International Journal of Microbiology最新文献

{"title":"Cyanobacteria-Pesticide Interactions and Their Implications for Sustainable Rice Agroecosystems.","authors":"Sadhana Yadav, Rupanshee Srivastava, Nidhi Singh, Tripti Kanda, Ekta Verma, Piyush Choudhary, Shivam Yadav, Neelam Atri","doi":"10.1155/ijm/7265036","DOIUrl":"https://doi.org/10.1155/ijm/7265036","url":null,"abstract":"<p><p>Modern agricultural practices rely heavily on fertilizers and pesticides to boost crop yields, essential for feeding the growing global population. However, their extensive use poses significant environmental risks. Chemical-based fertilizers and pesticides persist in ecosystems, potentially harming ecological stability. Wetland rice farming utilizing nitrogen-fixing cyanobacteria has emerged as an ecofriendly alternative, drawing attention due to its capacity to mitigate pesticide-related issues. Cyanobacteria, capable of fixing atmospheric nitrogen, thrive in low-nitrogen conditions and can aid plant growth. Some species can also biodegrade pesticides, offering a means to clean up contaminated environments. Researchers are exploring ways to leverage cyanobacteria's nitrogen fixation and biodegradation abilities for ecofriendly biofertilizers and environmental cleanup. This approach presents promise for sustainable agriculture and environmental preservation. The current study delves into multiple studies to investigate global pesticide usage levels, primary categorization, and persistence patterns. It also investigates cyanobacterial distribution and their interactions with pesticides in wetland rice ecosystems, aiming to enable their use in sustainable agriculture. Additionally, the review provides a thorough summary of the literature's findings about the potential of cyanobacteria in pesticide degradation.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2025 ","pages":"7265036"},"PeriodicalIF":2.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11978480/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143811122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mixing of Two Microbial Consortia in the Search for Stimulating Chromium Depletion.","authors":"Elcia Margareth Souza Brito, Paola Abigail Martínez-Aldape, Sara Lucia Toscano-Alaniz, César Augusto Caretta, Mónica Jacquelina Martínez-Ramírez, Ramón Eugenio Martínez-Ramírez, Mario Enrique Sandoval-Vergara, Sandra Ixmucamé Concha-Guerrero, Marisol Goñi-Urriza, Alma Hortensia Serafín-Muñoz, Claudia Adriana Ramírez-Valdespino, Rémy Guyoneaud","doi":"10.1155/ijm/8555038","DOIUrl":"https://doi.org/10.1155/ijm/8555038","url":null,"abstract":"<p><p>Two bacterial consortia (C55 and C33), obtained from an industrial residue contaminated with hexavalent chromium (Cr(VI)), were used to study the behavior of their mixture for depleting this ion in liquid media. In the absence of Cr(VI), C55 showed a greater growth rate than C33, while the latter exhibited biofilm formation. In the presence of this ion, C55 showed resistance up to 800 mg·L^-1 and an ability to diminish up to 400 mg·L^-1 of the Cr(VI) from the medium, while for C33, these concentrations were 400 and 200 mg·L^-1, respectively. Bacterial synergism between these consortia was evaluated using different compound ratios (C55:C33 ratios of 1:1, 1:2, and 2:1), growing at 50, 100, and 200 mg·L^-1 Cr(VI). The best half-lives of Cr(VI) decrease were 16, 31, and 98 h, respectively, for the 1:1 mixture. The ability of C33 and the mixed consortia to form biofilms was verified. MiSeq sequencing revealed 4 major populations for C55 (in a total of 14) and 3 for C33 (8), most of which were common. After an isolation process, 2 bacterial strains were obtained from C55 and 4 from C33. Three of these strains (QRePLB33E, similar to <i>Oceanobacillus profundus</i>; QRePLB33G, to <i>Shouchella clausii</i>; and QRePLB55C, to <i>Cellulosimicrobium funkei</i>) showed resistance to Cr(VI) and the ability to remove 100% of it at least up to 300 mg·L^-1. Thus, synergism between different bacterial consortia obtained from the same site is possible and can improve, by complementing their capacities, both the growth rate and the ability to diminish the xenobiotic from the medium.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2025 ","pages":"8555038"},"PeriodicalIF":2.8,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11976035/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143811129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis of a Novel Sepiolite-Ag-Propolis Nanocomposite and Its Effect on the Growth of <i>Aspergillus flavus</i>.","authors":"Elham Rezvannejad, Maryam Fayazi, Batool Sadeghi, Azadeh Boustan, Safa Lotfi","doi":"10.1155/ijm/7371265","DOIUrl":"10.1155/ijm/7371265","url":null,"abstract":"<p><p>Since aflatoxin produced by <i>Aspergillus flavus</i> carries significant impacts on the livestock and poultry industries in terms of animal health and food safety. It is very important to find nonchemical antifungal agents. For this purpose, in this study, bee propolis and its nanocomposites with sepiolite and Ag nanoparticles were investigated for antifungal activity with respect to their use as safer alternatives for conventional antifungal treatments. In the present study, two newly synthesized sepiolite-propolis and sepiolite-Ag-propolis nanocomposite formulations were characterized with different analytical techniques such as XRD, TEM, FTIR, and EDAX. The antifungal potential was determined against <i>A. flavus</i> by the disc diffusion method, and MIC-MFC values were determined. The pure propolis extract had only limited antifungal activity at concentrations up to 400 mg/mL. However, prominent antifungal activities were observed for nanocomposites with propolis, sepiolite, and Ag nanoparticles, as inhibition was observed even at a low concentration of 200 mg/mL. The sepiolite-Ag-propolis nanocomposite outperformed others by increasing the diameter of inhibition zones proportionally with the increase in concentration. The finding results indicate that propolis-based nanocomposites, especially when combined with Ag nanoparticles, hold a promise for antifungal action against <i>A. flavus</i>. Further work is necessary to test their practical value in agricultural and food safety contexts.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2025 ","pages":"7371265"},"PeriodicalIF":2.8,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11957862/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143752609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antibiotic-Resistant <i>Salmonella</i> Enteritidis in Raw Chicken Meat of Dhaka City, Bangladesh.","authors":"Shah Jungy Ibna Karim, K B M Saiful Islam, M Rubaiyat Adnan, Md Abir Hassan Sadi, Mahfuzul Islam","doi":"10.1155/ijm/5654730","DOIUrl":"10.1155/ijm/5654730","url":null,"abstract":"<p><p>Foodborne zoonotic <i>Salmonella</i> is transmitted through contaminated meat, milk, and eggs. This study is aimed at investigating the antimicrobial resistance (AMR) profile of <i>Salmonella</i> Enteritidis isolated from raw chicken meat in Dhaka City, Bangladesh. Two hundred raw chicken meat samples were aseptically collected from 20 retail markets located in Dhaka City, and the isolated <i>Salmonella</i> species were identified based on their morphological, cultural, biochemical, and molecular characterization by polymerase chain reaction (PCR). The primer sets of the <i>Inv</i>A and Enteritidis-specific STM3098 gene were used for the PCR detection of <i>Salmonella</i> species and <i>S.</i> Enteritidis, respectively. The isolates were then screened for AMR phenotypically and the presence of the tetracycline resistance (<i>Tet</i>A) gene. The prevalence of <i>Salmonella</i> species and <i>S.</i> Enteritidis was 22.5% (<i>n</i> = 45/200) and 18.5% (<i>n</i> = 37/200), respectively. However, the prevalence was constant across all the sample markets (<i>p</i> > 0.05). Tetracycline, amoxicillin, and ampicillin resistance was phenotypically present in all isolates (100%). Furthermore, approximately 70%, 49%, and 30% of <i>S.</i> Enteritidis showed resistance against erythromycin, amoxicillin/clavulanic acid, and ciprofloxacin, respectively. However, <i>S.</i> Enteritidis were sensitive to gentamicin (86.5%), meropenem (64.9%), ciprofloxacin (62.2%), and ceftriaxone (59.5%). The <i>Tet</i>A gene, which causes AMR against tetracycline, was shown to be present in all phenotypically resistant <i>Salmonella</i> species. Multiple antibiotic resistance index (MARI) ranged between 0.3 and 0.8. Overall, multidrug resistant (MDR) <i>Salmonella</i> Enteritidis emerged in the chicken meat along with the presence of a resistance gene that is a threat to human health. Therefore, action must be taken to stop the spread of AMR.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2025 ","pages":"5654730"},"PeriodicalIF":2.8,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11955290/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143752605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Yi Mai Granule Improves High-Fat Diet-Induced Nonalcoholic Fatty Liver Disease in Mice by Regulating Gut Microbiota and Metabolites.","authors":"Linlin Pang, Yongming Liu, Changbin Yuan, Yetao Ju, Junpeng Wu, Meijia Cheng, Sian Jin, Ying Fan, Huiyong Zhang, Yu Wang, Dongyu Min","doi":"10.1155/ijm/2273986","DOIUrl":"10.1155/ijm/2273986","url":null,"abstract":"<p><p>Yi Mai granule (YMG) is a traditional Chinese medicine (TCM) herbal decoction consisting of two TCM formulas: Gua-Lou-Ban-Xia decoction and Si-Jun-Zi decoction. YMG has shown clinical benefit in the treatment of nonalcoholic fatty liver disease (NAFLD), which may be due to its regulatory effects on lipid metabolism. Previous studies have highlighted the importance of the gut microbiota and its metabolites in the use of TCM. However, the effect of YMG on the gut microbiota in the treatment of NAFLD remains unclear. In this study, we established an NAFLD model in <i>ApoE^-/-</i> mice and treated them with YMG. High-performance liquid chromatography was adopted to identify the chemical components of YMG. By mapping the candidate targets using network pharmacology, we found that the targets of the main components of YMG were significantly enriched in NAFLD-related pathways. Moreover, <i>16S rRNA</i> gene sequencing revealed that YMG affected the constitution and metabolism of the gut microbiota in NAFLD model mice, including lipid and carbohydrate metabolism. Similarly, metabolites related to lipid and carbohydrate metabolism in mouse serum were significantly altered by YMG. The correlation heat map and network analyses showed that the gut microbiota and metabolites affected by YMG were closely related to the blood lipid content. Collectively, YMG may exert therapeutic effects by affecting the metabolism of gut microbiota, thus regulating lipid and carbohydrate metabolism. These findings offer novel insight into the pharmacological mechanism of YMG in the treatment of NAFLD and provide theoretical bases for its clinical applications.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2025 ","pages":"2273986"},"PeriodicalIF":2.8,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11955292/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143752612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unveiling the Genetic Landscape of <i>Staphylococcus aureus</i> Isolated From Hospital Wastewaters: Emergence of Hypervirulent CC8 Strains in Tehran, Iran.","authors":"Fatemeh Sadat Tabatabaie Poya, Mirmohammad Miri, Zahra Salehi, Mohammad Javad Nasiri, Masoud Dadashi, Mehdi Goudarzi","doi":"10.1155/ijm/5458315","DOIUrl":"10.1155/ijm/5458315","url":null,"abstract":"<p><p><b>Objective(s):</b> Multidrug-resistant bacteria and priority pathogens, including MRSA, are frequently found in hospital wastewaters. It is crucial to investigate the genetic diversity, biofilm formation, and virulence analysis of <i>Staphylococcus aureus</i> isolated from hospital wastewaters. <b>Materials and Methods:</b> In this cross-sectional study, 70 <i>S. aureus</i> isolated from hospital wastewaters were subjected to characterization through antimicrobial susceptibility tests, biofilm formation, multilocus sequence typing (MLST), and PCR analysis for detecting resistance (<i>mecA</i>, <i>mecC</i>, <i>vanA</i>, <i>vanB</i>, <i>mupB</i>, <i>mupA</i>, <i>msr(A)</i>, <i>msr(B)</i>, <i>erm</i>(A), <i>erm</i>(B), <i>erm</i>(C), <i>tet</i>(M), <i>ant</i> (4⁣')<i>-Ia</i>, <i>aac</i> (6⁣')<i>-Ie/aph</i> (2⁣^″), and <i>aph</i> (3⁣')<i>-IIIa</i>) and virulence genes (<i>eta</i>, <i>etb</i>, <i>pvl</i>, and <i>tst</i>). <b>Results:</b> Our results showed that 55.7%, 31.4%, and 12.9% of isolates were classified as strong, intermediate, and weak biofilm-forming strains, respectively. Our result revealed that about three-quarters of isolates harbored <i>mecA</i> (100%), <i>ant</i> (4⁣')<i>-Ia</i> (100%), <i>tet</i>(M) (92.9%), <i>erm</i>(B) (80%), and <i>msr</i>(A) (74.3%) resistance genes. MLST revealed that the 70 isolates belonged to five clonal complexes, including CC8 (52.9%), followed by CC30 (15.7%), CC5 (14.3%), CC1 (11.4%), and CC22 (5.7%). The vast majority of <i>S. aureus</i> isolates belonged to CC8/ST239-MRSA (21.5%). Among the 39 strong biofilm producers, the majority (25.6%) belonged to CC8/ST239-MRSA clone. Our result revealed that about one-third of Panton-Valentine leukocidin (PVL)-positive strains belonged to CC30/ST30. The high-level mupirocin-resistant (HLMUPR) isolates belonged to CC8/ST239-MRSA (36%), CC30/ST30-MRSA (16%), CC8/ST8-MRSA (12%), CC5/ST5-MRSA (12%), CC8/ST585-MRSA (8%), CC5/ST225-MRSA (8%), CC5/ST1637-MRSA (4%), and CC8/ST1465-MRSA (4%) lineages carrying <i>mupA</i>. The VRSA strain belonged to the CC8/ST239-MRSA, CC8/ST8-MRSA, and CC22/ST22-MRSA clonal lineages, carrying the <i>vanA</i> determinant. <b>Conclusion:</b> These findings highlight significant genotypic diversity and high biofilm formation among our isolates. From this study, we identified highly virulent strains of <i>S. aureus</i> associated with biofilm production and drug resistance; some of these strains were highly similar, highlighting the possibility of rapid spread. The high prevalence of CC8 and CC30 clones among <i>S. aureus</i> strains reflects the emergence of these lineages as successful clones in hospital wastewaters in Iran, which is a serious concern. The study highlights the importance of wastewater surveillance to understand genetic pattern and antimicrobial resistance profiles in surrounding communities, which can in turn support public health efforts.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2025 ","pages":"5458315"},"PeriodicalIF":2.8,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11925629/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143669714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Green Nanotechnology: Naturally Sourced Nanoparticles as Antibiofilm and Antivirulence Agents Against Infectious Diseases.","authors":"Habiba Lawal, Shamsaldeen Ibrahim Saeed, Mohammed Sani Gaddafi, Nor Fadhilah Kamaruzzaman","doi":"10.1155/ijm/8746754","DOIUrl":"10.1155/ijm/8746754","url":null,"abstract":"<p><p>The escalating threat of infectious diseases, exacerbated by antimicrobial resistance (AMR) and biofilm formation, necessitates innovative therapeutic strategies. This review presents a comprehensive exploration of the potential of nanoparticles synthesized from natural sources, including plant extracts, microbial products, and marine compounds, as antimicrobial agents. These naturally derived nanoparticles demonstrated significant antibiofilm and antivirulence effects, with specific examples revealing their capacity to reduce biofilm mass by up to 78% and inhibit bacterial quorum sensing by 65%. The integration of bioactive compounds, such as polyphenols and chitosan, facilitates nanoparticle stability and enhances antimicrobial efficacy, while green synthesis protocols reduce environmental risks. Notably, the review identifies the potential of silver nanoparticles synthesized using green tea extracts, achieving 85% inhibition of polymicrobial growth in vitro. Despite these promising results, challenges such as standardization of synthesis protocols and scalability persist. This study underscores the transformative potential of leveraging naturally sourced nanoparticles as sustainable alternatives to conventional antimicrobials, offering quantitative insights for their future application in combating mono- and polymicrobial infections.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2025 ","pages":"8746754"},"PeriodicalIF":2.8,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11876540/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143556664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antimicrobial Susceptibility Profile and Extended-Spectrum Beta-Lactamase Phenotype of <i>E. coli</i> Isolated From Poultry.","authors":"Matilda Ayim-Akonor, Rita Ohene Larbi, Doreen Dela Owusu-Ntumy, Benjamin Kissi Sasu, Hilda Emefa Ohene Asa, Theophilus Odoom","doi":"10.1155/ijm/9468425","DOIUrl":"https://doi.org/10.1155/ijm/9468425","url":null,"abstract":"<p><p>Bacterial resistance to antibiotics is increasing globally, with the food-animal sector (FAS) playing a key role. Knowledge of the antimicrobial resistance (AMR) of microbes from the FAS is important in the development of country-specific methods to minimize the AMR burden. In Ghana, there is limited data on the susceptibility of FAS bacteria to frequently used antimicrobials. We evaluated the susceptibility of 58 <i>Escherichia coli</i> isolates obtained from chickens to nine antibiotics and further assessed their potential to produce extended-spectrum beta-lactamase (ESBL). The Kirby-Bauer disc diffusion and combined disc methods were used following the Clinical and Laboratory Standards Institute guidelines. Nearly all isolates showed high resistance (> 50%) to all the antibiotics except gentamicin, to which more than two-thirds (<i>n</i> = 48, 83%) were susceptible. Resistance to streptomycin, tetracycline, and ampicillin was observed to be 93%, 97%, and 100%, respectively. All isolates were multidrug resistant. Over one-third of the isolates (<i>n</i> = 22, 37.9%) were resistant to seven classes of antibiotics, and a substantial proportion (<i>n</i> = 12, 20.7%) exhibited resistance to all eight antimicrobial classes. None of the isolates was detected as an ESBL producer. Most farms (86%) did not have a footbath, and the majority (71%) changed the bedding material after 4 weeks. Free-range chickens were kept on 80% of the farms. The high resistance to frequently used antibiotics suggests long-term use of these antimicrobials, which may be attributed to poor biosecurity practices that may be exposing the birds to frequent infections. There is a need to educate farmers on the prudent use of antibiotics and adherence to good biosecurity practices.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2025 ","pages":"9468425"},"PeriodicalIF":2.8,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11871970/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143542003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of Combined Irradiation Mutagenesis Technique for Hyperproduction of Surfactin in <i>Bacillus velezensis</i> Strain AF_3B.","authors":"Syeda Amna Farooq, Shazia Khaliq, Saeed Ahmad, Neelma Ashraf, Muhammad Afzal Ghauri, Munir Ahmad Anwar, Kalsoom Akhtar","doi":"10.1155/ijm/5570585","DOIUrl":"10.1155/ijm/5570585","url":null,"abstract":"<p><p>The major challenge in large-scale industrial use of lipopeptide surfactin is the low yield by indigenous bacterial strains and the higher cost of its production that have been proved as a limiting factor in commercial applications. Therefore, there is an urgent demand for high-yielding strains that can be achieved through strain improvement. A first report on the use of a combination of UV and gamma-irradiation mutagenesis for the development of surfactin hyperproducing mutants of <i>Bacillus</i> spp. proved to be significant and resulted in a twofold enhancement in surfactin yield. The mutant was able to grow and produce surfactin on all the tested carbon and nitrogen sources, while 2% glycerol favored maximum surfactin yield (1.62 g/L) as compared to the wild-type strain that showed a maximum 0.85 g/L surfactin yield at 3% sucrose. Additionally, the mutant exhibited a good yield of pure surfactin, that is, 1.55 g/L as compared to the wild strain (0.411 g/L) by using corn steep liquor as the main component of the fermentation medium. The study concluded overall a threefold enhancement in the relative abundance of purified surfactin and its isoforms detected by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) analysis in mutant strain AF-UV<i>γ</i>2500.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2025 ","pages":"5570585"},"PeriodicalIF":2.8,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11867730/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143523460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Expression of Resuscitation-Promoting Factor C Stimulates the Growth of <i>Mycobacterium bovis</i> BCG and Delays DevR Regulon Activation in Hypoxia.","authors":"Luz Virginia Reyes-González, Olga N Hernández de la Cruz, Mauricio Castañón-Arreola","doi":"10.1155/ijm/2139933","DOIUrl":"10.1155/ijm/2139933","url":null,"abstract":"<p><p>Latent tuberculosis is characterized by the presence of dormant, nonreplicating (DNR) bacilli for years without causing clinical signs and symptoms, remaining as a major reservoir for active tuberculosis. The mechanism through which <i>M. tuberculosis</i> transits from DNR to active bacilli remains unclear. However, resuscitation-promoting factors (Rpfs) could participate in the reactivation. Using recombinant <i>M. bovis</i> BCG that expresses <i>rpfC</i> (<i>M. bovis</i> BCG-pMV261::<i>rpfC</i>), we evaluated the role of RpfC in the growth of bacilli and the expression of 11 hypoxia-regulated genes in comparison with <i>M. bovis</i> BCG-pMV261. The strains were grown in normoxic (21% O₂), hypoxic (5% O₂), and anoxic (< 0.1% O₂) conditions. In normoxic culture, <i>M. bovis</i> BCG-pMV261::<i>rpfC</i> displays a lower expression of <i>sigB</i> and <i>fdxA.</i> In anoxic culture, we did not observe drastic changes in the gene expression, except for those involved in electron transport during anaerobic respiration (<i>pdxA</i>, <i>pfkB,</i> and <i>nark2</i>), whose expression was significantly lower in <i>M. bovis</i> BCG-pMV261. When the strains were cultured in hypoxia, significantly higher culturability was observed in <i>M. bovis</i> BCG-pMV261::<i>rpfC</i> compared to <i>M. bovis</i> BCG-pMV261. This response was accompanied by a higher <i>sigB</i> and <i>sigE</i> expression. In both strains, we observed a higher <i>dosT, devR, fdxA,</i> and <i>fpkB</i> expression in response to hypoxia. Interestingly, except for <i>fdxA,</i> the expression of these genes was lower in <i>M. bovis</i> BCG-pMV261::<i>rpfC</i>. The protein profiles of <i>M. bovis</i> BCG-pMV261::<i>rpfC</i> reflected the maintenance of an active replicative state (similar to that of the strain grown in normoxic conditions). In anoxic cultures, no significant changes were observed in the expression of hypoxia-response genes. These findings suggest that <i>rpfC</i> may have a significant physiological role in inducing the growth of <i>M. bovis</i> BCG-pMV261::<i>rpfC,</i> which results in the delayed activation of genes related to the transition to anaerobic metabolism.</p>","PeriodicalId":14098,"journal":{"name":"International Journal of Microbiology","volume":"2025 ","pages":"2139933"},"PeriodicalIF":2.8,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11850072/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143492106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}