BMC Microbiology最新文献

{"title":"Combatting biofilm formation of Klebsiella pneumoniae and Bacillus subtilis clinical strains from the oral cavity using biogenic Se-NPs: molecular docking simulation and cytotoxic effects on HepG2 cancer cells.","authors":"Abdullah Yousef, Mohammed Abu-Elghait, Mohamed S Rizk, Marwa Salah Abdel-Hamid, Salem S Salem, Gamal M El-Sherbiny","doi":"10.1186/s12866-025-04142-w","DOIUrl":"10.1186/s12866-025-04142-w","url":null,"abstract":"<p><p>Bacterial biofilms are one of the primary causes of pathogenic activity in the oral environment; they adhere to both natural and artificial oral surfaces, causing cariogenic processes that result in dental decay and significantly reducing the lifespan of dental restoratives and prostheses; they can also affect the tissues surrounding teeth, causing gingival inflammation; persistent biofilms can cause damage to the alveolar bone, which in extreme cases may result in tooth loss; our study aims to isolate clinical isolates that are resistant to multiple drugs, before disarming them by suppressing the formation of biofilms. Klebsiella pneumoniae A11(K. pneumoniae) and Bacillus subtilis A33 (B. subtilis) clinical isolates were determined, and the most potent clinical isolates were identified as the most virulent strains for further investigations using 16 S rDNA PCR sequencing, with accession numbers PP995146 and PP995148 respectively. Synthesized selenium nanoparticles (Se-NPs) were analyzed using FTIR Spectroscopy, UV-Vis Spectroscopy, zeta potential, dynamic light scattering (DLS), X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDX) of the [Se-NPs] solution revealed that it contained 88.49% selenium and 11.51% carbon, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). According to TEM images, the average size of Se-NPs was 45.4 nm, and their shape was nearly spherical. The minimum inhibitory concentration (MICs) of biogenic Se-NPs were 0.25 mg/mL for K. pneumoniaeA11 and 0.125 mg/mL for B. subtilisA33, with inhibition zones of 11-14 mm. Se-NPs significantly reduced biofilm formation at 0.125 and 0.25 mg/mL (p < 0.05), by 85.08% in K. pneumoniae A11 and 75.45% in B. subtilis A33. A synergistic effect with azithromycin was observed, with fractional inhibitory concentration (FIC) values of 0.502 and 0.253, respectively. Molecular interactions showed Se-NPs forming hydrophobic contacts in K. pneumoniae LuxS Synthase (Asp52, Asp132; binding energy - 3.9020 kcal/mol) and B. subtilis AbbA (His3, Met4, Arg5; -4.2489 kcal/mol). Se-NPs had an IC₅₀ of 2.12 ± 0.02 µg/mL on HepG2 cells.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"446"},"PeriodicalIF":4.0,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12278682/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144681991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-host distribution of Rhodococcus equi (Prescottella equi) strains and their phylogenomic clustering.","authors":"Giovanni Ghielmetti, Marc J A Stevens, Sarah Schmitt, Sonja Kittl, Nicole Cernela, Michael Biggel, Bettina Schulthess, Peter M Keller, Jacques Schrenzel, Roger Stephan","doi":"10.1186/s12866-025-04152-8","DOIUrl":"10.1186/s12866-025-04152-8","url":null,"abstract":"<p><strong>Background: </strong>Rhodococcus equi is an intracellular bacterial pathogen that can cause infections in various hosts, including humans and animals. Host-associated virulence plasmids have been identified as key contributors to the pathogenicity of R. equi and potentially play a role in determining the host tropism of the bacteria. The investigation of additional clinical and environmental isolates is likely to provide novel insights into the population structure, infection pathways, and drug resistance of this important pathogen. We combined whole-genome sequencing and antimicrobial-susceptibility testing of 37 selected R. equi isolates from animal, human, and environmental sources, collected in Switzerland over a 21 year period. In addition, we gathered a total of 251 whole-genome sequences and 141 multi-locus sequence (MLST) typing records from public sources. Although large geographical areas are not represented due to missing genomes we used a phylogenetic approach to define diversity patterns, distribution, and host tropism of R. equi.</p><p><strong>Results: </strong>Horse isolates, irrespective of the country of isolation, exhibited distinct sequence types (ST), notably ST-1 and ST-24 among others, and carried the VAPA plasmid, implying a strain-specific affinity for particular plasmid types. Several STs including ST-62 and ST-76 associated with the VAPN plasmid included both human and ruminant isolates from Switzerland, hinting at a potential common infection source. Similarly, isolates from porcine and human sources, documented in various European countries and China, exhibited common ST, including ST-18 and ST-36, and were found to harbour VAPB plasmids upon testing, suggesting potential zoonotic implications.</p><p><strong>Conclusions: </strong>Using a genomic approach we report host-specific strains that serve as carriers of virulence-associated plasmids, indicating an adaptation strategy within distinct R. equi lineages. The existence of shared plasmid profiles between farm animals and humans suggests a common infection source. Our results contribute to an improved understanding of the global genetic diversity of virulent and environmental R. equi strains, which will benefit from additional molecular epidemiological studies including strains from unrepresented geographical areas.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"447"},"PeriodicalIF":4.0,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12278488/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144681992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Differential adaptability of active ammonia-oxidizing bacteria and archaea to nitrogen amendment and fusarium in monocropped banana soils.","authors":"Pingshan Fan, Jawad Ullah, Zhongjun Jia, Yunze Ruan","doi":"10.1186/s12866-025-04162-6","DOIUrl":"10.1186/s12866-025-04162-6","url":null,"abstract":"<p><p>This study examines how intensive agricultural management influences ammonia-oxidizing microbial communities (AOB and AOA) in banana monoculture systems, with implications for nitrogen cycling and soil acidification dynamics. While previous research has documented the impact of synthetic fertilizers and pathogens on microbial populations in agroecosystems, the responses of active AOB/AOA taxa under combined nitrogen and disease stressors remain largely uncharacterized. We employed soil microcosms established from a native forest (Y0), a two-year-old (Y2), and a twelve-year-old (Y12) banana plantation. Treatments included urea amendment, Fusarium oxysporum f. sp. cubense (Foc) inoculation, and their combination. AOB/AOA activity was quantified via ¹³CO₂ DNA stable isotope probing, while community composition was analyzed through high-throughput 16 S rRNA gene sequencing. Our results revealed distinct microbial community patterns across land-use types and treatments. AOB dominated in banana plantation soils, with their abundance significantly increasing (p < 0.05) in the Y12 system compared to Y0. Conversely, AOA were predominant in the forest soil. Urea amendment and Foc co-application synergistically enhanced AOB activity in banana soils, withariant community shifts observed across all microcosms. Specifically, urea addition in Y0 soil promoted Nitrosotaleales 1.1-AOA (20.16%) and Nitrosospira cluster 2AOB (88.23%), whereas co-treatment induced a dominance shift to Nitrosospira cluster 3a (72.12%). In Y2 soils, urea alone supported Nitrosospira cluster 2-AOB (84.53%) and Nitrososphaerales Group 1.1b-AOA (72.4%), while combined amendments further increased Nitrosospira cluster 3a-AOB abundance compared to urea-only treatment. These findings establish that AOB play a critical functional role in nitrogen transformation under intensive cropping systems, with their activity patterns strongly influenced by both fertilization and pathogen stressors.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"445"},"PeriodicalIF":4.0,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12275427/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144667210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Associations between psychological or biological stress indicators and gut microbiota in pregnant women - findings from a prospective longitudinal study.","authors":"Jakub Kreisinger, Šárka Kaňková, Daniela Dlouhá, Jana Ullmann, Kamila Nouzová, Hana Hrbáčková, Lucie Schmiedová, Lea Takács","doi":"10.1186/s12866-025-04146-6","DOIUrl":"10.1186/s12866-025-04146-6","url":null,"abstract":"<p><strong>Background: </strong>The perinatal period has been linked with higher vulnerability to stress and symptoms of depression and anxiety, as well as with dynamic changes in the composition of maternal gut microbiota. While recent studies indicated significant associations between stress, depression, or anxiety, and alterations in gut microbiota in pregnant women, research in this avenue is still emerging, with existing studies often being limited by small sample sizes.</p><p><strong>Method: </strong>We conducted a prospective longitudinal study of 171 women, collecting gut microbiota samples in each trimester of pregnancy and in the early postpartum, questionnaire data (perceived stress via the Perceived Stress Scale, symptoms of depression via the Edinburgh Postnatal Depression Scale, and anxiety via the 6-item State-Trait Anxiety Inventory) twice in each trimester and twice in the early postpartum period, and blood samples for cortisol levels analysis in the first and third pregnancy trimesters. Gut microbiota samples were analyzed by amplicon sequencing of 16S rRNA gene.</p><p><strong>Results: </strong>Perceived stress and symptoms of depression and anxiety showed moderate temporal changes and a high consistency at the individual level over the study period. Cortisol levels rose significantly from the first to the third trimester. There were significant temporal changes in microbiota composition between the first and second trimesters, and between the first and third trimesters. After controlling for false positive findings due to multiple testing, we found no significant associations between stress-related variables (perceived stress, cortisol levels, symptoms of depression and anxiety) and gut microbiota diversity, microbial community composition, or relative abundances of individual bacterial taxa.</p><p><strong>Conclusions: </strong>The present study results contradict previous research that indicated significant associations between emotions and gut microbiota in the perinatal period. Although we cannot provide an ultimate explanation for this discrepancy, we propose it can lie in insufficient control for false positives in the differential abundance analyses in most previous studies.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"442"},"PeriodicalIF":4.0,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12275315/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144667209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of gold nanoparticles and γ-cyclodextrin polymer on physicochemical, antimicrobial, and antibiofilm properties of a novel schiff base derived from dialdehyde cellulose and camphor thiazole-imine.","authors":"Al-Hassan S Mahdy, Entesar A Hassan, Gharieb S El-Sayyad, Hadeer A Taher, Salem E Zayed","doi":"10.1186/s12866-025-03859-y","DOIUrl":"10.1186/s12866-025-03859-y","url":null,"abstract":"<p><p>The present study developed a novel antimicrobial composite based on 2,3-dialdehyde cellulose (DAC), with biocompatible properties and long-term stability. Initially, DAC was synthesized through the periodate oxidation of microcrystalline cellulose, achieving a 61% degree of oxidation. Subsequently, the DAC was successfully modified through the formation of a Schiff base with CTI in the basic medium. The antimicrobial efficacy of the synthesized DAC-CTI was strengthened by the synthesis of Au NPs via a green chemical approach using lemon extract and their subsequent grafting into the DAC-CTI matrix, followed by encapsulation of the produced DAC-CTI/Au nanocomposite into the γ-cyclodextrin ring. The TEM results of DAC-CTI/Au nanocomposite indicated an average Au particle size of 37.4 nm within the nanocomposite. The evaluated samples reveal a positive efficacy against a variety of bacteria, including P. aeruginosa, C. albicans, and S. aureus. Particularly, DAC-CTI/Au NPs/γ-CD exhibited the highest effect on S. aureus (19.0 mm zone of inhibition (ZOI) and 2.5 µg/mL MIC), E. coli (20.0 mm ZOI and 1.25 µg/mL MIC), and C. albicans (18.2 mm ZOI and 2.5 µg/mL MIC). The outcomes achieved open the door to the practical implementation of intriguing compounds in biological fields.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"443"},"PeriodicalIF":4.0,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12275303/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144667211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correlations between gut microbiota and serum metabolomics in patients with neurogenic rosacea.","authors":"Min Li, Jian Fu, Jinyu Wei, Mei Wan, Ling Li, Minmin Kong, Shuguang Chen, Lian Zhang, Aiai Xia, Li Tang, Fei Hao, Jian Li","doi":"10.1186/s12866-025-04173-3","DOIUrl":"10.1186/s12866-025-04173-3","url":null,"abstract":"<p><p>This study aimed to investigate the association between serum metabolomic profiles and the gut microbiota in patients with neurogenic rosacea. We analyzed the serum metabolites and gut microbial composition in 20 patients with neurogenic rosacea and 14 healthy controls. Metabolomic analysis identified 56 differentially abundant metabolites (DAMs), with benzene and substituted derivatives, carboxylic acids and derivatives, and organophosphates being among the most enriched categories. Gut microbiota analysis revealed significant dysbiosis in patients with neurogenic rosacea, characterized by an increased abundance of Lachnospiraceae, Veillonellaceae, and Clostridiaceae, and decreased levels of Prevotellaceae and Bifidobacteriaceae. Spearman's correlation analysis demonstrated significant relationships between specific serum metabolites and gut microbial taxa, including strong positive correlations between 3,4-dihydroxyphenylacetic acid and both Bifidobacterium (r = 0.7307, padj = 9.25e-07) and Lactobacillus (r = 0.6898, padj = 6.39e-06). These findings highlight the complex interactions between metabolic dysregulation and gut microbial imbalances in neurogenic rosacea, suggesting a potential role for the gut-skin axis in its pathophysiology. This study paves the way for future therapeutic strategies targeting both metabolic and microbial dysbiosis to manage neurogenic rosacea.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"441"},"PeriodicalIF":4.0,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12272963/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144658496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Role of laccase and xylanase, with or without ferulic acid esterase-producing Lactiplantibacillus plantarum, on the aerobic stability, microbial composition and in vitro degradability of mulberry silage.","authors":"Ya Su, Qiang Yu, Yulong Xi, Yuanjiang Rong, Yixi Long, Yixiao Xie, Hong Sun, Jun Hao, Fuyu Yang, Yulong Zheng","doi":"10.1186/s12866-025-04165-3","DOIUrl":"10.1186/s12866-025-04165-3","url":null,"abstract":"<p><p>Laccase (L), xylanase (X), and ferulic acid esterase (FAE) act on lignin - carbohydrate complexes. Whether these enzymes, alone or combined, can improve mulberry ensiling and aerobic stability is unclear. This study assessed the effects of L, X, and FAE - producing L. plantarum (LP) on whole - plant mulberry silage's fermentation quality, aerobic stability, and microbial communities during aerobic exposure. After 60 days of ensiling, mulberry silage treated with CK, LP, LX, or M was unsealed for 1, 3, 5, or 7 days for exposure to air. The results indicated that the LP and M treatments decreased mulberry silage pH. The lower aminopeptidase and carboxypeptidase activities in the LP and M treatments might have contributed to the reduced degradation of crude protein (CP) and ammoniacal nitrogen (NH₃-N) content (P < 0.05). Compared with the CK treatment, the addition of LX and M increased the acetic acid (AA) content by 1.49-2.68-fold, indicating greater aerobic stability (P < 0.05), which contributed to maintaining the storage quality of the silages during aerobic exposure. The application of additives to mulberry silage reduced the species richness; specifically, the additive treatments led to an increase in the relative abundance of Kondoa and Lentilactobacillus while decreasing that of Enterococcus and Delftia. Notably, Lentilactobacillus exhibited the capacity to inhibit the growth of other harmful microorganisms and emerged as the dominant genus within the LX group. In conclusion, treatment with the combination of laccase, xylanase, and FAE-producing L. plantarum can serve as an effective method to improve the silage quality and aerobic stability of mulberry.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"439"},"PeriodicalIF":4.0,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12265255/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144648550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antimicrobial resistance and virulence gene profiles of Escherichia coli isolated from poultry farms using One Health perspective in Abeokuta, Nigeria.","authors":"A T Ajibola, M de Lagarde, O E Ojo, S A Balogun, G Vanier, J M Fairbrother, O B Shittu","doi":"10.1186/s12866-025-04135-9","DOIUrl":"10.1186/s12866-025-04135-9","url":null,"abstract":"<p><strong>Background: </strong>Antimicrobial resistant Extraintestinal pathogenic Escherichia coli (ExPEC) includes uropathogenic E. coli (UPEC), the causative agents of urinary tract infections (UTI), neonatal meningitis E. coli (NMEC), implicated in neonatal meningitis in humans, and avian pathogenic E. coli (APEC). Antimicrobial resistant ExPEC infections are associated with economic losses in poultry worldwide. However, few studies have been done on ExPEC in Nigeria.</p><p><strong>Methods: </strong>In order to gain further insight into the presence of antimicrobial resistant ExPEC in poultry and the putative transmission of E. coli isolates from healthy chickens to poultry owners and/or the environment, antimicrobial susceptibility testing (AST) and polymerase chain reaction (PCR) to determine the presence of 5 virulence genes considered as ExPEC predictors were carried out on 71 E. coli isolates from apparently healthy chickens, their handlers and their shared environment, in Abeokuta, Ogun State, Nigeria. In addition, 14 of the 71 isolates were characterized using whole genome sequencing.</p><p><strong>Results: </strong>Regardless of the source, 70.4% of the isolates were multidrug-resistant (MDR) and 66.2% of the isolates were resistant to fluoroquinolones. Only 3 out of the 71 isolates had at least 2 ExPEC predictor genes and the proportion of antimicrobial resistance (AMR) was higher in isolates with at least 1 ExPEC predictor gene. Thirty different resistance determinants were identified from the 14 whole genome sequenced isolates and most of the sequenced isolates harbored plasmid-mediated resistance genes, including aph(3″)-Ib, aph(6)-Id, floR, sul1, sul2, tet(A), and tet(B). Isolates were very diverse, 11 different serotypes and 12 different sequence types being detected in this study. Twenty different replicons were also found, IncF1B being the most frequently detected. Different ExPEC virulent genes and virulence associated genes (VAGs) for iron acquisition, toxin production, invasion and other virulence determinants were detected.</p><p><strong>Conclusions: </strong>Our results suggest that apparently healthy birds carry antimicrobial resistant genes and virulence genes, underlining their possible transmission to humans. The presence of similar ARGs and VAGs in the handlers of birds and their shared environment highlights the importance of using a One Health approach.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"440"},"PeriodicalIF":4.0,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12265224/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144648539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Environmental stressors drive fungal community homogenization and diversity loss in plateau freshwater lakes.","authors":"Kai Fang, Zheng-Quan Zhang, Hong-Wei Shen, Yong-Zhong Lu, Lin Yang, Zong-Long Luo","doi":"10.1186/s12866-025-04144-8","DOIUrl":"10.1186/s12866-025-04144-8","url":null,"abstract":"<p><strong>Background: </strong>Fungi play a crucial role in aquatic ecosystems by driving nutrient cycling, organic matter decomposition, and water purification. However, the diversity and community structure of aquatic fungi, particularly in plateau freshwater lakes, remain underexplored. This study used high-throughput sequencing to investigate fungal communities in three plateau lakes (Chenghai, Erhai, and Lugu) with varying water quality, focusing on how environmental factors shape community composition.</p><p><strong>Results: </strong>Significant differences in fungal α-diversity and community structure were observed across the lakes. Chenghai Lake, with the poorest water quality, exhibited the lowest fungal diversity and a more homogenized community structure. Reduced diversity was associated with elevated salinity, pH, total dissolved solids (TDS), potassium (K), and nitrate (NO₃⁻), while the fungal community structure was influenced by both geographic and physicochemical factors. Saprotrophic fungi were the most predominant functional guild across all lakes. Geographical factors, particularly altitude, positively influenced the richness and abundance of all fungal functional guilds, while most physicochemical factors showed negative associations, with exceptions like NH₃-N and DO. The fungal network in Erhai Lake, characterized by higher complexity and connectivity, showed features consistent with an enhanced capacity for buffering against environmental fluctuations. In contrast, the simpler network structures in Chenghai and Lugu Lakes suggested greater resistance, maintaining stability through reduced sensitivity to environmental change. All three lakes exhibited predominantly positive correlations among fungal species, with Lugu Lake showing the highest proportion, potentially reflecting enhanced cooperative interactions under nutrient-limited conditions.</p><p><strong>Conclusions: </strong>These findings highlight the strong dependence of aquatic fungal communities on environmental conditions, suggesting their potential as bioindicators for water quality. Variations in fungal co-occurrence patterns imply different adaptive strategies across lakes. Further research is needed to validate these findings and explore the broader applicability of fungal networks in environmental health monitoring.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"438"},"PeriodicalIF":4.0,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12261782/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144641848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High temperatures and antibacterial plant additives change the fermentation quality, free amino acids and lactic acid bacteria fermentation type in Caragana Korshinskii silage.","authors":"Tong Zhou, Xingcheng Lei, Yimei Luo, Yangwen Ou, Simin Tian, Yixiao Xie, Yulong Zheng, Hong Sun, Fuyu Yang","doi":"10.1186/s12866-025-04153-7","DOIUrl":"10.1186/s12866-025-04153-7","url":null,"abstract":"<p><strong>Background: </strong>High temperatures cause a significant loss of dominant lactic acid bacteria (LAB) and the proliferation of harmful microorganisms during ensiling. The current study aimed to investigate the effects of tea residue (TR), mugwort (AA), and molasses (CMA) on silage quality, free amino acid content, and the bacterial community of Caragana korshinskii (C. korshinskii) with Lactobacillus plantarum (LP) at 40 °C.</p><p><strong>Results: </strong>Compared to those at the control temperature (25 °C), the concentration of lactic acid and the number of LAB in all treatments decreased with the progression of fermentation at 40 °C; however, the ammoniacal nitrogen (NH₃-N) and propionic acid concentrations increased after 14 days. The levels of 15 free amino acids initially increased and then decreased. The fermentation temperature significantly affected the diversity of the bacterial community, with the community succession transitioning from Lactiplantibacillus to Lactobacillus, Stenotrophomonas_A_615274, Salinivibrio, and other genera during the fermentation process. TR + LP treatment resulted in a 48.9% increase in crude protein content and a 46.4% decrease in NH₃-N content at 40 ℃. LP only and AA + LP treatments elevated acetic acid (HAc) levels and the relative abundance of Lactobacillus while reducing other bacterial diversity at 40 °C.</p><p><strong>Conclusion: </strong>The integration of LAB with plant-derived additives improved the fermentation quality of C. korshinskii silage by decreasing both NH₃-N production and harmful bacterial abundance under high-temperature conditions. The TR + LP treatment group increased the nutritional quality of C. korshinskii silage. The LP and AA + LP treatment groups had a bacteriostatic effect, but no significant effect on improving nutritional quality in C. korshinskii silage.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"25 1","pages":"437"},"PeriodicalIF":4.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12257743/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144636250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}