Antisperm antibodies (ASA) have been implicated in reproductive failure in cows. Present study investigated 58 crossbred cows, of which 38 (normal-cows, NC, n = 16; repeat-breeder-cows, RBC, n = 22) were used for ASA analyses and fertility evaluation, while subsequent bacteriological component included additional 20 cows. ASA levels were assessed from maiden to conceptional-estrus using mixed-antiglobulin reaction (MAR-IgG and MAR-IgA) tests and ELISA, and candidate spermatozoal-bacterial protein pairs were assessed for sequence and three-dimensional structural similarity. MAR-IgG and MAR-IgA levels were significantly lower during conceptional-estrus than during maiden-estrus in both NC and RBC cows, whereas differences between NC and RBC at same estrus stage were less pronounced, indicating that ASA levels were closely associated with conception status than with fertility classification. Receiver operating characteristic analysis based on cow-level measurements showed that MAR-IgG and MAR-IgA discriminated conceptional from non-conceptional status, with area under the curve values of 0.799 and 0.806, respectively. Head-bound spermatozoa represented predominant antibody binding, suggesting that sperm head antigens constitute major ASA targets. Bacillus spp., Escherichia coli and Staphylococcus spp. were predominant bacterial isolates recovered from the genital tract. Sequence and structural analyses of previously identified cross-reactive sperm and bacterial proteins revealed substantial peptide-level similarity and structural-overlap, and structural-superimposition produced low root mean square deviation values, indicating close structural similarity between sperm and bacterial proteins. Collectively, these findings indicate that lower ASA levels are associated with successful conception and support molecular mimicry between genital bacterial and sperm proteins as a plausible mechanism contributing to reproductive immunoinfertility in cows.

Freezing is widely used for microbial preservation; however, it promotes ice crystal formation, which may compromise cellular integrity. Given the variability among cryopreservation protocols used in laboratories and reported in the literature, this study evaluated microbial responses to successive freeze-thaw cycles using different glycerol concentrations in Luria-Bertani (LB) broth and two storage temperatures. Escherichia coli, Staphylococcus aureus, Bacillus subtilis, and Saccharomyces cerevisiae were selected as representatives of a Gram-negative bacterium, a Gram-positive bacterium, a spore-forming bacterium, and a yeast, respectively. Microorganisms were cryopreserved at -20 °C or -70 °C with 10%, 20%, 35%, or 50% glycerol and evaluated over nine successive freeze-thaw cycles. Viability was assessed by loop inoculation recovery and total viable cell counts determined by surface plating. Repeated freeze-thaw cycles significantly affected microbial viability, with responses varying among the evaluated species. E. coli and S. aureus remained stable throughout storage, whereas B. subtilis showed a progressive decline and S. cerevisiae exhibited variable responses. Storage at -70 °C showed a trend toward greater cell viability, although the overall effect of temperature was not significant. Glycerol concentration did not significantly affect microbial survival. A positive correlation was observed between loop inoculation recovery and microbial load, indicating that higher numbers of viable cells increased the likelihood of successful recovery. These findings demonstrate that microbial survival during cryopreservation depends primarily on species-specific characteristics rather than glycerol concentration, highlighting the importance of tailoring preservation protocols to different microorganisms.

One of the most significant diseases affecting mango production is anthracnose, which severely impacts yield and quality. In this study, Bacillus velezensis GX0002980, a strain isolated from the Guangxi Damingshan National Nature Reserve, and its volatile organic compounds (VOCs) exhibited strong antifungal activity against Colletotrichum fructicola, the causal agent of anthracnose. A total of 33 VOCs were identified by GC-MS. Antifungal assays using partitioned Petri dishes revealed seven VOCs with inhibitory activity, among which 2-ethylhexanol showed the greatest effect. Observations utilizing microscopy indicated that C. fructicola exposed to 2-ethylhexanol (2-EH) exhibited swollen, deformed, intertwined, and fractured hyphae with visible perforations. Fluorescent staining further confirmed that 2-EH disrupted the cell wall and cell membrane structure, while also inducing elevated mitochondrial reactive oxygen species (ROS) levels. RNA-seq analysis of C. fructicola exposed to 2-EH revealed multiple differentially expressed genes (DEGs) enriched in metabolic pathways related to the cell wall and membrane, as well as a significant downregulation of genes encoding key enzymes in the TCA cycle and energy metabolism. Collectively, our findings indicate that 2-EH inhibits C. fructicola by disrupting cell wall integrity, damaging the cell membrane and its permeability, suppressing energy metabolism, impairing the mitochondrial respiratory chain, and inducing ROS accumulation. Experiments conducted on harvested mango fruits indicated that 2-EH significantly delayed the development of anthracnose. Our study reveals that 2-EH effectively controls mango anthracnose. We further elucidate the underlying mechanism, showing that both B. velezensis GX0002980 and 2-EH directly inhibit C. fructicola.

Given the grave risk posed by intestinal cryptosporidiosis to vulnerable populations, the current research focused on a new therapeutic avenue. Olibanum (OL) extract and probiotic Bacillus clausii (B. clausii) and their combination were evaluated against Cryptosporidium in vivo in immunosuppressed mice via parasitological, ultrastructural, biochemical, and histopathological analysis. Liquid chromatography-mass spectrometry (LC-MS) analysis of OL revealed the predominance of incensole isomers in its chemical composition. Regarding oocyst count in stool, the highest percentage of oocyst reduction was achieved after combined therapy (98.4%) on the 19th day post-infection, followed by B. clausii-treated group (87.6%), then the OL-treated group (87%). Similar ultrastructural alterations were noticed by scanning electron microscopy (SEM) following treatment by both OL and B. clausii, ranging from shrunken oocysts to severely deformed ones with extensive pits or protrusions. Nonetheless, their combination resulted in complete distortion of the oocysts, leading to their rupture. Biochemically, both OL and B. clausii treatment, either alone or in combination, provoked a decrease in the serum MDA levels, together with a corresponding rise in the mean levels of GSH. Concerning the histopathological findings, the best results were achieved following the combined OL and B. clausii treatment, which has restored villus architecture and remarkably ameliorated detrimental intestinal inflammation and goblet cell count. Finally, immunohistochemical analysis of the lymphocytic population of the intestinal villi revealed a statistically significant rise in the CD4+ /CD8+ ratio after treatment with either OL, B. clausii or their combination, which signals their proficient use for this therapeutic endeavour.

Essential oils (EO) from Piper marginatum Jacq. exhibit biological activities dependent on chemical compositions, which vary mainly due to environmental factors. This study investigated the seasonal and regional variation in the chemical composition and antimicrobial activity of EO from P. marginatum leaves collected in three Brazilian regions across four seasons. Sixty compounds were identified, primarily terpenoids and phenylpropanoids. Multivariate analyses revealed seasonal variations and distinguished the Northeast region EO, which contained the isomers pipermargine (3.38%-14.56%) and 1,3,5-trimethoxy-2-[(Z)-prop-1-enyl]benzene (13.47%-14.87%)-reported for the first time in EO. The Central-West winter EO exhibited the broadest antimicrobial spectrum, with strong activity against Candida albicans (MIC 0.5 mg mL-1) and Bacillus subtilis (MIC 0.5 mg mL-1), and a bacteriostatic effect against Staphylococcus aureus. All EO inhibited Escherichia coli, with the Northeast winter EO showing the strongest activity (MIC 0.25 mg mL-1). This work highlights the importance of studying the chemical and biological variability of P. marginatum EO for potential applications.

Microbial bioelectrocatalysis demands more than electron-conducting surfaces-it demands living microenvironments that hydrate, protect, and nourish whole-cell biocatalysts. This biological imperative remains unaddressed by conventional electrode design. Here, we fundamentally reframe microbial biobattery architecture through living habitat engineering, drawing inspiration from the human small intestine-a biological interface evolutionarily optimized to sustain dense, metabolically active microbial communities through high-surface-area villi, mucus-mediated hydration, and short-path nutrient exchange. We translate these principles into spore-programmed conductive hydrogel pillar arrays, in which dormant Bacillus subtilis endospores are embedded within poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)-poly(vinyl alcohol)/reduced graphene oxide hydrogel villi that simultaneously serve as microbial reservoirs, bioelectrochemical scaffolds, and electron-harvesting conduits. Upon nutrient contact, spores germinate on demand into electroactive cells. This villi topology delivers an 8.3-fold volumetric power density enhancement (8.04 to 66.45 µW cm[-] [3]) over planar controls under volume-matched conditions. A 24-device geometry matrix uncovers a coupled radius-height design rule, with peak single-villus power of 8.35 µW at optimal dimensions. Conformable villi patches demonstrate nutrient-triggered electricity generation in a simulated pipe environment using a wastewater-mimicking nutrient/electrolyte solution, while a separate self-powered array achieves spatially resolved bioelectrochemical sensing. This work establishes living habitat engineering as a transformative paradigm for activatable, architecture-programmed, and potentially shelf-stable microbial biobatteries.

This study reports the complete genome sequence of Bacillus velezensis strain S-LA5, isolated from Leucas aspera in Bangladesh. Oxford Nanopore sequencing yielded a 4.1-Mbp genome (46.5% GC) in a single contig, predicted to encode traits for nutrient acquisition, plant growth promotion, and biocontrol, underscoring its potential in sustainable agricultural disease management.

We report the draft genome of Bacillus altitudinis MSH-24 isolated from rhizosphere soil of Nypa fruticans in Bangladesh. Illumina NovaSeq sequencing generated a 3.9 Mb assembly (41.08% GC) in 22 contigs, revealing genes associated with possible iron acquisition, stress tolerance, sporulation, and germination, highlighting the strain's environmental adaptability and metabolic versatility.

The Bacillus subtilis ytrGABCDEF operon has been implicated in various cellular processes, including antibiotic and cold stress adaptation, cell wall synthesis, autolysis, sporulation, biofilm formation, motility, competence, and acetoin utilization. Yet, how these different observations fit together and the precise function of the operon remain enigmatic. In addition to its function, its topology is also uncertain. Early studies proposed a single YtrBCDEF ATP-binding cassette (ABC) transporter, while more recent studies showed evidence of two distinct ABC transporters, YtrB2CD and YtrE2F2. Here, we phenotypically characterized diverse ytr deletion mutants overexpressing or lacking the whole operon or parts thereof. Unexpectedly, we found a distinct population heterogeneity in ytr mutants that constitutively express either the whole operon or parts thereof. These strains displayed a substantial subpopulation of non-growing cells with measurably decreased cell length and width ("small cells"). This phenotype was most prevalent during adaptation from slow to fast growth and was exacerbated by cold. In mutants expressing an incomplete operon, small cells eventually underwent cell lysis. Taken together, our results suggest a role of the operon in controlling cell size, growth arrest, and autolysis of distinct subpopulations during growth phase transitions and temperature shifts.IMPORTANCEBacillus subtilis is a crucial bacterial model organism with considerable importance to fundamental and applied microbiology, frequently used as a model in bacterial cell biology and physiology and as a production host for various industrial applications. Despite being one of the best-characterized microbes, the B. subtilis genome still contains many genes and operons of unknown or poorly characterized function. The ytrGABCDEF operon has been the subject of a number of studies, yet neither its function nor the structure of the encoded proteins has so far been conclusively elucidated. Here, we provide new insight into the function of this operon that reconciles previous observations and suggests new directions for the further characterization of the structure-function relationship of the Ytr protein complexes.

Abiotic stresses such as drought and salinity represent major constraints to global crop productivity, necessitating innovative strategies for enhancing plant resilience. As a critical regulator of root system architecture, auxin (specifically indole-3-acetic acid (IAA)) functions as a vital cross-kingdom signaling molecule that mediates dynamic interactions between plants and auxin-synthesizing rhizosphere microorganisms. This review explores the role of auxin as a cross-kingdom signaling molecule mediating interactions between plants and the rhizosphere microbiome. Auxin-producing plant growth-promoting rhizobacteria (PGPR) such as Pseudomonas, Bacillus, and Azospirillum can modify root system architecture by stimulating lateral root formation, root hair development, and root elongation. These structural changes enhance soil exploration, improving water and nutrient acquisition under stress conditions. In addition, root exudates released by plants recruit beneficial microbial communities, establishing a feedback loop that stabilizes plant-microbe interactions in the rhizosphere. While previous studies have largely treated plant hormonal signaling and rhizosphere ecology as separate domains, this review bridges these silos by proposing the Auxin-Rhizomicrobiome-Root Architecture (ARRA) model; an integrative framework demonstrating how microbial hormone production and plant signaling networks jointly program adaptive root traits under climate stress. Ultimately, the ARRA framework provides a conceptual and practical blueprint for deploying auxin-producing bioinoculants and engineered rhizomicrobiome consortia, offering a scalable strategy to enhance crop resilience and sustainable food security under accelerating climate scenarios.

The present study demonstrates the successful green biosynthesis of a manganese oxide-selenium nanocomposite (MnO2-Se NC) using watermelon peel waste extract, providing a sustainable approach for valorizing agro-industrial waste into a multifunctional nanomaterial. The biofabricated nanocomposite was characterized by UV-Vis, XRD, FTIR, DLS and TEM analysis. TEM analysis revealed predominantly spherical nanoparticles with an average size of approximately 55 nm, while UV-Vis spectra displayed two distinct absorption peaks at 266 and 300 nm, confirming successful nanocomposite formation. The MnO2-Se NC exhibited potent antibacterial activity, with MIC values ranging from 3.9 to 31.25 µg ml[-1] and MBC values between 15.62 and 125 µg ml[-1]. The highest efficacy was observed against Bacillus subtilis (MIC = 3.9 µg ml[-1]), whereas comparatively lower activity was recorded against Pseudomonas aeruginosa (MIC = 31.25 µg ml[-1]), with MBC/MIC ratios of 2-4 indicating a bactericidal mode of action. In addition, the nanocomposite demonstrated promising antifungal activity, with MIC/MFC values of 31.25/62.5 µg ml[-1] against Candida albicans and 125/500 µg ml[-1] against Aspergillus brasiliensis, suggesting greater effectiveness against yeast than filamentous fungi. Furthermore, the MnO2-Se NC showed strong larvicidal and adulticidal activity against Culex pipiens, with significantly lower LC50 and LC90 values (5.6-7.0 ppm) compared to the crude watermelon peel extract (66-100 ppm). These findings indicate enhanced toxicity and efficacy of the bimetallic nanocomposite at substantially lower concentrations. In conclusion, the findings highlight the considerable multifunctional potential of watermelon peel-derived MnO2-Se NC as a sustainable antimicrobial and vector-control agent. The combined biological activities, together with the use of an abundant agricultural waste resource for synthesis, support its future development as an environmentally friendly nanomaterial for biomedical and mosquito-management applications.

Tuberculosis (TB), caused by Mycobacterium tuberculosis, remains a major global health challenge, particularly in low- and middle-income countries. The Bacillus Calmette-Guérin (BCG) vaccine, developed from attenuated Mycobacterium bovis (M. bovis) and introduced in 1921, is the only licensed vaccine for TB prevention. Although BCG provides strong protection against morbid forms of pediatric TB, its efficacy against adult pulmonary TB is variable. Emerging evidence indicates that BCG exerts broader immunological effects beyond TB prevention, including non-specific immune protection mediated through trained immunity. BCG-induced trained immunity induces epigenetic reprogramming of innate immune cells which enhances host defense against heterologous pathogens. Advances in pharmacological biotechnology, including recombinant BCG platforms, genetic modification, and novel delivery systems, have demonstrated improved antigen presentation, durability of immune memory, and expanded clinical utility. Beyond TB, BCG remains a cornerstone immunotherapy for non-muscle-invasive bladder cancer and shows promising immunomodulatory potential in autoimmune diseases such as type 1 diabetes and multiple sclerosis. While adverse effects are generally mild, they tend to be more pronounced in immunocompromised individuals. This review examines the historical development, biotechnological production, immunological mechanisms, and expanding therapeutic applications of BCG. We synthesized findings on strain variability, manufacturing processes, and immune responses, highlighting the induction of T helper 1 (Th1)-mediated cellular immunity through interferon gamma (IFN-γ) and interleukin-12 (IL-12), macrophage activation, and granuloma formation. Overall, BCG represents both a critical public health intervention and a model system for advancing immune-based therapies.

Bacillus cereus is a spore-forming environmental bacterium and a common cause of foodborne illness, yet its population-level determinants are poorly characterised. We analysed 1,223 notified cases from the 229 districts of the Republic of Korea, 2011 to 2024; models used the 223 contiguous districts (3,122 district-years). Crude incidence was 3.7-fold higher in rural than urban districts, with a warm-season peak. With no spatial autocorrelation (Moran's I =  -0.005, p = 0.51), incidence was modelled with a Bayesian zero-inflated negative-binomial model with independent district and random-walk year effects, which outperformed the negative-binomial model and was well calibrated (ΔDIC ≈50, mid-PIT 0.500 against 0.494). Adjusting for demographic, environmental, healthcare and socioeconomic covariates, pasture land was associated with higher incidence (incidence-rate ratio 1.75, 95% credible interval 1.07 to 2.94), and in-area medical expenditure (0.55, 0.38 to 0.78), influenza-vaccination uptake (0.72, 0.53 to 0.96) and fiscal independence (0.66, 0.45 to 0.95) with lower incidence. In stratified models, household groundwater wells predicted higher rural incidence (1.89, 1.24 to 2.96) and the elderly-population rate higher urban incidence (1.47, 1.06 to 2.04). These exploratory findings are consistent with agricultural and private-water environments contributing to the rural excess of B. cereus.