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Zinc oxide, manganese dioxide, and silicon dioxide nanoparticles were individually tested for managing the bacterial leaf spot disease complex of beetroot (Beta vulgaris L.) caused by Meloidogyne incognita and Pseudomonas syringae pv. aptata. The combined presence of both pathogens resulted in significant reductions in plant growth and photosynthetic pigments while increasing proline contents more than either pathogen alone. Foliar application of nanoparticles significantly improved plant growth, chlorophyll, carotenoid, and proline levels in infected plants. Among the treatments, zinc oxide nanoparticles had the most pronounced positive effects followed by silicon dioxide and manganese dioxide nanoparticles. Zinc oxide nanoparticles also significantly reduced root galling, nematode population, and disease indices. Principal component analysis highlighted the distinct influence of each nanoparticle on disease management with zinc oxide nanoparticles proving the most effective. [ABSTRACT FROM AUTHOR]

Chaetoceros muelleri and Isochrysis zhanjiangensis, known for their rapid reproduction, small size, and rich nutritional content, are commonly used as feed microalgae in aquaculture. This study aimed to sterilize these microalgal species and assess the effects of antibiotics on their algal cell density. Phycospheric bacteria were isolated and identified using the spread plate method and 16S rDNA sequencing, and antibiotic susceptibility tests were conducted using four antibiotics: ampicillin, streptomycin, kanamycin, and gentamicin sulfate. A sterile system was established for C. muelleri using ampicillin, streptomycin, and gentamicin, and for I. zhanjiangensis using kanamycin, ampicillin, and streptomycin. Based on the results, antibiotics with sterilization effects were selected and added to the algal cultures. Their effects on cell density were evaluated during a six-day co-culture. Ampicillin and streptomycin effectively inhibited bacteria associated with C. muelleri, initially increasing algal cell density but later causing a decline. For I. zhanjiangensis, kanamycin and ampicillin were effective, with kanamycin significantly promoting growth throughout the cycle, achieving a 36.92% higher cell density on day six (p < 0.05). [ABSTRACT FROM AUTHOR]

This study compared the performance of three microalgae-based techniques, namely, microalgae monoculture, microalgae co-culture with activated sludge, and microalgae-Ganoderma lucidum S395-2 endophytic bacteria co-culture, for concurrent biogas slurry purification and biogas upgrading. Effects of microalgae species, algae treatment technologies, and exogenous addition of 5-deoxystrigol (5-DS) on strains growth and photosynthesis within different microalgae-based treatment technology systems, as well as the purification effects were studied. Microalgae co-cultured with G. lucidum-bacterium significantly improved the photosynthetic capacity, biomass, nutrient removal efficiency, and biogas conversion rate. The Tetradesmus obliquus-G. lucidum-bacterium consortium with 5-DS at 10-11 M exhibited highest purification efficiency, with the a removal of 87.63 ± 8.51% chemical oxygen demand (COD), 89.76 ± 8.49% total nitrogen and 88.62 ± 8.53% total phosphorus from the biogas slurry and the removal of CO2 in the biogas was 76.59 ± 7.36%. [ABSTRACT FROM AUTHOR]

Antibiotic therapy has been a common method for treating bacterial infections over the past century, but with the rise in bacterial resistance caused by antibiotic abuse, better control and more rational use of antibiotics have been increasingly demanded. At the same time, a journey to explore alternatives to antibiotic therapies has also been undertaken. Chitosan and its derivatives, materials with good biocompatibility, biodegradability, and excellent antibacterial properties, have garnered significant attention, and more and more studies on chitosan and its derivatives have been conducted in recent years. In this work, we aim to elucidate the biological properties of chitosan and its derivatives and to track their clinical applications, as well as to propose issues that need to be addressed and possible solutions to further their future development and application. [ABSTRACT FROM AUTHOR]

Theophylline, a rare xanthine alkaloid, has recently gained more interest in molecular and synthetic biology research due to its high selectivity, strong affinity to its aptamer, cost-effectiveness, availability, and non-toxicity. Despite its non-toxic nature, it is however crucial to establish the threshold limit of its application across different organisms, along with the minimum amount necessary for biotechnological applications. In the current study, various theophylline application methods were investigated at the diverse developmental stages of the model plant Nicotiana tabacum L., exponential growth phases of the bacterium Escherichia coli, and microalga Chlamydomonas reinhardtii. The growth behavior showed that while both plants and bacteria absorbed theophylline, the microalgae demonstrated a higher tolerance, suggesting a probable inefficient uptake of the substance into the cells or metabolization of it within the cell. Accordingly, C. reinhardtii, E. coli, and in vitro–grown tobacco explants showed relative tolerance to theophylline, respectively. Regarding the experiments done with tobacco, a range of theophylline tolerance between 1.5 and 2.5 mM was observed in different in vitro tissues with root development showing more sensitivity than seed germination or shoot regenerations. Remarkably, the greenhouse-grown tobacco plants could tolerate up to 15 mM theophylline when irrigated with the solution. Based on the analysis of the molecular metabolic processes, theophylline exposure did not remarkably affect the total RNA and protein qualities, and also the profiles of two main plastid membrane lipids, in treated tobacco. These findings on theophylline application in three different model organisms offer valuable insights into the protocols for the biological and biotechnological use of this agent. [ABSTRACT FROM AUTHOR]

A major factor limiting the biodegradation of organofluorine compounds has been highlighted as fluoride anion toxicity produced by defluorinating enzymes. Here, two highly active defluorinases with different activities were constitutively expressed in Pseudomonas putida ATCC 12633 to examine adaption to fluoride stress. Each strain was grown on α‐fluorophenylacetic acid as the sole carbon source via defluorination to mandelic acid, and each showed immediate fluoride release and delayed growth. Adaptive evolution was performed for each recombinant strain by serial transfer. Both strains adapted to show a much shorter lag and a higher growth yield. The observed adaptation occurred rapidly and reproducibly, within 50 generations each time. After adaption, growth with 50–70 mM α‐fluorophenylacetic acid was significantly faster with more fluoride release than a preadapted culture due to larger cell populations. Genomic sequencing of both pre‐ and postadapted strain pairs revealed decreases in the defluorinase gene content. With both defluorinases, adaption produced a 56%–57% decrease in the plasmid copy number. Additionally, during adaption of the strain expressing the faster defluorinase, two plasmids were present: the original and a derivative in which the defluorinase gene was deleted. An examination of the enzyme rates in the pathway suggested that the defluorinase rate was concurrently optimised for pathway flux and minimising fluoride toxicity. The rapid alteration of plasmid copy number and mutation was consistent with other studies on microbial responses to stresses such as antibiotics. The data presented here support the idea that fluoride stress is significant during the biodegradation of organofluorine compounds and suggest engineered strains will be under strong selective pressure to decrease fluoride stress. [ABSTRACT FROM AUTHOR]

Pathogenicity test was conducted of three beetroot (Beta vulgaris) cultivars using five different inocula of Meloidogyne incognita and Pseudomonas syringae pv. aptata. Plant growth parameters, chlorophyll and carotenoid contents were reduced significantly over control when 2000 or more second stage juveniles (J2) of M. incognita or 10.0 mL or more P. syringae pv. aptata per kg soil were inoculated in cultivar Rosy Red 555 and Ruby Queen while in Red Express 505, 4000 or more J2 of M. incognita or 20.0 mL or more P. syringae pv. aptata caused significant reductions. A significant increase in proline in Rosy Red 555 and Ruby Queen was observed when 2000 or more J2 of M. incognita or 10.0 mL or more P. syringae pv. aptata were inoculated while in Red Express 505, 4000 or more J2 of M. incognita or 20 mL or more P. syringae pv. aptata caused significant increase. Galling and nematode population was increased with the increase in inoculum level of M. incognita. Bacterial leaf spot indices caused by P. syringae pv. aptata was also increased with the increase in inoculum level of bacterial pathogen. Leaf spot indices were recorded 1–5 scale in different cultivars. [ABSTRACT FROM AUTHOR]

Xylella fastidiosa is one of the most dangerous plant‐pathogenic bacteria globally, affecting various host species. Plum leaf scald (PLS) is the primary disease affecting plum trees in Brazil, with plant eradication efforts significantly increasing in recent years. This study aims to elucidate the disease dynamics and its vector in three monitored orchards from 2010 to 2015 and associate the pattern of pathogen dispersal with mechanical pruning. The incidence was lower in Porto Amazonas, starting at 0% and reaching 14% after 5 years. In contrast, the orchards in Araucaria and Palmeira showed an initial incidence around 5% in the first year, exceeding 80% by the end of the study. Sharpshooter leafhoppers, the vectors, were collected at ground and plant canopy level during the last 3 years. In 2013, more leafhoppers were found near the ground, but their numbers equalized across heights in the following years. Kernel smoothing revealed spatial dependence, and an autologistic model indicated an aggregated infection pattern with increased PLS risk for neighbouring plants. The border effect at the epidemic's onset was linked to pathogen entry via external vectors. The disease's progression along rows was attributed to effective mechanical pathogen transmission through pruning. Therefore, in regions with several summer prunings, it is recommended to sanitize pruning shears to prevent pathogen transmission. Constant monitoring and control of the vector are essential for effective disease management. [ABSTRACT FROM AUTHOR]

This study investigated the in vitro antimicrobial and anthelmintic effect of copper nanoparticles (CuNPs) against the bacterium Aeromonas hydrophila, the monogeneans Dactylogyrus minutus, Dactylogyrus extensus, Gyrodactylus cyprini, and the cestode Schyzocotyle acheilognathi, as well as their toxicity to Cyprinus carpio Koi. In the antimicrobial in vitro test, the inhibition zone method and minimum inhibitory concentration (MIC) were performed. In order to determine the time and efficacy of monogenean parasite mortality, the parasites were exposed to CuNP concentrations of 20, 50, 100, 150, 200, and 300 mg L−1, and a control group with tank water and one with copper sulphate pentahydrate (CuSO4.5H2O) at a concentration of 0.3 mg L−1, performed in triplicate. The parasites were observed every 10 min for 300 min, and mortality was recorded. For the cestodes, parasites were immersed in CuNP concentrations of 50, 100, 150, and 300 mg L−1. At the end of the in vitro tests, the anthelmintic efficacy of each treatment was calculated. To assess the tolerance and toxicity in fish, they were exposed to CuNP concentrations of 0.6, 1.25, 2.5, 5, 10, 20, and 50 mg L−1 for 12 h. The MIC demonstrated that CuNPs effectively inhibited the growth of A. hydrophila up to a dilution of 12,500 mg L−1 and showed an inhibition zone of 14.0 ± 1.6 mm for CuNPs. The results of anthelmintic activity showed a dose‐dependent effect of concentration for both groups of parasites, with the most effective concentration being 300 mg L−1 in 120 min. In the toxicity test, the carps showed tolerance to lower concentrations. The study indicated that CuNPs were effective against the studied pathogens. However, it proved to be toxic to fish at high concentrations. The use of low concentrations is recommended still requires further investigation. [ABSTRACT FROM AUTHOR]

This review aimed to identify newly discovered bacteria from individuals with periodontal/peri-implant diseases and organize them into new clusters (GF-MoR complexes) to update Socransky's complexes (1998). For methodological development, the PCC (Population, Concept, Context) strategy was used for the focus question construction: "In patients with periodontal and/or peri-implant disease, what bacteria (microorganisms) were detected through laboratory assays?" The search strategy was applied to PubMed/MEDLINE, PubMed Central, and Embase. The search key terms, combined with Boolean markers, were (1) bacteria, (2) microbiome, (3) microorganisms, (4) biofilm, (5) niche, (6) native bacteria, (7) gingivitis), (8) periodontitis, (9) peri-implant mucositis, and (10) peri-implantitis. The search was restricted to the period 1998–2024 and the English language. The bacteria groups in the oral cavity obtained/found were retrieved and included in the GF-MoR complexes, which were based on the disease/condition, presenting six groups: (1) health, (2) gingivitis, (3) peri-implant mucositis, (4) periodontitis, (5) peri-implantitis, and (6) necrotizing and molar–incisor (M-O) pattern periodontitis. The percentual found per group refers to the number of times a specific bacterium was found to be associated with a particular disease. A total of 381 articles were found: 162 articles were eligible for full-text reading (k = 0.92). Of these articles, nine were excluded with justification, and 153 were included in this review (k = 0.98). Most of the studies reported results for the health condition, periodontitis, and peri-implantitis (3 out of 6 GF-MoR clusters), limiting the number of bacteria found in the other groups. Therefore, it became essential to understand that bacterial colonization is a dynamic process, and the bacteria present in one group could also be present in others, such as those observed with the bacteria found in all groups (Porphyromonas gingivalis, Tannarela forsythia, Treponema denticola, and Aggregatibacter actinomycetemcomitans) (GF-MoR's red triangle). The second most observed bacteria were grouped in GF-MoR's blue triangle: Porphyromonas spp., Prevotela spp., and Treponema spp., which were present in five of the six groups. The third most detected bacteria were clustered in the grey polygon (GF-MoR's grey polygon): Fusobacterium nucleatum, Prevotella intermedia, Campylobacter rectus, and Eikenella corrodens. These three geometric shapes had the most relevant bacteria to periodontal and peri-implant diseases. Specifically, per group, GF-MoR's health group had 58 species; GF-MoR's gingivitis group presented 16 bacteria; GF-MoR's peri-implant mucositis included 17 bacteria; GF-MoR's periodontitis group had 101 different bacteria; GF-MoR's peri-implantitis presented 61 bacteria; and the last group was a combination of necrotizing diseases and molar–incisor (M-I) pattern periodontitis, with seven bacteria. After observing the top seven bacteria of all groups, all of them were found to be gram-negative. Groups 4 and 5 (periodontitis and peri-implantitis) presented the same top seven bacteria. For the first time in the literature, GF-MoR's complexes were presented, gathering bacteria data according to the condition found and including more bacteria than in Socransky's complexes. Based on this understanding, this study could drive future research into treatment options for periodontal and peri-implant diseases, guiding future studies and collaborations to prevent and worsen systemic conditions. Moreover, it permits the debate about the evolution of bacterial clusters. [ABSTRACT FROM AUTHOR]

Introduction: This study aimed to identify the pathogen responsible for leaf blight in Cyclocodon lancifolius, investigate its biological characteristics, and identify effective synthetic fungicides. Additionally, this study examined changes in physiological and biochemical indices of leaves following pathogen infection and screened biocontrol bacteria that inhibit the pathogen growth, providing a scientific basis for preventing and managing leaf blight in C. lancifolius. Methods: Pathogens were isolated from the interface of healthy and infected leaf tissues and identified through morphological and molecular biological methods. Amplification and sequencing of three genomic DNA regions--internal transcribed spacer region, translation elongation factor 1-a, and glyceraldehyde-3-phosphate dehydrogenase of ribosomal DNA--were performed, followed by the construction of a phylogenetic tree. The biological characteristics of pathogens under various temperature and pH conditions and different nitrogen and carbon sources were analyzed using the mycelial growth rate method. The antifungal effects of 13 chemical agents were evaluated using the poisoned medium method and mycelial growth rate method. Changes in physiological and biochemical indicators post-infection were also assessed. An antagonistic experiment was conducted to screen for biocontrol bacteria. Results: A total of 29 potential pathogenic strains were isolated from infected leaf tissues, with Koch's Postulates confirming Stemphylium lycopersici as a key pathogen causing the disease. Growth analysis of S. lycopersici revealed optimal growth at 20°C and pH 6, with lactose or maltose serving as the most suitable carbon source and histidine as the preferred nitrogen source. Among the 13 synthetic fungicides tested, strain DHY4 exhibited the greatest sensitivity to 400 g/L flusilazole. Significant differences (p < 0.05) were observed in superoxide dismutase, phenylalanine ammonia-lyase, peroxidase, polyphenol oxidase, catalase, and malondialdehyde levels between treated and control groups 3 days post-inoculation. The biocontrol strain DYHS2, identified as a strain of Bacillus subtilis, demonstrated an inhibition rate of 51.80% against S. lycopersici in dual-culture experiments and showed a relative inhibition rate of 78.82% in detached leaf assays. Discussion: These findings provide valuable insights into the newly identified causal agent of leaf blight in C. lancifolius and its biological characteristics, underscoring the potential of B. subtilis DYHS2 and synthetic fungicides such as flusilazole as effective disease management strategies. [ABSTRACT FROM AUTHOR]

[Objective] To study the microbial diversity and the microbial community composition of bucket chicken at different processing. [Method] The V1-V9 region of 16S rRNA of the bacteria in the bucket chicken samples were sequenced by the PacBio full-length highthroughput sequencing technology. [Result] The 67 287 effective sequences and 2 300 OTU were obtained. There were some differences in the bacterial communities of the bucket chicken in different processing stages. A total of 15 bacterial phylum were obtained and the dominant bacteria are Proteobacteria, Bacteroidetes and Actinobacteria, Firmicutes, Deinococcus-Thermus, Verrucomicrobia; at the genus level, a total of 250 bacterial genus were obtained, the dominant bacteria genus were Pseudomonas, Acinetobacter, Staphylococcus, Brochothrix, Mesorhizobium, Janthinobact erium, Flavobacterium, Shewanella, Kaistella, Psychrobacter; at the species level, a total of 621 bacterial species were obtained, and the dominant species were Sediminibacterium magnilacihabitans, Bradyrhizobium sp 011516665, Pseudomonas fragi, Macrococcus caseolyticus, Shewanella baltica. [Conclusion] The microbial communities in the three samples of recooked bucket chicken, 12-hour bucket chicken and soup obtained in the same processing environment were similar, but there are some differences in relative abundance. The dominant bacterial composition of fresh bucket chicken produced at another processing site and fresh chicken was different from other samples. [ABSTRACT FROM AUTHOR]

Abstract Purpose Rot disease caused by Fusarium poses a formidable threat to the growth of saffron (Crocus sativus L.), resulting in substantial damage to both yield and quality. It is paramount to delve into the root causes of rot disease in saffron to optimize both yield and quality. Existing preventive and treatment modalities have exerted deleterious effects on corms and the natural environment. Consequently, the quest for efficacious and eco-friendly methods such as biological control agents has become an urgent imperative. Methods The disparate distribution of microbial communities between rhizospheric microorganisms and saffron serves as the foundational exploration for uncovering the underlying causes of rot disease. Samples from various saffron organs and rhizosphere soil were gathered, and the sequencing data from the microbial communities were interpreted using 16S rRNA and ITS gene sequencing methods. This facilitated an in-depth examination of the composition and changes of microorganisms in both healthy and diseased saffron plants. Results The findings indicated rot disease reduced the abundance and diversity of microorganisms in saffron, and the fungal co-occurrence networks were less stable and their communities were more sensitive to rot disease than the bacterial community. Fusarium was the predominant genus in diseased samples, accounting for 99.19% and 89.77% of the communities in diseased leaves and corms. With corms and leaves displaying heightened susceptibility to infection compared to other plant organs. Some of the beneficial bacterial taxa enriched in the diseased plants were also identified in networks, they showed an antagonistic relationship with Fusarium, suggesting a potential for these bacteria to be used in biologically based control strategies against rot disease. These insights could prove invaluable for the development of biocontrol agents aimed at combating this plant ailment. Conclusion These findings significantly advance our understanding of saffron-microbiome interactions and could provide fundamental and important data for improving saffron yield and quality in the process of sustainable development.

Summary: The gastrointestinal tract may contribute to the regulation of systemic inflammation and skin diseases due to the balance between the pathogenic, opportunistic, and beneficial bacterial species it contains. External supplementation of beneficial bacteria, besides its known positive effect in the treatment of digestive system diseases, also has different favorable effects such as accelerated wound healing, suppression of inflammation, lower infection risk, and reduced antibiotic requirement. It has been reported that oral use of probiotics may be effective in the treatment of skin diseases such as acne, psoriasis, and atopic dermatitis. Furthermore, topical administration of probiotics may create a positive bacterial balance, eliminate pathological conditions, and thus have a favorable impact on the management of skin diseases. Interest in the effect of the skin microbiome and topical probiotics in the treatment of skin diseases has increased recently. Herein, 21 clinical studies and a case report in the PubMed database on the use of topical probiotics in dermatological diseases were evaluated. [ABSTRACT FROM AUTHOR]

This letter considers the possibility of using the optical trap to study the structure and function of the microbial flagellum. The structure of the flagellum of a typical gram-negative bacterium is described in brief. A standard mathematical model based on the principle of superposition is used to describe the movement of an ellipsoidal microbial cell in a liquid medium. The basic principles of optical trapping based on the combined action of the light pressure and the gradient force are briefly clarified. Several problems related to thermal damage of living microscopic objects when the latter gets to the focus of a laser beam are shortly discussed. It is shown that the probability of cell damage depends nonlinearly on the wavelength of laser radiation. Finally, the model systems that would make it possible to study flagella of the free bacteria and the ones anchored or tethered on the surface of a solid material are discussed in detail. [ABSTRACT FROM AUTHOR]

Purpose: Rot disease caused by Fusarium poses a formidable threat to the growth of saffron (Crocus sativus L.), resulting in substantial damage to both yield and quality. It is paramount to delve into the root causes of rot disease in saffron to optimize both yield and quality. Existing preventive and treatment modalities have exerted deleterious effects on corms and the natural environment. Consequently, the quest for efficacious and eco-friendly methods such as biological control agents has become an urgent imperative. Methods: The disparate distribution of microbial communities between rhizospheric microorganisms and saffron serves as the foundational exploration for uncovering the underlying causes of rot disease. Samples from various saffron organs and rhizosphere soil were gathered, and the sequencing data from the microbial communities were interpreted using 16S rRNA and ITS gene sequencing methods. This facilitated an in-depth examination of the composition and changes of microorganisms in both healthy and diseased saffron plants. Results: The findings indicated rot disease reduced the abundance and diversity of microorganisms in saffron, and the fungal co-occurrence networks were less stable and their communities were more sensitive to rot disease than the bacterial community. Fusarium was the predominant genus in diseased samples, accounting for 99.19% and 89.77% of the communities in diseased leaves and corms. With corms and leaves displaying heightened susceptibility to infection compared to other plant organs. Some of the beneficial bacterial taxa enriched in the diseased plants were also identified in networks, they showed an antagonistic relationship with Fusarium, suggesting a potential for these bacteria to be used in biologically based control strategies against rot disease. These insights could prove invaluable for the development of biocontrol agents aimed at combating this plant ailment. Conclusion: These findings significantly advance our understanding of saffron-microbiome interactions and could provide fundamental and important data for improving saffron yield and quality in the process of sustainable development. [ABSTRACT FROM AUTHOR]

Sugarcane is one of Australia's major agricultural industries, with approximately 95% of the crop being grown in Queensland and the remainder in northern New South Wales. In the last decade of the nineteenth century, cane growers in northern New South Wales started to see a new disease that resulted not only in the death of plants but also in difficulties in the extraction of sugar. Theories about the cause abounded, but investigations by the New South Wales vegetable pathologist Nathan Cobb revealed that the disease, previously unknown to the world, was caused by a microbe in the creamy 'gum' that could be commonly found in the vascular tissues of affected stalks. He named the organism Bacillus vascularum (now known as Xanthomonas axonopodis pv. vasculorum). For some time after, the disease was known as 'Cobb's gumming disease of sugarcane'. The Australian bacteriologist Robert Greig-Smith was not convinced that Cobb had conclusively demonstrated that B. vascularum was the culprit, mainly because he did not satisfy Koch's Postulates. However, the American bacteriologist Erwin Frink Smith came to Cobb's rescue when he proved beyond doubt that B. vascularum was to blame. The disease is now known simply as 'gumming disease of sugarcane'. At the start of the decade of 1890, sugarcane growers in southern Queensland and northern New South Wales began to notice a serious disease affecting their crops. American-born Nathan Cobb, who was the New South Wales Government Vegetable Pathologist, discovered that a bacterium, now known as Xanthomonas axonopodis pv. vasculorum , was the cause of the disease. Although others were not convinced that Cobb had conclusively proved that the bacterium was the causal agent, it was for many years known as 'Cobb's gumming disease of cane'. [ABSTRACT FROM AUTHOR]

Simple Summary: There are differences in the cold resistance and anti-freeze compound levels in the two sexes of Pardosa astrigera, driving us to explore the differences in their intestinal microbiome. In this study, intestinal bacterial communities of P. astrigera in winter were compared using 16S rRNA high-throughput sequencing. The results showed significant differences in most alpha diversity indices and the relative abundances of dominant bacteria between males and females. Our research reveals the significant role of sex in shaping the diversity and composition of intestinal bacteria in overwintering P. astrigera. We suggest that Pseudomonas versuta (belonging to Proteobacteria) and Rhodococcus erythropolis (belonging to Actinobacteriota) may have the potential to play key roles in overwintering P. astrigera. Gut microbiota can promote the resistance of host arthropods to low-temperature stress. Female Pardosa astrigera have a lower anti-freeze compound level and weaker resistance to cold temperatures than the males in winter, which implies that their intestinal bacteria may be different during overwintering. This study primarily compared the intestinal bacterial communities between the two sexes of P. astrigera in a temperate region using 16S rRNA gene sequencing. Our findings indicated that the Chao1 and Shannon indices of intestinal bacteria in females were significantly higher than those in males, while the Simpson index in females was significantly lower than that in males. The male intestinal bacterial community was characterized by Proteobacteria and Actinobacteriota at the phylum level and by Pseudomonas and Rhodococcus at the genus level, with total relative abundances of 89.58% and 85.22%, respectively, which were also significantly higher than those in females, whose total relative abundances were 47.49% and 43.68%, respectively. In contrast, the total relative abundances of Bacteroidota and Firmicutes were significantly lower in males (4.26% and 4.75%, respectively) than in females (26.25% and 22.31%, respectively). Noteworthy divergences in bacterial communities were also found through an LEfSe analysis between females and males. Additionally, the results of the PICRUSt2 analysis showed that six out of eleven level-2 pathways related to key metabolic functions were significantly (or marginally significantly) higher in females than males, and five other level-2 pathways were significantly (or marginally significantly) lower in females than males. Our results imply that significant gender differences exist in intestinal bacterial communities of overwintering P. astrigera. We suggest that Pseudomonas versuta (belonging to Proteobacteria) and Rhodococcus erythropolis (belonging to Actinobacteriota) may have the potential to play key roles in overwintering P. astrigera. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB), a grave infectious disease affecting millions globally, is often diagnosed using chest X-rays. For accurate diagnosis, especially for detecting early stage, medical practitioners require the assistance of advanced technologies. In contrast to existing models, which focus largely on TB detection in the images, the proposed work aims to classify the images affecting TB such that an appropriate method can be chosen for accurate chest TB detection in chest X-ray images. Thus, we aim to combine the powerful features of the VGG16 architecture with a convolutional neural network (CNN) for classification purposes. Drawing inspiration from VGG16, known for its effective method of capturing essential image information, we aim to modify VGG16 for feature extraction to identify signs of tuberculosis (TB) in images. For the classification task, we employ a CNN to categorize images impacted by TB. Our proposed technique is evaluated on a standard dataset, demonstrating its superiority over current leading methods in accuracy, recall, and precision. [ABSTRACT FROM AUTHOR]

ABSTRACT Antimicrobials are pivotal in treating bacterial infections. More often than any other class of antimicrobial, antibiotics are a class of antimicrobials used primarily to treat bacterial infections. Thus, both human health and life longevity, as well as the welfare of animals, have greatly improved with the development of antibiotics as a means of treating infectious diseases. Dairy farming is essential to satisfying the world's demand for dairy products. Nevertheless, improper use of antibiotics in dairy farming contributes greatly to the formation of antimicrobial resistance. Moreover, the resulting antimicrobial resistance can be transferred to humans by consuming contaminated dairy products. Therefore, the scientific community has been intensively studying the relationship between dairy farming and antimicrobial resistance since 1983. And, due to the increasing awareness of antimicrobial resistance worldwide, studies on antimicrobial resistance in dairy farming have rapidly increased 89 times in the last twenty years. Today, the development of antimicrobial resistance in dairy farming is among the trending research topics. For this purpose, this study is the first bibliometric approach that aims to guide future studies by revealing all aspects of the studies on this subject between 1983 and 2023.

The magnetotactic bacterium MO-1 possesses a pair of unique flagellar apparatuses. Each apparatus comprises seven flagella and 24 thin fibrils enclosed in a sheath. Using these apparatuses, the cells swim at high speed through solutions, tracing helical trajectories. The mechanism by which MO-1 cells utilize their two flagellar apparatuses to propel the cell body remains unclear. Due to the short length of the flagellar apparatus, direct observation of individual movements under a microscope is technically challenging. In this study, we performed numerical simulations based on the boundary element method to investigate the swimming motility of MO-1 cells. Our cell models successfully reproduced the helical trajectories of active MO-1 cells. The two flagellar apparatuses were positioned at the front and back of the cell body relative to the direction of movement. The cell body was pulled by the anterior flagellar apparatus and pushed by the posterior apparatus. The swimming motion of the cell model exhibited minimal changes near a wall. This unique swimming behavior of MO-1 cells could only be achieved through the rotation of both flagellar apparatuses. Based on the revolution rate of active MO-1 cells, we estimated the rotational speed of the flagellar apparatus to be approximately 1200 s-1. This rapid rotation may result from the tight packing of flagellar filaments within the sheath. Our study elucidates the mechanism by which active MO-1 cells swim in helical trajectories.

Introduction So far, more than 40 different types of alkaloids have been known in poppy (Papaver somniferum L.) as a valuable medicinal plant, the most important of which are morphine, codeine, thebaine, noscapine, and papaverine. The biosynthesis of these alkaloids may be strongly influenced by a variety of biotic and abiotic elicitors. In fact, microbes as biotic elicitors can affect the production of poppy alkaloids. Among them, plant growth promoting rhizobacteria (PGPR) can be noticed, which stimulate and improve plant growth through various mechanisms such as mineral phosphate solubilization, plant hormone production, siderophores secretion, nitrogen fixation, etc. The use of PGPR agents can not only lead to an increase in plant biomass, but simultaneously, due to their role as biotic elicitors, they cause to an increase in the biosynthesis of secondary metabolites in plants. These biotic elicitors target plants’ defense mechanisms and result in triggering a series of metabolic changes throughout the plant. The use of PGPR agents to stimulate the plant to produce secondary metabolites has several advantages: First, in some plants, defensive metabolites are active biological compounds that lead to the induction of food production with high added-value in the plants. Secondly, physiologically, with the increase in the synthesis of secondary metabolites, the resistance of the plant against pathogens also increases. Accordingly, the present study was performed with the aim of investigating the effects of bacterial strains with the ability to solubilize inorganic phosphate as biotic elicitors on the amount of morphine, papaverine, and noscapine alkaloids in P. somniferum. Materials and Methods In this research, the solubility of inorganic phosphate by four bacterial strains including Enterobacter xiangfangensis S2, Pantoea dispersa S7, Pantoea stewartii S25, and Pseudomonas canadensis S36 was evaluated quantitatively using Sperber broth medium. Under greenhouse conditions, the effect of foliar spraying of P. somniferum plants with a suspension of the bacterial strains (108 CFU.ml-1) on the amount of morphine, papaverine, and noscapine in the plants’ capsules, stems, and leaves was investigated. About three weeks after the appearance of capsules in poppy plants, the aerial parts of the plants (stems, leaves, and capsules) were sprayed with the bacterial suspensions. One week after foliar spraying, poppy plants were harvested in order to determine the amount of the desired alkaloids. Three pots were considered for each treatment and there were three poppy plants in each pot. Alkaloids were extracted based on an alcoholic method and detected using HPLC. Morphine and noscapine standards were prepared at a concentration of 1000 μg.ml-1 and papaverine standard at a concentration of 250 μg/ml. Then the mixture was prepared in proportions of 1, 1:50, 1:10, 1:50 and 1:100 and injected into the HPLC set to draw the calibration curve. All the experiments were conducted in a form of completely randomized design with three replications for each treatment (P

The study aimed to assess the prevalence of COVID-19 and Klebsiella spp. coinfection across continents. Conducted following PRISMA guidelines, a systematic review utilized PubMed, Embase, SCOPUS, ScienceDirect, and Web of Science databases, searching for literature in English published from December 2019 to December 2022, using specific Health Sciences descriptors. A total of 408 records were identified, but only 50 were eligible, and of these, only 33 were included. Thirty-three references were analyzed to evaluate the correlation between COVID-19 and Klebsiella spp. infections. The tabulated data represented a sample group of 8741 coinfected patients. The findings revealed notable disparities in co-infection rates across continents. In Asia, 23% of individuals were infected with Klebsiella pneumoniae, while in Europe, the proportion of co-infected patients stood at 15%. Strikingly, on the African continent, 43% were found to be infected with Klebsiella pneumoniae, highlighting significant regional variations. Overall, the proportion of Klebsiella pneumoniae co-infections among COVID-positive individuals were determined to be 19%. Particularly concerning was the observation that 1 in 6 ICU coinfections was attributed to Klebsiella pneumoniae, indicating its substantial impact on patient outcomes and healthcare burden. The study underscores the alarming prevalence of co-infection between COVID-19 and Klebsiella pneumoniae, potentially exacerbating the clinical severity of patients and posing challenges to treatment strategies. These findings emphasize the importance of vigilant surveillance and targeted interventions to mitigate the adverse effects of bacterial coinfections in the context of the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the productive and ruminal microbiological behavior of sheep fed with two levels of dehydrated orange residue (DOR). Design/methodology/approach: Thirty Dorper x Katahdin crossbred male sheep with an average live weight of 22 ± 1.0 kg were distributed in a completely randomized design, with three treatments and ten repetitions. The distribution of treatments was as follows: T1 = diet with 0% DOR (control), T2 = diet with 15% DOR, and T3 = diet with 30% DOR. The variables evaluated were daily weight gain, dry matter intake, feed conversion, ruminal pH, and microbiological analysis. Results: There were no significant differences (p>0.05) in the productive variables due to the inclusion of DOR in the diet. Similarly, the concentration of ruminal microorganisms did not present significant differences between treatments. Study limitations/implications: The study did not include an economic analysis that would demonstrate a reduction in production costs by decreasing the inclusion of maize in the diet. Conclusions: Maize grain is one of the most commonly used cereals as an energy source in sheep feeding; however, it can be replaced by DOR up to 30% without affecting the productive and ruminal microbiological variables in fattening sheep. [ABSTRACT FROM AUTHOR]

Eutrophication of aquatic ecosystems is associated with an increased risk of pathogen infection via increased pathogen growth and host exposure via increased pathogen doses. Here, we studied the effect of nutrients on the virulence of an opportunistic bacterial pathogen of fish, Flavobacterium columnare , in challenge experiments with rainbow trout fingerlings. We hypothesized that removing all nutrients by washing the bacteria would reduce virulence as compared to unwashed bacteria, but adding nutrients to the tank water would increase the virulence of the bacterium. Nutrient addition and increase in bacterial dose increased virulence for both unwashed and washed bacteria. For unwashed bacteria, the addition of nutrients reduced the survival probability of fish challenged with low bacterial doses more than for fish challenged with higher bacterial doses, suggesting activation of bacterial virulence factors. Washing and centrifugation reduced viable bacterial counts, and the addition of washed bacteria alone did not lead to fish mortality. However, a small addition of nutrient medium, 0.05% of the total water volume, added separately to the fish container, restored the virulence of the washed bacteria. Our results show that human-induced eutrophication could trigger epidemics of aquatic pathogens at the limits of their survival and affect their ecology and evolution by altering the dynamics between strains that differ in their growth characteristics. [ABSTRACT FROM AUTHOR]

IntroductionAir flow driven by air-conditioner has a significant impact on the indoor environment, however, the bacterial contamination conditions in the different parts of air-conditioners have not been fully elucidated.MethodsIn this study, we assessed the bacterial pollution in the four parts, including air outlet, filter net, cooling fin and water sink, of ten household air-conditioners quantitatively and qualitatively from Chengdu, southwestern China.ResultsThe microbial cultivation results showed the large total bacterial counts of 5042.0, 9127.6, 6595.1, and 12296.2 CFU/cm2 in air outlet, filter net, cooling fin, and water sink. Furthermore, the sequencing data showed that these four parts displayed different bacterial characteristics. At the level of genus, Caproiciproducens and Acidipropionibacterium were predominant in air outlet. Bacillus, Acinetobacter, Paracoccus, and Corynebacterium were detected as the characteristic bacteria in filter net. For cooling fin, Rhodococcus, Achromobacter, and Nocardioides were the dominant bacteria. The genera of Methylobacterium-Methylorubrum, Brevibacterium, Stenotrophomonas, and Psychrobacter were identified as the bioindicators in water sink. The bioinformatic analysis on the sequencing data illustrated that the bacteria from air-conditioners were associated with metabolic disturbance.DiscussionThis study reveals the distinct bacterial compositions in the different parts of air-conditioner, and provides new clues for the non-negligible bacterial pollution in this common appliance from Chinese households.

In order to investigate the microbial community structure in air of different regions of strong-flavor (Nongxiangxing) Baijiu distillery, the microbial community structure and distribution in air of Baotuquan strong-flavor distillery, outside and inside the brewing workshop were studied by Illumina Miseq high-throughput sequencing technology. The results showed that the microbial community in the air samples of distillery was the richest and the highest in diversity, while the diversity in the brewing workshop was low, indicating that in the long-term brewing process, the microorganisms that were not suitable for the brewing environment were eliminated after continuous screening, and a relatively stable microbial flora suitable for the environment was formed by the appropriate microbial enrichment. A total of 748 bacterial operational taxonomic units (OTUs) and 340 fungal OTUs were detected in all the air samples. A total of 20 bacterial phyla and 289 bacterial genera and 7 fungal phyla and 149 fungal genera were noted. The bacterial community in the air samples of different distillery areas was different, while the similarity of the fungal community was high. Compared with the microorganism in air samples of distillery, the microbial communities inside and outside the brewing workshop were more similar. In addition, the unique microbial communities such as Paracococcus were found in the brewing workshop of strong-flavor Baijiu brewed by mechanization.

This review aimed to identify newly discovered bacteria from individuals with periodontal/peri-implant diseases and organize them into new clusters (GF-MoR complexes) to update Socransky’s complexes (1998). For methodological development, the PCC (Population, Concept, Context) strategy was used for the focus question construction: “In patients with periodontal and/or peri-implant disease, what bacteria (microorganisms) were detected through laboratory assays?” The search strategy was applied to PubMed/MEDLINE, PubMed Central, and Embase. The search key terms, combined with Boolean markers, were (1) bacteria, (2) microbiome, (3) microorganisms, (4) biofilm, (5) niche, (6) native bacteria, (7) gingivitis), (8) periodontitis, (9) peri-implant mucositis, and (10) peri-implantitis. The search was restricted to the period 1998–2024 and the English language. The bacteria groups in the oral cavity obtained/found were retrieved and included in the GF-MoR complexes, which were based on the disease/condition, presenting six groups: (1) health, (2) gingivitis, (3) peri-implant mucositis, (4) periodontitis, (5) peri-implantitis, and (6) necrotizing and molar–incisor (M-O) pattern periodontitis. The percentual found per group refers to the number of times a specific bacterium was found to be associated with a particular disease. A total of 381 articles were found: 162 articles were eligible for full-text reading (k = 0.92). Of these articles, nine were excluded with justification, and 153 were included in this review (k = 0.98). Most of the studies reported results for the health condition, periodontitis, and peri-implantitis (3 out of 6 GF-MoR clusters), limiting the number of bacteria found in the other groups. Therefore, it became essential to understand that bacterial colonization is a dynamic process, and the bacteria present in one group could also be present in others, such as those observed with the bacteria found in all groups (Porphyromonas gingivalis, Tannarela forsythia, Treponema denticola, and Aggregatibacter actinomycetemcomitans) (GF-MoR’s red triangle). The second most observed bacteria were grouped in GF-MoR’s blue triangle: Porphyromonas spp., Prevotela spp., and Treponema spp., which were present in five of the six groups. The third most detected bacteria were clustered in the grey polygon (GF-MoR’s grey polygon): Fusobacterium nucleatum, Prevotella intermedia, Campylobacter rectus, and Eikenella corrodens. These three geometric shapes had the most relevant bacteria to periodontal and peri-implant diseases. Specifically, per group, GF-MoR’s health group had 58 species; GF-MoR’s gingivitis group presented 16 bacteria; GF-MoR’s peri-implant mucositis included 17 bacteria; GF-MoR’s periodontitis group had 101 different bacteria; GF-MoR’s peri-implantitis presented 61 bacteria; and the last group was a combination of necrotizing diseases and molar–incisor (M-I) pattern periodontitis, with seven bacteria. After observing the top seven bacteria of all groups, all of them were found to be gram-negative. Groups 4 and 5 (periodontitis and peri-implantitis) presented the same top seven bacteria. For the first time in the literature, GF-MoR’s complexes were presented, gathering bacteria data according to the condition found and including more bacteria than in Socransky’s complexes. Based on this understanding, this study could drive future research into treatment options for periodontal and peri-implant diseases, guiding future studies and collaborations to prevent and worsen systemic conditions. Moreover, it permits the debate about the evolution of bacterial clusters.

Bacteria regulate their cellular resource allocation to enable fast growth-adaptation to a variety of environmental niches. We studied the ribosomal allocation, growth, and expression profiles of two sets of fast-growing mutants of Escherichia coli K-12 MG1655. Mutants with only three of the seven copies of ribosomal RNA operons grew faster than the wild-type strain in minimal media and show similar phenotype to previously studied fast-growing rpoB mutants. Comparing these two different regulatory perturbations (rRNA promoters or rpoB mutations), we show how they reshape the proteome for growth with a concomitant fitness cost. The fast-growing mutants shared downregulation of hedging functions and upregulated growth functions. They showed longer diauxic shifts and reduced activity of gluconeogenic promoters during glucose-acetate shifts, suggesting reduced availability of the RNA polymerase for expressing hedging proteome. These results show that the regulation of ribosomal allocation underlies the growth/hedging phenotypes obtained from laboratory evolution experiments.

Background and Aim: The rapid development of aquaculture as a major food sector is accompanied by challenges, including diseases that affect tilapia farming worldwide. One such infectious disease caused by Streptococcus agalactiae poses a serious threat to tilapia populations. Probiotics have emerged as a potentially safe preventive measure against S. agalactiae infection. However, antimicrobial resistance from antibiotic-resistant bacteria remains a concern because it can lead to the spread of resistant bacteria and serve as a reservoir of antibiotic-resistant genes in fishes and the surrounding environment. This study aimed to identify candidate probiotic bacteria capable of promoting tilapia growth, providing resistance to S. agalactiae infection, devoid of potential pathogenicity, and free from antibiotic resistance genes. Subsequently, the performance of these probiotic candidates in tilapia was evaluated. Materials and Methods: Lactococcus garvieae, Priestia megaterium, Bacterium spp., Bacillus megaterium, Bacillus subtilis, and Bacillus pumilus were examined to assess their antibacterial properties, hemolytic patterns, and antibiotic resistance genes. We used the specific primers tetA, tetB, tetD, tetE, tetO, tetQ, ermB, and qnrS that were used for antibiotic resistance gene detection. In vivo probiotic efficacy was evaluated by administering probiotic candidates in tilapia feed at a concentration of 1 × 106 colonies/mL/50 g of feed over a 60-day maintenance period. Resistance to S. agalactiae infection was observed for 14 days after the challenge test. Results: Lactococcus garvieae, P. megaterium, and Bacterium spp. were identified as promising probiotic candidates among the bacterial isolates. On the other hand, B. megaterium, B. subtilis, and B. pumilus carried resistance genes and exhibited a β hemolytic pattern, rendering them unsuitable as probiotic candidates. The selected probiotic candidates (L. garvieae, P. megaterium, and Bacterium spp.) demonstrated the potential to enhance tilapia growth, exhibited no pathogenic tendencies, and were free from antibiotic resistance genes. Supplementation with L. garvieae and Bacterium spp. enhanced tilapia resistance to S. agalactiae infection, whereas P. megaterium supplementation showed an insignificant survival rate compared with controls after the challenge test period. Conclusion: Probiotics, particularly L. garvieae, P. megaterium, and Bacterium spp., enhance growth and resistance against S. agalactiae infection, without harboring antibiotic resistance genes. Selecting probiotic candidates based on antibiotic resistance genes is essential to ensure the safety of fish, the environment, and human health.

It is a longstanding and challenging task to develop sustainable environment-friendly and cost-effective corrosion-protection technologies for Mg alloys, especially under marine conditions in which corrosion can normally be significantly accelerated by bacterial activity. However, this paper reports on the corrosion of highly active Mg interestingly inhibited by an algal-symbiotic bacterium Bacillus altitudinis. The corrosion of Mg in the presence of the bacterium drastically reduced by one order of magnitude after 14 days of immersion. This means that the algal-symbiotic bacterium widely available in natural ocean environments may be employed as a green and sustainable inhibitor in the marine industry. Based on electrochemical measurements, surface analyses and microbe experiments, a combined inhibition mechanism is proposed in the paper to interpret the interesting corrosion behavior of Mg.

Ventilator associated pneumonia (VAP) is an infectious disease in clinic with high incidence rate (about 5%-40%) and mortality (about 10%), which is mainly caused by bacteria. At present, the clinical diagnosis of VAP depends on the microbial pathogen diagnosis of sputum samples from the lower respiratory tract. The whole process takes more than 24 hours, which is easy to cause antibiotic misuse and initial treatment failure. In recent years, breath test has received widespread attention due to its non-invasive and convenient characteristics, which attempt to screen and diagnose VAP through analysis of volatile organic compounds (VOCs) in exhalation. Therefore, the research on characterization of VOCs released by VAP pathogens has certain guiding significance for the related breath tests. In this study, the main VAP pathogenic bacteria, including P. aeruginosa, S. aureus, E. coli, E. cloacae, K. pneumoniae, A. baumannii, S. maltophilia, and S. epidermidis, were cultured in tryptic soy broth (TSB) culture medium in vitro, and their headspace samples were obtained after 10 hours of shaking culture. Then, non-targeted detection of VOCs in the headspace was performed by using solid phase microextraction coupled to gas chromatography-mass spectrometry (SPME-GC-MS). It was found that a total of 44 differential amounts of VOCs were released by the 8 strains. Subsequently, these bacterial VOCs were classified and discussed according to ketones, aldehydes, ethers, alcohols, acids, esters, alkanes, benzenes, amides, and (nitrogen-containing) heterocycles. These results showed that there was some consistency in the types of VOCs released by the 8 VAP pathogens, such as the production of dimethyl ether and methyl mercaptan. However, there were some differences in the released VOCs among the different pathogens. For example, only S. aureus released 2-butanone and 3-hydroxy-2-butanone, only E. coli produced acetic acid, only E. coli, S. maltophilia, and S. aureus produced N-nenenebc methylformamide. In addition, K. pneumoniae and P. aeruginosa released dimethyl disulfide (DMDS), and S. maltophilia released dimethyl trisulfide (DMTS). This study systematically reports the similarities and differences in the types of VOCs released by VAP pathogens, providing a reference and foundament for VAP related breath research. In the future, it is expected to achieve rapid and non-invasive screening of VAP through exhalation. However, this study did not detect clinically isolated strains or samples, and it was not possible to verify whether there were any differences in results between standard strains and clinical strains. In future work, it is necessary to consider the characteristic spectra of clinically isolated strains and the landmark VOCs in the exhalation of clinical patients.

The effectiveness of two biological control agents, Chrysoperla carnea (Neuroptera: Chrysopidae) and the entomopatho­genic fungus Beauveria bassiana (Ascomycota: Hypocreales) against nymphs and adults of Neophilaenus campestris (Hemi­ptera: Aphrophoridae) was determined under laboratory conditions. First, different nymphal stages of N. campestris were presented to different larval stages of C. carnea. Second, the effect of the foam produced by N. campestris nymphs on the larvae of C. carnea predation was evaluated. Finally, four concentrations of a wild strain of B. bassiana, BbGEp1, were sprayed on plants in order to determine their lethality for adults of N. campestris. Second and 3rd-instar larvae of green lacewing larvae are capable of capturing and killing 3rd and 5th-instar nymphs of N. campestris. The percentage of 3rd-instar lacewing larvae that killed nymphs was significantly higher than that were killed by second-instar larvae. Second-instar larvae killed significantly more 3rd-instar nymphs than 5th-instar nymphs. Third instar lacewing larvae killed an average (± SEM) of 1.50 ± 0.31 5th-instar nymphs and 2nd-instar larvae killed very few nymphs. Spittlebug foam reduced, but did not prevent predation. The lethality of the entomopathogenic B. bassiana BbGEp1 used against adults of N. campestris was characterized by an LC50 value of 1.61 × 106 conidia/mL and LT50 of 3.63 days at 1 × 107 conidia/mL. The present study provides new and valuable data on the activity of two promising biological control agents of vectors of the bacterium Xylella fastidiosa. Further research is needed to confirm the results presented here and on the cost effectiveness of using these control agents as alternatives to synthetic insecticides for preventing the further spread of X. fastidiosa in Europe.