Cássia Milena de Souza, Murilo Moreira Dos Santos, Luciana Furlaneto-Maia, Marcia Cristina Furlaneto
{"title":"Adhesion and biofilm formation by the opportunistic pathogen <i>Candida tropicalis</i>: what do we know?","authors":"Cássia Milena de Souza, Murilo Moreira Dos Santos, Luciana Furlaneto-Maia, Marcia Cristina Furlaneto","doi":"10.1139/cjm-2022-0195","DOIUrl":"https://doi.org/10.1139/cjm-2022-0195","url":null,"abstract":"<p><p><i>Candida tropicalis</i> is among the most important <i>Candida</i> species in terms of epidemiology, virulence and resistance. Considering the increase in <i>C. tropicalis</i> incidence and high rates of mortality associated with this species, knowledge of its adhesion and biofilm formation abilities is needed. These traits determine the persistence and survival of yeast on different indwelling medical devices and host sites. <i>C. tropicalis</i> is among the most adherent <i>Candida</i> species, and it has been described as a strong biofilm producer. Environmental factors, phenotypic switching and quorum sensing molecules can affect adhesion and biofilm growth. <i>C. tropicalis</i> can form sexual biofilms, which are promoted by mating pheromones. <i>C. tropicalis</i> biofilms are regulated by a wide and complex network of genes and signaling pathways that are currently poorly understood. Morphological studies showed improved biofilm architecture, which was related to the expression of several hypha-specific genes. Based on recent updates, research is still needed to increase our knowledge on the genetic network of adhesion and biofilm formation by <i>C. tropicalis</i>, as well as the protein diversity that mediates interactions with inert materials and biological surfaces. Here, we have reviewed the main aspects related to adhesion and biofilm formation in <i>C. tropicalis</i> and summarized current knowledge on the significance of these virulence factors in this opportunistic species.</p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9550365","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":"Robert G.E. Murray: the consummate editor.","authors":"George A O'Toole","doi":"10.1139/cjm-2023-0033","DOIUrl":"https://doi.org/10.1139/cjm-2023-0033","url":null,"abstract":"N/A.","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9381844","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}
Viridiana Alejandre-Castañeda, J Alberto Patiño-Medina, Juan Gúzman-Pérez, Marco Ivan Valle-Maldonado, Javier Villegas, Cesar R Solorio-Alvarado, León Francisco Ruiz-Herrera, Rafael Ortiz-Alvarado, Karla Macías-Sánchez, Martha Isela Ramaírez-Díaz, Victor Meza-Carmen
{"title":"Role of the nonribosomal peptide synthetase siderophore enzyme (Rfs) of <i>Mucor lusitanicus</i> in controlling the growth of fungal phytopathogens.","authors":"Viridiana Alejandre-Castañeda, J Alberto Patiño-Medina, Juan Gúzman-Pérez, Marco Ivan Valle-Maldonado, Javier Villegas, Cesar R Solorio-Alvarado, León Francisco Ruiz-Herrera, Rafael Ortiz-Alvarado, Karla Macías-Sánchez, Martha Isela Ramaírez-Díaz, Victor Meza-Carmen","doi":"10.1139/cjm-2022-0203","DOIUrl":"https://doi.org/10.1139/cjm-2022-0203","url":null,"abstract":"<p><p>Dimorphic species of <i>Mucor</i>, which are cosmopolitan fungi belonging to subphylum Mucoromycotina, are metabolically versatile. Some species of <i>Mucor</i> are sources of biotechnological products, such as biodiesel from <i>Mucor circinelloides</i> and expression of heterologous proteins from <i>Mucor lusitanicus</i>. Furthermore, <i>Mucor lusitanicus</i> has been described as a model for understanding mucormycosis infections. However, little is known regarding the relationship between <i>Mucor lusitanicus</i> and other soil inhabitants. In this study, we investigated the potential use of <i>Mucor lusitanicus</i> as a biocontrol agent against fungal phytopathogens, namely <i>Fusarium oxysporum</i> f. sp. <i>lycopersici, Fusarium solani</i>, and <i>Alternaria solani</i>, which destroy economically important crops. Results showed that aerobic cell-free supernatants of the culture broth (SS) from <i>Mucor lusitanicus</i> inhibited the growth of the fungal phytopathogens in culture, soil, and tomato fruits. The SS obtained from a strain of <i>Mucor lusitanicus</i> carrying the deletion of <i>rfs</i> gene, which encodes an enzyme involved in the synthesis of siderophore rhizoferrin, had a decreased inhibitory effect against the growth of the phytopathogens. Contrarily, this inhibitory effect was more evident with the SS from an <i>rfs</i>-overexpressing strain compared to the wild-type. This study provides a framework for the potential biotechnological use of the molecules secreted from <i>Mucor lusitanicus</i> in the biocontrol of fungal phytopathogens.</p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9382073","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}
Arshad Ali Shaikh, Joost Theo Petra Verhoeven, Rupesh Kumar Sinha, Suzanne C Dufour, Kapil Tahlan
{"title":"A direct examination of microbial specialized metabolites associated with ocean sediments from Baffin Bay and the Gulf of Maine.","authors":"Arshad Ali Shaikh, Joost Theo Petra Verhoeven, Rupesh Kumar Sinha, Suzanne C Dufour, Kapil Tahlan","doi":"10.1139/cjm-2022-0205","DOIUrl":"https://doi.org/10.1139/cjm-2022-0205","url":null,"abstract":"<p><p>Specialized metabolites produced by microorganisms found in ocean sediments display a wide range of clinically relevant bioactivities, including antimicrobial, anticancer, antiviral, and anti-inflammatory. Due to limitations in our ability to culture many benthic microorganisms under laboratory conditions, their potential to produce bioactive compounds remains underexplored. However, the advent of modern mass spectrometry technologies and data analysis methods for chemical structure prediction has aided in the discovery of such metabolites from complex mixtures. In this study, ocean sediments were collected from Baffin Bay (Canadian Arctic) and the Gulf of Maine for untargeted metabolomics using mass spectrometry. A direct examination of prepared organic extracts identified 1468 spectra, of which ∼45% could be annotated using in silico analysis methods. A comparable number of spectral features were detected in sediments collected from both locations, but 16S rRNA gene sequencing revealed a significantly more diverse bacterial community in samples from Baffin Bay. Based on spectral abundance, 12 specialized metabolites known to be associated with bacteria were selected for discussion. The application of metabolomics directly on marine sediments provides an avenue for culture-independent detection of metabolites produced under natural settings. The strategy can help prioritize samples for novel bioactive metabolite discovery using traditional workflows.</p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9381411","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":"Effects of <i>Daqu</i> properties on the microbial community and their metabolites in fermented grains in Baijiu fermentation system.","authors":"Fengjiao Mao, Jun Huang, Rongqing Zhou, Hui Qin, Suyi Zhang, Xiaobo Cai, Chuanfeng Qiu","doi":"10.1139/cjm-2022-0213","DOIUrl":"https://doi.org/10.1139/cjm-2022-0213","url":null,"abstract":"<p><p><i>Daqu</i> is the natural starter for Nong-flavor Baijiu brewing. The effects of <i>Daqu</i> properties on the microbial community succession and their metabolites in fermented grains (FG) during Baijiu brewing were determined. These results showed that the effect of <i>Daqu</i> on the bacterial communities was stronger than that of the fungal communities. Compared with the conventional <i>Daqu</i> (DZ), Taikong (TK), and Qianghua (QH), <i>Daqu</i> significantly enhanced the content of volatile metabolites (especially esters) and ethanol when they were used, respectively, for FG fermentation. In the second round of fermentation, the relative abundance of <i>Lactobacillus</i> decreased, the content of lactic acid decreased, and that of caproic acid increased. In particular, the abundance of <i>Lactobacillus</i> was also reduced by 20% in FGs of the second round when TK <i>Daqu</i> was used than that in the respective first round. Partial least squares structural equation model analysis also showed that physicochemical parameters and <i>Daqu</i> properties significantly affected FG community structure and metabolism. This study provides a theoretical basis for further study on the effect of high-quality <i>Daqu</i> on the quality of fresh Baijiu and lays an important theoretical foundation for the stabilization of the Baijiu fermentation system based on <i>Daqu</i>.</p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9238092","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":"Naming new taxa of prokaryotes in the 21st century.","authors":"Aharon Oren","doi":"10.1139/cjm-2022-0266","DOIUrl":"https://doi.org/10.1139/cjm-2022-0266","url":null,"abstract":"<p><p>The nomenclature of prokaryotes is regulated by the rules of the International Code of Nomenclature of Prokaryotes (ICNP) and is based on the Linnaean binomial system. The current rules of the Code only cover the nomenclature of the cultivated minority. Proposals to incorporate the uncultivated majority of bacteria and archaea under the rules of the Code were recently rejected by the International Committee on Systematics of Prokaryotes. The provisional rank of <i>Candidatus</i> can be used to name uncultivated prokaryotes whose names cannot be validly published under the rules of the ICNP, but their names can now be validated under the Code of Nomenclature of Prokaryotes Described from Sequence Data (the SeqCode), which was recently established to cover the nomenclature of the uncultivated majority. Metagenomics, single-cell genomics, and high-throughput cultivation techniques have led to a flood of new organisms currently waiting to be named. Automated programs such as GAN and Protologger can assist researchers in naming and describing newly discovered prokaryotes, cultivated as well as uncultivated. However, Latin and Greek skills remain indispensable for proper quality control of names that must meet the standards set by the codes of nomenclature.</p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9607512","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}
Xiaohui Niu, Qian Li, Na Luan, Jia Liu, Michael Zhang, Jun An, Zuming Li, Zhihui Bai, Ran Xia, Zhichao Wu
{"title":"<i>Lactiplantibacillus plantarum</i> BW2013 protects mucosal integrity and modulates gut microbiota of mice with colitis.","authors":"Xiaohui Niu, Qian Li, Na Luan, Jia Liu, Michael Zhang, Jun An, Zuming Li, Zhihui Bai, Ran Xia, Zhichao Wu","doi":"10.1139/cjm-2022-0092","DOIUrl":"https://doi.org/10.1139/cjm-2022-0092","url":null,"abstract":"<p><p>This study explored the effects of <i>Lactiplantibacillus plantarum</i> (previously <i>Lactobacillus plantarum</i>) BW2013 on mucosal integrity and gut microbiota of mice with dextran sulfate sodium (DSS)-induced colitis. The results show that the clinical symptoms in DSS-modelled ulcerative colitis (UC) were improved by <i>L. plantarum</i> BW2013 via decreasing disease activity index scores and suppressing inflammatory cell infiltration. Furthermore, <i>L. plantarum</i> BW2013 decreased the levels of diamine oxidase activity, myeloperoxidase, and D-lactic acid. The mRNA expression of ZO-1, occludin, and claudin-1 was upregulated by <i>L. plantarum</i> BW2013, which also increased IL-10 and reduced TNF-α, IL-1β, and IL-6 in the colon. 16S rDNA sequencing showed that <i>L. plantarum</i> BW2013 enhanced α-diversity. <i>L. plantarum</i> BW2013 upregulated significantly the abundance of unidentfied <i>Lachnospiraceae</i>, <i>Lactococcus</i>, <i>Rikenella</i>, <i>Lactobacillus</i>, and <i>Odoribacter</i>, which had an inhibitory effect on inflammation and a protective effect on the integrity of the mucosa. These results demonstrate that <i>L. plantarum</i> BW2013 alleviates DSS-modelled UC by protecting mucosal integrity and ameliorating the composition of gut microbiota.</p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9237593","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}
Grant Johnson, Branden S J Gregorchuk, Arek Zubrzycki, Kurt Patrick Kolsun, Adrienne F A Meyers, Paul A Sandstrom, Michael Glen Becker
{"title":"Clinical evaluation of the GeneXpert<sup>®</sup> Xpert<sup>®</sup> Xpress SARS-CoV-2/Flu/RSV PLUS combination test.","authors":"Grant Johnson, Branden S J Gregorchuk, Arek Zubrzycki, Kurt Patrick Kolsun, Adrienne F A Meyers, Paul A Sandstrom, Michael Glen Becker","doi":"10.1139/cjm-2022-0204","DOIUrl":"https://doi.org/10.1139/cjm-2022-0204","url":null,"abstract":"<p><p>The GeneXpert<sup>®</sup> Xpert<sup>®</sup> Xpress SARS-CoV-2/Flu/RSV PLUS combination test (PLUS assay) received Health Canada approval in January 2022. The PLUS assay is similar to the SARS-CoV-2/Flu/RSV combination test, with modifications to improve assay robustness against circulating and emerging variants. The performance characteristics of the PLUS assay were assessed at the Lakeridge Health Oshawa Hospital Centre and the National Microbiology Laboratory of Canada. The PLUS assay was directly compared to the SARS-CoV-2/Flu/RSV combination test using SARS-CoV-2 culture from five variants and remnant clinical specimens collected across the coronavirus disease 2019 pandemic. This included 50 clinical specimens negative for all pathogens, 110 clinical specimens positive for SARS-CoV-2, influenza A, influenza B, RSVA, and(or) RSVB and an additional 11 mixed samples to screen for target interactions. The PLUS assay showed a high % agreement with the widely used SARS-CoV-2/Flu/RSV combination test. Based on these findings, the PLUS assay and the Xpert SARS-CoV-2/Flu/RSV combination test results are largely consistent with no observed difference in sensitivity, specificity, or time to result when challenged with various SARS-CoV-2 variants. The reported cycle threshold (Ct) values provided by the new PLUS assay were also unchanged, with the exception of a possible 1-2 decrease reported in Ct for RSVA across a limited sample size.</p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10802480","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}
Mai Farghaly, Michael F Hynes, Mohammad Nazari, Sylvia Lee Checkley, Karen Liljebjelke
{"title":"Examination of the horizontal gene transfer dynamics of an integrative and conjugative element encoding multidrug resistance in <i>Histophilus somni</i>.","authors":"Mai Farghaly, Michael F Hynes, Mohammad Nazari, Sylvia Lee Checkley, Karen Liljebjelke","doi":"10.1139/cjm-2021-0349","DOIUrl":"https://doi.org/10.1139/cjm-2021-0349","url":null,"abstract":"<p><p>Integrative and conjugative elements (ICEs) are self-transferable mobile genetic elements that play a significant role in disseminating antimicrobial resistance between bacteria via horizontal gene transfer. A recently identified ICE in a clinical isolate of <i>Histophilus somni</i> (<i>ICEHs02</i>) is 72 914 base pairs in length and harbours seven predicted antimicrobial resistance genes conferring resistance to tetracycline (<i>tetR-tet(H)</i>), florfenicol (<i>floR</i>), sulfonamide (<i>Sul2</i>), aminoglycosides (<i>APH(3″)-Ib, APH(6)-Id, APH(3')-Ia</i>), and copper (<i>mco</i>). This study investigated <i>ICEHs02</i> host range, assessed effects of antimicrobial stressors on transfer frequency, and examined effects of <i>ICEHs02</i> acquisition on hosts. Conjugation assays examined transfer frequency of <i>ICEHs02</i> to <i>H. somni</i> and <i>Pasteurella multocida</i> strains. Polymerase chain reaction assays confirmed the presence of a circular intermediate, ICE-associated core genes, and cargo genes in recipient strains. Susceptibility testing examined <i>ICEHs02</i>-associated resistance phenotypes in recipient strains. Tetracycline and ciprofloxacin induction significantly increased the transfer rates of <i>ICEHs02</i> in vitro. The copy numbers of the circular intermediate of <i>ICEHs02</i> per chromosome exhibited significant increases of ∼37-fold after tetracycline exposure and ∼4-fold after ciprofloxacin treatment. The acquisition of <i>ICEHs02</i> reduced the relative fitness of <i>H. somni</i> transconjugants (TG) by 28% (<i>w</i> = 0.72 ± 0.04) and the relative fitness of <i>P. multocida</i> TG was decreased by 15% (<i>w</i> = 0.85 ± 0.01).</p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10811843","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":"Detection of the pathogenic fungus <i>Cordyceps farinosa</i> in the <i>Thitarodes armoricanus</i> soil-rearing environment based on nucleic acid targets.","authors":"Chaoqun Tong, Tian Li, Shisui Luo, Ruoni Chen, Shijiang Chen, Junhong Wei, Yuling Qing, Shaorong Qin, Guoqing Pan, Chunfeng Li, Zeyang Zhou","doi":"10.1139/cjm-2022-0165","DOIUrl":"https://doi.org/10.1139/cjm-2022-0165","url":null,"abstract":"<p><p><i>Cordyceps farinosa,</i> an entomopathogenic fungus, infects and leads to high mortality of <i>Thitarodes armoricanus</i> larvae, which die soon after the infection of <i>C. farinose</i>, usually before the colonization of <i>Ophiocordyceps sinensis</i> owing to competitive inhibition and fruiting body formation. Therefore, monitoring <i>C. farinosa</i> in the <i>O. sinensis</i> cultivation environment is critical for minimizing the <i>C. farinosa</i> infection-induced losses. In this study, we initially designed a PCR primer pair (Tar-1F/Tar-1R) through open reading frame prediction and homology comparison of the <i>C. farinosa</i> genome sequence. This primer pair can detect both <i>C. farinosa</i> and <i>Samsoniella hepiali</i>. To further distinguish, primers (ITS5-172/ITS4-95) were then designed to selectively amplify the large ribosomal subunit sequences in the <i>C. farinosa</i> genome. All these primers were applied in combination for detection of <i>C. farinosa</i> in soil samples. The sensitivity reached a detection limit of 1 × 10<sup>6</sup> spores/g soil. In addition, these primers can detect the presence of <i>C. farinosa</i> in dead <i>T. armoricanus</i> larval samples. This newly established rapid detection method provides important information for <i>C. farinosa</i> control during <i>O. sinensis</i> cultivation.</p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10816108","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}