BMC Microbiology最新文献

{"title":"Molecular and phenotypic profiles of carbapenem- and third-generation cephalosporin-resistant Klebsiella pneumoniae isolates from the fecal microbiota of pediatric patients with COVID-19.","authors":"Mahmoud A F Khalil, Mahmoud R M El-Ansary, Sara I AboElnour, Shaimaa Madkour, Walid F Elkhatib, Eman E Mahmoud, Eman Fares, Fatma A Ahmed","doi":"10.1186/s12866-026-05426-5","DOIUrl":"10.1186/s12866-026-05426-5","url":null,"abstract":"<p><strong>Background: </strong>Gut colonization with multidrug-resistant (MDR) Klebsiella pneumoniae is commonly associated with an increased risk of extraintestinal infections among hospitalized patients. Extensive antibiotic exposure during the COVID-19 pandemic, is a critical contributing factor for the emergence of resistant strains. This investigation sought to elucidate the phenotypic and molecular resistance traits of carbapenem-resistant K. pneumoniae (CRKP) and extended-spectrum β-lactamase-producing K. pneumoniae (ESBL-KP) colonizing the gut of pediatric patients with confirmed COVID-19.</p><p><strong>Methods: </strong>A cross-sectional study was conducted from October 2020 to March 2022 at a tertiary pediatric hospital in Fayoum, Egypt. Fecal samples were collected from hospitalized pediatric COVID-19 patients. K. pneumoniae isolates were identified using standard microbiological methods. Antimicrobial susceptibility testing was carried out in accordance with the CLSI guidelines. ESBL and carbapenemase production were assessed phenotypically, while resistance genes were detected by multiplex and uniplex PCR. Microtiter plate method was used to assess biofilm formation.</p><p><strong>Results: </strong>K. pneumoniae was detected in 36 of 71 patients (50.7%) using antibiotic-supplemented selective culture. The isolated strains were exclusively resistant, including 22 CRKP and 14 ESBL-KP. Colistin susceptibility was maintained in all isolates. CRKP strains showed significantly increased rate of resistance to fluoroquinolones and amikacin compared with ESBL-KP. Bla_NDM gene (54.5%) and bla_KPC (45.5%) were detected among CRKP isolates. ESBL-associated genes bla_CTX-M, bla_TEM, and bla_SHV were prevalent in both groups. Biofilm formation was common and comparable between CRKP and ESBL-KP isolates.</p><p><strong>Conclusion: </strong>A high prevalence of fecal carriage of MDR K. pneumoniae, driven by carbapenemase-producing strains, was observed among hospitalized pediatric COVID-19 patients. These outcomes highlight the necessity for routine colonization surveillance, optimized antimicrobial stewardship, and strengthened infection control strategies in pediatric settings.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"26 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2026-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13393905/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148577224","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":"Repurposing amlodipine, fluoxetine, and escitalopram as non-antibiotic adjuvants: in vitro enhancement of ciprofloxacin and fluconazole activity against multidrug-resistant bacterial and candida clinical isolates.","authors":"Mohammed A Alkhawlani, Wafa M Al-Madhagi, Mahmoud Mahyoob Alburyhi, Ali Gamal Al-Kaf, Maged Al-Najar","doi":"10.1186/s12866-026-05443-4","DOIUrl":"10.1186/s12866-026-05443-4","url":null,"abstract":"<p><strong>Introduction: </strong>Multidrug-resistant (MDR) Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans threaten treatment success, particularly in resource-limited settings. Repurposing licensed, inexpensive non-antibiotic drugs may provide a strategy for enhancing the activity of established antimicrobial agents.</p><p><strong>Methods: </strong>Clinical isolates from Sana'a, Yemen, and American Type Culture Collection (ATCC) reference strains were tested in vitro with amlodipine, fluoxetine, and escitalopram, individually and in dual or triple combinations with ciprofloxacin or fluconazole. Antimicrobial activity was evaluated using agar-well diffusion, broth microdilution minimum inhibitory concentration (MIC), minimum bactericidal or fungicidal concentration (MBC/MFC), and checkerboard fractional inhibitory concentration index (FICI) assays. Molecular docking with AutoDock Vina was used to explore plausible interactions with MurB (PDB 1HSK), LasR (PDB 3IX3), and CYP51 (PDB 5V5Z). Normal mode analysis (NMA) with iMODS was performed for selected fluoxetine-LasR and fluoxetine-MurB complexes as a preliminary structural-dynamics assessment.</p><p><strong>Results: </strong>Fluoxetine produced inhibition zones of at least 27 mm across the tested organisms. Amlodipine produced larger zones against S. aureus and C. albicans than against P. aeruginosa, whereas escitalopram produced smaller zones overall. Checkerboard testing identified synergy (FICI ≤ 0.50) for selected combinations. Selected triple combinations reduced MIC values by 4- to 64-fold. The largest diffusion readouts were observed with ciprofloxacin + fluoxetine + amlodipine against S. aureus (101 mm), ciprofloxacin + fluoxetine + escitalopram against P. aeruginosa (88.5 mm), and ciprofloxacin + amlodipine + fluconazole against C. albicans (138.5 mm). Docking scores and NMA outputs provided hypothesis-generating structural context for the experimental findings.</p><p><strong>Conclusions: </strong>Antimicrobial enhancement was combination- and organism-dependent. Selected combinations showed checkerboard-defined synergy, whereas diffusion assays were interpreted as screening outcomes only. Docking and NMA findings were supportive and hypothesis-generating but did not establish target engagement or mechanism.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"26 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2026-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13679258/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149219884","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":"Transcriptomic insights on differential gene regulations in viable but non-culturable (VBNC) bacteria under chlorine and UV disinfection.","authors":"Mandy Lok Yi Tang, Eunice Yuen Man Chung, Erin Yee Nam Yu, Stanley Chun Kwan Lau","doi":"10.1186/s12866-026-05441-6","DOIUrl":"10.1186/s12866-026-05441-6","url":null,"abstract":"<p><strong>Background: </strong>Bacteria entering viable but non-culturable (VBNC) state as a stress response to disinfection is one of the major challenges in sewage treatment, as these bacteria evade culture-based detection methods while retaining metabolic activities, pathogenicity, and the possibility to resuscitate, raising concerns for the public health risks of effluent discharge. The formation of VBNC cells and their gene regulations among different intrinsic and extrinsic conditions (e.g. stress factors, bacterial species and environmental conditions) are yet to be investigated. To facilitate the understanding of bacterial stress tolerance and adaptation under disinfection, we conducted a multifaceted investigation into the VBNC formation and differential gene expression of two commonly used fecal indicator bacteria (Escherichia coli and Enterococcus faecium) under the effect of different disinfectants (chlorine and UV-C), strains (sewage-isolated and ATCC reference), and surrounding media (effluent and PBS).</p><p><strong>Results: </strong>The formation of VBNC cells was observed after disinfection across all experimental conditions. Notably, the proportion of VBNC cells in effluents after chlorine treatment reached over 90% of the total population. Differentially expressed genes (DEGs) were observed in the transcriptomes of treated cells (containing viable cells without culturable cells) compared to the untreated cells. UV-C treated bacteria primarily upregulated carbohydrate metabolism, DNA repairing, and toxin-antitoxin systems, whereas chlorine-treated bacteria upregulated exopolysaccharide production, phosphotransferase system, and secondary carbon metabolism while suppressing central carbon and other energy metabolism. Both chlorine- and UV-C treated cells exhibited downregulation of DNA replication, transcription, and the biogenesis of RNA, ribosome and chromosome. However, most DEGs related to bacterial secretion system were exclusively upregulated in E. coli; only Type IV pili components were upregulated in E. faecium. Tetracycline and vancomycin resistance genes were particularly upregulated in the E. faecium strains isolated from sewage but not the laboratory reference strains, indicating the strain-to-strain variations in metabolic activities. Besides, more DEGs were identified in cells suspended in effluents than in PBS under chlorination, showing different extent of transcriptomic shifts between media.</p><p><strong>Conclusions: </strong>This study revealed distinct responses and adaptive mechanisms of bacteria against chlorine and UV-C disinfection. The presence of VBNC populations at extreme dosages highlighted their high tolerance against disinfectants. Moreover, the alterations in gene expression profiles suggested some gene regulations associated with the non-reproductive and energy conserving traits in stressed cells, and reflected the potential risks of bacterial pathogenicity in disinfected effluents.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"26 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2026-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13681853/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149223384","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":"Genomic, virulent and phenotypic characterization of a cerebrospinal fluid-derived ST86-KL2 hypervirulent Klebsiella pneumoniae isolate from a patient with meningitis and diabetes mellitus.","authors":"Xiyun Lai, Xinyu Zhu, Jie Yan, Tingjian Zou, Mengyuan Chen, Heng Chen, Xiaofang Tang, Qiang Wang","doi":"10.1186/s12866-026-05433-6","DOIUrl":"10.1186/s12866-026-05433-6","url":null,"abstract":"<p><strong>Background: </strong>Hypervirulent Klebsiella pneumoniae (hvKP) is an important cause of invasive community-acquired infection, particularly in individuals with diabetes mellitus. However, cerebrospinal fluid (CSF)-derived hvKP isolates, especially those belonging to the ST86-KL2 lineage, remain poorly characterized at the integrated clinical, genomic, and phenotypic levels.</p><p><strong>Methods: </strong>A K. pneumoniae isolate, designated BP9811, was recovered from the CSF of a patient with meningitis and diabetes mellitus and identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and 16 S rRNA sequencing. Antimicrobial susceptibility testing and whole-genome sequencing were performed to define its resistance, virulence, sequence type (ST), capsular type, and plasmid content. Virulence was evaluated using the Galleria mellonella infection model. In addition, interaction with human cerebral microvascular endothelial cells was preliminarily assessed using adhesion, gentamicin protection, and transmission electron microscopy assays, together with measurement of relative ompA transcription by reverse transcription-quantitative polymerase chain reaction. Comparative phylogenetic analyses were performed using publicly available CSF-derived and KL2 K. pneumoniae genomes.</p><p><strong>Results: </strong>BP9811 was identified as a hypermucoviscous ST86-KL2 hvKP isolate that remained susceptible to all tested antimicrobial agents. Whole-genome sequencing revealed an IncHI1B virulence plasmid carrying canonical hvKP-associated determinants, including rmpA/rmpA2, peg-344, iucABCD, and iroBCD. In the Galleria mellonella model, BP9811 showed high virulence comparable to that of the hypervirulent reference strain NTUH-2044. In HCMEC/D3 cells, BP9811 exhibited increased adhesion and intracellular recovery under the tested conditions, and transmission electron microscopy confirmed bacterial internalization. BP9811 also showed higher ompA transcript levels than the control strain. Phylogenetic analysis indicated that BP9811 was genetically distinct from currently available CSF-derived isolates and occupied a related branch within the KL2 population.</p><p><strong>Conclusions: </strong>This study provides an integrated clinical, genomic, and phenotypic characterization of BP9811, a CSF-derived ST86-KL2 hvKP isolate recovered from a patient with meningitis and diabetes mellitus. BP9811 carried a canonical hvKP virulence plasmid, displayed marked virulence-associated phenotypes, and showed enhanced interaction with human cerebral microvascular endothelial cells in vitro under the tested conditions. These findings expand the limited isolate-level evidence on central nervous system-associated hvKP and provide a basis for future comparative and mechanistic studies.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"26 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2026-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13560199/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148928959","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":"Long-term epidemiology of bacterial pathogens and antimicrobial resistance in a secondary hospital in China: a 12-year retrospective study.","authors":"Li Yingxing, Guo Lina, Li Fangyuan, Li Jie, Guo Wenting, Zhao Hongmei","doi":"10.1186/s12866-026-05445-2","DOIUrl":"10.1186/s12866-026-05445-2","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;Antimicrobial resistance (AMR) is a growing global health threat. However, long-term epidemiological data from secondary hospitals-a critical component of the healthcare system-remain limited, particularly in China, where national surveillance is largely based on data from tertiary hospitals. Understanding the local epidemiology in these settings is vital for developing effective regional control strategies and guiding empirical antibiotic therapy.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;We conducted a retrospective analysis of 2,661 clinical bacterial isolates collected from a secondary hospital in Shandong Province, China, between 2014 and 2025. Pathogen distribution was analyzed across patient sex, age groups, specimen types, and temporal trends. Antimicrobial susceptibility data from 2017 to 2025 were used to assess resistance profiles of major pathogens. Key resistant organisms, including methicillin-resistant Staphylococcus aureus (MRSA), extended-spectrum β-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae, carbapenem-resistant Enterobacterales (CRE), carbapenem-resistant Acinetobacter baumannii (CRAB), and carbapenem-resistant Pseudomonas aeruginosa (CRPA), were further evaluated.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;Gram-negative bacteria predominated (83.1%), with E. coli (30.9%) and K. pneumoniae (25.6%) as the most common pathogens. Distinct ecological niche patterns were observed: E. coli was overrepresented in urinary and wound samples and in female patients, whereas K. pneumoniae, P. aeruginosa, and A. baumannii were associated with respiratory samples and elderly male patients. Over the 12-year period, the detection rate of K. pneumoniae increased gradually, while that of S. aureus declined. Marked interspecies differences in antimicrobial resistance were evident, with A. baumannii exhibiting high resistance rates (&gt; 60%) to most tested antibiotics, and E. coli showing substantial resistance to commonly used agents, including ampicillin, fluoroquinolones, and gentamicin (&gt; 50%). Among the selected priority resistant pathogens, CRAB showed the highest detection rate (67.1%), while CRE demonstrated a gradual upward trend. ESBL-producing E. coli was the major contributor to AMR burden across most specimen types, particularly in urinary tract infections, whereas ESBL-producing K. pneumoniae and CRAB predominated in respiratory samples, highlighting niche-specific resistance patterns.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusion: &lt;/strong&gt;Our findings reveal ecological and temporal patterns of bacterial distribution and antimicrobial resistance in a secondary hospital setting. By integrating long-term surveillance with stratified analyses across patient populations and specimen types, this study provides context-specific epidemiological evidence that may inform empirical antimicrobial therapy and antimicrobial stewardship, strengthen local AMR surveillance in county-level secondary hospitals, and complement national ","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"26 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2026-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13540919/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148886364","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":"Agricultural traits, silage quality and bacterial community structure changes of different sorghum varieties in cold regions of Hulunbuir.","authors":"Zhaorui Han, Xun Chen, Sen Zong, Chao Jiang, Wenkai Zhu, Xiwen Su, Weiqiang Song, Xingzhao Zhou, Yanyan Liu, Wenge Li, Yulin Li, Meiling Hou, Yanzi Xiao","doi":"10.1186/s12866-026-05437-2","DOIUrl":"10.1186/s12866-026-05437-2","url":null,"abstract":"<p><p>Selecting high-quality forage varieties is essential for stabilizing regional forage supply and enhancing feed conversion efficiency. This study evaluated agronomic traits, nutritive value, and fermentation characteristics of five forage sorghum varieties (FS3501, QCDS, F10, 3701, and DJ) from the cold Hulunbuir region of China. All cultivars were harvested at the milk-ripe stage to measure plant height and dry matter (DM) yield. Forage was chopped, vacuum-sealed, and ensiled at 25 °C for 60 days. Post-fermentation, nutritional composition and fermentation parameters were analyzed. Additionally, 16 S rRNA gene sequencing with KEGG pathway analysis assessed bacterial community structure and metabolic function dynamics.Results showed that the 3701 (SB4) variety had superior production performance, with the highest (p < 0.05) plant height (2.54 m vs. 1.54-1.93 m) and DM yield (1567.65 kg/hm² vs. 800.40-1067.20 kg/hm²). SB4 also exhibited optimal silage fermentation, featuring the lowest pH (3.58 vs. 3.63-3.74), highest crude protein (6.79 vs. 3.44-6.43 g/kg DM), and lactic acid content (33.00 vs. 16.80-25.52 g/kg DM). Furthermore, SB4 significantly reduced neutral detergent fiber (NDF) and acid detergent fiber (ADF) levels. Microbial analysis revealed decreased α-diversity and a shift from Proteobacteria to Firmicutes, with SB4 silage dominated by Lactobacillus. KEGG functional prediction indicated that carbohydrate metabolism was the predominant metabolic pathway. These findings highlight SB4 as a superior forage variety suitable for cultivation and silage production in high-latitude cold regions like Hulunbuir.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":"26 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2026-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13673768/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149191196","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":"Ec_Ou_ZC1, a new Tunavirus, reveals Cor superinfection exclusion and differential Avs susceptibility across Drexlerviridae subfamilies.","authors":"Quanrui Zhang, Yingying Liu, Jiaoxia Qin, Jixia Wei, Fan Yang, Tao Zhang, Qunxin She, Chen Zhang, Min Wu","doi":"10.1186/s12866-026-05347-3","DOIUrl":"10.1186/s12866-026-05347-3","url":null,"abstract":"<p><p>The global rise of antibiotic resistance has rekindled interest in bacteriophages (phages) as alternative therapeutics. Here, we isolated and characterized a novel Escherichia coli phage, Ec_Ou_ZC1, from the family Drexlerviridae, genus Tunavirus, sharing 94.72% genomic identity with Escherichia phage phiD2-2. Ec_Ou_ZC1 encodes an orphan methyltransferase and a Cor superinfection exclusion (SIE) protein. Heterologous expression of Cor blocked all tested FhuA-dependent Drexlerviridae phages (Ec_Ou_ZC1, T1, Bas03, Bas12, Bas13) but not T4 or T7, confirming family-specific SIE through FhuA receptor inactivation. Plaque assays against four antiviral STAND (Avs) systems revealed differential susceptibility within Drexlerviridae: Bas03 (Braunvirinae) was sensitive to SeAvs3, while Ec_Ou_ZC1, Bas05, Bas12, Bas13, and T1 (Tempevirinae and Tunavirinae) resisted all four systems, suggesting that Avs resistance depends on specific genomic features. Species-level phylogenetic analyses using concatenated single-copy orthologs robustly resolved evolutionary relationships within Tunavirus, separating Escherichia- and Shigella-infecting phages and providing a framework for predicting host range of new isolates.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":" ","pages":""},"PeriodicalIF":5.4,"publicationDate":"2026-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13673623/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148547508","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":"Root-zone waterproof cultivation advanced coloring by accumulation anthocyanins and modulated epiphytic bacteria rebuilding in Marselan grape.","authors":"Xiaoshu Jing, Yuxia Sun, Ling Su, Yang Yang, Dongyue Yang, Xueqiang Guan","doi":"10.1186/s12866-026-05418-5","DOIUrl":"10.1186/s12866-026-05418-5","url":null,"abstract":"<p><strong>Background: </strong>In Shandong Peninsula, the hygrothermal and rainy climate leads to unstable wine color and insufficient aroma of wine grapes. Plant cultivation patterns play a crucial role with various advantages. Root-zone waterproof cultivation is a cultivation technique by restricting the external water entering the root-zone during the rainy season. This study aims to investigate the berry quality, rhizospheric and epiphytic bacterial communities, the anthocyanins contents and the correlation analysis between anthocyanins and bacterial community under the root-zone waterproof treatment.</p><p><strong>Results: </strong>Compared to normal conditions, the root zone waterproof cultivation advanced coloring at early veraison and accumulated more total soluble solids at maturity stage. LC-MS data showed that the root zone waterproof cultivation reduced the procyanidin contents and accumulated more anthocyanin 3-O-glucosides/galactosides at early veraison. There were significant differences in the diversity and relative abundance of epiphytic microorganisms between the normal conditions and the root zone waterproof treatment at maturity stage. Moreover, correlation network between anthocyanin profiles and microorganisms showed that petunidin-3-O-(6''-O-caffeoyl)-galactoside, petunidin-3-O-(6''-O-malonyl)galactoside, malvidin-3-O-(6''-O-acetyl)galactoside and delphinidin at early veraison were more closely related to the the bacterial community at maturity stage. Thus the changed specific anthocyanins modulated the structure of grape epiphytic bacterial communities. At the same time, the berries at S3 stage exhibated higher total antioxidant capacity to alleviate plant stress during the rainy season.</p><p><strong>Conclusions: </strong>The root zone waterproof cultivation pattern emerges as a potential alternative choice for the sustainable management of wine grapes in Shandong Peninsula.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":" ","pages":""},"PeriodicalIF":5.4,"publicationDate":"2026-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13673674/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148547645","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":"Metallo-β-lactamase mediated resistance and Class 1 integron in carbapenem-resistant Enterobacterales isolates from the clinical specimens of Nepal.","authors":"Manisha Shrestha, Suchitra Thapa, Basudha Shrestha, Dev Raj Joshi, Yojana Pokhrel, Jivan Shakya, Reshma Tuladhar","doi":"10.1186/s12866-026-05439-0","DOIUrl":"https://doi.org/10.1186/s12866-026-05439-0","url":null,"abstract":"<p><strong>Background: </strong>Carbapenem-resistant Enterobacterales (CRE) pose an escalating public health threat due to their limited therapeutic options and their potential for rapid dissemination in healthcare settings. Mobile genetic elements (MGEs), such as integrons, facilitate the acquisition and dissemination of antimicrobial resistance genes, contributing to multidrug resistance. This study aimed to detect metallo-β-lactamase (MBL) encoding genes, bla_NDM-1, bla_VIM, and bla_IMP, as well as class 1 integron gene (intI1) among clinical CRE isolates in a tertiary care hospital in Nepal.</p><p><strong>Methods: </strong>A six-month observational cross-sectional study was conducted in a tertiary care hospital in Nepal. A total of 3,255 clinical specimens were processed to isolate Enterobacterales species and to assess their antibiotic susceptibility by Kirby-Bauer disc diffusion. Carbapenemase and MBL production were phenotypically confirmed by the modified carbapenem inactivation method (mCIM) in combination with the EDTA-modified carbapenem inactivation method (eCIM). MBL encoding genes bla_NDM-1, bla_VIM, and bla_IMP and class 1 integron (intI1) were detected by polymerase chain reaction.</p><p><strong>Results: </strong>Among 464 Enterobacterales isolates, 58.6% were multidrug-resistant, and 13.6% were carbapenem-resistant. Phenotypic detection confirmed MBL production in 84.1% of CRE isolates. The bla_NDM-1 and bla_VIM genes were detected in 57.1% and 31.7% CRE isolates, respectively, while bla_IMP was not detected in any of the isolates. Notably, the class 1 integron gene was present in 98.4% of CRE isolates, indicating a high potential for horizontal gene transfer.</p><p><strong>Conclusions: </strong>The high prevalence of MBL genes and class 1 integrons among CRE isolates highlights a substantial risk of carbapenem resistance spreading in healthcare settings in Nepal. These findings emphasize the urgent need for prompt detection, enhanced infection control and antimicrobial stewardship to curb the spread of highly resistant Enterobacterales.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":" ","pages":""},"PeriodicalIF":5.4,"publicationDate":"2026-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148547543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improving growth and lipid accumulation in a novel oleaginous fungus Fusarium solani as a promising feedstock for biodiesel: optimization of growth medium and fatty acid characterization.","authors":"Sedky H A Hassan, Mustafa A Fawzy, Hana Sonbol, Albandary N Alsaloom, Mostafa Koutb, Amany G Ibrahim","doi":"10.1186/s12866-026-05396-8","DOIUrl":"10.1186/s12866-026-05396-8","url":null,"abstract":"<p><strong>Background: </strong>The production of microbial lipids from oleaginous fungi is a promising method to support sustainable biofuels, but maximizing biomass and lipid accumulation requires carefully optimizing growth conditions using effective statistical approaches. The aim of this study was to enhance the biomass and lipid accumulation of a newly indigenous strain of the oleaginous fungus Fusarium solani OQ275245 by assessing the correlation between experimental results and independent design variables. The optimization process used a Box-Behnken experimental design with a response surface methodology, selecting starch, peptone, and inoculum size as independent parameters. The impacts of the parameters on the dependent responses (biomass yield, lipid yield, and lipid content) were investigated using response surfaces and contour plots, and the data was analyzed using ANOVA.</p><p><strong>Results: </strong>The optimal culture conditions were starch, peptone, and inoculum size at levels of 38.43 g/L, 0.53 g/L, and 1.0%, respectively. After validation of quadratic models, it was found that the optimized medium increased biomass yield by 1.06-fold, from 20.80 ± 1.90 g/L to 22.04 ± 2.51 g/L; lipid yield increased by 4.03-fold, from 1.31 ± 0.38 g/L to 5.28 ± 0.55 g/L; and the lipid content increased 3.81-fold, from 6.29 ± 1.36% to 23.96 ± 0.99% compared to the non-optimized medium. Hence, the use of RSM contributed to determining the concentrations of the studied variables to enhance biomass and lipid production in the fungal strain. Furthermore, fungal lipids analyzed by GC/MS were found to contain a high amount of long-chain saturated fatty acids, including myristic acid, palmitic acid, and stearic acid. This indicated that the Fusarium strain had a good fatty acid composition that can be effectively applied for production of biodiesel. Ultimately, we evaluated the characteristics of biodiesel generated by the F. solani strain, and the results met established criteria.</p><p><strong>Conclusions: </strong>These results suggest that Fusarium solani OQ275245 represents a sustainable and promising resource for the production of microbial lipids suitable for biofuel applications, and that the use of surface response methodology is an effective approach for improving the production of biomass and high-quality lipids.</p>","PeriodicalId":9233,"journal":{"name":"BMC Microbiology","volume":" ","pages":""},"PeriodicalIF":5.4,"publicationDate":"2026-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13602762/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148547518","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}