumption can be extended to additional metabolic steps, and thus to the whole alginate metabolic pathway. The pathway for the biosynthesis of fucans still remains biochemically unresolved and we also investigate putative fucosyltransferase genes that may harbour a fucan synthase activity in brown algae. Conclusions: Our analysis is the first extensive survey of carbohydrate-related enzymes in brown algae, and provides a valuable resource for future research into the glycome and ECM of brown algae. The expansion of specific families related to alginate metabolism may have represented an important prerequisite for the evolution of developmental complexity in brown algae. Our analysis questions the possible occurrence of FCSPs outside brown algae, notably within their closest sister taxon and in other Stramenopiles such as diatoms. Filling this knowledge gap in the future will help determine the origin and evolutionary history of fucan synthesis in eukaryotes. [ABSTRACT FROM AUTHOR]

Background: Candida species have emerged as a significant cause of opportunistic infections. Alongside the expression of various virulence factors, the rise of antifungal resistance among Candida species presents a considerable clinical challenge. Aim: This study aimed to identify different Candida species isolated from clinical specimens, evaluate their antifungal sensitivity patterns, identify key genes regulating virulence mechanisms using multiplex PCR and to assess any correlation between their virulence profiles and antifungal resistance patterns. Method: A total of 100 Candida spp. was isolated from 630 different clinical specimens and identified to the species level. Their antifungal susceptibility was phenotypically evaluated in accordance with CLSI guidelines using the Vitek-2 Compact System. Virulence markers, including biofilm formation capacity, protease production, melanin production, coagulase production and hemolysin production, were also phenotypically detected. The genetic determinants for biofilm formation and extracellular hydrolytic enzymes were assessed using a multiplex PCR assay. Results: The prevalence of Candida spp. was 15.9%, with C. albicans (48%) and C. glabrata (16%) being the most common. C. albicans showed the highest virulence, with strong biofilm formation, and high proteinase and melanin production. Multiplex PCR revealed Hlp in 22.0%, Hwp in 80.0%, Als in 56.0%, and Sap genes in 56.0% of isolates. Virulence genes were more common in C. albicans than in non-albicans Candida (NAC). Resistance patterns significantly correlated with virulence profiles, with notable associations between flucytosine resistance and the presence of Hlp and Hwp genes. Conclusion: The significant correlation between virulent markers such as germination, coagulase, hemolysin production and resistance patterns among different Candida isolates is crucial for predicting the severity and outcomes of Candida infections. This understanding aids in guiding tailored treatment strategies. [ABSTRACT FROM AUTHOR]

Aims: The accumulation of organic acids in soil can trigger autotoxicity, resulting in the continuous cropping obstacles (CCOs) for Panax notoginseng under conventional management systems. However, limited information is available about the threshold value of organic acids representing the CCOs in the soil of P. notoginseng from the forest understorey. Methods: In this study, mixed organic acids at different concentrations were exogenously applied to simulate the P. notoginseng CCO. The plant growth, edaphic factors, soil extracellular enzyme activity, and bacterial/fungal abundances and diversity in the rhizospheric soil were assessed in the P. notoginseng from the forest understorey. Results: High concentrations (>150 mg/kg) rather than low concentrations (<150 mg/kg) of organic acid decreased the dry and fresh weight of plants (1.99%-1.98%), edaphic properties (2.75%-1.03%) and soil extracellular enzyme activities (3.38%-1.05%). Under high organic acid concentrations, the fungal abundance increased by 2.37%, whereas the bacterial abundance decreased by 4.56%. Moreover, the abundance of Pseudomonadales, Xanthomonadales, and Ilyonectria as pathogenic bacteria tended to increase. Compared to bacteria, the fungal community structure varied significantly, and the fungal core flora was more abundant. The SEM results showed that the direct and indirect factors affecting the α-diversity in the rhizosphere of P. notoginseng were increased under the high organic acid concentrations. Conclusion: Organic acid concentrations greater than 150 mg/kg in P. notoginseng soils are detrimental to the relationships among plant growth, soil environment, and microbiomes, which implies the occurrence of the CCOs in P. notoginseng; and therefore, we recommend that P. notoginseng should not be planted again. [ABSTRACT FROM AUTHOR]

A major challenge in ecology is to understand how different species interact to determine ecosystem function, particularly in communities with large numbers of co‐occurring species. We use a trait‐based model of microbial litter decomposition to quantify how different taxa impact ecosystem function. Furthermore, we build a novel framework that highlights the interplay between taxon traits and environmental conditions, focusing on their combined influence on community interactions and ecosystem function. Our results suggest that the ecosystem impact of a taxon is driven by its resource acquisition traits and the community functional capacity, but that physiological stress amplifies the impact of both positive and negative interactions. Furthermore, net positive impacts on ecosystem function can arise even as microbes have negative pairwise interactions with other taxa. As communities shift in response to global climate change, our findings reveal the potential to predict the biogeochemical functioning of communities from taxon traits and interactions. [ABSTRACT FROM AUTHOR]

Subantarctic Nothofagus forests are the southernmost forests in the world, with negligible atmospheric nitrogen (N) deposition. Most paradigms about the role of ectomycorrhizal (ECM) fungi in N cycling and plant N uptake at high latitudes have been tested in boreal coniferous forests, while in the southern hemisphere, ECM hosts are primarily angiosperms. Using ITS1 meta‐barcoding, we characterized ECM and saprotrophic fungal communities in evergreen and deciduous Nothofagus forests forming monodominant and mixed stands in the archipelago of Tierra del Fuego (Chile and Argentina). We assessed the N economy of Nothofagus by correlating host species with fungal relative abundances, edaphic variables, net N mineralization, microbial biomass N and the activity of eight extracellular soil enzymes activities. The N economy of deciduous N. pumilio forests was strikingly similar to boreal coniferous forests, with the lowest inorganic N availability and net N mineralization, in correlation to higher relative abundances of ECM fungi with enzymatic capacity for organic N mobilization (genus Cortinarius). In contrast, the N economy of evergreen N. betuloides forests was predominantly inorganic and correlated with ECM lineages from the family Clavulinaceae, in acidic soils with poor drainage. Grassy understory vegetation in deciduous N. antarctica forests likely promoted saprotrophic fungi (i.e., genus Mortierella) in correlation with higher activities of carbon‐degrading enzymes. Differences between Nothofagus hosts did not persist in mixed forests, illustrating the range of soil fertility of these ECM angiosperms and the underlying effects of soil and climate on Nothofagus distribution and N cycling in southern Patagonia. [ABSTRACT FROM AUTHOR]

Litter decomposition is a crucial biochemical process regulated by microbial activities in the forest ecosystem. However, the dynamic response of the fungal community during litter decomposition to vegetation changes is not well understood. Here, we investigated the litter decomposition rate, extracellular enzyme activities, fungal community, and nutrient cycling-related genes in leaf and twig litters over a three-year decomposition period in a pure Liquidamabar formosana forest and a mixed L. formosana/Pinus thunbergii forest. The result showed that during the three-year decomposition, twig litter in the mixed forest decomposed faster than that in the pure forest. In both leaf litter and twig litter, β-cellobiosidase and N-acetyl-glucosamidase exhibited higher activities in the mixed forest, whereas phosphatase, β-glucosidase, and β-xylosidase were higher in the pure forest. The fungal α-diversity were higher in both litters in the pure forest compared to the mixed forest, with leaf litter showing higher α-diversity than twig litter. Fungal species richness and α-diversity within leaf litter increased as decomposition progressed. Within leaf litter, Basidiomycota dominated in the mixed forest, while Ascomycota dominated in the pure forest. Funguild analysis revealed that Symbiotroph and ectomycorrhizal fungi were more abundant in the mixed forest compared to the pure forest. In the third-year decomposition, genes related to phosphorus cycling were most abundant in both forests, with the pure forest having a higher abundance of cex and gcd genes. Fungal community structure, predicted functional structure, and gene composition differed between the two forest types and between the two litter types. Notably, the fungal functional community structure during the first-year decomposition was distinct from that in the subsequent two years. These findings suggest that dominant tree species, litter quality, and decomposition time all significantly influence litter decomposition by attracting different fungal communities, thereby affecting the entire decomposition process. [ABSTRACT FROM AUTHOR]

Secondary fermentation in beer can result in undesirable consequences, such as off-flavors, increased alcohol content, hyperattenuation, gushing, and the spontaneous explosion of packaging. Strains of Saccharomyces cerevisiae var. diastaticus are a major contributor to such spoilage due to their production of extracellular glucoamylase enzyme encoded by the STA1 gene. Saccharomyces yeasts can naturally produce antifungal proteins named "killer" toxins that inhibit the growth of competing yeasts. Challenging diastatic yeasts with killer toxins revealed that 91% of strains are susceptible to the K1 killer toxin produced by S. cerevisiae. Screening of 192 killer yeasts identified novel K2 toxins that could inhibit all K1-resistant diastatic yeasts. Variant K2 killer toxins were more potent than the K1 and K2 toxins, inhibiting 95% of diastatic yeast strains tested. Brewing trials demonstrated that adding killer yeast during a simulated diastatic contamination event could prevent hyperattenuation. Currently, most craft breweries can only safeguard against diastatic yeast contamination by good hygiene and monitoring for the presence of diastatic yeasts. The detection of diastatic yeasts will often lead to the destruction of contaminated products and the aggressive decontamination of brewing facilities. Using killer yeasts in brewing offers an approach to safeguard against product loss and potentially remediate contaminated beer. IMPORTANCE The rise of craft brewing means that more domestic beer in the marketplace is being produced in facilities lacking the means for pasteurization, which increases the risk of microbial spoilage. The most damaging spoilage yeasts are "diastatic" strains of Saccharomyces cerevisiae that cause increased fermentation (hyperattenuation), resulting in unpalatable flavors such as phenolic off-flavor, as well as over-carbonation that can cause exploding packaging. In the absence of a pasteurizer, there are no methods available that would avert the loss of beer due to contamination by diastatic yeasts. This manuscript has found that diastatic yeasts are sensitive to antifungal proteins named "killer toxins" produced by Saccharomyces yeasts, and in industrial-scale fermentation trials, killer yeasts can remediate diastatic yeast contamination. Using killer toxins to prevent diastatic contamination is a unique and innovative approach that could prevent lost revenue to yeast spoilage and save many breweries the time and cost of purchasing and installing a pasteurizer. [ABSTRACT FROM AUTHOR]

The present study was conducted to select Streptomyces strains that exhibited characteristics of probiotics for application in aquaculture. Streptomyces were isolated from soil and sediment samples collected from various habitats such as riverside, shrimp ponds, pangasius ponds, mangrove forests, or estuaries along the coast of Vietnam. Two strains of Streptomyces (AG12.2 and ND10.1) were selected due to (1) their potent antimicrobial activity against common pathogens that cause serious diseases in shrimp and pangasius such as E. ictaluri, A. hydophila, V. harveyi, V. parahaemolyticus, and (2) their superior ability to produce several extracellular enzymes that strongly hydrolyze organic compounds such as starch, CMC, and skimmed milk, compared to other strains. AG12.2 and ND10.1 can tolerate salinity from 0 ppt to 5 ppt and pH from 3 to 8; however, their growth is most vigorous at salt concentrations and pH between 0 ppt to 2 ppt, and 7.2 to 8, respectively. In vivo evaluation on L. vannamei in this study shows that shrimp that were fed with diets containing AG12.2 and ND10.1 had WG (%) increasing by 1.59 times and 1.61 times respectively, DGW (g/day) increasing by 1.64 times, and FCR decreasing by 1.30 times and 1.35 times respectively. The shrimp treated with AG12.2 and ND10.1 were then challenged with V. parahaemolyticus, resulting in a survival rate increase of 3.9 times and 3.71 times, respectively. Phylogenetic analysis revealed that strains AG12.2 and ND10.1 belong to Streptomyces kunmingensis and Streptomyces angustmyceticus, respectively. The findings of the present study led to the conclusion that Streptomyces kunmingensis AG12.2 and Streptomyces angustmyceticus ND10.1 are excellent candidates for producing beneficial probiotics for aquaculture. [ABSTRACT FROM AUTHOR]

One of the most important phytosanitary diseases affecting the production and marketing of the 'Hass' avocado fruit is anthracnose, mainly caused by the fungus Colletotrichum gloeosporioides. This disease is controlled with synthetic fungicides, which can cause harm to humans and the environment. Due to this, safer alternatives have been sought, such as biological control. The objective of this study was to isolate and characterize Bacillus spp. strains that biocontrol C. gloeosporioides in 'Hass' avocado fruits. The isolation, purification, and molecular identification of bacteria with biocontroller capacity was carried out. In vitro and in vivo tests were carried out against the pathogen C. gloeosporioides. Furthermore, the percentage inhibition of spore germination, enzymatic profile, and nutrient assimilation were determined. Forty-three native bacterial strains were isolated from the 'Hass' avocado fruit. The strains that showed the greatest antagonistic capacity in vivo against C. gloeosporioides were Bacillus pumilus AB31, B. thuringiensis AB30, B. thuringiensis AB7, and B. thuringiensis AB21. These strains could produce extracellular enzymes, such as phosphatases, proteases, and β-glucosidase, as well as the assimilation of D-ribose and trehalose. The above favors their antagonistic activity. Four strains of the genus Bacillus (one B. pumilus and three B. thuringiensis) can control C. gloeosporioides in 'Hass' avocado. [ABSTRACT FROM AUTHOR]

Extracellular enzymes produced by fungi can serve as a screening tool for entomopathogen candidates. Enzyme secretion ability is important in determining the virulence level of an entomopathogenic fungus. This study aims to see the potential of fungal isolates through chitinolytic, lipolytic, and proteolytic activities of five entomopathogenic fungal isolated from Bactrocera sp. imago from citrus plants. The research was carried out at the Microbiology Laboratory of the Department of Biology at the University of Lampung. Enzymatic activity is known through the method of observing the clear zone formed on agar media. Quantitative tests based on the calculation of enzymatic index values showed that Nigrospora sp. (IB1) had lipolytic activity, Penicillium sp. 2 (IB5) isolates had chitinolytic, lipolytic, and proteolytic activities. The isolates of Penicillium sp. 1 (IB2), Phytopthora sp. (IB3), and Gliocladium sp. (IB4) did not show the activity of the three enzymes. [ABSTRACT FROM AUTHOR]

Herbivorax saccincola A7 is an anaerobic alkali-thermophilic lignocellulolytic bacterium that possesses a cellulosome and high xylan degradation ability. To understand the expression profile of extracellular enzymes by carbon sources, quantitative real-time PCR was performed on all cellulosomal and non-cellulosomal enzyme genes of H. saccincola A7 using cellulose and xylan as carbon sources. The results confirmed that the scaffolding proteins of H. saccincola A7 were expressed. In general, the cellulosomal genes belonging to the glycoside hydrolase families 9, 10, 11, and 48 were repressed when xylan was the sole carbon source, but these genes were significantly induced in the presence of cellulose. These results indicate that cellulose, not xylan, is a key inducer of cellulosomal genes in H. saccincola A7. The RsgI-like proteins, which regulate a carbohydrate-sensing mechanism in Clostridium thermocellum, were also found to be encoded in the H. saccincola A7 genome. To confirm the regulation by RsgI-like proteins, the relative expression of σI1–σI4 factors was analyzed on both carbon sources. The expression of alternative σI1 and σI2 factors was enhanced by the presence of cellulose. By contrast, the expression of σI3 and σI4 factors was activated by both cellulose and xylan. Taken together, the results reveal that the cellulosomal and non-cellulosomal genes of H. saccincola A7 are regulated through a carbohydrate-sensing mechanism involving anti-σ regulator RsgI-like proteins. Key points: • qRT-PCR performed on cellulosomal and non-cellulosomal genes of H. saccincola A7 • Cellulose is a key inducer of the cellulosome of H. saccincola A7 • H. saccincola A7 possesses a similar system of anti-σ regulator RsgI-like proteins [ABSTRACT FROM AUTHOR]

Few studies have investigated the biodegradation of microplastics in marine environments. Microorganisms that can degrade microplastics in high-salinity conditions are sought after. Therefore, we aimed to isolate a halotolerant poly(ε-caprolactone) (PCL)-degrading bacterium for applications in biotechnology. The bacterium isolated from seaside soil was identified as Bacillus gibsonii via phylogenetic analysis based on 16S rRNA gene sequences and designated as KRICT-1. We tested whether the KRICT-1 strain showed halotolerance by determining the sodium chloride (NaCl) tolerance at various concentrations. The KRICT-1 strain showed growth at up to 10% NaCl on Luria–Bertani (LB) medium agar plates and 10% NaCl in liquid LB medium, indicating that KRICT-1 can grow and produce a PCL-depolymerizing enzyme under high-salt conditions. The KRICT-1 strain could depolymerize PCL with a PCL film weight loss of 2.82% at up to 10% NaCl concentration after cultivation of 7 weeks. KRICT-1 is the first strain of B. gibsonii which shows PCL-depolymerizing activity. Scanning electron microscopy and water contact angle results confirmed the degradation of PCL by the KRICT-1 strain. The extracellular enzyme produced by the KRICT-1 strain was stable over a wide range of temperatures (15–40 °C) and pH (7.0–9.5). This halotolerant PCL-degrading bacterium can be used in the degradation of biodegradable plastics present in saline soils, saline water, and wastewater. [ABSTRACT FROM AUTHOR]

Two strains of Yarrowia lipolytica (CBS 2075 and DSM 8218) were first studied in bioreactor batch cultures, under different controlled dissolved oxygen concentrations (DOC), to assess their ability to assimilate aliphatic hydrocarbons (HC) as a carbon source in a mixture containing 2 g·L−1 of each alkane (dodecane and hexadecane), and 2 g·L−1 hexadecene. Both strains grew in the HC mixture without a lag phase, and for both strains, 30 % DOC was sufficient to reach the maximum values of biomass and lipids. To enhance lipid-rich biomass and enzyme production, a pulse fed-batch strategy was tested, for the first time, with the addition of one or three pulses of concentrated HC medium. The addition of three pulses of the HC mixture (total of 24 g·L−1 HC) did not hinder cell proliferation, and high protease (> 3000 U·L−1) and lipids concentrations of 3.4 g·L−1 and 4.3 g·L−1 were achieved in Y. lipolytica CBS 2075 and DSM 8218 cultures, respectively. Lipids from the CBS 2075 strain are rich in C16:0 and C18:1, resembling the composition of palm oil, considered suitable for the biodiesel industry. Lipids from the DSM 8218 strain were predominantly composed of C16:0 and C16:1, the latter being a valuable monounsaturated fatty acid used in the pharmaceutical industry. Y. lipolytica cells exhibited high intrinsic surface hydrophobicity (> 69 %), which increased in the presence of HC. A reduction in surface tension was observed in both Y. lipolytica cultures, suggesting the production of extracellular biosurfactants, even at low amounts. This study marks a significant advancement in the valorization of HC for producing high-value products by exploring the hydrophobic compounds metabolism of Y. lipolytica. [ABSTRACT FROM AUTHOR]

A novel Pseudochrobactrum saccharolyticum strain NBRI-CRB 13, isolated from tannery sludge, was studied to grow up to 500 mgL−1 of Cr(VI) and showed Cr(VI) detoxification by reducing > 90% of Cr(VI) at different concentrations 25, 50 and 100 mgL−1. Kinetic studies showed that first-order models were fitted (R2 = 0.998) to the time-dependent Cr(VI) reduction with degradation rate constant (k) (1.03–0.429 h−1). Cr(VI) detoxification was primarily related to the extracellular fraction of microbial cells, which showed a maximum extracellular reductase enzyme activity led to 94.6% reduction of Cr(VI). Moreover, the strain showed maximum extracellular polymeric substances (EPS) production at 100 mgL−1 Cr(VI), which is presumably the reason for Cr(VI) removal as EPS serves as the metal binding site for Cr(VI) ions. Further, an optimization study using Box-Behnken design was conducted considering parameters viz., pH, temperature, and initial concentration of Cr(VI). The maximum percent reduction of Cr(VI) was obtained at pH 6.5, temperature 30 °C with 62.5 mgL−1Cr(VI) concentration. Further, the Cr(VI) reduction and adsorption ability of strain P. saccharolyticum NBRI-CRB13 were confirmed by SEM–EDS, FTIR, and XRD analyses. FTIR analysis confirmed the presence of functional groups (–OH, –COOH, –PO4) on bacterial cell walls, which were more likely to interact with positively charged chromium ions. The study elucidated the reduction of Cr(VI) by the novel bacterium within 24 h using the response surface methodology approach and advocated its application in real-time situations. [ABSTRACT FROM AUTHOR]

• The isolated strain Providencia rettgeri was capable of degrading TCPP efficiently. • The degradation of TCPP was mainly via phosphoester bond hydrolysis. • BCPP (C6H13Cl2PO4) and MCPP (C3H8ClPO4) were the main degradation intermediates. • Both intracellular and extracellular enzymes could degrade TCPP. • The presence of Cu2+ had a promoting effect on TCPP degradation by enzyme. Tri (2-chloropropyl) phosphate (TCPP) was an emerging contaminant of global concern because of its frequent occurrence, potential toxic effects, and persistence in the environment. Microbial degradation might be an efficient and safe removal method, but limited information was available. In this study, Providencia rettgeri was isolated from contaminated sediment and showed it could use TCPP as unique phosphorus source to promote growth, and decompose 34.7% of TCPP (1 mg/L) within 5 days. The microbial inoculation and the initial concentration of TCPP could affect the biodegradation efficient. Further study results indicated that TCPP decomposition by Providencia rettgeri was mainly via phosphoester bond hydrolysis, evidenced by the production of bis (2-chloropropyl) phosphate (C 6 H 13 Cl 2 PO 4) and mono-chloropropyl phosphate (C 3 H 8 ClPO 4). Both intracellular and extracellular enzymes could degrade TCPP, but intracellular degradation was dominant in the later reaction stage, and the presence of Cu2+ ions had a promoting effect. These findings developed novel insights into the potential mechanism of TCPP microbial degradation. [Display omitted] [ABSTRACT FROM AUTHOR]

Defoliation by eastern spruce budworm is one of the most important natural disturbances in Canadian boreal and hemi‐boreal forests with annual area affected surpassing that of fire and harvest combined, and its impacts are projected to increase in frequency, severity, and range under future climate scenarios. Deciding on an active management strategy to control outbreaks and minimize broader economic, ecological, and social impacts is becoming increasingly important. These strategies differ in the degree to which defoliation is suppressed, but little is known about the downstream consequences of defoliation and, thus, the implications of management. Given the disproportionate role of headwater streams and their microbiomes on net riverine productivity across forested landscapes, we investigated the effects of defoliation by spruce budworm on headwater stream habitat and microbiome structure and function to inform management decisions. We experimentally manipulated a gradient of defoliation among 12 watersheds during a spruce budworm outbreak in the Gaspésie Peninsula, Québec, Canada. From May through October of 2019–2021, stream habitat (flow rates, dissolved organic matter [DOM], water chemistry, and nutrients), algal biomass, and water temperatures were assessed. Bacterial and fungal biofilm communities were examined by incubating six leaf packs for five weeks (mid‐August to late September) in one stream reach per watershed. Microbiome community structure was determined using metabarcoding of 16S and ITS rRNA genes, and community functions were examined using extracellular enzyme assays, leaf litter decomposition rates, and taxonomic functional assignments. We found that cumulative defoliation was correlated with increased streamflow rates and temperatures, and more aromatic DOM (measured as specific ultraviolet absorbance at 254 nm), but was not correlated to nutrient concentrations. Cumulative defoliation was also associated with altered microbial community composition, an increase in carbohydrate biosynthesis, and a reduction in aromatic compound degradation, suggesting that microbes are shifting to the preferential use of simple carbohydrates rather than more complex aromatic compounds. These results demonstrate that high levels of defoliation can affect headwater stream microbiomes to the point of altering stream ecosystem productivity and carbon cycling potential, highlighting the importance of incorporating broader ecological processes into spruce budworm management decisions. [ABSTRACT FROM AUTHOR]

Phosphorus (P), a crucial element for all life forms on Earth, is often insufficiently available in terrestrial ecosystems. The interaction and feedback between plants and soil microorganisms are crucial links integrating above‐ and below‐ground ecosystems. However, changes in soil P fractions in response to plant‐microbe interactions during vegetation succession remain poorly understood. This study investigated the trends and relationships between plant resorption, microbial properties, and soil P fractions in the transformation interface soil layer (TIS) and underlying topsoil layer (UTS) during grassland vegetation succession. The results point to a combination of soil properties, alongside microbial and plant factors driving soil P changes. However, the TIS and UTS layers differ, with phosphorus dynamics in the TIS layer primarily influenced by microorganisms. Microorganisms are co‐limited by C and P in both the TIS and UTS layers. Under microbial P‐limitation, microorganisms produce alkaline phosphatases (AP), while C deficiency stimulates the production of C‐acquiring enzymes, subtly regulating soil P dynamics through organic matter decomposition. Plant P resorption efficiency and microbial P‐limitation exhibit synergistic variations, reaching their lowest levels during the mixed Bothriochloa ischaemum and Stipa bungeana Trin (Bo.I + St.B) stage. This study emphasizes that P cycling is influenced by plant‐microbe‐soil interactions and feedback. Plants and soil microorganisms jointly regulate soil nutrient effectiveness and partitioning in the ecosystem. Plain Language Summary: Phosphorus (P) is an indispensable element found in all living organisms, essential for various biological functions like photosynthesis, energy transfer, and the synthesis of DNA and RNA. Focusing on vegetation restoration, we found that soil microorganisms faced limitations from both P and carbon (C). Notably, in the soil layer at the transformation interface, where plant litter was plentiful, microorganisms enjoyed improved access to P. This improvement was attributed to the plants in our study absorbing more nitrogen (N) than P, resulting in a higher concentration of P in their decomposing foliage. Furthermore, the production of alkaline phosphatase (AP) by microbes facilitates their access to additional P from the soil. From the viewpoint of P acquisition, an increase in microbial P‐limitation leads to a reduction in dissolved inorganic P, thereby enhancing the efficiency of plant P resorption. This process ultimately results in a net decrease in the total soil P content. Understanding the dynamics of P cycling in soil amid vegetation restoration is vital for the sustainable management of land. By ensuring that both plants and microorganisms have adequate access to P, we can foster successful and eco‐friendly vegetation restoration initiatives. Key Points: Microbial P limitation is more pronounced in the underlying topsoil layer compared to the transformation interface soil layerMicrobial factors such as extracellular enzymes are the main drivers of P variation within the transformation interface soil layerDuring the course of vegetation succession, microbial P‐limitation is found to enhance plant P resorption efficiency [ABSTRACT FROM AUTHOR]

Agroforestry ecosystems are an efficient strategy for enhancing soil nutrient conditions and sustainable agricultural development. Soil extracellular enzymes (EEAs) are important drivers of biogeochemical processes. However, changes in EEAs and chemometrics in rubber-based agroforestry systems and their mechanisms of action are still not fully understood. Distribution of EEAs, enzymatic stoichiometry, and microbial nutrient limitation characteristics of rubber plantations under seven planting patterns (RM, rubber monoculture system; AOM, Hevea brasiliensis-Alpinia oxyphylla Miq; PAR, Hevea brasiliensis-Pandanus amaryllifolius Roxb; AKH, Hevea brasiliensis-Alpinia katsumadai Hayata; CAA, Hevea brasiliensis-Coffea Arabica; CCA, Hevea brasiliensis-Cinnamomum cassia (L.) D. Don, and TCA, Hevea brasiliensis-Theobroma Cacao) were analyzed to investigate the metabolic limitations of microorganisms and to identify the primary determinants that restrict nutrient limitation. Compared with rubber monoculture systems, agroforestry ecosystems show increased carbon (C)-acquiring enzyme (EEAC), nitrogen (N)-acquiring enzyme (EEAN), and phosphorus (P)-acquiring enzyme (EEAP) activities. The ecoenzymatic stoichiometry model demonstrated that all seven plantation patterns experienced C and N limitation. Compared to the rubber monoculture system, all agroforestry systems exacerbated the microbial limitations of C and N by reducing the vector angle and increasing vector length. P limitation was not detected in any plantation pattern. In agroforestry systems, progression from herbs to shrubs to trees through intercropping results in a reduction in soil microbial nutrient constraints. This is primarily because of the accumulation of litter and root biomass in tree-based systems, which enhances the soil nutrient content (e.g., soil organic carbon, total nitrogen, total phosphorus, and ammonium nitrogen) and accessibility. Conversely, as soil depth increased, microbial nutrient limitations tended to become more pronounced. Partial least squares path modelling (PLS-PM) indicated that nutrient ratios and soil total nutrient content were the most important factors influencing microbial C limitation (−0.46 and 0.40) and N limitation (−0.30 and −0.42). This study presented novel evidence regarding the constraints and drivers of soil microbial metabolism in rubber agroforestry systems. Considering the constraints of soil nutrients and microbial metabolism, intercropping of rubber trees with arboreal species is recommended over that of herbaceous species to better suit the soil environment of rubber plantation areas on Hainan Island. [ABSTRACT FROM AUTHOR]

The impact of nitrogen and phosphorus deposition alternations, as well as apoplastic litter quality and quantity, on soil nutrient cycling and soil carbon pool processes in forest ecosystems is of considerable importance. Soil ecological enzyme chemistry is a powerful tool for elucidating the nutrient limitations of microbial growth and metabolic processes. In order to explore the responding mechanisms of soil ecological enzyme chemistry to the simultaneous changes in apoplast input and nitrogen and phosphorus deposition in temperate coniferous and broad-leaved mixed forests, an outdoor simulating experiment was conducted. The results demonstrate that the treatments involving apoplastic material and nitrogen and phosphorus additions had significantly impacted soil nutrient levels across different forest types. Apoplastic treatments and N-P additions had a significant effect on the soil total organic carbon (TOC), dissolved organic carbon (DOC), soil total soluble nitrogen (TSN), soil available phosphorus (SAP), soil total nitrogen (TN), soil total phosphorus (TP), and microbial biomass carbon (MBC). However, the effects on soil microbial biomass (MBN) and microbial biomass phosphorus (MBP) were insignificant. The apomictic treatments with N and P addition did not result in a statistically significant change in soil C-hydrolase activities (β-1,4-glucosidase BG, β-1,4-xylosidase BX, cellobiohydrolase CBH, phenol oxidase POX, and peroxidase PER), N-hydrolase activities (β-1,4-N-acetylglucosaminidase NAG and L-leucine aminopeptidase LAP), or P-hydrolase activities (Acid phosphatase AP). Although the apomictic treatments did not yield a significant overall impact on carbon hydrolase activity, they influenced the activity of specific enzymes, such as CBH, LAP, and PER, to varying degrees. The effects on BG, BX, CBH, AP, and C-hydrolase activities were significant for different stand types. The impact of apomictic treatments and N-P additions on soil nitrogen hydrolase activities was inconsequential with a minimal interactive effect. The highest correlation between PER, LAP, and N-hydrolase activities was observed in conjunction with elevated levels of nitrogen and phosphorus addition (N3L0, original litter treatment, and high amounts of N and P addition). These findings may provide a theoretical foundation for the management of ecosystem function in broad-leaved Korean pine forests. [ABSTRACT FROM AUTHOR]

BACKGROUND: To discover more efficient agricultural antimicrobial agents, a series of new quinazoline derivatives containing both a piperazine linker and the N‐acetyl moiety were prepared and assessed for their antibacterial and antifungal activities. RESULTS: All the target compounds were characterized by 1H and 13C NMR as well as high‐resolution mass spectrometry (HRMS), and the chemical structure of the most potent compound E19 incorporating a 4‐trifluoromethoxy substituent was clearly confirmed via single crystal X‐ray diffraction measurements. The bioassay results indicated that some compounds possessed notable inhibitory effects in vitro against the bacterium Xanthomonas oryzae pv. oryzicola (Xoc). For example, compound E19 had an EC50 (effective concentration for 50% activity) value of 7.1 μg/mL towards this pathogen, approximately 15‐ and 10‐fold more effective than the commercial bactericides thiodiazole copper and bismerthiazol (EC50 = 110.2 and 72.4 μg/mL, respectively). Subsequently, the mechanistic studies showed that compound E19 likely exerted its antibacterial efficacies by altering the cell morphology, increasing the permeability of bacterial cytoplasmic membrane, suppressing the production of bacterial extracellular polysaccharides and the extracellular enzyme activities (amylase and cellulase), and blocking the swimming motility of Xoc. Moreover, the proteomic analysis revealed that compound E19 could reduce the bacterial flagellar biosynthesis and decrease the flagellar motility by down‐regulating the expression of the related differential proteins. CONCLUSION: Compound E19 exhibited good potential for further development as a bactericide candidate for control of Xoc. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In the current study, the ability of an indigenous marine Actinomycete Nocardiopsis dassonvillei (NCIM 5124) to degrade poly(3-hydroxybutyrate)-PHB was examined. From the whole genome sequencing data of the organism, information regarding the PHB depolymerase gene and amino acid sequence (Accession number: MCK9871921.1) was retrieved. In silico studies indicated the presence of a signal peptide characteristic of extracellular enzymes. ProtParam tool predicted that the protein had a molecular mass of 42.46 kDa with an isoelectric point of 4.51. Aliphatic and instability index values suggested that the protein was stable and the observed GARVY value indicated its hydrophilic nature. 3D structure prediction and multiple sequence alignments revealed the presence of Type I catalytic domain [including the oxyanion histidine towards the N terminal, the catalytic triad with serine (as a part of GLSAG pentapeptide), aspartate and histidine], substrate binding and linker domain. The organism was able to grow on PHB in solid and liquid media and effectively degrade it. Maximum enzyme activity (1.8 U/mL/min) was observed after 5 d of incubation in Bushnell Hass Medium containing 0.1% PHB, 1.5% sodium chloride, at 30 °C, pH 7.5 with agitation at 130 rpm. Application of the organism in disintegrating films of PHB and its copolymers was successfully demonstrated on the basis of weight loss and scanning electron microscope analysis. To the best of our knowledge, this is the first report on production of PHB depolymerase with high efficiency by N. dassonvillei, an organism that holds promise in degrading PHB-derived waste material. [ABSTRACT FROM AUTHOR]

Bacterial virulence plays an important role in infection. Antibacterial virulence factors are effective for preventing crop bacterial diseases. Resin acid copper salt as an effective inhibitor exhibited excellent anti-Xanthomonas oryzae pv. oryzae (Xoo) activity with an EC50 of 50.0 μg mL−1. Resin acid copper salt (RACS) can reduce extracellular polysaccharides' (EPS's) biosynthesis by down-regulating gumB relative expression. RACS can also effectively inhibit the bio-mass of Xoo biofilm. It can reduce the activity of Xoo extracellular amylase at a concentration of 100 μg mL−1. Meanwhile, the results of virtual computing suggested that RACS is an enzyme inhibitor. RACS displayed good curative activity with a control effect of 38.5%. Furthermore, the result of the phytotoxicity assessment revealed that RACS exhibited slight toxicity compared with the control at a concentration of 200 μg mL−1. The curative effect was increased to 45.0% using an additional antimicrobial agent like orange peel essential oil. RACS markedly inhibited bacterial pathogenicity at a concentration of 100 μg mL−1 in vivo. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is a ubiquitous environmental Gram-negative bacterium and also an opportunistic pathogen for both humans and animals, causing acute or chronic infections. It has been frequently detected in healthy and diseased reptiles, more commonly in captive ones. Since most studies are primarily on clinical isolates, the pathogenic potential of strains originating from wild animals is poorly explored. We isolated the strain P. aeruginosa PM1012 from the cloacal microbiota of a common wall lizard (Podarcis muralis Laurenti, 1768) from a free-living population. The effect of temperature, pH and salinity on its growth was evaluated. Antibiotic resistance, the expression of several virulence factors as some extracellular enzymes, pyocyanin production and biofilm formation were also assessed. Apart from intrinsic resistance, the newly isolated strain P. aeruginosa PM1012 presented an antibiotic susceptibility profile with a low resistance rate limited to meropenem and intermediate to ceftazidime and aztreonam. Protease, lipase and gelatinase secretion was detected. Strong pyocyanin production was observed in the optimal range of growth conditions. An excellent biofilm-forming capacity was manifested. [ABSTRACT FROM AUTHOR]

Trichoderma is a soil-dwelling microorganism that has many benefits for plants and is therefore widely used in agriculture. Among the secondary metabolites produced by Trichoderma, gliotoxin (GT) is one of the most studied. The antagonistic effect of GT on other fungi was first discovered by R. Weindling in 1934. He referred to it as the "lethal principle" of Trichoderma. Despite the long history of studying GT, its impact on the soil microbial community has remained largely unexplored. In our work, we investigated the response of the soil microbial community to different doses of GT (10–500 µM per kg) and different durations (7–56 days) of exposure. We measured microbiological parameters (CO2 emission, microbial biomass (MB)), calculated the eco-physiological indices and determined the activity of soil enzymes involved in the C, N, P and S cycles. We identified three types of microbial responses to GT: inhibition, stress and stimulation. The inhibitory effect developed only by day 56 and in the samples treated with 500 μM GT. The stress effect (increased CO2 emission and decreased MB) of GT on microbial communities was predominant. Soil extracellular enzymes also responded to GT to varying degrees. A stimulating effect of GT on enzyme activity was noted for β-D-1,4-cellobiosidase and β-1,4-glucosidase. The activity of arylsulfatase and leucine aminopeptidase decreased under the influence of GT up to day 28, but by the end of the experiment, there was a restoration of activity. We did not observe any significant changes in the activity of β-1,4-xylosidase, β-1,4-N-acetyl-glucosaminidase or acid phosphatase. The results obtained showed that GT at high, "man-made" doses can inhibit the microbiological activity of soil, but at naturally occurring concentrations, it can have a stimulating effect on soil microbiome functionality. [ABSTRACT FROM AUTHOR]

Biological soil crusts (biocrusts) are crucial elements of desert ecosystems, exhibiting patchy distribution patterns across the soil surface and significantly impacting surface soil nutrient dynamics. However, the influence of biocrust patch units, serving as fundamental functional entities, on microbial nutrient restriction remains underexplored. This study conducted measurements on moss crust patches of varying sizes and subcrust soils. Stoichiometric analysis of extracellular enzyme activities (EEAs) related to carbon, nitrogen, and phosphorus was performed, along with vector and redundancy analyses to evaluate microbial nutrient limitation and key influencing factors. The findings reveal that both patch size and soil layer of biocrusts collectively influence soil nutrients and enzyme dynamics, with heightened enzyme activity observed in the crust layer. Vector analysis based on EEA stoichiometry indicates that moss crust patch size insignificantly impacts microbial nutrient restriction within the crust layer. However, microbial nitrogen restriction in the subcrust layer demonstrates a “single-peak” trend, initially increasing before gradually declining. This suggests that microorganisms in medium-sized crust patches exhibit peak activity, intensifying nutrient competition. This research underscores the pivotal role of biocrust patch units as fundamental functional entities, offering comprehensive insights into microbial metabolic constraints under crust cover. The findings underscore the significant implications of enzyme stoichiometric characteristics for desert land management and conservation. [ABSTRACT FROM AUTHOR]

The relationships between plants and bacteria are essential in agroecosystems and bioinoculant development. The leaf endophytic Pseudomonas protegens E1BL2 was previously isolated from giant Jala maize, which is a native Zea mays landrace of Nayarit, Mexico. Using different Mexican maize landraces, this work evaluated the strain's plant growth promotion and biocontrol against eight phytopathogenic fungi in vitro and greenhouse conditions. Also, a plant field trial was conducted on irrigated fields using the hybrid maize Supremo. The grain productivity in this assay increased compared with the control treatment. The genome analysis of P. protegens E1BL2 showed putative genes involved in metabolite synthesis that facilitated its beneficial roles in plant health and environmental adaptation (bdhA, acoR, trpE, speE, potA); siderophores (ptaA, pchC); and extracellular enzymes relevant for PGPB mechanisms (cel3, chi14), protection against oxidative stress (hscA, htpG), nitrogen metabolism (nirD, nit1, hmpA), inductors of plant-induced systemic resistance (ISR) (flaA, flaG, rffA, rfaP), fungal biocontrol (phlD, prtD, prnD, hcnA-1), pest control (vgrG-1, higB-2, aprE, pslA, ppkA), and the establishment of plant-bacteria symbiosis (pgaA, pgaB, pgaC, exbD). Our findings suggest that P. protegens E1BL2 significantly promotes maize growth and offers biocontrol benefits, which highlights its potential as a bioinoculant. [ABSTRACT FROM AUTHOR]

Corn cobs consist primarily of a lignocellulosic material comprising hemicellulose, cellulose, and lignin in a crystalline state, which is resistant to microbial saccharification. Bioethanol production from corn cobs has rarely been attempted, especially using chemical pretreatment methods. The present study deals with the production and purification of fungal (Phanerochaete chrysosporium MTCC 787 and Pleurotus florida PAU 22‐01) extracellular ligninolytic enzymes – lignin peroxidase (LiP), manganese peroxidase (MnP), and laccase (Lac) – followed by their utilization for the biological pretreatment of corn cobs along with saccharification using commercial cellulase. Crude LiP, MnP, and Lac demonstrated specific activity of 2.23, 2.1, and 2.63 U/mg, respectively. The one‐step purification of crude enzyme using diethyl amino ethyl (DEAE) cellulose ion exchange chromatography resulted in 11.3, 10.1 and 8.62‐fold purification of LiP, MnP and Lac activity, respectively, with corresponding specific activity of 25.1 U/mg (LiP), 21.2 U/mg (MnP) and 22.7 U/mg (Lac) in the partially purified ligninozymes. Using the latter, biological pretreatment of 2.5 g corn cobs in a reaction volume of 30 mL containing approximately 200 units of Lac, Lip and MnP enzymes (in phosphate buffer, pH 6) resulted in a maximum of 78.4% delignification with a saccharification efficiency of 97.1% using commercial cellulases. [ABSTRACT FROM AUTHOR]

The color of textile wastewater is still a main problem in wastewater treatment by biological processes. The colored effluents from textile factories usually exceed effluent standards. Therefore, various innovations were developed to treat textile wastewater for decolorization in the effluents. This research aims to decolorize textile wastewater by immobilizing white rot fungi degradation. At first, the 11 fungal stains were tested to find the decolorized efficiency then the high decolorized efficiency fungal stains were immobilized on four material media, namely water hyacinth stalks, coconut husk, corn cob, and loofah. After that, the immobilized fungi were cultivated in the culture media at 30, 60, and 120 C/N ratios, respectively. The results showed that Trametes sanguinea and Perenniporia tephropora were two stains with a high decolorized efficiency of 68.8% and 67.5% respectively, and the decolorized efficiency was increased when immobilized on loofahs and fed with 120 C/N ratio medium. In a comparison of two fungal stains, P. tephropora was found more suitable for the decolorization of textile wastewater than T. sanguinea because T. sanguinea could produce red-orange pigments that induced the colored enhancement in wastewater over time. Finally, immobilized P. tephropora was cultivated in a 120 C/N ratio medium within a 10 L continuous stirred tank reactor (8 L working volume) to investigate the decolorized efficiency, enzymatic activity, and repeated batch. It was found that three repeated cycles were carried out by reusing the immobilized P. tephropora and the highest decolorized efficiency was 63.4%. The enzymatic activity of laccase, manganese peroxidase, and lignin peroxidase was 15.5 U/L, 85.9 U/L, and 0 U/L, respectively [ABSTRACT FROM AUTHOR]

Purpose: The influence of organic amendments on the interplay among soil extracellular enzyme activities (EEAs) and their stoichiometry (EES) and nutrient availabilities, key indicators of resource limitations for soil microbes, is poorly understood. This study aims to investigate how manure compost (hereafter "manure") and its biochar derivative affect EEAs, EES and soil fertility. Materials and methods: We studied EEAs (BG, β-glucosidase; CBH, cellobiohydrolase; LAP, Leucine aminopeptidase; NAG, β-1,4-N-acetylglucosaminidase and AP, acid phosphatase), EES and soil fertility two years post-application of manure and biochar in central Alberta, Canada. Results and discussion: Applying manure and its biochar did not affect soil permanganate oxidable carbon (C), total phosphorus (P), and available P and nitroegn (N). Manure application increased NAG activity by 13.9% (75.9 nmol h−1 g−1 soil) relative to the control (66.6 nmol h−1 g−1 soil), whereas biochar application increased LAP activity by 22.1% (64.6 nmol h−1 g−1 soil) compared to the manure treatment (52.9 nmol h−1 g−1 soil), suggesting that manure addition caused microbial C limitation, while biochar addition led to microbial N limitation. However, both manure and biochar treatments did not affect soil NAG, CBH and AP, and enzymatic C:N, C:P, and N:P stoichiometry. Manure and biochar and their interactions with the soil ultimately affect soil physicochemical properties. Conclusions: Manure and its biochar differentially altered some soil N-cycling EEAs and C and N limitations two years after their applications. [ABSTRACT FROM AUTHOR]

Introduction: Rhizosphere effects (REs) have recently been identified as important regulators of root and microbial nutrient acquisition and are positively involved in nutrient cycling of belowground carbon (C), nitrogen (N), and phosphorus (P). Nutrient conditions of the fine roots and soil N are likely to influence REs. Still, it is unclear how REs of soil nutrients themselves variably impact the supply of nutrients to plants in terms of the responses to soil N due to succession. Methods: In this study, we applied both fine roots and extracellular enzymes for vector analysis and stoichiometry of N:P to explore the metabolic limitations of roots and rhizospheric soil microbes and their relationships with REs across five levels of soil N (0, 5, 10, 15, and 20 kg N m-2 year-1) along successional age classes of 42, 55, and 65 years in a Pinus tabuliformis forest. Results: Overall, the metabolism of root and rhizospheric soil microbes was mediated by soil N. N limitation of roots initially decreased before increasing, whereas that of microbes demonstrated opposite trends to the N levels owing to competition for inorganic N between them by REs of NO3--N. However, N limitations of both roots and microbes were alleviated in young stands and increased with succession after the application of N. In addition, root N limitations were manipulated by REs of three different soil N-related indicators, i.e., total N, NH4 +-N, and NO3 --N. Rhizospheric soil microbial N limitation was almost unaffected by REs due to their strong homeostasis but was an important driver in the regulation of root N limitation. Discussion: Our results indicated that successional age was the most critical driver that directly and indirectly affected root N metabolism. However, the level of N application had a slight effect on root N limitation. Microbial N limitation and variations in the REs of N indicators regulated root N limitation in the rhizosphere. As a result, roots utilized REs to sequester N to alleviate N limitations. These findings contribute to novel mechanistic perspectives on the sustainability of N nutrition by regulating N cycling in a system of plant-soil-microbes in the rhizosphere to adapt to global N deposition or the heterogeneous distribution of bioavailable soil N with succession. [ABSTRACT FROM AUTHOR]

Although depolymerization of complex carbohydrates is a growth-limiting bottleneck for microbial decomposers, we still lack understanding about how the production of different types of extracellular enzymes affect individual microbes and in turn the performance of whole decomposer communities. In this work we use a theoretical model to evaluate the potential trade-offs faced by microorganisms in biopolymer decomposition which arise due to the varied biochemistry of different depolymerizing enzyme classes. We specifically consider two broad classes of depolymerizing extracellular enzymes, which are widespread across microbial taxa: exo-enzymes that cleave small units from the ends of polymer chains and endo-enzymes that act at random positions generating degradation products of varied sizes. Our results demonstrate a fundamental trade-off in the production of these enzymes, which is independent of system's complexity and which appears solely from the intrinsically different temporal depolymerization dynamics. As a consequence, specialists that produce either exo- or only endo-enzymes limit their growth to high or low substrate conditions, respectively. Conversely, generalists that produce both enzymes in an optimal ratio expand their niche and benefit from the synergy between the two enzymes. Finally, our results show that, in spatially-explicit environments, consortia composed of endo- and exo-specialists can only exist under oligotrophic conditions. In summary, our analysis demonstrates that the (evolutionary or ecological) selection of a depolymerization pathway will affect microbial fitness under low- or high substrate conditions, with impacts on the ecological dynamics of microbial communities. It provides a possible explanation why many polysaccharide degraders in nature show the genetic potential to produce both of these enzyme classes. Author summary: The decomposition of polysaccharides by microbes is a key process in the global carbon cycle. It requires the joint action of a variety of microbially-produced extracellular enzymes. They can be broadly classified into endo-enzymes, that act in the middle of polymers, and exo-enzymes, that cleave units from polymer ends. Little is known about the benefits for microbes producing a certain enzyme type and the interplay between enzyme producing strategies in mixed communities. This hampers our comprehensive understanding of decomposition in terrestrial and marine ecosystems and thus limits the prediction of decomposition processes, for example in a changing climate. Based on theoretical modelling, we revealed a fundamental trade-off in the action of these enzymes. While exo-enzymes are more efficient at high substrate conditions, endo-enzymes perform better when substrate is low. Generalists producing both enzymes expand their ecological niche of substrate availability compared to specialists only producing one of the two types. Complementary specialists only co-exist in oligotrophic conditions. We conclude that producing enzymes for specific steps within polymer degradation represents relevant ecological strategies for microbes in decomposer communities. [ABSTRACT FROM AUTHOR]

Plant parasitic nematodes (PPNs) pose a significant threat to global crop productivity, causing an estimated annual loss of US $157 billion in the agriculture industry. While synthetic chemical nematicides can effectively control PPNs, their overuse has detrimental effects on human health and the environment. Biocontrol agents (BCAs), such as bacteria and fungi in the rhizosphere, are safe and promising alternatives for PPNs control. These BCAs interact with plant roots and produce extracellular enzymes, secondary metabolites, toxins, and volatile organic compounds (VOCs) to suppress nematodes. Plant root exudates also play a crucial role in attracting beneficial microbes toward infested roots. The complex interaction between plants and microbes in the rhizosphere against PPNs is mostly untapped which opens new avenues for discovering novel nematicides through multi-omics techniques. Advanced omics approaches, including metagenomics, transcriptomics, proteomics, and metabolomics, have led to the discovery of nematicidal compounds. This review summarizes the status of bacterial and fungal biocontrol strategies and their mechanisms for PPNs control. The importance of omics-based approaches for the exploration of novel nematicides and future directions in the biocontrol of PPNs are also addressed. The review highlighted the potential significance of multi-omics techniques in biocontrol of PPNs to ensure sustainable agriculture. [ABSTRACT FROM AUTHOR]

Higher cost of production and functioning efficiency are the two most important aspects of cellulolytic enzymes, as they directly affect the bioconversion of cellulosic waste into fermentable sugars. Thus, the current study aims to investigate the production of cellulolytic enzymes from low-cost waste biomass for use in the sustainable hydrolysis of biomass to yield fermentable sugars. Since coconut waste is a major contributor to biodegradable waste, two different parts of coconut, including the hard shell of coconut (CS) and the fibers of the shell (FS), have been used for enzyme production as feedstock. Further, enzyme production has been carried out on co-fermentative and acid-pretreated coconut substrates (CS and FS) at different quantities using mixed bacterial cultures. Following this, a crude enzyme with a maximum 20 U/gds FPA, 62 U/gds BGL, and 167 U/gds EG has been produced by mixed Bacillus cultures under co-fermentation of 0.5 % acid-pretreated CS and FS substrates at a quantity of 5:5 (g:g) at 35 °C and pH 5.0. The crude enzyme showed its thermal stability for 16 h at 50 °C and released ~34 g/L of sugars from the hydrolysis of untreated FS biomass in 24 h. This work may have significant applications in the area of biomass-based biorefining as well as waste management. [ABSTRACT FROM AUTHOR]