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Managed colonies of the European honey bee, Apis mellifera, have faced considerable losses in recent years. A widespread contributing factor is a microsporidian pathogen, Nosema ceranae, which occurs worldwide, is increasingly resistant to antibiotic treatment, and can alter the hosts immune response and nutritional uptake. These obligate gut pathogens share their environment with a natural honey bee microbiome whose composition can affect pathogen resistance. We tested the effect of N. ceranae infection on this microbiome by feeding 5 day-old adult bees that had natural, fully developed microbiomes with live N. ceranae spores (40,000 per bee) or a sham inoculation, sterile 2.0 M sucrose solution. We caged and reared these bees in a controlled lab environment and tracked their mortality over 12 d, after which we dissected them, measured their infection levels (gut spore counts), and analyzed their microbiomes. Bees fed live spores had two-fold higher mortality by 12 d and 36.5-fold more spores per bee than controls. There were also strong colony effects on infection levels, and 9% of spore-inoculated bees had no spore counts at all (defined as fed-spores-but-not-infected). Nosema ceranae infection had significant but subtle effects on the gut microbiomes of experimentally infected bees, bees with different infection levels, and fed-spores-but-not-infected vs. bees with gut spores. Specific bacteria, including Gilliamella ASVs, were positively associated with infection, indicating that multiple strains of core gut microbes either facilitate or resist N. ceranae infection. Future studies on the interactions between bacterial, pathogen, and host genotypes would be illuminating.

Fungi are among the most diverse and ecologically important kingdoms in life. However, the distributional ranges of fungi remain largely unknown as do the ecological mechanisms that shape their distributions1,2. To provide an integrated view of the spatial and seasonal dynamics of fungi, we implemented a globally distributed standardized aerial sampling of fungal spores3. The vast majority of operational taxonomic units were detected within only one climatic zone, and the spatiotemporal patterns of species richness and community composition were mostly explained by annual mean air temperature. Tropical regions hosted the highest fungal diversity except for lichenized, ericoid mycorrhizal and ectomycorrhizal fungi, which reached their peak diversity in temperate regions. The sensitivity in climatic responses was associated with phylogenetic relatedness, suggesting that large-scale distributions of some fungal groups are partially constrained by their ancestral niche. There was a strong phylogenetic signal in seasonal sensitivity, suggesting that some groups of fungi have retained their ancestral trait of sporulating for only a short period. Overall, our results show that the hyperdiverse kingdom of fungi follows globally highly predictable spatial and temporal dynamics, with seasonality in both species richness and community composition increasing with latitude. Our study reports patterns resembling those described for other major groups of organisms, thus making a major contribution to the long-standing debate on whether organisms with a microbial lifestyle follow the global biodiversity paradigms known for macroorganisms4,5.

Novel methods for sampling and characterizing biodiversity hold great promise for re-evaluating patterns of life across the planet. The sampling of airborne spores with a cyclone sampler, and the sequencing of their DNA, have been suggested as an efficient and well-calibrated tool for surveying fungal diversity across various environments. Here we present data originating from the Global Spore Sampling Project, comprising 2,768 samples collected during two years at 47 outdoor locations across the world. Each sample represents fungal DNA extracted from 24 m3 of air. We applied a conservative bioinformatics pipeline that filtered out sequences that did not show strong evidence of representing a fungal species. The pipeline yielded 27,954 species-level operational taxonomic units (OTUs). Each OTU is accompanied by a probabilistic taxonomic classification, validated through comparison with expert evaluations. To examine the potential of the data for ecological analyses, we partitioned the variation in species distributions into spatial and seasonal components, showing a strong effect of the annual mean temperature on community composition.

UNLABELLED: A comprehensive microbial surveillance was conducted at NASAs Mars 2020 spacecraft assembly facility (SAF), where whole-genome sequencing (WGS) of 110 bacterial strains was performed. One isolate, designated 179-BFC-A-HST, exhibited less than 80% average nucleotide identity (ANI) to known species, suggesting a novel organism. This strain demonstrated high-level resistance [minimum inhibitory concentration (MIC) >256 mg/L] to third-generation cephalosporins, including ceftazidime, cefpodoxime, combination ceftazidime/avibactam, and the fourth-generation cephalosporin cefepime. The results of a comparative genomic analysis revealed that 179-BFC-A-HST is most closely related to Virgibacillus halophilus 5B73CT, sharing an ANI of 78.7% and a digital DNA-DNA hybridization (dDDH) value of 23.5%, while their 16S rRNA gene sequences shared 97.7% nucleotide identity. Based on these results and the recent recognition that the genus Virgibacillus is polyphyletic, strain 179-BFC-A-HST is proposed as a novel species of a novel genus, Tigheibacillus jepli gen. nov., sp. nov (type strain 179-BFC-A-HST = DSM 115946T = NRRL B-65666T), and its closest neighbor, V. halophilus, is proposed to be reassigned to this genus as Tigheibacillus halophilus comb. nov. (type strain 5B73CT = DSM 21623T = JCM 21758T = KCTC 13935T). It was also necessary to reclassify its second closest neighbor Virgibacillus soli, as a member of a novel genus Paracerasibacillus, reflecting its phylogenetic position relative to the genus Cerasibacillus, for which we propose Paracerasibacillus soli comb. nov. (type strain CC-YMP-6T = DSM 22952T = CCM 7714T). Within Amphibacillaceae (n = 64), P. soli exhibited 11 antibiotic resistance genes (ARG), while T. jepli encoded for 3, lacking any known β-lactamases, suggesting resistance from variant penicillin-binding proteins, disrupting cephalosporin efficacy. P. soli was highly resistant to azithromycin (MIC >64 mg/L) yet susceptible to cephalosporins and penicillins. IMPORTANCE: The significance of this research extends to understanding microbial survival and adaptation in oligotrophic environments, such as those found in SAF. Whole-genome sequencing of several strains isolated from Mars 2020 mission assembly cleanroom facilities, including the discovery of the novel species Tigheibacillus jepli, highlights the resilience and antimicrobial resistance (AMR) in clinically relevant antibiotic classes of microbes in nutrient-scarce settings. The study also redefines the taxonomic classifications within the Amphibacillaceae family, aligning genetic identities with phylogenetic data. Investigating ARG and virulence factors (VF) across these strains illuminates the microbial capability for resistance under resource-limited conditions while emphasizing the role of human-associated VF in microbial survival, informing sterilization practices and microbial management in similar oligotrophic settings beyond spacecraft assembly cleanrooms such as pharmaceutical and medical industry cleanrooms.

Autophagy in eukaryotes functions to maintain homeostasis by degradation and recycling of long-lived and unwanted cellular materials. Autophagy plays important roles in pathogenicity of various fungal pathogens, suggesting that autophagy is a novel target for development of antifungal compounds. Here, we describe bioluminescence resonance energy transfer (BRET)-based high-throughput screening (HTS) strategy to identify compounds that inhibit fungal ATG4 cysteine protease-mediated cleavage of ATG8 that is critical for autophagosome formation. We identified ebselen (EB) and its analogs ebselen oxide (EO) and 2-(4-methylphenyl)-1,2-benzisothiazol-3(2H)-one (PT) as inhibitors of fungal pathogens Botrytis cinerea and Magnaporthe oryzae ATG4-mediated ATG8 processing. The EB and its analogs inhibit spore germination, hyphal development, and appressorium formation in Ascomycota pathogens, B. cinerea, M. oryzae, Sclerotinia sclerotiorum and Monilinia fructicola. Treatment with EB and its analogs significantly reduced fungal pathogenicity. Our findings provide molecular insights to develop the next generation of antifungal compounds by targeting autophagy in important fungal pathogens.

The field of hybrid engineered living materials seeks to pair living organisms with synthetic materials to generate biocomposite materials with augmented function since living systems can provide highly-programmable and complex behavior. Engineered living materials have typically been fabricated using techniques in benign aqueous environments, limiting their application. In this work, biocomposite fabrication is demonstrated in which spores from polymer-degrading bacteria are incorporated into a thermoplastic polyurethane using high-temperature melt extrusion. Bacteria are engineered using adaptive laboratory evolution to improve their heat tolerance to ensure nearly complete cell survivability during manufacturing at 135 °C. Furthermore, the overall tensile properties of spore-filled thermoplastic polyurethanes are substantially improved, resulting in a significant improvement in toughness. The biocomposites facilitate disintegration in compost in the absence of a microbe-rich environment. Finally, embedded spores demonstrate a rationally programmed function, expressing green fluorescent protein. This research provides a scalable method to fabricate advanced biocomposite materials in industrially-compatible processes.

Bacillus subtilis spores are produced inside the cytosol of a mother cell. Spore surface assembly requires the SpoVK protein in the mother cell, but its function is unknown. Here, we report that SpoVK is a sporulation-specific, forespore-localized putative chaperone from a distinct higher-order clade of AAA+ ATPases that promotes the peptidoglycan glycosyltransferase activity of MurG during sporulation, even though MurG does not normally require activation during vegetative growth. MurG redeploys to the forespore surface during sporulation, where we show that the local pH is reduced and propose that this change in cytosolic nanoenvironment abrogates MurG function. Further, we show that SpoVK participates in a developmental checkpoint in which improper spore surface assembly mis-localizes SpoVK, which leads to sporulation arrest. The AAA+ ATPase clade containing SpoVK includes specialized chaperones involved in secretion, cell envelope biosynthesis, and carbohydrate metabolism, suggesting that such fine-tuning might be a widespread feature of different subcellular nanoenvironments. [ABSTRACT FROM AUTHOR]

YabG is a sporulation‐specific protease that is conserved among sporulating bacteria. Clostridioides difficile YabG processes the cortex destined proteins preproSleC into proSleC and CspBA to CspB and CspA. YabG also affects synthesis of spore coat/exosporium proteins CotA and CdeM. In prior work that identified CspA as the co‐germinant receptor, mutations in yabG were found which altered the co‐germinants required to initiate spore germination. To understand how these mutations in the yabG locus contribute to C. difficile spore germination, we introduced these mutations into an isogenic background. Spores derived from C. difficile yabGC207A (a catalytically inactive allele), C. difficile yabGA46D, C. difficile yabGG37E, and C. difficile yabGP153L strains germinated in response to taurocholic acid alone. Recombinantly expressed and purified preproSleC incubated with E. coli lysate expressing wild type YabG resulted in the removal of the presequence from preproSleC. Interestingly, only YabGA46D showed any activity toward purified preproSleC. Mutation of the YabG processing site in preproSleC (R119A) led to YabG shifting its processing to R115 or R112. Finally, changes in yabG expression under the mutant promoters were analyzed using a SNAP‐tag and revealed expression differences at early and late stages of sporulation. Overall, our results support and expand upon the hypothesis that YabG is important for germination and spore assembly and, upon mutation of the processing site, can shift where it cleaves substrates. [ABSTRACT FROM AUTHOR]

Background: Spores are highly resistant dormant cells, adapted for survival and dispersal, that can withstand unfavourable environmental conditions for extended periods of time and later reactivate. Understanding the germination process of microbial spores is important in numerous areas including agriculture, food safety and health, and other sectors of biotechnology. Microfluidics combined with high-resolution microscopy allows to study spore germination at the single-cell level, revealing behaviours that would be hidden in standard population-level studies. Methods: Here, we present a microfluidic platform – the so-called four-conditions microfluidic chemostat (4CMC) – for germination studies where spores are confined to monolayers inside microchambers, allowing the testing of four growth conditions in parallel. This platform can be used with multiple species, including non-model organisms, and is compatible with existing image analysis software. Results: In this study, we focused on three soil dwellers, two bacteria and one fungus, and revealed new insights into their germination. We studied endospores of the model bacterium Bacillus subtilis and demonstrated a correlation between spore density and germination in rich media. We then investigated the germination of the obligate-oxalotrophic environmental bacterium Ammoniphilus oxalaticus in a concentration gradient of potassium oxalate, showing that lower concentrations result in more spores germinating compared to higher concentrations. We also used this microfluidic platform to study the soil beneficial filamentous fungus Trichoderma rossicum, showing for the first time that the size of the spores and hyphae increase in response to increased nutrient availability, while germination times remain the same. Discussion: Our platform allows to better understand microbial behaviour at the single-cell level, under a variety of controlled conditions. While we used it to decipher the responsiveness of soil dwellers' spores, it would also be suitable for other spores from bacteria or filamentous fungi, but also vegetative cells and yeast, and even microbial communities. [ABSTRACT FROM AUTHOR]

Air movement dries surfaces by increasing evaporation and convection, which may prevent mould growth. Cladosporium sp. is used as the test organism (dominant fungi in the envelope of rural houses in hot summer and warm winter areas), and the effect of fans on inhibiting mould growth on building materials is investigated. Surface mould growth on materials was simulated and compared after rain leakage and surface condensation, and spore germination was studied in high humidity, with or without airflow. The results are as follows: (1) Airflow has an evident inhibitory effect on mould growth on wet building materials. This observation was linked to the availability of moisture content in the building materials. (2) Airflow can slow the appearance of visual mould on the material surface. Mould did not appear on the gypsum surface due to the airflow, and mould growth on a wood surface was delayed for about two days. (3) Periodically, spore eluates were examined by electron microscopy to determine the stage of spore germination, and it was found that airflow delayed mould spore germination for about 2–3 days. [ABSTRACT FROM AUTHOR]

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The marine algae Ulva spp. are commonly used as model biofouling organisms. As biofouling studies are primarily conducted using field-collected specimens, factors including species identity, seasonal availability, and physiological status can hinder the replicability of the results. To address these limitations, a protocol was developed for the on-demand laboratory culture and release of Ulva zoospores. The biofouling potential of laboratory-cultured and field-collected Ulva blades was compared using a waterjet. No significant differences were found between field and laboratory-cultured samples in either spore adhesion (before waterjet) or the proportion of spores retained after waterjet exposure. However, there was significant variability within each session type in pre- and post-waterjet exposures, indicating that spore adhesion and retention levels vary significantly among trial runs. In addition, all our laboratory cultures were Ulva Clade C (LPP complex). In contrast, our field samples contained a mix of Ulva Clade C, U. compressa clade I, and U. flexuosa Clade D. This protocol for on-demand production of Ulva spores can improve biofouling research approaches, enables comparison of results across laboratories and regions, and accelerate the development of anti-biofouling strategies. [ABSTRACT FROM AUTHOR]

Protein filaments are ubiquitous in nature and have diverse biological functions. Cryo-electron microscopy (cryo-EM) enables the determination of atomic structures, even from native samples, and is capable of identifying previously unknown filament species through high-resolution cryo-EM maps. In this study, we determine the structure of an unreported filament species from a cryo-EM dataset collected from Bacillus amyloiquefaciens biofilms. These filaments are composed of GerQ, a spore coat protein known to be involved in Bacillus spore germination. GerQ assembles into a structurally stable architecture consisting of rings containing nine subunits, which stacks to form filaments. Molecular dockings and model predictions suggest that this nine-subunit structure is suitable for binding CwlJ, a protein recruited by GerQ and essential for Ca2+-DPA induced spore germination. While the assembly state of GerQ within the spores and the direct interaction between GerQ and CwlJ have yet to be validated through further experiments, our findings provide valuable insights into the self-assembly of GerQ and enhance our understanding of its role in spore germination. Here, the authors structurally characterise a protein filament species composed of the spore coat protein GerQ using cryo-EM. The nine-subunit assembly sheds light on spore biology and hints at an interaction with CwlJ, a protein required for spore germination. [ABSTRACT FROM AUTHOR]

AbstractPteris reptans (Pteridaceae), a native fern of Sri Lanka, has its distribution in India with exclusive limited occurrence in the state of Kerala. The plants from Kerala were examined for their quantity of spores per sporangium, micromorphology using SEM, gametophyte and sporophytic developmental phases. Upon examination, it was discovered that the sporangium of all accessions contained 32 tetrahedral spores with a continuous cingulum and noticeable tubercles on both surfaces. Normal shaped spore frequencies per sporangia ranged erratically from 81% to 95%. The fern exhibited Vittaria-type of spore germination. Gametophytic development followed the Adiantum-type in early stages with further Ceratopteris-type growth. A thorough analysis of antheridial development was done, but throughout the whole investigation, no archegonium was seen. Without any gametic fusion, juvenile sporophytes were produced apogamously on the prothalli. The filamentous stage was retained until the third week after germination and the sporophytes started emerging from the 12th week. After 90–95 days no further sporophytes emerged. Developmental morphology of the sporophyte was studied by observing trends in frond characteristics. The study is the first report on detailed apogamous development of P. reptans and also describes propagation methods for ex-situ multiplication. [ABSTRACT FROM AUTHOR]

AbstractIt is well known that the number of true truffles in the wild is decreasing. The aim of the study was to develop an effective, simple and affordable method of asci disruption to release black truffle spores. It was shown that the spore release can be achieved by different ways, such as mechanical or biological destruction. Mechanical homogenization of fruiting bodies using an immersion blender in tandem with a ball mill was shown to be effective and led to destruction of at least 85% of asci and release of spores. Also, the first approach we applied was the biological method of spore activation performed by African and grape snails. As a result of digestion of truffle fruiting bodies, the spores not only lost their protective shells, but also changed their morphology, which promoted their germination in vitro. The spores obtained using these two methods are capable of forming mycelial hyphae on nutrient media. The results of our study can be used to prepare inoculum of Tuber spp. and to obtain their pure cultures in agriculture. [ABSTRACT FROM AUTHOR]

Pelgipeptins, tridecaptins, and elgicins are among the antimicrobials produced by Paenibacillus elgii. Growth in complex media is commonly applied to obtain lipopeptides from culture's supernatant, but it requires further purification. This study aimed to improve the yield of pelgipeptins and tridecaptins using chemically defined media. The kinetics of antimicrobial lipopeptide yield in chemically defined media were evaluated in P. elgii AC13. Pelgipeptins were detected in the supernatant and the culture pellet, but tridecaptins were mainly associated with cell debris or endospores. We investigated whether removing Ca2+ would impair P. elgii sporogenesis, consequently improving the yield of tridecaptin. The kinetics of both lipopeptides in the presence and absence of Ca2+ were quantitatively and qualitatively evaluated and further correlated with the cell cycle. The impairment of P. elgii AC13 sporogenesis had no effect on tridecaptin production, which remained undetected in the supernatant of the culture. On the other hand, the yield of pelgipeptin in a Ca2+-free medium increased. We showed for the first time that the removal of Ca2+ interrupted the sporogenesis in P. elgii and improved the yield of pelgipeptins. However, Ca2+ absence had no effect on tridecaptin yield, which is possibly degraded or associated with other cell debris components. [ABSTRACT FROM AUTHOR]

The recent discovery of Psilotum × intermedium in Mexico prompted us to reassess the nomenclature of this genus, which has global implications. From an extensive review of nomenclatural types and herbarium specimens, field collections, and a morpho-anatomical analysis, P. nudum and P. flaccidum are treated as accepted species, while P. × complanatum is treated as an interspecific hybrid between them. With this clarification, we specify their main synonymies and designate seven lectotypes (for Bernhardia schiedeana, Psilotum complanatum var. latissimum, P. complanatum var. mexicanum, P. floridanum, P. neocaledonicum, P. triquetrum, P. triquetrum var. gracile) and we select an epitype to give taxonomic support to the hybrid. We provide descriptions, diagnostic comments, and a key for identification of the accepted taxa, and also update the geographical ranges of these three taxa, mainly in Neotropics. [ABSTRACT FROM AUTHOR]

Collections of 36 species of predominantly low elevation Mojave Desert bryophytes from the mid-1990s were assessed for shoot and spore viability. Adult shoots of 16 (of 36) and spores of 14 (of 25) desert species were capable of germination or regeneration after 28 years of continuous desiccation (dark storage) under conditions of ∼23°C and 25–45% relative humidity. Most of the species found viable were in the families Pottiaceae and Grimmiaceae, but also included species of Bryum, Funaria and Ptychostomum. Both shoots and spores from the same collection (patch) of 9 species were viable, including Funaria hygrometrica, regarded in other habitats as an annual species. The oldest collection found viable was from shoots of Grimmia anodon, 29 yr 3 mos. Based on the vigor of shoot and spore regeneration/ germination observed in several species, the records presented here for desiccation longevity should be exceeded in the future. [ABSTRACT FROM AUTHOR]

An advanced approach to the automated assessment of a microscopic slide containing spores is presented. The objective is to develop an intelligent system for the rapid and precise estimation of phytopathogenic spore concentration on microscopic slides, thereby enabling automated processing. The smart microscopy scanning system comprises an electronic microscope, a coordinate table, and software for the control of the coordinate table and image processing. The developed smart microscopy scanning system processes the entire microscope slide with multiple exposed strips, which are automatically determined based on the novel two-stage algorithm. The analysis of trained convolutional neural networks employed for the detection of spore phytopathogens demonstrates high precision and recall metrics. The system is capable of identifying and counting the number of spores of phytopathogenic fungi species Blumeria graminis, Puccinia striiformis, and Pyrenophora tritici-repentis on each exposed strip. A methodology for estimating the spore distribution on a microscopic slide is proposed, which involves calculating the average spore concentration density. [ABSTRACT FROM AUTHOR]

Based on a multi-locus phylogeny of a combined dataset of ITS, LSU, tef1-α, and rpb2 and comprehensive morphological analyses, we describe three new species from the Melanosporum group of genus Tuber and synonymize T. pseudobrumale and T. melanoexcavatum. Phylogenetically, the three newly described species, T. yunnanense, T. melanoumbilicatum and T. microexcavatum, differ significantly in genetic distance from any previously known species. Morphologically, T. yunnanense is distinctly different from its closest phylogenetically related species, T. longispinosum, due to its long shuttle-shape spores (average the ratio of spore length to spore width for all spores (Qm) = 1.74). Tuber melanoumbilicatum differs from the other species in having a cavity and long shuttle-shaped spores (Qm = 1.65). Although T. microexcavatum sampled ascomata have relatively low maturity, they can be distinguished from its closely related species T. pseudobrumale by the ascomata size, surface warts, and spore number per asci; additionally, phylogenetic analysis supports it as a new species. In addition, molecular analysis from 22 newly collected specimens and Genebank data indicate that T. pseudobrumale and T. melanoexcavatum are clustered into a single well-supported clade (Bootstrap (BS) = 100, posterior probabilities (PP) = 1.0); and morphological characteristics do not differ. Therefore, based on the above evidence and publication dates, we conclude that T. melanoexcavatum is a synonym of T. pseudobrumale. By taking into account current knowledge and combining the molecular, multigene phylogenetic clade arrangement and morphological data, we propose that the Melanosporum group should be divided into four subgroups. Diagnostic morphological features and an identification key of all known species in the Melanosporum group are also included. Finally, we also provide some additions to the knowledge of the characterization of T. pseudobrumale, T. variabilisporum, and T. pseudohimalayense included in subgroup 1 of the Melanosporum group. [ABSTRACT FROM AUTHOR]

Coffee cultivation facilitates foreign trade, which is important to the Mexican economy, particularly to the coffee growers of Jilotepec, Veracruz. However, in this region, the soil in which the coffee plants are grown is acidic and has low nutrient availability, making plants susceptible to pests and diseases. In this context, the use of mycorrhizal fungi has gained importance, due to the benefits that they provide in terms of the transport of nutrients and the development of plants, contributing to a reduction in the use of chemical fertilizers. This work aimed to determine the dominant Arbuscular mycorrhizal fungi (AMF) in the soil of coffee farms and evaluate the potential of sorghum as a trap plant for these organisms. As a result, ten morphotypes of AMF were detected in the coffee soil, with Glomus and Acaulospora being the dominant genera. It was found that their presence was related to the pH, clay, organic matter, and total carbon of the soil from the farms. The abundance of spores increased significantly (p < 0.05) between the initial count in the soil and the final count after propagation in the sorghum trap plants. The characteristic structures of mycorrhizal colonization and a high percentage of mycorrhizal colonization of the roots of the trap plants (Sorghum vulgare) were observed at 120 days after sowing. It is concluded that Glomus sp1, Glomus sp2, Glomus sp3, Glomus sp4, Rhizophagus clarus, and Acaulospora scrobiculata are the dominant morphotypes in the considered coffee plantation soils and that sorghum has high potential for favoring the propagation of native AMF through increasing their abundance and favoring high mycorrhizal colonization. [ABSTRACT FROM AUTHOR]

Mangroves, despite thriving at the fringes of habitat tolerance in coastal regions, stand out as one of the world's most highly productive ecosystems. This study delves into the remarkable symbiotic relationship between mangroves and arbuscular mycorrhizal fungi (AMF). Specifically, it assesses seasonal diversity in six true mangrove species and four associated species, situated in Henry's Island, Bakkhali, India. Spore density and root colonization were examined across different seasons. The highest spore density was observed in Heritiera fomes (a timber-producing mangrove) during the post-monsoon season, followed by pre-monsoon and monsoon periods. Root colonization was notably prominent in Ceriops tagal (Indian mangrove), Bruguira gymnorrhiza (Oriental mangrove), and Sonneratia alba (flowering evergreen mangrove) during both pre- and postmonsoon seasons. This study unveiled a rich fungal diversity, with a total of 60 AMF species belonging to 13 genera. Among these, the genus Glomus emerged as the dominant group, with species such as G. deserticola along with another genus Rhizophagus intraradics displaying widespread distribution. Notably, Glomus consistently ranked as the most prevalent genus throughout the year, indicating its remarkable adaptability and strong dispersal capacity in both true and associate mangrove plant species. This research sheds light on the seasonal dynamics of AMF associations in mangrove ecosystems, emphasizing the significance of Glomus as a key player in this symbiotic relationship. These findings contribute to our understanding of the ecological intricacies within mangrove habitats and highlight the adaptability of certain AMF genera to varying environmental conditions. [ABSTRACT FROM AUTHOR]

Species within the Bacillus cereus sensu lato group, known for their spore‐forming ability, are recognized for their significant role in food spoilage and food poisoning. The spores of B. cereus are adorned with numerous pilus‐like appendages, referred to as S‐ENAs and L‐ENAs. These appendages are thought to play vital roles in self‐aggregation, adhesion, and biofilm formation. Our study investigates the role of S‐ENAs and L‐ENAs, as well as the impact of various environmental factors on spore‐to‐spore contacts and the interaction between spores and vegetative cells, using both bulk and single‐cell approaches. Our findings indicate that ENAs, especially their tip fibrillae, play a crucial role in spore self‐aggregation, but not in the adhesion of spores to vegetative cells. The absence of L‐BclA, which forms the L‐ENA tip fibrillum, reduced spore aggregation mediated by both S‐ENAs and L‐ENAs, highlighting the interconnected roles of S‐ENAs and L‐ENAs. We also found that increased salt concentrations in the liquid environment significantly reduced spore aggregation, suggesting a charge dependency of spore‐spore interactions. By shedding light on these complex interactions, our study offers valuable insights into spore dynamics. This knowledge can inform future studies on spore behaviour in environmental settings and assist in developing strategies to manage bacterial aggregation for beneficial purposes, such as controlling biofilms in food production equipment. [ABSTRACT FROM AUTHOR]

The fern independent gametophytes that can maintain populations by vegetative reproduction without conspecific sporophytes have been considered an unusual phenomenon found in some epiphytic or epilithic species of Hymenophyllaceae, Pteridaceae, Lomariopsidaceae, and Polypodiaceae. By chance, the discovery of mysterious strap-like gametophytes on Izu-Oshima Island, Japan, has led to the hypothesis that Hymenasplenium murakami-hatanakae, a fern species belonging to Aspleniaceae, can also form independent gametophytes. Our investigation revealed gametophyte populations of H. murakami-hatanakae on three islands in the Izu Islands. Based on chloroplast DNA analysis of the gametophyte and sporophyte populations, the gametophytes were found to be maintained by vegetative reproduction without a new supply of spores from sporophytes. A comparison of the surrounding vegetation at the collection sites showed that environmental factors such as light and humidity may influence the maintenance of gametophyte populations. These results clearly show that H. murakami-hatanakae is one of the ferns capable of forming independent gametophytes. This is the first report of independent gametophytes from the suborder Aspleniineae (eupolypod II). The discovery of the independent gametophyte within a phylogenetic lineage previously thought not to form independent gametophytes will provide important insights into the morphological and functional evolution of gametophytes in ferns. [ABSTRACT FROM AUTHOR]

The two most common ecomorphs of giant kelp, Macrocystis pyrifera and Macrocystis integrifolia, exhibit almost no geographic overlap across their range in the temperate waters of North and South America, with few exceptions such as Stillwater Cove, CA, USA. However, in laboratory settings they are able to interbreed. The mechanism for the morphological variation is unknown, and whether these features are genetically fixed or malleable under different environmental conditions is unclear. Our study, for the first time, directly compared the growth, development, and morphological transformations of the two Macrocystis ecomorphs in a common garden experiment. We experimentally tested the influence of local environment on giant kelp morphology by rearing lab‐cultured embryonic sporophytes from spores released by M. pyrifera and M. integrifolia sporophylls collected from multiple individuals at Stillwater Cove, CA. The spores were cultured in three treatments: "pyrifera‐morph" only, "integrifolia‐morph" only, and mixed (50:50 "pyrifera‐morph":"integrifolia‐morph" spores). We outplanted the resultant embryonic sporophytes to concrete blocks installed at 7.5–9 m depth in the ocean and monitored the development of the sporophytes over 5 months. Our findings of distinct differences in morphology between the pyrifera‐treatment and integrifolia‐treatment individuals at multiple stages of development including reproductive adults indicates that the morphological differences between the two ecomorphs are genetically determined rather than environmentally induced. We found that primary stipe length and number of branches can be used as diagnostic traits for distinguishing the ecomorphs prior to the stage when adult sporophyte morphology can be definitively characterized. Additionally, no morphological hybrids were observed in the mixed‐treatment, and ultimately the mixed‐treatment individuals were more often categorized as "integrifolia‐morph"‐like than "pyrifera‐morph"‐like. [ABSTRACT FROM AUTHOR]

Anthrax is a notorious disease of public health importance caused by Bacillus anthracis. The causative agent can also be used as a biological weapon. Spores of these bacteria can sustain extreme environmental conditions and remain viable in soil for decades. Domestic and wild ruminants are highly susceptible to this pathogen, which usually presents as a peracute to acute disease. In humans, cutaneous anthrax is frequent but pulmonary and enteric anthrax are more serious. Humans, animals, and the environment are all involved, making anthrax a perfect target for a One Health approach. The environment plays a key role in disease transmission. At a time when the One Health concept is not mere slogans, collaborative efforts of medical professionals, veterinarians, and environmental scientists will be valuable for the prevention and control of this disease. In this review, we discussed the transmission dynamics of anthrax in the environment, animals, and humans, as well as One Health strategies to control and prevent anthrax. [ABSTRACT FROM AUTHOR]

BACKGROUND: The hard double‐walled structure of Ganoderma lucidum spore powder (GLSP) is difficult for the human body to digest, so it is very important to break the wall of GLSP. In this study, the wall of GLSP was broken by mechanical milling at room temperature (MM‐R) and ultra‐fine grinding at low temperature (UFG‐L), respectively. RESULTS: Compared with MM‐R, UFG‐L could better retain the sporangium powder's morphological and structural integrity. During in vitro digestion, compared with unbroken GLSP, the released amounts of polysaccharides and triterpenes from broken GLSP were significantly increased, and they increased with the increase of specific surface area. The bioaccessibility of polysaccharide and triterpene from unbroken GLSP after the intestinal stage were 29.52% and 5.37%, respectively. The bioaccessibility of polysaccharides and triterpene from broken GLSP by MM‐R after the intestinal phase were 39.73–72.45% and 16.44–24.97%, while those by UFG‐L were 44.53–104.18% and 12.96–32.90%, respectively. CONCLUSION: The active ingredients of broken GLSP showed better digestion and absorption abilities than unbroken GLSP. Moreover, the specific surface area of GLSP by UFG‐L was lower than that by MM‐R, and the bioaccessibility of GLSP by UFG‐L was higher than that by MM‐R. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Fungal diseases are the main factors affecting the quality and production of vegetables. Rapid and accurate detection of pathogenic spores is of great practical significance for early prediction and prevention of diseases. However, there are some problems with microscopic images collected in the natural environment, such as complex backgrounds, more disturbing materials, small size of spores, and various forms. Therefore, this study proposed an improved detection method of GCS-YOLOv8 (Global context and CARFAE and Small detector-optimized YOLOv8), effectively improving the detection accuracy of small-target pathogen spores in natural scenes. Firstly, by adding a small target detection layer in the network, the network's sensitivity to small targets is enhanced, and the problem of low detection accuracy of the small target is effectively improved. Secondly, Global Context attention is introduced in Backbone to optimize the CSPDarknet53 to 2-Stage FPN (C2F) module and model global context information. At the same time, the feature up-sampling module Content-Aware Reassembly of Features (CARAFE) was introduced into Neck to enhance the ability of the network to extract spore features in natural scenes further. Finally, we used an Explainable Artificial Intelligence (XAI) approach to interpret the model's predictions. The experimental results showed that the improved GCS-YOLOv8 model could detect the spores of the three fungi with an accuracy of 0.926 and a model size of 22.8 MB, which was significantly superior to the existing model and showed good robustness under different brightness conditions. The test on the microscopic images of the infection structure of cucumber down mildew also proved that the model had good generalization. Therefore, this study realized the accurate detection of pathogen spores in natural scenes and provided feasible technical support for early predicting and preventing fungal diseases. [ABSTRACT FROM AUTHOR]

The prevalence of Clostridium perfringens spores in the environment is crucial for the pathogenesis of this bacterium because these dormant spores, upon contact with a suitable host, can return to active growth to cause disease. We evaluated the prevalence of C. perfringens spores in the Hail and Qassim regions of Saudi Arabia. Methods: A plating method was used to identify C. perfringens. PCR analyses and DNA sequencing were performed for genotypic characterization of the newly isolated C. perfringens.25 of 300 collected samples were identified as C. perfringens by selecting black colonies on selective media and monitoring b-hemolysis on blood agar plate. PCR analyses showed that all 25 isolates carry a-toxin gene (plc), but not the enterotoxin gene (cpe), further confirming that these isolates are indeed cpe-negative. Genome sequencing found that Saudi isolates are genotypically similar to the American and European isolates; no homologues of toxinotyping genes encoding b-, i-, e- and NetB-toxin were detected in 22 Saudi isolates, with the exception of 3 isolates that carry only e-toxin gene etx. Collectively, our findings suggest that C. perfringens are highly prevalent in the Hail and Qassim environment, with 22 (88%) of 25 isolates are type A and remaining 3 (12%) are type D. [ABSTRACT FROM AUTHOR]

Aims Arbuscular mycorrhizal fungi (AMF) can perform significant functions within sustainable agricultural ecosystems, including vineyards. Increased AMF diversity can be beneficial in promoting plant growth and increasing resilience to environmental changes. To effectively utilize AMF communities and their benefits in vineyard ecosystems, a better understanding of how management systems influence AMF community composition is needed. Moreover, it is unknown whether AMF communities in organically managed vineyards are distinct from those in conventionally managed vineyards. Methods and Results In this study, vineyards were surveyed across the Marlborough region, New Zealand to identify the AMF communities colonizing the roots of different rootstocks grafted with Sauvignon Blanc and Pinot Noir in both conventional and organic systems. The AMF communities were identified based on spores isolated from trap cultures established with the collected grapevine roots, and by next-generation sequencing technologies (Illumina MiSeq). The identified AMF species/genera belonged to Glomeraceae, Entrophosporaceae, and Diversisporaceae. The results revealed a significant difference in AMF community composition between rootstocks and in their interaction with management systems. Conclusions These outcomes indicated that vineyard management systems influence AMF recruitment by rootstocks and some rootstocks may therefore be more suited to organic systems due to the AMF communities they support. This could provide an increased benefit to organic systems by supporting higher biodiversity. [ABSTRACT FROM AUTHOR]

The survival strategy of members of the bacterial genus Actinoplanes is fascinating from morphological and evolutionary perspectives. A brief motile phase is incorporated in the filamentous and resting stages of the life cycle of Actinoplanes missouriensis. Spores either lie dormant or swim under different external conditions. This review presents microscopic observations and molecular genetic analyses of A. missouriensis morphological development. Selected examples of the characterization of developmental genes and their products are also introduced. [ABSTRACT FROM AUTHOR]

Dispersal of reproductive propagules determines recruitment patterns and connectivity among populations and can influence how populations respond to major disturbance events. Dispersal distributions can depend on propagule release strategies. For instance, the bull kelp, Nereocystis luetkeana, can release propagules (spores) from two heights in the water column ("bimodal release"): at the water surface, directly from the reproductive tissues (sori) on the kelp's blades, and near the seafloor after the sori abscise and sink through the water column. N. luetkeana is a foundation species that occurs from central California to Alaska and is experiencing unprecedented levels of population declines near its southern range limit. We know little of the kelp's dispersal distributions, which could influence population recovery and restoration. Here, we quantify how bimodal spore release heights affect dispersal outcomes based on a numerical model specifically designed for N. luetkeana. The model incorporates oceanographic conditions typical of the species' coastal range and kelp biological traits. With bimodal release heights, 34% of spores are predicted to settle within 10 m of the parental alga and 60% are predicted to disperse beyond 100 m. As an annual species, bimodal release heights can facilitate the local regeneration of adults within a source kelp forest while also supporting connectivity among multiple forests within broader bull kelp metapopulations. To leverage this pattern of bimodal spore dispersal in bull kelp restoration management, directing resources toward strategically located focal populations that can seed other ones could amplify the scale of recovery. [ABSTRACT FROM AUTHOR]

In order to evaluate the application potential of tetraconazole in the prevention and control of tobacco powdery mildew, the spore germination method was used to test the toxicity of tetraconazole on spore germination of Golovinomyces tabaci, and its effect on the microscopic morphology of G. tabaci. The pot experiments were conducted to test the control effect of tetraconazole on tobacco powdery mildew in the greenhouse. The results indicated that tetraconazole had a strong inhibitory effect on conidial germination of three G. tabaci strains, and the EC50 values were 0.3422, 0.3561 and 0.4105 μg/mL, respectively. The EC50 values for inhibition of germ tube elongation were 1.7466, 1.3988, and 1.3229 μg/mL, respectively. Microscopic observation results indicated that tetraconazole had no teratogenic effect on conidia, but it could make the primary hyphae thickened and bifurcated. The results of the greenhouse control test showed that after 14 days of treating tobacco seedlings with 4% tetraconazole water emulsion at doses of 1.61, 3.22, and 5.36 g/L, respectively, the protective effect ranged from 76.62% to 95.67%, and the therapeutic effect ranged from 71.42% to 90.91%. [ABSTRACT FROM AUTHOR]

Context: Understanding the movement of bioaerosols, such as spores and pollen, through the atmosphere is important for a broad spectrum of landscape research, including agricultural fungal outbreaks and pollen threats to public health. As spores and pollen can be transported in the air over large distances, the use of aircraft has historically played a role in detecting and mapping their presence in the lower atmosphere. Objectives: We present a simple alternative to costly and specialized aircraft and associated equipment that are typically used in the study of spores and pollen in the atmosphere. Methods: We use 3D printable components and common lab supplies mounted on an uncrewed aircraft (UA). Conveniently, this setup does not require additional electronic components to control collection during flight, using the UA landing gear mechanism instead. Results: We demonstrate that this apparatus can collect fungal spores in the atmosphere and describe potential impacts by the environment and experimental protocol on collection efficiency. These include the effects of: (1) competing airflows from UA rotors, flight trajectories, and wind, (2) flight altitude, and (3) particle size and Petri dish collection medium. Conclusions: Complex biological mechanisms and atmospheric dynamics dictate the release, transport, and deposition of bioaerosols. Economical methods to sample bioaerosols in the lower atmosphere can increase the amount and type of data collected and unlock new understanding. The methodology presented here provides an economical method to sample bioaerosols that can help improve landscape-level understanding of the dispersal of bioaerosols. [ABSTRACT FROM AUTHOR]

Bacillus species, which have two cell-type forms (vegetative cells and spores), demonstrate a variety of probiotic functions in animal feed additives and human nutrition. We previously found that the probiotic effect of Bacillus subtilis S-2 spores with high germination response to L-alanine was specifically enhanced by the L-alanine pretreatment. The germination response of Bacillus is highly associated with the germination receptors of spores. However, how L-alanine-induced germination of spores exerts anti-infectious effect in epithelial cells remains unclear. In this study, we constructed the mutant strain of B. subtilis S-2 with germination receptor gerAA knockout to further explore the role of spore germination in resisting pathogen infection to cells. The differential probiotic effects of B. subtilis S-2 and S-2ΔgerAA spores pretreated with L-alanine were evaluated in intestinal porcine epithelial cells (IPEC-J2) or Caco2 cells infected with enterotoxigenic Escherichia coli (ETEC) or following IL-1β stimulation. The results showed that the germination response of the S-2ΔgerAA spores to L-alanine was significantly reduced. Compared with the S-2ΔgerAA spores, the L-alanine-induced germination of B. subtilis S-2 spores significantly increased the activity of anti-adhesion of ETEC to IPEC-J2 cells and reduced the expression of inflammatory factors and cell receptors. L-alanine induction also significantly promoted the expression of autophagy-related proteins in the B. subtilis S-2 spores. These findings demonstrate that the gerAA germination receptor is essential for the probiotic function of Bacillus spores and that L-alanine treatment promotes the anti-infectious properties of the germinated spores in porcine intestinal epithelial IPEC-J2 cells. The result suggests the importance of germination receptor gerAA in helping spore germination and enhancing anti-infectious activity. The findings in the study benefit to screening of potential Bacillus probiotics and increasing probiotic efficacy induced by L-alanine as an adjuvant. [ABSTRACT FROM AUTHOR]

The green tea catechin epigallocatechin gallate (EGCg) has antimicrobial effects on many bacteria. In this study, we investigated the inhibitory effects of EGCg on Bacillus anthracis spores and vegetative cells. The B. anthracis spores were insensitive to EGCg, but the growth of vegetative cells derived from germinated spores was inhibited by EGCg. Moreover, EGCg decreased the minimum inhibitory concentration of penicillin and meropenem for penicillin-resistant B. anthracis. In the penicillin-resistant B. anthracis strain, the transcription levels of the beta-lactamase genes (bla1 and bla2) decreased significantly following the treatment with 50 µg/mL EGCg. These results suggest that the appropriate application of EGCg may effectively control the penicillin-resistant B. anthracis growth and beta-lactamase production. [ABSTRACT FROM AUTHOR]

Mangroves, despite thriving at the fringes of habitat tolerance in coastal regions, stand out as one of the world’s most highly productive ecosystems. This study delves into the remarkable symbiotic relationship between mangroves and arbuscular mycorrhizal fungi (AMF). Specifically, it assesses seasonal diversity in six true mangrove species and four associated species, situated in Henry’s Island, Bakkhali, India. Spore density and root colonization were examined across different seasons. The highest spore density was observed in Heritiera fomes (a timber-producing mangrove) during the post-monsoon season, followed by pre-monsoon and monsoon periods. Root colonization was notably prominent in Ceriops tagal (Indian mangrove), Bruguira gymnorrhiza (Oriental mangrove), and Sonneratia alba (flowering evergreen mangrove) during both pre- and post-monsoon seasons. This study unveiled a rich fungal diversity, with a total of 60 AMF species belonging to 13 genera. Among these, the genus Glomus emerged as the dominant group, with species such as G. deserticola along with another genus Rhizophagus intraradics displaying widespread distribution. Notably, Glomus consistently ranked as the most prevalent genus throughout the year, indicating its remarkable adaptability and strong dispersal capacity in both true and associate mangrove plant species. This research sheds light on the seasonal dynamics of AMF associations in mangrove ecosystems, emphasizing the significance of Glomus as a key player in this symbiotic relationship. These findings contribute to our understanding of the ecological intricacies within mangrove habitats and highlight the adaptability of certain AMF genera to varying environmental conditions.

It is well known that the number of true truffles in the wild is decreasing. The aim of the study was to develop an effective, simple and affordable method of asci disruption to release black truffle spores. It was shown that the spore release can be achieved by different ways, such as mechanical or biological destruction. Mechanical homogenization of fruiting bodies using an immersion blender in tandem with a ball mill was shown to be effective and led to destruction of at least 85% of asci and release of spores. Also, the first approach we applied was the biological method of spore activation performed by African and grape snails. As a result of digestion of truffle fruiting bodies, the spores not only lost their protective shells, but also changed their morphology, which promoted their germination in vitro. The spores obtained using these two methods are capable of forming mycelial hyphae on nutrient media. The results of our study can be used to prepare inoculum of Tuber spp. and to obtain their pure cultures in agriculture.

Anaerobic fungi (Neocallimastigomycetes) found in the guts of herbivores are biomass deconstruction specialists with a remarkable ability to extract sugars from recalcitrant plant material. Anaerobic fungi, as well as many species of anaerobic bacteria, deploy multi-enzyme complexes called cellulosomes, which modularly tether together hydrolytic enzymes, to accelerate biomass hydrolysis. While the majority of genomically encoded cellulosomal genes in Neocallimastigomycetes are biomass degrading enzymes, the second largest family of cellulosomal genes encode spore coat CotH domains, whose contribution to fungal cellulosome and/or cellular function is unknown. Structural bioinformatics of CotH proteins from the anaerobic fungus Piromyces finnis shows anaerobic fungal CotH domains conserve key ATP and Mg2+ binding motifs from bacterial Bacillus CotH proteins known to act as protein kinases. Experimental characterization further demonstrates ATP hydrolysis activity in the presence and absence of substrate from two cellulosomal P. finnis CotH proteins when recombinantly produced in E. coli. These results present foundational evidence for CotH activity in anaerobic fungi and provide a path towards elucidating the functional contribution of this protein family to fungal cellulosome assembly and activity.

In vitro culture experiments are crucial for studying chemically-mediated interactions in plants. However, the difficulty in distinguishing spores and sporelings of different bryophyte species hinders research on early developmental stages. Here we propose a modification of the sandwich technique, a standard method for studying plant allelopathic, and present a case study using two common mosses. As in the standard sandwich method, we have created a physical barrier using gelled medium, and inoculated spores of Tortula muralis and Syntrichia ruralis in two layers. To assess their intra- and interspecific interactions, we measured the green coverage of the protonemata using image analysis, and the degree of sporeling development using a categorical index. We successfully obtained physically separated sporelings of target and emitters from spores of these two species. The green coverage analysis showed no differences in any of the comparisons. However, the developmental index showed a negative effect of T. muralis on S. ruralis, whereas S. ruralis appeared to promote the development of T. muralis. The method proposed here is successful for culturing moss spores. The two inocula (the emitter and the receiver) are physically separated but the set-up allows the diffusion of water-soluble and volatile substances. For testing interactions at these early stages of the gametophyte, we recommend measuring the degree of development of moss sporelings rather than their coverage. Our results revealed both positive and negative interspecific interactions between T. muralis and S. ruralis sporelings. This supports that positive interactions in bryophytes may be more common than previously thought. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal (AM) fungi can sequester different potentially toxic elements, such as trace elements (TEs), within their structures to alleviate the toxicity for its host plant and themselves. To elucidate the role of AM fungi in TEs immobilization in the rhizosphere of host plants, it is important to know the TEs distribution in AM fungal structures. In the present study, we investigated the distribution and concentration of TEs within extraradical spores and mycelium of the AM fungus Rhizophagus intraradices, collected from the rhizosphere of Senecio bonariensis plants grown in a soil polluted with multiple TEs, by using Particle-Induced X-ray Emission with a micro-focused beam (micro PIXE). This technique enabled the simultaneous micrometric mapping of elements in a sample. The calculated values were compared with those in the polluted substrate, measured by the Wavelength Dispersive X-ray Fluorescence technique. The highest concentrations of Fe, P, Ti, Mn, Cr, Cu and Zn were found in AM fungal spores, where they were accumulated, while extraradical mycelium was enriched in Cu. Finally, we demonstrated that AM fungi can simultaneously accumulate high amounts of different TEs in their structures, thus reducing the toxicity of these elements to its host plant. • Micro PIXE analysis of arbuscular mycorrhizal fungal structures. • Chemical elements distribution maps. • Trace elements association with spores wall and polyphosphate granules. [ABSTRACT FROM AUTHOR]

Coffee cultivation facilitates foreign trade, which is important to the Mexican economy, particularly to the coffee growers of Jilotepec, Veracruz. However, in this region, the soil in which the coffee plants are grown is acidic and has low nutrient availability, making plants susceptible to pests and diseases. In this context, the use of mycorrhizal fungi has gained importance, due to the benefits that they provide in terms of the transport of nutrients and the development of plants, contributing to a reduction in the use of chemical fertilizers. This work aimed to determine the dominant Arbuscular mycorrhizal fungi (AMF) in the soil of coffee farms and evaluate the potential of sorghum as a trap plant for these organisms. As a result, ten morphotypes of AMF were detected in the coffee soil, with Glomus and Acaulospora being the dominant genera. It was found that their presence was related to the pH, clay, organic matter, and total carbon of the soil from the farms. The abundance of spores increased significantly (p < 0.05) between the initial count in the soil and the final count after propagation in the sorghum trap plants. The characteristic structures of mycorrhizal colonization and a high percentage of mycorrhizal colonization of the roots of the trap plants (Sorghum vulgare) were observed at 120 days after sowing. It is concluded that Glomus sp1, Glomus sp2, Glomus sp3, Glomus sp4, Rhizophagus clarus, and Acaulospora scrobiculata are the dominant morphotypes in the considered coffee plantation soils and that sorghum has high potential for favoring the propagation of native AMF through increasing their abundance and favoring high mycorrhizal colonization.

Thermoplastics used to construct a variety of patient medical devices can become contaminated by harmful bacteria. We investigated whether two different Bacillus species recovered from patient radiation therapy thermoplastic masks could similarly contaminate thermoplastic material used to construct patient orthoses (splints). Bacillus bacteria form dormant spores, which have been shown to enhance its attachment to thermoplastics. Bacterial attachment and recovery were examined using an orthotic thermoplastic with an anti-stick coating being compared to uncoated material used in radiation therapy applications. Triplicate sample squares were seeded with a saline suspension of either B. cereus (MAB03F) or B. megaterium (DAB01F) containing a similar number of spores. Squares were subsequently sampled at 1 h, 1 week, 2 weeks, 4 weeks, and 8 weeks. The number of recovered bacteria was counted. Differences in material hydrophobicity were determined by water contact angle analysis. Both Bacillus species attached to each material within 1 h, and their spores were recovered at 8 weeks. However, a decreasing trend in adhesion, over time, was noted to the coated material with an opposite increasing trend in the uncoated material. Decreased Bacillus species spore adhesion to coated material with a lower hydrophobicity suggests a greater potential for spore transfer to patients wearing contaminated orthoses.

In order to clarify the optimal spore production and inoculation methods for watermelon stem blight (Stagonosporosis cucurbitaceae), and to lay a solid foundation for the screening and identification of watermelon stem blight resistant germplasm resources, this article focuses on the spore production and inoculation methods of watermelon stem blight. Two common spore production methods were compared from the aspects of spore production time, spore yield, and spore morphology of stem blight. It was found that the UV induced spore production method had shorter spore production time, more stable spore yield, normal spore morphology, and lower cost compared to the cucumber induced spore production method. Currently, it was the best spore production method for watermelon stem blight. Watermelon resistant and susceptible materials were also inoculated with the methods of inoculum cake in vitro, spot inoculation with live spore suspension, and spray inoculation with live spore suspension, respectively. The three inoculation methods were compared in terms of operation difficulty and accuracy, and it was found that each of the three inoculation methods had advantages and disadvantages. The difference of resistance and susceptibility of watermelon resistant and susceptible materials was obvious after inoculating in vitro with cake inoculation and in vivo spore suspension spot inoculation, while the susceptible materials showed moderate resistance after inoculating in vivo spore suspension spray inoculation. Through comparison, it was found that the in vitro bacterial cake inoculation method and the live spore suspension point grafting method were more reliable, but the disease grading standards of the in vitro bacterial cake inoculation method were not precise enough, and the small differences in resistance between materials were difficult to reflect; the live spore suspension point grafting method had high accuracy, but the operation was complex, time-consuming, and labor-intensive; in vivo spore suspension spray inoculation method was simple in operation, but it was difficult to accurately control the amount of inoculum, and the accuracy was general. Therefore, it was suggested that the live spore suspension spray inoculation method could be used for preliminary screening when identifying the resistance of large quantities of materials to Fusarium wilt, and the live spore suspension spot connection method could be used when identifying the resistance of a small number of materials to Fusarium wilt, and the isolated cake inoculation method could be used as an auxiliary method to further verify the inoculation results. [ABSTRACT FROM AUTHOR]

Clostridioides difficile causes a wide range of intestinal diseases through the action of two main cytotoxins, TcdA and TcdB. Ingested spores germinate in the intestine establishing a population of cells that produce toxins and spores. The pathogenicity locus, PaLoc, comprises several genes, including those coding for TcdA/B, for the holin-like TcdE protein, and for TcdR, an auto-regulatory RNA polymerase sigma factor essential for tcdA/B and tcdE expression. Here we show that tcdR, tcdA, tcdB and tcdE are expressed in a fraction of the sporulating cells, in either the whole sporangium or in the forespore. The whole sporangium pattern is due to protracted expression initiated in vegetative cells by σD, which primes the TcdR auto-regulatory loop. In contrast, the forespore-specific regulatory proteins σG and SpoVT control TcdR production and tcdA/tcdB and tcdE expression in this cell. We detected TcdA at the spore surface, and we show that wild type and ΔtcdA or ΔtcdB spores but not ΔtcdR or ΔtcdA/ΔtcdB spores are cytopathic against HT29 and Vero cells, indicating that spores may serve as toxin-delivery vehicles. Since the addition of TcdA and TcdB enhance binding of spores to epithelial cells, this effect may occur independently of toxin production by vegetative cells. This study shows that the genes coding for the two main toxins produced by Clostridioides difficile are expressed during sporulation and that the toxins associate with the mature spores, which have a cytopathic effect on human intestinal cell lines. [ABSTRACT FROM AUTHOR]

This paper describes a Pennsylvanian lycophyte cone collected from a highway cut along the southbound lanes of U.S. Interstate Highway 24 (I-24) north of Vienna, Illinois (USA) and stratigraphically belonging to the basal Tradewater Formation, under the Reynoldsburg Coal Bed (upper Bashkirian, lowermost Pennsylvanian). The cone is incomplete, more than 135 mm long and 26 mm wide, mainly representing the distal part with a missing base. The in situ spores from the cone represent trilete cingulizonate microspores belonging to the Lycospora brevijuga Group. Based on these spores together with morphological characters, the cone was compared with already existing species and differs sufficiently to warrant establishing a new species, here named Lepidostrobus willardii sp. nov. • Key words: Lepidostrobus, Lycospora, Tradewater Formation, Pennsylvanian, Illinois Basin. [ABSTRACT FROM AUTHOR]

A palynological study of 84 cutting samples from Cape Three Points 1 (CTP-1) well in the Tano basin allows the identification of three biozones based on the First Appearance Datum (FAD) and Last Appearance Datum (LAD) of stratigraphically significant sporomorphs taxa recovery. These are Elateropollenites jardinei - Reyrea polymorphus Zone, Elaterocolpites castelainii - Afropollis jardinus Zone, and Cretacaeiporites polygonalis - Classopollis classoides Zone, which permit an age assignment of early - middle Albian, late Albian - early Cenomanian and late Cenomanian respectively. The diagnostic miospores from the samples are characteristic of the Albian-Cenomanian Elaterate paleofloral Province in a semi-arid to arid climate, with sediments yielding mixed kerogen assemblage which reflects a marginal marine or nearshore environment. Four palynofacies assemblages (P-1 to P-4) and kerogen types identified indicate deposition under marginal dysoxic-anoxic basin (kerogen type III), shelf to basin transition (kerogen type III/II), a distal suboxic-anoxic basin (kerogen type II>I) and distal dysoxic-anoxic shelf (kerogen type II) conditions respectively. Thermal maturity values obtained from colour changes of psilate spore (Deltoidspora, Cyathidites) reveal that samples from P-1 and P-2 are within immature phase and P-3 and P-4 are mature. [ABSTRACT FROM AUTHOR]

Background: Probiotic administration can be an effective treatment against intestinal inflammation. This study aimed to assess the potential effects of spores isolated from probiotic strains Bacillus subtilis natto and Bacillus coagulans Hammer on inflammation induced by lipopolysaccharide (LPS) in human colon epithelial cells in vitro. Materials and Methods: The viability of HT-29 cells treated with spores derived from B. subtilis natto and B. coagulans Hammer (MOI 10, 100, 1000), as well as LPS (10 µg/ml) was assessed. The anti-inflammatory effects of spores were examined on HT-29 cells that were pre-stimulated with LPS. The expression level of IL-6 and TLR4 genes in HT-29 cells was quantified after 24 h using RT-qPCR. Results: There was no significant reduction in the viability of HT-29 cells after exposure to LPS and various MOIs of probiotic spores. Stimulation of HT-29 cells with LPS significantly increased the expression level of IL-6 and TLR4 in comparison to control (P < 0.0001). Spores isolated from both probiotic strains, B. subtilis natto and B. coagulans Hammer, caused a significant reduction in the gene expression of IL-6 and TLR4 in HT-29 cells compared to LPS control (P < 0.0001). Conclusion: The findings of this study suggest that probiotics-derived spores may exert anti-inflammatory effects through interference with the LPS signaling pathway in colon cancer HT-29 cell line. [ABSTRACT FROM AUTHOR]