Frontiers in Microbiology最新文献

{"title":"PGPR and nutrient consortia promoted cotton growth, antioxidant enzymes, and mineral uptake by suppressing sooty mold in arid climate.","authors":"Muhammad Luqman, Maqshoof Ahmad, Abubakar Dar, Azhar Hussain, Usman Zulfiqar, Muhammad Zahid Mumtaz, Adnan Mustafa, Abd El-Zaher M A Mustafa, Mohamed S Elshikh","doi":"10.3389/fmicb.2025.1551465","DOIUrl":"10.3389/fmicb.2025.1551465","url":null,"abstract":"<p><strong>Introduction: </strong>Cotton (<i>Gossypium hirsutum</i> L.) plays a vital role in Pakistan's economy, providing significant employment opportunities and supporting the country's textile industry. However, cotton productivity is severely impacted by pests and diseases, such as black spots caused by sooty mold, posing critical challenges to sustainable agriculture. This study investigates a novel integration of plant growth-promoting rhizobacteria (PGPR) with recommended NPK fertilizers and micronutrients to enhance cotton growth, yield, disease resistance, and post-harvest soil properties.</p><p><strong>Methodology: </strong>A consortium of <i>Bacillus megaterium</i> (ZR19), <i>Paenibacillus polymyxa</i> (IA7), and <i>Bacillus</i> sp. (IA16) were evaluated under six treatments: control (T1), PGPR (T2), recommended NPK (T3), recommended NPK + PGPR (T4), recommended NPK + micronutrients (T5), and recommended NPK + micronutrients + PGPR (T6).</p><p><strong>Results: </strong>The results depicted a significant increase in antioxidant activities of 19% in superoxide dismutase (SOD), 29% peroxidase (POX), 28% peroxidase dismutase (POD), and 14% catalase (CAT) activity under T6 as compared to control. Similarly, growth parameters substantially improved root length (39%), shoot length (19%), and root and shoot biomass by up to 31 and 20%, respectively, under T6. Moreover, the yield attributes like single boll weight and lint percentage were also enhanced by 32 and 13%, respectively, under the integration. In contrast, the PGPR consortium demonstrated considerable biocontrol potential against sooty mold, as disease incidence was reduced by 68% in cotton, the disease index was 75%, and control efficacy reached 75%. The PGPR consortium also substantially improved post-harvest soil biological and chemical properties, including bacterial populations, microbial biomass nitrogen, organic matter, and essential nutrient availability.</p><p><strong>Discussion: </strong>So, these findings witnessed the dual behavior of the <i>Bacillus</i> and <i>Paenibacillus</i> strains with balanced nutrition and can lead us to the development of an effective biopesticide cum biofertilizer for the sustainable production of cotton in arid conditions by combating sooty mold effectively.</p>","PeriodicalId":12466,"journal":{"name":"Frontiers in Microbiology","volume":"16 ","pages":"1551465"},"PeriodicalIF":4.0,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11965598/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143779604","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":"Evaluating the potential of fermented bakery by-products as a replacement for corn gluten feed in cattle diets to suppress methanogenesis and alter rumen fermentation in growing Holstein bulls.","authors":"Xuanxuan Pu, Wanqian Zhang, Fan Yang, Xiumin Zhang, Rong Wang, Qiushuang Li, Xingze Yang, Daliang Cai, Jiabin Huo, Xuezhao Sun, Zhiliang Tan, Bo Lin, Min Wang","doi":"10.3389/fmicb.2025.1485688","DOIUrl":"10.3389/fmicb.2025.1485688","url":null,"abstract":"<p><p>Both corn gluten feed and bakery by-products are important alternative concentrate feedstuffs for ruminants. Bakery by-products, which are rich in ether extract (EE) and starch, have the potential to be utilized as concentrate feedstuffs for ruminants, with a capacity to reduce ruminal methanogenesis. In the study, fermented corn gluten feed (FCG) and fermented bakery by-products (FBP) were mixed with other feedstuffs to formulate FCG and FBP diets, respectively. Twenty growing Holstein bulls, weighing 241 ± 10.5 kg, were randomly assigned to one of two dietary treatments: FCG or FBP diet. The aim was to investigate effects of replacing FCG with FBP feedstuff on nutrient digestibility, ruminal fermentation, ruminal microbiota, and methanogenesis. Results showed that the bulls feeding FBP diet had greater starch intake (<i>p</i> < 0.01) and digestibility (<i>p</i> = 0.04), EE intake (<i>p</i> < 0.01) and digestibility (<i>p =</i> 0.01), molar proportion of ruminal propionate (<i>p</i> < 0.01), while lower crude protein (CP) (<i>p</i> < 0.01) and neutral detergent fiber (NDF) digestibility (<i>p =</i> 0.01), ruminal dissolved methane concentration (<i>p</i> = 0.02), percentage of ruminal acetate (<i>p</i> < 0.01) and butyrate (<i>p</i> < 0.01), and the ratio of acetate to propionate (<i>p</i> < 0.01), in comparison with those feeding FCG diet. Further investigation on the bacterial community indicated that feeding the FBP diet had greater abundance of <i>Succiniclasticum</i> (<i>p</i> = 0.02), <i>Megasphaera</i> (<i>p</i> < 0.01), <i>Lachnospiraceae_unclassified</i> (<i>p</i> < 0.01) and <i>Lachnospira</i> (<i>p</i> < 0.01), while lower abundance of <i>Christensenellaceae_R-7_group</i> (<i>p</i> < 0.01), <i>Ruminococcus</i> (<i>p</i> < 0.01) and <i>NK4A214_group</i> (<i>p</i> = 0.01). The increases in EE and starch intakes after the substitution of FCG by FBP feedstuff alter fermentation rumen pathway from acetate to propionate production through enriching the propionate producers with net hydrogen incorporation, and reduced ruminal methanogenesis.</p>","PeriodicalId":12466,"journal":{"name":"Frontiers in Microbiology","volume":"16 ","pages":"1485688"},"PeriodicalIF":4.0,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11965602/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143779561","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":"Exploring the antibacterial and anti-biofilm properties of Diacerein against methicillin-resistant <i>Staphylococcus aureus</i>.","authors":"Yingying Sun, Yaozhou Wu, Yanbin Chang, Gaoling Sun, Xin Wang, Zhangping Lu, Keke Li, Xiaofang Liang, Qianqian Liu, Wenjie Wang, Lianhua Wei","doi":"10.3389/fmicb.2025.1545902","DOIUrl":"10.3389/fmicb.2025.1545902","url":null,"abstract":"<p><strong>Background: </strong>Methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) poses a significant clinical challenge due to its multidrug resistance. Diacerein (DIA), primarily used to treat degenerative joint diseases, has recently been found to exhibit antibacterial activity, though its specific antibacterial mechanisms remain unclear.</p><p><strong>Methods: </strong>The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of DIA, as well as in - vitro combination susceptibility testing, were determined using the broth microdilution method. Additionally, resistance induction assays, time-growth curve measurements, membrane fluidity, intracellular protein levels, and reactive oxygen species (ROS) were assessed. The inhibition and clearance of MRSA biofilms by DIA were evaluated using the crystal violet staining method, with bacterial morphology and biofilms observed via scanning electron microscopy and confocal laser scanning microscopy. Finally, transcriptome analysis was conducted to identify gene expression changes in MRSA treated with DIA, and RT-qPCR verification was performed.</p><p><strong>Results: </strong>The MIC and MBC of DIA against MRSA were 32 μg/mL and 128 μg/mL, respectively, and synergistic antibacterial effects when combined with ampicillin. DIA increased intracellular ROS levels and membrane fluidity in MRSA, decreased soluble protein synthesis, and altered bacterial morphology. Additionally, DIA significantly inhibited MRSA biofilm formation and disrupted pre - existing biofilms. Transcriptome analysis revealed 1,045 differentially expressed genes between the DIA-treated group and the control group, primarily involving pathways such as the tricarboxylic acid cycle, phosphorylation, ribosome metabolism, and nucleotide metabolism.</p><p><strong>Conclusion: </strong>In summary, DIA has antibacterial and anti-biofilm activities against MRSA and does not easily induce resistance. Its antibacterial mechanisms may involve multiple aspects, including bacterial protein synthesis, energy metabolism.</p>","PeriodicalId":12466,"journal":{"name":"Frontiers in Microbiology","volume":"16 ","pages":"1545902"},"PeriodicalIF":4.0,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11965656/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143779582","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":"Corrigendum: Biostimulation of indigenous microbial community for bioremediation of petroleum refinery sludge.","authors":"Jayeeta Sarkar, Sufia K Kazy, Abhishek Gupta, Avishek Dutta, Balaram Mohapatra, Ajoy Roy, Paramita Bera, Adinpunya Mitra, Pinaki Sar","doi":"10.3389/fmicb.2025.1551928","DOIUrl":"https://doi.org/10.3389/fmicb.2025.1551928","url":null,"abstract":"<p><p>[This corrects the article DOI: 10.3389/fmicb.2016.01407.].</p>","PeriodicalId":12466,"journal":{"name":"Frontiers in Microbiology","volume":"16 ","pages":"1551928"},"PeriodicalIF":4.0,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11965679/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143779600","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":"Longitudinal assessment of the prevalence of <i>Fusobacterium necrophorum</i>, <i>Fusobacterium</i> var<i>ium</i>, and <i>Salmonella enterica</i> in the nasal cavity, ruminal fluid, and feces of finishing beef steers with and without liver abscesses.","authors":"Colten W Dornbach, Paul R Broadway, James E Wells, Kallie D Childress, Aubrey C Thompson-Smith, Landon G Canterbury, Nicole C Burdick Sanchez, Jacque Mathieu, Cory Schwarz, Jenny Laverde Gomez, Marina Tikhonova, T G Nagaraja, Michael L Galyean, Kristin E Hales","doi":"10.3389/fmicb.2025.1565303","DOIUrl":"10.3389/fmicb.2025.1565303","url":null,"abstract":"<p><p>The objective was to longitudinally assess the prevalence of <i>F. necrophorum</i> subsp. <i>necrophorum</i>, <i>F. necrophorum</i> subsp. <i>funduliforme</i>, <i>F.</i> var<i>ium</i>, and <i>Salmonella enterica</i> in the nasal cavity, ruminal fluid, and feces of finishing beef steers with and without LA. Crossbred steers (<i>n</i> = 225; 353 ± 39.6 kg) were transported to a feedlot and fed a high-concentrate diet. Nasal, ruminal fluid, and fecal samples were collected following feedlot arrival (d 5), 1 week after adaptation to a finishing diet (d 35), and the day before harvest (study end). Livers were collected at harvest and examined for LA, and cattle were subsequently assigned into either control or liver abscess groups. Overall LA prevalence was 18.7%. The concentration and prevalence of <i>Salmonella</i> decreased in ruminal fluid and increased in feces with days on feed (<i>p</i> < 0.01). Conversely, ruminal fluid prevalence of <i>F. necrophorum</i> subsp. <i>necrophorum</i> and <i>F.</i> var<i>ium</i> increased with days on feed (<i>p</i> < 0.01). <i>Fusobacterium</i> abundance in ruminal fluid and feces was not indicative of LA development except for <i>F. varium</i> being more abundant in the ruminal fluid of steers with LA (<i>p</i> < 0.01). Abundance of <i>F. necrophorum</i> subsp. <i>necrophorum</i> was greater in abscessed liver tissue than healthy tissue (<i>p</i> = 0.03), although no other differences in bacterial abundance or prevalence were observed in livers. Overall, <i>Fusobacterium</i> and <i>Salmonella</i> prevalence in the nasal cavity, ruminal fluid, and feces were affected by days on feed, but their prevalence and abundance were not indicative of LA occurrence.</p>","PeriodicalId":12466,"journal":{"name":"Frontiers in Microbiology","volume":"16 ","pages":"1565303"},"PeriodicalIF":4.0,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11965686/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143779587","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":"Editorial: Microbial co-cultures: a new era of synthetic biology and metabolic engineering, volume II.","authors":"Durgesh Kumar Jaiswal, Avinash Bapurao Ade, Tarun Belwal, Arthur Prudêncio De Araujo Pereira, Jay Prakash Verma","doi":"10.3389/fmicb.2025.1587450","DOIUrl":"10.3389/fmicb.2025.1587450","url":null,"abstract":"","PeriodicalId":12466,"journal":{"name":"Frontiers in Microbiology","volume":"16 ","pages":"1587450"},"PeriodicalIF":4.0,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11967986/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143779602","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":"Complete genome sequence, metabolic profiling and functional studies reveal <i>Ligilactobacillus salivarius LS-ARS2</i> is a promising biofilm-forming probiotic with significant antioxidant, antibacterial, and antibiofilm potential.","authors":"Sinjini Patra, Biswaranjan Pradhan, Anasuya Roychowdhury","doi":"10.3389/fmicb.2025.1535388","DOIUrl":"10.3389/fmicb.2025.1535388","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;Probiotics restore microbial balance and prevent gut-inflammation. Therefore, finding out novel probiotic strains is a demand. As gut-microbe, benefits of &lt;i&gt;Ligilactobacillus salivarius (LS)&lt;/i&gt; are established. However, strain-specific detailed studies are limited. Here, we illustrate probiotic attributes of novel &lt;i&gt;LS-ARS2&lt;/i&gt; for its potential application as food-supplement and/or therapeutic to improve gut-health.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;Whole genome sequencing (WGS) and phylogenetic analysis confirm the strain as &lt;i&gt;LS&lt;/i&gt;. To establish probiotic properties, acid-bile tolerance, auto-aggregation, cell-surface-hydrophobicity, biofilm-formation, and adhesion-assays are performed. To ensure safety attributes, antibiotic-susceptibility, hemolytic, DNase, trypan-blue, and MTT assays are done. ABTS, DPPH, superoxide, hydroxyl free radical scavenging assays are used to determine anti-oxidant potential. Antibacterial assays, including co-culture assay with pathogen and pathogenic biofilm-inhibition assays, are performed to explore antibacterial efficacy. To characterize metabolic-profile of &lt;i&gt;LS-ARS2&lt;/i&gt;-derived cell-free-supernatant (CFS), HRMS analysis are carried out. Consequently, WGS-analyses predict potential molecular associations related to functional outcomes.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;We find &lt;i&gt;LS-ARS2&lt;/i&gt; a remarkable fast-growing strain that shows acid and bile tolerance (&gt;60% survival rate), indicating promising gut-sustainability. High auto-aggregation capacity (&gt;80%), robust cell-surface hydrophobicity (&gt;85%), and adhesion efficacy to Caco-2 cells illustrate significant potential of &lt;i&gt;LS-ARS2&lt;/i&gt; for gut colonization. Fascinatingly, &lt;i&gt;LS-ARS2&lt;/i&gt; is able to form biofilm within 24 h (&lt;i&gt;p&lt;/i&gt; &lt; 0.0001), rare among &lt;i&gt;LS&lt;/i&gt; strains, indicating the potential of the strain for efficient stay in the gut. The strain ensures safety attributes. &lt;i&gt;LS-ARS2&lt;/i&gt;-WGS analysis recognizes probiotic-specific determinants, predicts genomic stability, identifies orthologous-clusters for diverse functions, and predicts metabolites and bacteriocins. HRMS-studies with &lt;i&gt;LS-ARS2-&lt;/i&gt;CFS further validate the presence of diverse beneficial metabolites with antimicrobial and immunomodulatory potential. &lt;i&gt;LS-ARS2&lt;/i&gt; shows significant antioxidant properties in ABTS (&gt;60%), DPPH (&gt;10 U/mL), superoxide (&gt;70%), and hydroxyl free radical scavenging assays (&gt;70%). Further, &lt;i&gt;LS-ARS2&lt;/i&gt; shows antimicrobial activities against Gram-positive Methicillin-resistant &lt;i&gt;Staphylococcus aureus (MRSA)&lt;/i&gt; and Gram-negative multidrug-resistant clinical strains enterotoxigenic &lt;i&gt;Escherichia coli, Vibrio cholerae,&lt;/i&gt; and &lt;i&gt;Shigella flexneri&lt;/i&gt;. Anti-&lt;i&gt;Salmonella&lt;/i&gt; effect of &lt;i&gt;LS-ARS2&lt;/i&gt; is prominent (&lt;i&gt;p&lt;/i&gt; &lt; 0.0001). Most interestingly, &lt;i&gt;LS-ARS2&lt;/i&gt;-CFS inhibits &lt;i&gt;MRSA&lt;/i&gt;-biofilm (&lt;i&gt;p&lt;/i&gt; &lt; 0.0001), again rare among &lt;i&gt;LS&lt;/i&gt; strains.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusion: &lt;/strong&gt;&lt;i&gt;LS-ARS2&lt;/i&gt; is a novel, fast-grow","PeriodicalId":12466,"journal":{"name":"Frontiers in Microbiology","volume":"16 ","pages":"1535388"},"PeriodicalIF":4.0,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11965632/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143779597","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":"Enhancing bloodstream infection diagnostics: a novel filtration and targeted next-generation sequencing approach for precise pathogen identification.","authors":"Ting-Syuan Lin, ZiHao Zhu, XiaoHong Lin, Hsi-Yuan Huang, Li-Ping Li, Jing Li, Jie Ni, PeiZhi Li, LanChun Chen, WeiXin Tang, HuiXin Liu, XiaoLong Se, MingFei Xie, Canling Long, Chih-Min Chiu, Szu-Han Fang, JiaMing Zhao, Yang-Chi-Dung Lin, XueTao Yu, Hsien-Da Huang","doi":"10.3389/fmicb.2025.1538265","DOIUrl":"10.3389/fmicb.2025.1538265","url":null,"abstract":"<p><p>Bloodstream infections (BSIs) pose a significant diagnostic challenge, largely due to the limitations of traditional methods such as blood cultures. These methods often yield low positive rates, have lengthy processing times that delay treatment, and are limited in detecting only a narrow range of pathogens. Such delays and inaccuracies can critically impede timely clinical interventions, potentially compromising patient outcomes. Next-generation sequencing (NGS) is a powerful tool for rapid, precise pathogen identification. While metagenomic NGS (mNGS) offers broad pathogen coverage, it is often costly and complex. Targeted NGS (tNGS), however, focuses on key regions of clinically relevant pathogens, reducing costs and simplifying workflows while maintaining high sensitivity, making it more practical for routine diagnostics. In this study, we introduce a novel approach combining a human cell-specific filtration membrane with a multiplex tNGS panel to overcome these challenges. The filtration membrane, designed with surface charge properties to be electrostatically attractive to leukocytes for the selective capture of specific cells, demonstrated high efficiency in removing host cells and nucleic acids, achieving over a 98% reduction in host DNA and thereby minimizing background interference in pathogen detection. Additionally, we developed an effective multiplex tNGS panel targeting over 330 clinically relevant pathogens and verified its consistency with mNGS and blood culture results, demonstrating a significant improvement in detection sensitivity. By integrating these two methods, we achieved a synergistic enhancement in diagnostic capability, boosting pathogen reads by 6- to 8-fold, which enabled reliable identification even in cases of low-abundance pathogens. This approach provides faster, more accurate, and more sensitive detection of BSIs, enabling earlier identification of infections. This facilitates timely and targeted treatment, ultimately improving patient outcomes in critical care settings. Given the unique properties of the filtration membrane and the strengths of the tNGS panel, this approach shows promising applications in prenatal and genetic health support, as well as in advancing early cancer screening strategies.</p>","PeriodicalId":12466,"journal":{"name":"Frontiers in Microbiology","volume":"16 ","pages":"1538265"},"PeriodicalIF":4.0,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11965694/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143779557","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":"Study on the invitro synergistic susceptibility and biofilm inhibition mechanism of ceftazidime-avibactam combined with aztreonam against carbapenem-resistant <i>Klebsiella pneumoniae</i>.","authors":"Guangfen Wang, Hui Zhang, Qiaoping Wu, Jianqiang Xu, Xuedan Qiu, Jinyuan Chen, Fujie Cui, Jian Zhou, Qingcao Li","doi":"10.3389/fmicb.2025.1542029","DOIUrl":"10.3389/fmicb.2025.1542029","url":null,"abstract":"<p><strong>Objective: </strong>This study aims to investigate the synergistic effects and biofilm inhibition mechanisms of ceftazidime-avibactam (CZA) combined with aztreonam (ATM) against carbapenem-resistant <i>Klebsiella pneumoni</i>a (CRKP) commonly found in the local clinical setting, providing new insights for clinical anti-infective strategies.</p><p><strong>Methods: </strong>We selected a total of 150 non-duplicate clinical isolates of CRKP from multiple hospitals in Ningbo. Common carbapenemase genes were detected using PCR. Broth microdilution and time-kill assays were used to evaluate the <i>in vitro</i> synergistic effects of CZA and ATM, both individually and in combination, on CRKP isolates with different enzyme types, and the fractional inhibitory concentration index (FICI) was calculated. The crystal violet staining method and bacterial cell permeability assay were employed to assess the impact of CZA, ATM, and their combination on the cell structure and biofilm formation capacity of CRKP. Real-time quantitative PCR (qRT-PCR) was used to measure the expression levels of biofilm-related genes (<i>Luxs</i>, <i>mrkA</i>, <i>wbbM</i>, <i>pgaA</i>, and <i>wzm</i>) in CRKP under treatment with CZA, ATM, or their combination.</p><p><strong>Results: </strong>The comparison of synergistic indices for different enzyme-type CRKP strains with CZA and ATM combination therapy showed a statistically significant difference (<i>p</i> < 0.01). The time-kill assay indicated that the time-kill curves for strains carrying <i>blaKPC-2</i> and <i>blaNDM-1</i> resistance genes were similar between the monotherapy and combination therapy groups, while the CZA + ATM combination therapy group showed a significant decrease in bacterial concentration after 4-8 h of cultivation compared to the CZA and ATM monotherapy groups. The crystal violet staining and bacterial cell permeability assays demonstrated that the CZA + ATM combination significantly reduced biofilm formation and increased cellular structure disruption in CRKP. The qRT-PCR results showed that CZA combined with ATM notably decreased the expression levels of biofilm-related genes <i>Luxs</i>, <i>mrkA</i>, <i>wbbM</i>, <i>pgaA</i>, and <i>wzm</i> in CRKP.</p><p><strong>Conclusion: </strong>The combination of ATM and CZA shows a strong synergistic antibacterial effect against CRKP strains with various enzyme types, with particularly notable synergy in strains carrying the <i>blaKPC-2</i> resistance gene. Additionally, this combination significantly disrupts the cellular structure of CRKP and inhibits biofilm formation.</p>","PeriodicalId":12466,"journal":{"name":"Frontiers in Microbiology","volume":"16 ","pages":"1542029"},"PeriodicalIF":4.0,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11965359/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143779606","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":"<i>Mycoplasma penetrans</i> urethritis in men. A case-control study.","authors":"Luis Piñeiro, Pedro Idigoras, Ayla Manzanal, Iñigo Ansa, Diego Vicente","doi":"10.3389/fmicb.2025.1565685","DOIUrl":"10.3389/fmicb.2025.1565685","url":null,"abstract":"<p><strong>Introduction: </strong>A microbiological diagnosis is not reached in many urethritis cases, the proportion varying with the diagnostic methods and targets available. <i>Mycoplasma penetrans</i> is an emerging pathogen, recently described as a possible aetiological agent in urethritis, especially in men who have sex with men (MSM) and persons living with HIV.</p><p><strong>Methods: </strong>Between June 2021 and June 2024, urethral samples from men were analysed for the presence of <i>M. penetrans</i> using an in-house real-time PCR, and for other sexually transmitted infections with standard techniques (gram stain, culture, PCR, and serology). Three groups were studied, one comprising 55 consecutive cases of urethritis in which the infectious aetiology had not previously been identified, and two randomly obtained control groups: 102 patients with microbiologically-identified urethritis, and 91 patients with no manifestations of urethritis and no pathogen detected.</p><p><strong>Results and discussion: </strong><i>M. penetrans</i> DNA was detected in 7/55 (12.7%) of the idiopathic urethritis cases, but not in any of the controls (<i>p</i> < 0.001). None of the <i>M. penetrans</i>-positive patients had HIV infection and six were MSM. The results from this study indicate an association between infection by <i>M. penetrans</i> and urethritis in men. Therefore, the use of techniques for detecting <i>M. penetrans</i> could help bridge the diagnostic gap in idiopathic urethritis.</p>","PeriodicalId":12466,"journal":{"name":"Frontiers in Microbiology","volume":"16 ","pages":"1565685"},"PeriodicalIF":4.0,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11961646/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143771663","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}