Diana H Quan, Trixie Wang, Elena Martinez, Hannah Y Kim, Vitali Sintchenko, Warwick J Britton, James A Triccas, Jan-Willem C Alffenaar
Background: The enormous burden of tuberculosis (TB) worldwide is a major challenge to human health, but the costs and risks associated with novel drug discovery have limited treatment options for patients. Repurposing existing antimicrobial drugs offers a promising avenue to expand TB treatment possibilities. This study aimed to explore the activity and synergy of beta-lactams in combination with a beta-lactamase inhibitor, which have been underutilized in TB treatment to date.
Methods: Based on inhibitory concentration, oral bioavailability, and commercial availability, seven beta-lactams (cefadroxil, tebipenem, cephradine, cephalexin, cefdinir, penicillin V, and flucloxacillin), two beta-lactamase inhibitors (avibactam and clavulanate), and three second-line TB drugs (moxifloxacin, levofloxacin, and linezolid) were selected for combination in vitro testing against Mycobacterium tuberculosis H37Rv. Resazurin assays and colony forming unit enumeration were used to quantify drug efficacy, Chou-Talalay calculations were performed to identify drug synergy and Chou-Martin calculations were performed to quantify drug dose reduction index.
Results: The order of activity of beta-lactams was cefadroxil > tebipenem > cephradine > cephalexin > cefdinir > penicillin V > flucloxacillin. The addition of clavulanate improved beta-lactam activity to a greater degree than the addition of avibactam. As a result, avibactam was excluded from further investigations, which focused on clavulanate. Synergy was demonstrated for cefdinir/cephradine, cefadroxil/tebipenem, cefadroxil/penicillin V, cefadroxil/cefdinir, cephalexin/tebipenem, cephalexin/penicillin V, cephalexin/cefdinir, cephalexin/cephradine, and cefadroxil/cephalexin, all with clavulanate. However, combining beta-lactams with moxifloxacin, levofloxacin, or linezolid resulted in antagonistic effects, except for the combinations of penicillin V/levofloxacin, penicillin V/moxifloxacin, and cefdinir/moxifloxacin.
Conclusions: Beta-lactam synergy may provide viable combination therapies for the treatment of TB.
{"title":"Synergistic oral beta-lactam combinations for treating tuberculosis.","authors":"Diana H Quan, Trixie Wang, Elena Martinez, Hannah Y Kim, Vitali Sintchenko, Warwick J Britton, James A Triccas, Jan-Willem C Alffenaar","doi":"10.1093/jambio/lxae255","DOIUrl":"10.1093/jambio/lxae255","url":null,"abstract":"<p><strong>Background: </strong>The enormous burden of tuberculosis (TB) worldwide is a major challenge to human health, but the costs and risks associated with novel drug discovery have limited treatment options for patients. Repurposing existing antimicrobial drugs offers a promising avenue to expand TB treatment possibilities. This study aimed to explore the activity and synergy of beta-lactams in combination with a beta-lactamase inhibitor, which have been underutilized in TB treatment to date.</p><p><strong>Methods: </strong>Based on inhibitory concentration, oral bioavailability, and commercial availability, seven beta-lactams (cefadroxil, tebipenem, cephradine, cephalexin, cefdinir, penicillin V, and flucloxacillin), two beta-lactamase inhibitors (avibactam and clavulanate), and three second-line TB drugs (moxifloxacin, levofloxacin, and linezolid) were selected for combination in vitro testing against Mycobacterium tuberculosis H37Rv. Resazurin assays and colony forming unit enumeration were used to quantify drug efficacy, Chou-Talalay calculations were performed to identify drug synergy and Chou-Martin calculations were performed to quantify drug dose reduction index.</p><p><strong>Results: </strong>The order of activity of beta-lactams was cefadroxil > tebipenem > cephradine > cephalexin > cefdinir > penicillin V > flucloxacillin. The addition of clavulanate improved beta-lactam activity to a greater degree than the addition of avibactam. As a result, avibactam was excluded from further investigations, which focused on clavulanate. Synergy was demonstrated for cefdinir/cephradine, cefadroxil/tebipenem, cefadroxil/penicillin V, cefadroxil/cefdinir, cephalexin/tebipenem, cephalexin/penicillin V, cephalexin/cefdinir, cephalexin/cephradine, and cefadroxil/cephalexin, all with clavulanate. However, combining beta-lactams with moxifloxacin, levofloxacin, or linezolid resulted in antagonistic effects, except for the combinations of penicillin V/levofloxacin, penicillin V/moxifloxacin, and cefdinir/moxifloxacin.</p><p><strong>Conclusions: </strong>Beta-lactam synergy may provide viable combination therapies for the treatment of TB.</p>","PeriodicalId":15036,"journal":{"name":"Journal of Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142466144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mariana de Fátima Albuquerque Pereira, Larissa Gabriela Morais de Ávila, Bruna Cristina Dos Santos Cruz, Lucas Filipe Almeida, Jordana Macedo Simões, Bruno Campos Silva, Ananda Pereira Aguilar, Leandro Licursi de Oliveira, Reggiani Vilela Gonçalves, Andréa de Oliveira Barros Ribon, Tiago Antônio de Oliveira Mendes, Maria do Carmo Gouveia Peluzio
Aims: Salmonellosis, a major global cause of diarrheal diseases, significantly impacts the intestinal microbiome. Probiotic-rich beverages, such as kefir, are increasingly utilized as alternative health-promoting beverages associated with various microbiota benefits. This study investigated the repercussions of daily consumption of household-produced milk kefir on Salmonella enterica serovar Typhimurium infection in C57BL-6 mice.
Methods and results: Kefir consumption pre infection reduced the presence of inflammatory cells in the colon and altered the cytokine profile by reducing IL-10 and increasing IFN-γ. Despite reducing intestinal inflammation, kefir intake did not yield a prompt response to an acute infection caused by the aggressive pathogen Salmonella. This contributed to increased mortality in the mice, evidenced by higher fecal Salmonella counts post-infection. Metabarcoding analysis demonstrated that the use of kefir before infection increases butyric acid by the higher abundance of Lachnospiraceae and Prevotellaceae families and genus in feces, coupled with an increase in Muribaculaceae family and Bacteroides genus among infected kefir-treated mice. While kefir hinted at microbiota alterations reducing enterobacteria (Helicobacter), decrease IL-10, and increased IFN-γ, butyric acid on pre-infection, the beverage potentially facilitated the systemic translocation of pathogens, intensifying the infection's severity by altering the immune response.
Conclusions: The use of kefir in the dosage of 10% w/v (109 CFU), for acute infections with Salmonella Typhimurium, may not be enough to combat the infection and worsen the prognosis, leaving the intestine less inflamed, favoring the replication and translocation of the pathogen. These findings underscore the importance of prudently evaluating the widespread use of probiotics and probiotic-rich beverages, especially during acute infections, given their potential association with adverse effects during these diseases.
{"title":"Daily Intake of Household-Produced Milk Kefir on Salmonella Typhimurium Infection in C57BL/6 Mice: Mortality, Microbiota Modulation and Immunological Implications.","authors":"Mariana de Fátima Albuquerque Pereira, Larissa Gabriela Morais de Ávila, Bruna Cristina Dos Santos Cruz, Lucas Filipe Almeida, Jordana Macedo Simões, Bruno Campos Silva, Ananda Pereira Aguilar, Leandro Licursi de Oliveira, Reggiani Vilela Gonçalves, Andréa de Oliveira Barros Ribon, Tiago Antônio de Oliveira Mendes, Maria do Carmo Gouveia Peluzio","doi":"10.1093/jambio/lxae249","DOIUrl":"https://doi.org/10.1093/jambio/lxae249","url":null,"abstract":"<p><strong>Aims: </strong>Salmonellosis, a major global cause of diarrheal diseases, significantly impacts the intestinal microbiome. Probiotic-rich beverages, such as kefir, are increasingly utilized as alternative health-promoting beverages associated with various microbiota benefits. This study investigated the repercussions of daily consumption of household-produced milk kefir on Salmonella enterica serovar Typhimurium infection in C57BL-6 mice.</p><p><strong>Methods and results: </strong>Kefir consumption pre infection reduced the presence of inflammatory cells in the colon and altered the cytokine profile by reducing IL-10 and increasing IFN-γ. Despite reducing intestinal inflammation, kefir intake did not yield a prompt response to an acute infection caused by the aggressive pathogen Salmonella. This contributed to increased mortality in the mice, evidenced by higher fecal Salmonella counts post-infection. Metabarcoding analysis demonstrated that the use of kefir before infection increases butyric acid by the higher abundance of Lachnospiraceae and Prevotellaceae families and genus in feces, coupled with an increase in Muribaculaceae family and Bacteroides genus among infected kefir-treated mice. While kefir hinted at microbiota alterations reducing enterobacteria (Helicobacter), decrease IL-10, and increased IFN-γ, butyric acid on pre-infection, the beverage potentially facilitated the systemic translocation of pathogens, intensifying the infection's severity by altering the immune response.</p><p><strong>Conclusions: </strong>The use of kefir in the dosage of 10% w/v (109 CFU), for acute infections with Salmonella Typhimurium, may not be enough to combat the infection and worsen the prognosis, leaving the intestine less inflamed, favoring the replication and translocation of the pathogen. These findings underscore the importance of prudently evaluating the widespread use of probiotics and probiotic-rich beverages, especially during acute infections, given their potential association with adverse effects during these diseases.</p>","PeriodicalId":15036,"journal":{"name":"Journal of Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142347155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yang Liu,Siew Ling Ong,Kristene Gedye,Mauro Truglio,Sujay Prabakar
AIMSThe leather industry is embracing eco-friendly technologies for both regulatory compliance and sustainable growth. While enzymatic depilation provides a greener alternative to traditional beamhouse methods, its complexity often leads to higher costs. To address this, we examined the performance of sheepskins' native bacterial flora in acetic acid conditions with low environmental impact.METHODS AND RESULTSUtilizing metagenomic techniques, we analyzed the bacterial community dynamics during the depilation process. This investigation revealed a notable increase in microbial diversity and richness in acetic acid treatments compared to water treatments. At the class level, a post-processing decrease in Gammaproteobacteria dominance was observed, while Actinomycetia numbers surged in the acetic acid group. In contrast, the water group showed an increase in Bacteroidia. Order-level analysis indicated reductions in Pseudomonadales and increases in Actinomycetales with acetic acid treatment, whereas Flavobacteriales was more prevalent in water-treated liquors. At the family level, Moraxellaceae decreased and Micrococcaceae increased in the acetic acid group, in contrast to the marked rise of Weeksellaceae in the water group. Temporal analyses further highlighted the evolving bacterial landscapes under different treatments. Moreover, acetic acid treatment fostered a stable microbial community, beneficial for sustainable leather processing. Functional pathways were predicted using PICRUSt2. It showed that significantly enriched degradation pathways in the water group were less abundant in the acetic acid group, potentially preventing substrate matrix damage during depilation.CONCLUSIONSThe study underscores the transformative potential of acetic acid for the leather industry, offering a pathway to reduce pollution while maintaining economic viability. By enhancing our understanding of microbial interactions during depilation, this study opens avenues for refining these eco-friendly techniques. Our findings advocate for a shift towards greener depilation methods and contribute to the broader dialogue on sustainable manufacturing practices, emphasizing the importance of leveraging indigenous microbial communities for environmental and economic gains.
{"title":"Behind the Scenes: Metagenomic Analysis of Bacterial Communities in Sustainable Depilation of Sheepskin.","authors":"Yang Liu,Siew Ling Ong,Kristene Gedye,Mauro Truglio,Sujay Prabakar","doi":"10.1093/jambio/lxae244","DOIUrl":"https://doi.org/10.1093/jambio/lxae244","url":null,"abstract":"AIMSThe leather industry is embracing eco-friendly technologies for both regulatory compliance and sustainable growth. While enzymatic depilation provides a greener alternative to traditional beamhouse methods, its complexity often leads to higher costs. To address this, we examined the performance of sheepskins' native bacterial flora in acetic acid conditions with low environmental impact.METHODS AND RESULTSUtilizing metagenomic techniques, we analyzed the bacterial community dynamics during the depilation process. This investigation revealed a notable increase in microbial diversity and richness in acetic acid treatments compared to water treatments. At the class level, a post-processing decrease in Gammaproteobacteria dominance was observed, while Actinomycetia numbers surged in the acetic acid group. In contrast, the water group showed an increase in Bacteroidia. Order-level analysis indicated reductions in Pseudomonadales and increases in Actinomycetales with acetic acid treatment, whereas Flavobacteriales was more prevalent in water-treated liquors. At the family level, Moraxellaceae decreased and Micrococcaceae increased in the acetic acid group, in contrast to the marked rise of Weeksellaceae in the water group. Temporal analyses further highlighted the evolving bacterial landscapes under different treatments. Moreover, acetic acid treatment fostered a stable microbial community, beneficial for sustainable leather processing. Functional pathways were predicted using PICRUSt2. It showed that significantly enriched degradation pathways in the water group were less abundant in the acetic acid group, potentially preventing substrate matrix damage during depilation.CONCLUSIONSThe study underscores the transformative potential of acetic acid for the leather industry, offering a pathway to reduce pollution while maintaining economic viability. By enhancing our understanding of microbial interactions during depilation, this study opens avenues for refining these eco-friendly techniques. Our findings advocate for a shift towards greener depilation methods and contribute to the broader dialogue on sustainable manufacturing practices, emphasizing the importance of leveraging indigenous microbial communities for environmental and economic gains.","PeriodicalId":15036,"journal":{"name":"Journal of Applied Microbiology","volume":"34 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
AIMSThe immense therapeutic value of Valeriana jatamansi is attributed to the presence of bioactive secondary metabolites (valepotriates and sesquiterpenoids). Its over-exploitation in wild habitats resulted in extensive depletion, necessitating alternative approaches to produce its therapeutic metabolites. This study sought to assess the ability of endophytes of V. jatamansi to boost the biosynthesis of secondary metabolites in the leaf-cell suspension (LCS) culture of V. jatamansi.METHODS AND RESULTSA total of 11 fungal endophytes were isolated from the rhizomes of V. jatamansi. Isolated endophytes were found to belong to phylum Ascomycota, Basidiomycota, and Mucoromycota. Supplementation of extracts of endophyte Phaeosphaeriaceae sp. VRzFB, Mucor griseocyanus VRzFD, Penicillium raistrickii VRzFK, and Penicillium sajarovii VRzFL in the LCS culture of V. jatamansi increased the fresh cell biomass by 19.6-39.1% and dry cell biomass by 23.4-37.8%. Most of the endophytes' extract could increase the content of valepotriates (26.5-76.5% valtrate and 40.5-77.9% acevaltrate) and sesquiterpenoids (19.9-61.1% hydroxyl valerenic acid) in LCS culture. However, only two endophytes Irpex lacteus VRzFI and Fusarium oxysporum VRzFF could increase the sesquiterpenoids acetoxy valerenic acid (36.9-55.3%). In contrast, some endophytes' extracts caused negative or no significant effect on the cell biomass and targeted metabolites. Increased secondary metabolites were corroborated with increased expression of iridoid biosynthesis genes in LCS culture. Production of H2O2 and lipid peroxidation was also varied with different endophytes indicating the modulation of cellular oxidative stress due to endophyte elicitors.CONCLUSIONSThe results suggest the distinct effect of different fungal endophytes-extract on LCS culture, and endophytes can serve as biotic elicitors for increasing the secondary metabolite production in plant in-vitro systems.
{"title":"Endophyte-based fungal elicitors for enhanced production of valepotriates and sesquiterpenoids in leaf cell suspension cultures of Valeriana jatamansi Jones.","authors":"Ankita Thakur,Kanika Thakur,Anil Kumar,Ashish Rambhau Warghat,Dinesh Kumar,Shiv Shanker Pandey","doi":"10.1093/jambio/lxae242","DOIUrl":"https://doi.org/10.1093/jambio/lxae242","url":null,"abstract":"AIMSThe immense therapeutic value of Valeriana jatamansi is attributed to the presence of bioactive secondary metabolites (valepotriates and sesquiterpenoids). Its over-exploitation in wild habitats resulted in extensive depletion, necessitating alternative approaches to produce its therapeutic metabolites. This study sought to assess the ability of endophytes of V. jatamansi to boost the biosynthesis of secondary metabolites in the leaf-cell suspension (LCS) culture of V. jatamansi.METHODS AND RESULTSA total of 11 fungal endophytes were isolated from the rhizomes of V. jatamansi. Isolated endophytes were found to belong to phylum Ascomycota, Basidiomycota, and Mucoromycota. Supplementation of extracts of endophyte Phaeosphaeriaceae sp. VRzFB, Mucor griseocyanus VRzFD, Penicillium raistrickii VRzFK, and Penicillium sajarovii VRzFL in the LCS culture of V. jatamansi increased the fresh cell biomass by 19.6-39.1% and dry cell biomass by 23.4-37.8%. Most of the endophytes' extract could increase the content of valepotriates (26.5-76.5% valtrate and 40.5-77.9% acevaltrate) and sesquiterpenoids (19.9-61.1% hydroxyl valerenic acid) in LCS culture. However, only two endophytes Irpex lacteus VRzFI and Fusarium oxysporum VRzFF could increase the sesquiterpenoids acetoxy valerenic acid (36.9-55.3%). In contrast, some endophytes' extracts caused negative or no significant effect on the cell biomass and targeted metabolites. Increased secondary metabolites were corroborated with increased expression of iridoid biosynthesis genes in LCS culture. Production of H2O2 and lipid peroxidation was also varied with different endophytes indicating the modulation of cellular oxidative stress due to endophyte elicitors.CONCLUSIONSThe results suggest the distinct effect of different fungal endophytes-extract on LCS culture, and endophytes can serve as biotic elicitors for increasing the secondary metabolite production in plant in-vitro systems.","PeriodicalId":15036,"journal":{"name":"Journal of Applied Microbiology","volume":"6 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Paola Di Fermo,Firas Diban,Elisabetta Ancarani,Kelvin Yu,Sara D'Arcangelo,Simonetta D'Ercole,Silvia Di Lodovico,Mara Di Giulio,Luigina Cellini
AIMBacterial biofilms can form on the surfaces in hospital, clinics, farms and food processing plants, representing a possible source of infections and cross-contamination. This study investigates the effectiveness of new commercial wipes against Staphylococcus aureus and Pseudomonas aeruginosa biofilms (early attachment and formed biofilms), assessing LH SALVIETTE wipes (Lombarda H S.r.l) potential for controlling biofilm formation.METHODS AND RESULTSThe wipes efficacy was studied against the early attachment phase and formed biofilm of S. aureus ATCC 6538 and P. aeruginosa ATCC 15442 on a polyvinyl chloride (PVC) surface, following a modified standard test EN 16615:2015, measuring Log10 reduction and cell viability using Live/dead staining. It was also evaluated the wipes anti-adhesive activity over time (3 h, 24 h), calculating CFU.mL-1 reduction. Data were analyzed using t-Student test. The wipes significantly reduced both early phase and formed S. aureus biofilm, preventing dispersion on PVC surfaces. Live/dead imaging showed bacterial cluster disaggregation and killing action. The bacterial adhesive capability decreased after short-time treatment (3 h) with the wipes compared to 24 h.CONCLUSIONSResults demonstrated decreased bacterial count on PVC surface both for early attachment phase and formed biofilms, also preventing the bacterial biofilm dispersion.
{"title":"New commercial wipes inhibit the dispersion and adhesion of S. aureus and P. aeruginosa biofilms.","authors":"Paola Di Fermo,Firas Diban,Elisabetta Ancarani,Kelvin Yu,Sara D'Arcangelo,Simonetta D'Ercole,Silvia Di Lodovico,Mara Di Giulio,Luigina Cellini","doi":"10.1093/jambio/lxae234","DOIUrl":"https://doi.org/10.1093/jambio/lxae234","url":null,"abstract":"AIMBacterial biofilms can form on the surfaces in hospital, clinics, farms and food processing plants, representing a possible source of infections and cross-contamination. This study investigates the effectiveness of new commercial wipes against Staphylococcus aureus and Pseudomonas aeruginosa biofilms (early attachment and formed biofilms), assessing LH SALVIETTE wipes (Lombarda H S.r.l) potential for controlling biofilm formation.METHODS AND RESULTSThe wipes efficacy was studied against the early attachment phase and formed biofilm of S. aureus ATCC 6538 and P. aeruginosa ATCC 15442 on a polyvinyl chloride (PVC) surface, following a modified standard test EN 16615:2015, measuring Log10 reduction and cell viability using Live/dead staining. It was also evaluated the wipes anti-adhesive activity over time (3 h, 24 h), calculating CFU.mL-1 reduction. Data were analyzed using t-Student test. The wipes significantly reduced both early phase and formed S. aureus biofilm, preventing dispersion on PVC surfaces. Live/dead imaging showed bacterial cluster disaggregation and killing action. The bacterial adhesive capability decreased after short-time treatment (3 h) with the wipes compared to 24 h.CONCLUSIONSResults demonstrated decreased bacterial count on PVC surface both for early attachment phase and formed biofilms, also preventing the bacterial biofilm dispersion.","PeriodicalId":15036,"journal":{"name":"Journal of Applied Microbiology","volume":"727 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142269334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
AIMSThis study aims to assess the potential bacterial inactivation pathway triggered by argon (Ar) cold atmospheric pressure plasma jet (CAPJ) discharge using spectroscopic and imaging techniques.METHODS AND RESULTSElectrical and reactive species of the Ar CAPJ discharge was characterized. The chemical composition and morphology of bacteria pre- and post-CAPJ exposure were assessed using Fourier transform infrared (FTIR), Raman micro-spectroscopy, and transmission electron microscopy (TEM). A greater than 6 log reduction of E. coli and S. aureus was achieved within 60 and 120 s of CAPJ exposure, respectively. Extremely low D- values (< 20 s) were recorded for both the isolates. The alterations in the FTIR spectra and Raman micro-spectra signals of post-CAPJ exposed bacteria revealed the degree of destruction at the molecular level, such as lipid peroxidation, protein oxidation, bond breakages, etc. Further, TEM images of exposed bacteria indicated the incurred damages on cell morphology by CAPJ reactive species. Also, the inactivation process varied for both isolates, as evidenced by the correlation between the inactivation curve and FTIR spectra. It was observed that the identified gas-phase reactive species, such as Ar I, O I, OH•, NO+, OH+, NO2-, NO3-, etc. played a significant role in bacterial inactivation.CONCLUSIONSThis study clearly demonstrated the effect of CAPJ exposure on bacterial cell morphology and molecular composition, illuminating potential bacterial inactivation mechanisms.
目的本研究旨在利用光谱和成像技术评估氩气（Ar）冷大气压等离子体射流（CAPJ）放电引发的潜在细菌灭活途径。使用傅立叶变换红外光谱（FTIR）、拉曼显微光谱和透射电子显微镜（TEM）评估了细菌在接触 CAPJ 前后的化学成分和形态。在 CAPJ 暴露 60 秒和 120 秒内，大肠杆菌和金黄色葡萄球菌分别减少了 6 个对数值以上。两种分离物的 D 值都极低（< 20 秒）。CAPJ 暴露后细菌的傅立叶变换红外光谱和拉曼微光谱信号的变化显示了分子水平的破坏程度，如脂质过氧化、蛋白质氧化、键断裂等。此外，暴露细菌的 TEM 图像显示了 CAPJ 活性物种对细胞形态造成的破坏。此外，两种分离菌的灭活过程各不相同，灭活曲线与傅立叶变换红外光谱之间的相关性也证明了这一点。据观察，已确定的气相反应物种，如 Ar I、O I、OH-、NO+、OH+、NO2-、NO3- 等在细菌灭活过程中发挥了重要作用。
{"title":"Elucidating the bacterial inactivation mechanism by argon cold atmospheric pressure plasma jet through spectroscopic and imaging techniques.","authors":"Sarthak Das,Sarita Mohapatra,Satyananda Kar","doi":"10.1093/jambio/lxae238","DOIUrl":"https://doi.org/10.1093/jambio/lxae238","url":null,"abstract":"AIMSThis study aims to assess the potential bacterial inactivation pathway triggered by argon (Ar) cold atmospheric pressure plasma jet (CAPJ) discharge using spectroscopic and imaging techniques.METHODS AND RESULTSElectrical and reactive species of the Ar CAPJ discharge was characterized. The chemical composition and morphology of bacteria pre- and post-CAPJ exposure were assessed using Fourier transform infrared (FTIR), Raman micro-spectroscopy, and transmission electron microscopy (TEM). A greater than 6 log reduction of E. coli and S. aureus was achieved within 60 and 120 s of CAPJ exposure, respectively. Extremely low D- values (< 20 s) were recorded for both the isolates. The alterations in the FTIR spectra and Raman micro-spectra signals of post-CAPJ exposed bacteria revealed the degree of destruction at the molecular level, such as lipid peroxidation, protein oxidation, bond breakages, etc. Further, TEM images of exposed bacteria indicated the incurred damages on cell morphology by CAPJ reactive species. Also, the inactivation process varied for both isolates, as evidenced by the correlation between the inactivation curve and FTIR spectra. It was observed that the identified gas-phase reactive species, such as Ar I, O I, OH•, NO+, OH+, NO2-, NO3-, etc. played a significant role in bacterial inactivation.CONCLUSIONSThis study clearly demonstrated the effect of CAPJ exposure on bacterial cell morphology and molecular composition, illuminating potential bacterial inactivation mechanisms.","PeriodicalId":15036,"journal":{"name":"Journal of Applied Microbiology","volume":"7 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142182451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
AIMSHeterologous expression of sulfur:quinone oxidoreductase (Sqr) from Halomonas mongoliensis JS01, which is responsible for oxidizing sulfide to elemental sulfur, in Thioalkalivibrio versutus (T. versutus)D301 improves desulfurization.METHODS AND RESULTSWe expressed sqr in T. versutus D301 by conjugative transfer and then assayed its desulfurization capacity in an airlift reactor and analyzed its transcriptome at -380 mV ORP. Our findings demonstrate that the D301-sqr+ strain, utilizing sodium sulfide as a sulfur source under optimal ORP conditions (-380mV), achieved an elemental sulfur yield of 95%. This represents an 8% increase over the T. versutus D301. Moreover, the sodium sulfide utilization rate for D301-sqr+ showed a marked improvement (0.741 vs. 0.651 mmol∙(L·h)-1), with a concurrent increase in the rate of elemental sulfur production when compared to the T. versutus D301 (0.716 vs. 0.518 mmol∙(L·h)-1). Transcriptome analysis revealed that the flavocytochrome c (fcc) and the sox system were differentially transcriptionally down-regulated in D301-sqr+ compared with the T. versutus D301.CONCLUSIONSHeterologous expression of the gene sqr altered the transcription of related genes in T. versutus D301 sulfur oxidation pathway, increasing the yield of elemental sulfur and the rate of sulfur oxidation, and making D301-sqr+ more potential for industrial applications.
AIMSHeterologous expression of sulfur:quinone oxidoreductase (Sqr) from Halomonas mongoliensis JS01, which is responsible to oxidizing sulfide to elemental sulfur, in Thioalkalivibrio versutus (T. versutus)D301 improves desulfurization.Method and RESULTS We expressed sqr in T. versutus D301 by conjugative transfer.方法与结果 我们通过共轭转移法在全氟弧菌 D301 中表达了 sqr，然后在空运反应器中测定了其脱硫能力，并分析了其在 -380 mV ORP 条件下的转录组。我们的研究结果表明，D301-sqr+ 菌株在最佳 ORP 条件（-380mV）下利用硫化钠作为硫源，元素硫产量达到 95%。这比 T. versutus D301 提高了 8%。此外，D301-sqr+的硫化钠利用率也有显著提高（0.741 vs. 0.651 mmol∙(L-h)-1），与T. versutus D301（0.716 vs. 0.518 mmol∙(L-h)-1）相比，元素硫的产生率也同时提高。结论异源表达 sqr 基因改变了 T. versutus D301 硫氧化途径中相关基因的转录，提高了元素硫的产量和硫氧化速率，使 D301-sqr+ 更具工业应用潜力。
{"title":"Heterologous expression of sulfur:quinone oxidoreductase (Sqr) to improve Thioalkalivibrio versutus D301 desulfurization performance.","authors":"Zhuang Tian,Chenxi Yu,He Li,Bin Song,Jianwei Lv,Chuang Liu,Wanting Sun,Xiao Hu,Yixi Xiong,Jinlong Liu,Xiyu Cheng,Maohua Yang,Jianmin Xing","doi":"10.1093/jambio/lxae237","DOIUrl":"https://doi.org/10.1093/jambio/lxae237","url":null,"abstract":"AIMSHeterologous expression of sulfur:quinone oxidoreductase (Sqr) from Halomonas mongoliensis JS01, which is responsible for oxidizing sulfide to elemental sulfur, in Thioalkalivibrio versutus (T. versutus)D301 improves desulfurization.METHODS AND RESULTSWe expressed sqr in T. versutus D301 by conjugative transfer and then assayed its desulfurization capacity in an airlift reactor and analyzed its transcriptome at -380 mV ORP. Our findings demonstrate that the D301-sqr+ strain, utilizing sodium sulfide as a sulfur source under optimal ORP conditions (-380mV), achieved an elemental sulfur yield of 95%. This represents an 8% increase over the T. versutus D301. Moreover, the sodium sulfide utilization rate for D301-sqr+ showed a marked improvement (0.741 vs. 0.651 mmol∙(L·h)-1), with a concurrent increase in the rate of elemental sulfur production when compared to the T. versutus D301 (0.716 vs. 0.518 mmol∙(L·h)-1). Transcriptome analysis revealed that the flavocytochrome c (fcc) and the sox system were differentially transcriptionally down-regulated in D301-sqr+ compared with the T. versutus D301.CONCLUSIONSHeterologous expression of the gene sqr altered the transcription of related genes in T. versutus D301 sulfur oxidation pathway, increasing the yield of elemental sulfur and the rate of sulfur oxidation, and making D301-sqr+ more potential for industrial applications.","PeriodicalId":15036,"journal":{"name":"Journal of Applied Microbiology","volume":"32 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142182467","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Agnes Nketiah,Joycelyn K Quansah,Angela Pary-Hanson Kunadu
AIMThis study reports the presence of carbapenem-resistant E. coli hybrid pathovars and its prevalence in 200 fresh-cut fruits from Accra.METHODS AND RESULTSStandard culture methods were used to quantify microbial indicators and E. coli on fresh-cut fruits retailed in formal and informal outlets in Accra. The Kirby-Bauer disc diffusion method was used to determine the antibiotic resistance profile of E. coli, while multiplex PCR was employed to identify the virulence and carbapenem resistance genes. E. coli prevalence in cut-fruits was 17%, with pawpaw, watermelon, and mix-fruit having higher prevalence than pineapple. Of the 34 E. coli isolates from fresh-cut fruits, 44% showed broad resistance to beta-lactam antibiotics, while 5.9% showed carbapenem resistance. The study identified virulence genes associated with all E. coli isolates including stx1, stx2, escV, and ipaH, of which 97% were hybrid pathovars bearing genes for STEC/EPEC/EIEC. The carbapenemase gene, blaIMP, was associated with both carbapenem-resistant E. coli phenotypes identified.CONCLUSIONDespite a low carbapenem-resistance prevalence observed among E. coli isolates, hypervirulent hybrid strains of E. coli is present in fresh-cut fruits in the sampling area, posing a potential public health risk to fresh-cut fruit consumers.
{"title":"Presence of carbapenem resistance in hybrid E. coli pathovars from ready-to-eat fresh-cut fruits in Accra, Ghana.","authors":"Agnes Nketiah,Joycelyn K Quansah,Angela Pary-Hanson Kunadu","doi":"10.1093/jambio/lxae239","DOIUrl":"https://doi.org/10.1093/jambio/lxae239","url":null,"abstract":"AIMThis study reports the presence of carbapenem-resistant E. coli hybrid pathovars and its prevalence in 200 fresh-cut fruits from Accra.METHODS AND RESULTSStandard culture methods were used to quantify microbial indicators and E. coli on fresh-cut fruits retailed in formal and informal outlets in Accra. The Kirby-Bauer disc diffusion method was used to determine the antibiotic resistance profile of E. coli, while multiplex PCR was employed to identify the virulence and carbapenem resistance genes. E. coli prevalence in cut-fruits was 17%, with pawpaw, watermelon, and mix-fruit having higher prevalence than pineapple. Of the 34 E. coli isolates from fresh-cut fruits, 44% showed broad resistance to beta-lactam antibiotics, while 5.9% showed carbapenem resistance. The study identified virulence genes associated with all E. coli isolates including stx1, stx2, escV, and ipaH, of which 97% were hybrid pathovars bearing genes for STEC/EPEC/EIEC. The carbapenemase gene, blaIMP, was associated with both carbapenem-resistant E. coli phenotypes identified.CONCLUSIONDespite a low carbapenem-resistance prevalence observed among E. coli isolates, hypervirulent hybrid strains of E. coli is present in fresh-cut fruits in the sampling area, posing a potential public health risk to fresh-cut fruit consumers.","PeriodicalId":15036,"journal":{"name":"Journal of Applied Microbiology","volume":"17 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142182452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The increasing prevalence of AmpC- and extended-spectrum β-lactamase (ESBL)- producing food pathogens is a serious public health concern. AmpC- and ESBL-producing Salmonella species pose a high risk of food contamination.AIMSThis study aimed to investigate changes in the prevalence of Salmonella among food handlers in Japan from 2006 to 2021 using 100 randomly selected isolates from 2006, 2012, 2018, and 2021 with different serotypes and antimicrobial resistance patterns.METHODS AND RESULTSThe average Salmonella isolation rate was 0.070% (19,602/27,848,713). Serotyping revealed that the most common serotypes were Enteritidis in 2006, Infantis in 2012, Agoueve/Cubana in 2018, and Schwarzengrund in 2021. Antimicrobial susceptibility testing showed that Salmonella isolates exhibited the highest resistance to streptomycin (< 40%), followed by tetracycline (< 20%-40%). Moreover, 6% of the Salmonella isolates produced cephalosporinases with the blaCMY-2, blaCTX-M-14, and blaTEM genes. The annual incidence of cephalosporin resistance has increased. Plasmid conjugation assays revealed that cephalosporin-resistant Salmonella spp. transmitted their resistance to Escherichia coli. Additionally, plasmid genome analysis showed that the insertion sequence IS26 was encoded in the upstream and downstream regions of blaCTX-M-14 and qnrS1 in the IncHI1 plasmid, which could be transmitted to other bacteria.CONCLUSIONSThe tested Salmonella isolates showed high resistance to specific antibiotics, with differences in resistance depending on the serotype. Further increase and spread of transmissible cephalosporin-resistant strains should be noted.
{"title":"Prevalence of streptomycin and tetracycline resistance and increased transmissible third-generation cephalosporin resistance in Salmonella enterica isolates derived from food handlers in Japan from 2006 to 2021.","authors":"Natsuki Ohata,Mamoru Noda,Kenji Ohta,Moritaka Hatta,Tatsuya Nakayama","doi":"10.1093/jambio/lxae236","DOIUrl":"https://doi.org/10.1093/jambio/lxae236","url":null,"abstract":"The increasing prevalence of AmpC- and extended-spectrum β-lactamase (ESBL)- producing food pathogens is a serious public health concern. AmpC- and ESBL-producing Salmonella species pose a high risk of food contamination.AIMSThis study aimed to investigate changes in the prevalence of Salmonella among food handlers in Japan from 2006 to 2021 using 100 randomly selected isolates from 2006, 2012, 2018, and 2021 with different serotypes and antimicrobial resistance patterns.METHODS AND RESULTSThe average Salmonella isolation rate was 0.070% (19,602/27,848,713). Serotyping revealed that the most common serotypes were Enteritidis in 2006, Infantis in 2012, Agoueve/Cubana in 2018, and Schwarzengrund in 2021. Antimicrobial susceptibility testing showed that Salmonella isolates exhibited the highest resistance to streptomycin (< 40%), followed by tetracycline (< 20%-40%). Moreover, 6% of the Salmonella isolates produced cephalosporinases with the blaCMY-2, blaCTX-M-14, and blaTEM genes. The annual incidence of cephalosporin resistance has increased. Plasmid conjugation assays revealed that cephalosporin-resistant Salmonella spp. transmitted their resistance to Escherichia coli. Additionally, plasmid genome analysis showed that the insertion sequence IS26 was encoded in the upstream and downstream regions of blaCTX-M-14 and qnrS1 in the IncHI1 plasmid, which could be transmitted to other bacteria.CONCLUSIONSThe tested Salmonella isolates showed high resistance to specific antibiotics, with differences in resistance depending on the serotype. Further increase and spread of transmissible cephalosporin-resistant strains should be noted.","PeriodicalId":15036,"journal":{"name":"Journal of Applied Microbiology","volume":"24 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142182470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
AIMSBiofilms are complex microbial cell aggregates that attach to different surfaces in nature, industrial environments, or hospital settings. In photovoltaic panels (PVs), biofilms are related to significant energy conversion losses. In this study, our aim was to characterize the communities of microorganisms and the genes involved in biofilm formation.METHODS AND RESULTSIn this study, biofilm samples collected from a PV system installed in southeastern Brazil were analyzed through shotgun metagenomics, and the microbial communities and genes involved in biofilm formation were investigated. A total of 2 030 different genera were identified in the samples, many of which were classified as extremophiles or producers of exopolysaccharides. Bacteria prevailed in the samples (89%), mainly the genera Mucilaginibacter, Microbacterium, Pedobacter, Massilia, and Hymenobacter. The functional annotation revealed more than 12 000 genes related to biofilm formation and stress response. Genes involved in the iron transport and synthesis of c-di-GMP and c-AMP second messengers were abundant in the samples. The pathways related to these components play a crucial role in biofilm formation and could be promising targets for preventing biofilm formation in the PV. In addition, Raman spectroscopy analysis indicated the presence of hematite, goethite, and ferrite, consistent with the mineralogical composition of the regional soil and metal-resistant bacteria.CONCLUSIONSTaken together, our findings reveal that PV biofilms are a promising source of microorganisms of industrial interest and genes of central importance in regulating biofilm formation and persistence.
{"title":"Taxonomic and functional characterization of biofilms from a photovoltaic panel reveals high genetic and metabolic complexity of the communities.","authors":"Viviane Faria Morais Jotta,Glen Jasper Yupanqui García,Paula Luize Camargos Fonseca,Angela de Mello Ferreira,Vasco Azevedo,Bertram Brenig,Aristóteles Góes-Neto,Fernanda Badotti","doi":"10.1093/jambio/lxae231","DOIUrl":"https://doi.org/10.1093/jambio/lxae231","url":null,"abstract":"AIMSBiofilms are complex microbial cell aggregates that attach to different surfaces in nature, industrial environments, or hospital settings. In photovoltaic panels (PVs), biofilms are related to significant energy conversion losses. In this study, our aim was to characterize the communities of microorganisms and the genes involved in biofilm formation.METHODS AND RESULTSIn this study, biofilm samples collected from a PV system installed in southeastern Brazil were analyzed through shotgun metagenomics, and the microbial communities and genes involved in biofilm formation were investigated. A total of 2 030 different genera were identified in the samples, many of which were classified as extremophiles or producers of exopolysaccharides. Bacteria prevailed in the samples (89%), mainly the genera Mucilaginibacter, Microbacterium, Pedobacter, Massilia, and Hymenobacter. The functional annotation revealed more than 12 000 genes related to biofilm formation and stress response. Genes involved in the iron transport and synthesis of c-di-GMP and c-AMP second messengers were abundant in the samples. The pathways related to these components play a crucial role in biofilm formation and could be promising targets for preventing biofilm formation in the PV. In addition, Raman spectroscopy analysis indicated the presence of hematite, goethite, and ferrite, consistent with the mineralogical composition of the regional soil and metal-resistant bacteria.CONCLUSIONSTaken together, our findings reveal that PV biofilms are a promising source of microorganisms of industrial interest and genes of central importance in regulating biofilm formation and persistence.","PeriodicalId":15036,"journal":{"name":"Journal of Applied Microbiology","volume":"22 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142182468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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