Luan Amaral Alexandre, Alice Cristina da Silva, Francisco Lucas de Amorim Nascimento, Ana Paula Zapelini de Melo, Silvani Verruck
{"title":"Antimicrobial resistance of Escherichia coli isolated from fish and aquaculture water: an emerging concern for consumers.","authors":"Luan Amaral Alexandre, Alice Cristina da Silva, Francisco Lucas de Amorim Nascimento, Ana Paula Zapelini de Melo, Silvani Verruck","doi":"10.1093/lambio/ovaf099","DOIUrl":"https://doi.org/10.1093/lambio/ovaf099","url":null,"abstract":"<p><p>Antimicrobial resistance (AMR) constitutes a significant global health threat, exacerbated using antimicrobials in aquaculture, which accelerates the spread of resistant bacteria. In fish and aquaculture water, Escherichia coli acts as a key reservoir and vector for AMR, facilitating the dissemination of strains resistant to critically important antibiotics like carbapenems and colistin, often through the production of enzymes such as extended-spectrum ß-lactamases (ESBLs). This review aimed to synthesize recent findings on AMR patterns and associated genes in E. coli from fish and aquaculture waters globally. Studies indicate a high prevalence of resistant E. coli, with MDR to β-lactams, tetracyclines, quinolones, and sulfonamides. Common resistance genes identified include blaTEM, blaCTX-M, tet(A), sul1, and qnrS. The presence of bacterial strains harboring these resistance genes poses a significant public health risk through transmission in the food chain and the environment. The study concludes that tackling this challenge effectively demands robust surveillance, optimized aquaculture management, responsible antimicrobial stewardship, and a cohesive One Health framework aimed at reducing AMR in aquaculture and preserving public health.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144690594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Targeting Plasmodium Glutathione S-transferases to Overcome Antimalaria Drug Resistance in Southern Africa.","authors":"Sarah Otun, Ikechukwu Achilonu","doi":"10.1093/lambio/ovaf100","DOIUrl":"https://doi.org/10.1093/lambio/ovaf100","url":null,"abstract":"<p><p>Southern Africa remains burdened by malaria, with growing concern about the emergence of antimalarial drug resistance. While artemisinin resistance has not yet been observed in the region, molecular surveillance in sub-Saharan Africa has identified Plasmodium falciparum k13 mutations known to confer resistance, making it vitally important to take proactive and creative measures to protect current treatment regimens. Glutathione S-transferases (GSTs), the multifunctional enzymes involved in detoxification and redox control, have emerged as key contributors to drug resistance in Plasmodium species. The role of GSTs in the development of resistance is discussed in the review, and GSTs are presented as prospective molecular targets for the development of novel therapeutic interventions. We examine the complexity of antimalarial resistance in Southern Africa and highlight the potential of GST inhibition as an adjunct therapy to current malaria control measures. The review promotes a paradigm shift towards GST-targeting approaches as a pre-emptive strategy to avert resistance and consolidate malaria control initiatives throughout the region, aligning with Sustainable Development Goal 3 (Good health and wellbeing) among Southern African populations.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144690595","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Aliyu Ibrahim Dabai, Raghavendra Juluri Rao, Anna Kulakov, Shamsudeen Umar Dandare, Rory Doherty, Mathew Boyd, Christopher C R Allen
{"title":"Developing a Molecular Tool for Evaluating the Status of Petrochemical-Contaminated Soils Using functional Gene Ratio Strategy.","authors":"Aliyu Ibrahim Dabai, Raghavendra Juluri Rao, Anna Kulakov, Shamsudeen Umar Dandare, Rory Doherty, Mathew Boyd, Christopher C R Allen","doi":"10.1093/lambio/ovaf097","DOIUrl":"https://doi.org/10.1093/lambio/ovaf097","url":null,"abstract":"<p><p>Petrochemical spills present a global environmental challenge, necessitating effective monitoring and remediation. This study was designed to develop a molecular tool using binary functional gene ratios to assess contamination levels and timelines in petrochemical-contaminated soils. Soils from petrochemical-contaminated sites were collected and hydrocarbon quantification was performed using GC-MS and GCxGC-FID, against specific standards. Metagenomic DNA was extracted, and functional genes associated with hydrocarbon degradation (PAH Ring-hydroxylating dioxygenase (PAH-RHDα) and 6-oxocyclohex-1-ene-1-carbonyl-CoA hydrolase (bamA)) were analysed using qPCR. A diagnostic ratio of PAH degradation genes was applied to characterise pollution. In-silico gene mining was used to verify the functional gene ratios. MS revealed distinct contamination profiles correlating with pollution duration and pollutant levels. One set of samples had kerosene concentrations between 154-478.64 µg/g of soil, while the other contained < 11 µg/g. Functional genes analysis linked higher kerosene concentrations to increased gram-negative dioxygenase levels and lower kerosene concentrations to gram-positive dioxygenases. PAH-RHDα-GN: bamA and PAH-RHDα-GP: bamA reflected contamination levels and apparent pollution age. In-silico gene mining validated qPCR findings, confirming the reliability of gene ratios for environmental monitoring. Our findings show that the functional gene ratios serve as a molecular biomarker for spill characterisation, offering a novel approach for assessing and monitoring contamination in soils.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144649853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Integrating metagenomics and high-throughput screening for bioprospecting marine producers of Polyhydroxyalkanoates.","authors":"Naicai Zhong, Yuan Chen, Wenfeng Pan, Hailin Meng, Kun Liang, Jun Lu, Yanlin Jiang, Chenyou Zhong, Muzhi Yang, Yinglei Zhai, Jinyi Zhong","doi":"10.1093/lambio/ovaf096","DOIUrl":"10.1093/lambio/ovaf096","url":null,"abstract":"<p><p>With the escalating global demand for eco-friendly materials, polyhydroxyalkanoates (PHAs) have emerged as promising biodegradable alternatives to conventional plastics. This study base on the systematic investigation of microbial community distribution and functional composition associated with PHA biosynthesis across diverse marine environments through metagenomic analysis. Leveraging environmental characteristics and PHA synthesis potential, we developed targeted culture media. We successfully isolated 102 PHA-producing bacterial strains from various marine habitats, including brackish water interfaces and deep-sea sediments. Gas chromatography (GC) quantification revealed a significant correlation (R²=0.67) between Nile red fluorescence intensity and PHA content in metagenomically-predicted strains, effectively addressing false-positive issues in fluorescence-based screening. We subsequently established a high-throughput screening platform combining microplate technology with fluorometric quantification, identifying 10 elite strains for fermentation optimization and PHA characterization. Notably, strain R1-4-2 (identified as Halomonas olivaria) demonstrated exceptional performance with 2.59 g L-1 cell dry weight (CDW) and 52.89% PHA content (1.52 g L-1 CDW), representing both a novel microbial resource for sustainable PHA production and a potential chassis for synthetic biology applications. These findings provide critical scientific insights and technical frameworks for advancing industrial-scale production of biodegradable biopolymers.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144649854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wei Yi, Mi Wei, Feitong Li, Longyu Wang, Jian He, Ang Ren, Ailiang Jiang, Ran Tao, Bangchao Zhong, Qin He
{"title":"Water Supply from Various Sources has Different Effects on Solid-State Fermentation of Ganoderma lucidum.","authors":"Wei Yi, Mi Wei, Feitong Li, Longyu Wang, Jian He, Ang Ren, Ailiang Jiang, Ran Tao, Bangchao Zhong, Qin He","doi":"10.1093/lambio/ovaf095","DOIUrl":"https://doi.org/10.1093/lambio/ovaf095","url":null,"abstract":"<p><p>Water is essential in solid-state fermentation (SSF), but the impact of different water sources on SSF efficiency remains unclear. This study investigated the effects of different water sources on water-supply SSF of Ganoderma lucidum. The results showed that supplementation with normal saline led to the highest levels of laccase, CMCase, FPA activities, and biomass of Ganoderma lucidum (93.47, 140.34, 172.42 U/g, and 0.19 g/g, respectively), almost all significantly higher than those in the tap water group (83.57, 126.36, 167.17 U/g, and 0.18 g/g) and the deionized water group (77.25, 120.91, 145.50 U/g, and 0.16 g/g). Normal saline also significantly increased the capillary water content during SSF, which was 5.38% and 19.05% higher than that in the tap water and deionized water groups, respectively. Furthermore, the relaxation time of capillary water in the normal saline group decreased by 49.09%, a reduction that was higher than those observed in the tap water group (43.41%) and the deionized water group (29.56%). In conclusion, normal saline demonstrated distinct advantages in enhancing SSF efficiency, thus providing a scientific basis for the selection of water sources in the fermentation of G. lucidum and other microorganisms.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144642896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Molecular mechanisms of heavy metal resistance and cross-/co-resistance to antibiotics in Pseudomonas aeruginosa.","authors":"Bilel Hassen, Mohamed Salah Abbassi","doi":"10.1093/lambio/ovaf094","DOIUrl":"https://doi.org/10.1093/lambio/ovaf094","url":null,"abstract":"<p><p>Heavy metal pollution is a growing environmental and public health concern, particularly due to its impact on microbial communities. Pseudomonas aeruginosa, a highly adaptable bacterium, has developed resistance to heavy metals (HMs), which is closely linked to antibiotic resistance through shared genetic and regulatory pathways. This co-resistance poses significant challenges for environmental health and antimicrobial management. Additionally, microplastics act as carriers for HMs and antibiotics, creating a compounded pollution stressor that further influences bacterial resistance patterns. This review explores the molecular mechanisms by which P. aeruginosa resists heavy metal toxicity, focusing on key adaptive strategies such as efflux systems, biofilm formation, enzymatic detoxification, and genetic modifications. These mechanisms enhance bacterial survival in contaminated environments, allowing P. aeruginosa to persist and contribute to the spread of resistance genes. The interplay between HMs, antibiotics, and microplastics underscores the complexity of pollution-driven bacterial adaptation. Addressing these issues requires a multidisciplinary approach that integrates environmental pollution control and antimicrobial resistance management. Understanding how P. aeruginosa thrives under such stress conditions is crucial for developing effective strategies to mitigate the risks associated with heavy metal contamination, antibiotic resistance, and microplastic pollution in both natural and clinical ecosystems.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144618713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Katherine Ratliff, Michael Worth Calfee, Ahmed Abdel-Hady, Mariela Monge, Denise Aslett, Lukas Oudejans
{"title":"Impact of inoculum composition on bacteria and bacteriophage UVC inactivation at 222 nm and 254 nm.","authors":"Katherine Ratliff, Michael Worth Calfee, Ahmed Abdel-Hady, Mariela Monge, Denise Aslett, Lukas Oudejans","doi":"10.1093/lambio/ovaf090","DOIUrl":"10.1093/lambio/ovaf090","url":null,"abstract":"<p><p>Using technologies that emit ultraviolet-C (UVC) radiation to inactivate pathogens has gained increasing interest as a strategy for reducing the risk of disease transmission, but it can be difficult to predict their performance in applied settings. Directly irradiating occupied spaces with emerging far-UVC has been proposed, as its shorter wavelength (200-230 nm) is reportedly less damaging to human eyes and skin than longer wavelengths. In this study, we conducted surface tests to evaluate the impact of different inoculum compositions (with and without soil loads) and conditions (wet vs. dried droplets) to determine how these factors affect the efficacy of UVC sources with peak emissions at 254 and 222 nm against five bacteria and two bacteriophages. The presence of a soil load reduced the efficacy of 222-nm UVC more than that at 254 nm, and both UVC sources were generally less effective against microbes in dried (vs. wet) inoculum. Given that pathogens will often be exposed to UVC in the presence of proteins, salts, and other constituents depending on how they are emitted, it is important to consider these challenges when quantifying efficacy.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144528576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Short-chain fatty acids and their role in modulating autoimmune responses in psoriasis: insights from recent microbiota research.","authors":"Narges Fallahi, Mitra Rafiee, Seyedeh Sindokht Hosseini, Nasrin Sereshki, Gholamreza Anani Sarab, Nafiseh Erfanian","doi":"10.1093/lambio/ovaf091","DOIUrl":"10.1093/lambio/ovaf091","url":null,"abstract":"<p><p>Psoriasis, a chronic skin autoimmune disease characterized by abnormal immune responses, is influenced by genetic and environmental factors. Recent microbiota research has revealed that short-chain fatty acids (SCFAs), metabolites produced by gut microbiota, play a pivotal role in regulating immune function and inflammation. This review examines the current literature on the relationship between gut dysbiosis, SCFA production, and immune modulation in psoriasis, focusing on emerging evidence from microbiota and immunological studies. SCFAs have been shown to influence key immune pathways, including T-cell activation and cytokine production, which are critical in psoriasis pathogenesis. Reduced SCFA levels have been observed in psoriasis, highlighting the role of gut dysbiosis in disease progression. Understanding the gut-skin axis and the role of SCFAs offers novel insights into developing effective, safe, and accessible treatments for psoriasis. Restoring microbial balance and SCFA production may serve as a promising therapeutic approach for managing psoriasis.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144484912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Correction to: Comparative analysis of the roles of catalases KatB and KatG in the physiological fitness and pathogenesis of fish pathogen Edwardsiella tarda.","authors":"","doi":"10.1093/lambio/ovaf098","DOIUrl":"https://doi.org/10.1093/lambio/ovaf098","url":null,"abstract":"","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":"78 7","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144707962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Roya Abedi Soleimani, Payam Gonbari Milani, Nader Khani, Aziz Homayouni-Rad
{"title":"The overlooked hazard: Clostridioides difficile in preterm infants and immature immune systems-harnessing postbiotics for safer therapeutic strategies.","authors":"Roya Abedi Soleimani, Payam Gonbari Milani, Nader Khani, Aziz Homayouni-Rad","doi":"10.1093/lambio/ovaf083","DOIUrl":"10.1093/lambio/ovaf083","url":null,"abstract":"<p><p>Clostridioides difficile is a potentially harmful bacterium that can affect preterm infants more seriously than full-term infants, largely due to their immature immune systems and underdeveloped gut microbiota. Although colonization with C. difficile is often harmless in healthy babies, preterm infants are more likely to develop infections, which can lead to serious health problems. This review looks at how an immature immune system and an imbalanced gut microbiome increase the risk of C. difficile infection (CDI) in early life. To reduce this risk, researchers are exploring postbiotics-non-living bacterial products or byproducts-as a safer alternative to traditional treatments like antibiotics. Postbiotics can help by strengthening the gut barrier, reducing inflammation, and supporting the growth of beneficial bacteria. They are also considered safe for use in vulnerable populations, including infants. This review discusses the types of postbiotics, their functions, and how they may help prevent or manage CDI. It also highlights their potential for use in infant formula as a preventative strategy. Overall, postbiotics may offer a promising new way to protect preterm infants from C. difficile and support healthier immune and gut development.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144275281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}