{"title":"Adaptive evolution of <i>Clostridium thermocellum</i> ATCC 27405 on alternate carbon sources leads to altered fermentation profiles.","authors":"Steve R Daley, Samantha Kirby, Richard Sparling","doi":"10.1139/cjm-2024-0004","DOIUrl":"10.1139/cjm-2024-0004","url":null,"abstract":"<p><p>Consolidated bioprocessing candidate, <i>Clostridium thermocellum,</i> is a cellulose hydrolysis specialist, with the ability to ferment the released sugars to produce bioethanol. <i>C. thermocellum</i> is generally studied with model substrates Avicel and cellobiose to understand the metabolic pathway leading to ethanol. In the present study, adaptive laboratory evolution, allowing <i>C. thermocellum</i> DSM 1237 to adapt to growth on glucose, fructose, and sorbitol, with the prospect that some strains will adapt their metabolism to yield more ethanol. Adaptive growth on glucose and sorbitol resulted in an approximately 1 mM and 2 mM increase in ethanol yield per millimolar glucose equivalent, respectively, accompanied by a shift in the production of the other expected fermentation end products. The increase in ethanol yield observed for sorbitol adapted cells was due to the carbon source being more reduced compared to cellobiose. Glucose and cellobiose have similar oxidation states thus the increase in ethanol yield is due to the rerouting of electrons from other reduced metabolic products excluding H<sub>2</sub> which did not decrease in yield. There was no increase in ethanol yield observed for fructose adapted cells, but there was an unanticipated elimination of formate production, also observed in sorbitol adapted cells suggesting that fructose has regulatory implications on formate production either at the transcription or protein level.</p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":" ","pages":"370-383"},"PeriodicalIF":1.8,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141236834","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}
Sani-E-Zehra Zaidi, Rahat Zaheer, Athanasios Zovoilis, Tim A McAllister
{"title":"Enterococci as a One Health indicator of antimicrobial resistance.","authors":"Sani-E-Zehra Zaidi, Rahat Zaheer, Athanasios Zovoilis, Tim A McAllister","doi":"10.1139/cjm-2024-0024","DOIUrl":"10.1139/cjm-2024-0024","url":null,"abstract":"<p><p>The rapid increase of antimicrobial-resistant bacteria in humans and livestock is concerning. Antimicrobials are essential for the treatment of disease in modern day medicine, and their misuse in humans and food animals has contributed to an increase in the prevalence of antimicrobial-resistant bacteria. Globally, antimicrobial resistance is recognized as a One Health problem affecting humans, animals, and environment. Enterococcal species are Gram-positive bacteria that are widely distributed in nature. Their occurrence, prevalence, and persistence across the One Health continuum make them an ideal candidate to study antimicrobial resistance from a One Health perspective. The objective of this review was to summarize the role of enterococci as an indicator of antimicrobial resistance across One Health sectors. We also briefly address the prevalence of enterococci in human, animal, and environmental settings. In addition, a 16S RNA gene-based phylogenetic tree was constructed to visualize the evolutionary relationship among enterococcal species and whether they segregate based on host environment. We also review the genomic basis of antimicrobial resistance in enterococcal species across the One Health continuum.</p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":" ","pages":"303-335"},"PeriodicalIF":1.8,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140847169","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}
Jordyn S Meaney, Aakanx K Panchal, Aiden J Wilcox, George C diCenzo, Bogumil J Karas
{"title":"Identifying functional multi-host shuttle plasmids to advance synthetic biology applications in <i>Mesorhizobium</i> and <i>Bradyrhizobium</i>.","authors":"Jordyn S Meaney, Aakanx K Panchal, Aiden J Wilcox, George C diCenzo, Bogumil J Karas","doi":"10.1139/cjm-2023-0232","DOIUrl":"10.1139/cjm-2023-0232","url":null,"abstract":"<p><p>Ammonia availability has a crucial role in agriculture as it ensures healthy plant growth and increased crop yields. Since diazotrophs are the only organisms capable of reducing dinitrogen to ammonia, they have great ecological importance and potential to mitigate the environmental and economic costs of synthetic fertilizer use. Rhizobia are especially valuable being that they can engage in nitrogen-fixing symbiotic relationships with legumes, and they demonstrate great diversity and plasticity in genomic and phenotypic traits. However, few rhizobial species have sufficient genetic tractability for synthetic biology applications. This study established a basic genetic toolbox with antibiotic resistance markers, multi-host shuttle plasmids and a streamlined protocol for biparental conjugation with <i>Mesorhizobium</i> and <i>Bradyrhizobium</i> species. We identified two <i>repABC</i> origins of replication from <i>Sinorhizobium meliloti</i> (pSymB) and <i>Rhizobium etli</i> (p42d) that were stable across all three strains of interest. Furthermore, the NZP2235 genome was sequenced and phylogenetic analysis determined its reclassification to <i>Mesorhizobium huakuii</i>. These tools will enable the use of plasmid-based strategies for more advanced genetic engineering projects and ultimately contribute towards the development of more sustainable agriculture practices by means of novel nitrogen-fixing organelles, elite bioinoculants, or symbiotic association with nonlegumes.</p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":" ","pages":"336-347"},"PeriodicalIF":1.8,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140847517","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}
James C Kosmopoulos, Rebecca T Batstone-Doyle, Katy D Heath
{"title":"Co-inoculation with novel nodule-inhabiting bacteria reduces the benefits of legume-rhizobium symbiosis.","authors":"James C Kosmopoulos, Rebecca T Batstone-Doyle, Katy D Heath","doi":"10.1139/cjm-2023-0209","DOIUrl":"10.1139/cjm-2023-0209","url":null,"abstract":"<p><p>The ecologically and economically vital symbiosis between nitrogen-fixing rhizobia and leguminous plants is often thought of as a bi-partite interaction, yet studies increasingly show the prevalence of non-rhizobial endophytes (NREs) that occupy nodules alongside rhizobia. Yet, what impact these NREs have on plant or rhizobium fitness remains unclear. Here, we investigated four NRE strains found to naturally co-occupy nodules of the legume <i>Medicago truncatula</i> alongside <i>Sinorhizobium meliloti</i> in native soils. Our objectives were to (1) examine the direct and indirect effects of NREs on <i>M. truncatula</i> and <i>S. meliloti</i> fitness, and (2) determine whether NREs can re-colonize root and nodule tissues upon reinoculation. We identified one NRE strain (522) as a novel <i>Paenibacillus</i> species, another strain (717A) as a novel <i>Bacillus</i> species, and the other two (702A and 733B) as novel <i>Pseudomonas</i> species. Additionally, we found that two NREs (Bacillus 717A and Pseudomonas 733B) reduced the fitness benefits obtained from symbiosis for both partners, while the other two (522, 702A) had little effect. Lastly, we found that NREs were able to co-infect host tissues alongside <i>S. meliloti</i>. This study demonstrates that variation of NREs present in natural populations must be considered to better understand legume-rhizobium dynamics in soil communities.</p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":" ","pages":"275-288"},"PeriodicalIF":1.8,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140173779","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}
Marie-Stéphanie Fradette, Sandrinne L Bourque, Manuel J Rodriguez, Steve J Charette
{"title":"Year-round monitoring of three water sources in Québec, Canada, reveals site-specific differences in conditions for <i>Cryptosporidium</i> and <i>Giardia</i> contamination.","authors":"Marie-Stéphanie Fradette, Sandrinne L Bourque, Manuel J Rodriguez, Steve J Charette","doi":"10.1139/cjm-2023-0207","DOIUrl":"10.1139/cjm-2023-0207","url":null,"abstract":"<p><p><i>Cryptosporidium</i> and <i>Giardia</i> are protozoan parasites responsible for gastrointestinal illnesses in humans and in animal species. The main way these parasites are transmitted is by ingestion of their (oo)cysts in drinking water. Monitoring (oo)cysts in water sources is beneficial to evaluate the quality of raw water supplying treatment plants. Currently, the only standardized protocol to enumerate these parasites from water samples is United States Environmental Protection Agency (USEPA) Method 1623.1. With this method, we monitored three major water sources in Quebec over a year to assess temporal and geographical variations of these parasite (oo)cysts. These three water sources have independent watersheds despite being in the same region. We found a general pattern for <i>Giardia</i>, with high concentrations of cysts during cold and transition periods, and significantly lower concentrations during the warm period. <i>Cryptosporidium</i>'s concentration was more variable throughout the year. Statistical correlations (Pearson's correlation coefficients) were established between the concentration of each parasite and various environmental parameters. The three study sites each showed unique factors correlating with the presence of both protozoa, supporting the idea that each water source must be seen as a unique entity with its own particular characteristics and therefore, must be monitored independently. Although some environmental parameters could be interesting proxies to the parasitic load, no parameter was strongly correlated throughout the whole sampling year and none of the parameters could be used as a single proxy for all three studies sources.</p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":" ","pages":"262-274"},"PeriodicalIF":1.8,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140847462","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}
Adrián Rodriguez-Carlos, Anguita Raúl, Yolanda M Jacobo-Delgado, Carmen Judith Serrano, Alan Santos-Mena, Luis Adrian De Jesus-Gonzalez, Ester Boix, Bruno Rivas-Santiago
{"title":"Drug repositioning identifies histone deacetylase inhibitors that promote innate immunity in non-tuberculous mycobacterial infection.","authors":"Adrián Rodriguez-Carlos, Anguita Raúl, Yolanda M Jacobo-Delgado, Carmen Judith Serrano, Alan Santos-Mena, Luis Adrian De Jesus-Gonzalez, Ester Boix, Bruno Rivas-Santiago","doi":"10.1139/cjm-2023-0127","DOIUrl":"10.1139/cjm-2023-0127","url":null,"abstract":"<p><p>Non-tuberculosis infections in immunocompromised patients represent a cause for concern, given the increased risks of infection, and limited treatments available. Herein, we report that molecules for binding to the catalytic site of histone deacetylase (HDAC) inhibit its activity, thus increasing the innate immune response against environmental mycobacteria. The action of HDAC inhibitors (iHDACs) was explored in a model of type II pneumocytes and macrophages infection by <i>Mycobacterium aurum</i>. The results show that the use of 1,3-diphenylurea increases the expression of the TLR-4 in <i>M. aurum</i> infected MDMs, as well as the production of defb4, IL-1β, IL-12, and IL-6. Moreover, we observed that aminoacetanilide upregulates the expression of TLR-4 together with TLR-9, defb4, CAMP, RNase 6, RNase 7, IL-1β, IL-12, and IL-6 in T2P. Results conclude that the tested iHDACs selectively modulate the expression of cytokines and antimicrobial peptides that are associated with reduction of non-tuberculous mycobacteria infection.</p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":" ","pages":"252-261"},"PeriodicalIF":1.8,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141295591","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}
Taylor L Virgin, Prinpida Sonthiphand, Sara Coyotzi, Michael W Hall, Jason J Venkiteswaran, Richard J Elgood, Sherry L Schiff, Josh D Neufeld
{"title":"Microbial communities change along the 300 km length of the Grand River for extreme high- and low-flow regimes.","authors":"Taylor L Virgin, Prinpida Sonthiphand, Sara Coyotzi, Michael W Hall, Jason J Venkiteswaran, Richard J Elgood, Sherry L Schiff, Josh D Neufeld","doi":"10.1139/cjm-2023-0092","DOIUrl":"10.1139/cjm-2023-0092","url":null,"abstract":"<p><p>The Grand River watershed is the largest catchment in southern Ontario. The river's northern and southern sections are influenced by agriculture, whereas central regions receive wastewater effluent and urban runoff. To characterize in-river microbial communities, as they relate to spatial and environmental factors, we conducted two same-day sampling events along the entire 300 km length of the river, representing contrasting flow seasons (high flow spring melt and low flow end of summer). Through high-throughput sequencing of 16S rRNA genes, we assessed the relationship between river microbiota and spatial and physicochemical variables. Flow season had a greater impact on communities than spatial or diel effects and profiles diverged with distance between sites under both flow conditions, but low-flow profiles exhibited higher beta diversity. High-flow profiles showed greater species richness and increased presence of soil and sediment taxa, which may relate to increased input from terrestrial sources. Total suspended solids, dissolved inorganic carbon, and distance from headwaters significantly explained microbial community variation during the low-flow event, whereas conductivity, sulfate, and nitrite were significant explanatory factors for spring melt. This study establishes a baseline for the Grand River's microbial community, serving as a foundation for modeling the microbiology of anthropogenically impacted freshwater systems affected by lotic processes.</p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":" ","pages":"289-302"},"PeriodicalIF":1.8,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140920959","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":"Regulation of virulence mechanisms in plant-pathogenic <i>Streptomyces</i>.","authors":"Corrie V Vincent, Dawn R D Bignell","doi":"10.1139/cjm-2023-0171","DOIUrl":"10.1139/cjm-2023-0171","url":null,"abstract":"<p><p><i>Streptomyces</i> have a uniquely complex developmental life cycle that involves the coordination of morphological differentiation with the production of numerous bioactive specialized metabolites. The majority of <i>Streptomyces</i> spp. are soil-dwelling saprophytes, while plant pathogenicity is a rare attribute among members of this genus<i>.</i> Phytopathogenic <i>Streptomyces</i> are responsible for economically important diseases such as common scab, which affects potato and other root crops. Following the acquisition of genes encoding virulence factors, <i>Streptomyces</i> pathogens are expected to have specifically adapted their regulatory pathways to enable transition from a primarily saprophytic to a pathogenic lifestyle. Investigations of the regulation of pathogenesis have primarily focused on <i>Streptomyces scabiei</i> and the principal pathogenicity determinant thaxtomin A. The coordination of growth and thaxtomin A production in this species is controlled in a hierarchical manner by cluster-situated regulators, pleiotropic regulators, signalling and plant-derived molecules, and nutrients. Although the majority of phytopathogenic <i>Streptomyces</i> produce thaxtomins, many also produce additional virulence factors, and there are scab-causing pathogens that do not produce thaxtomins. The development of effective control strategies for common scab and other <i>Streptomyces</i> plant diseases requires a more in-depth understanding of the genetic and environmental factors that modulate the plant pathogenic lifestyle of these organisms.</p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":" ","pages":"199-212"},"PeriodicalIF":1.8,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139401998","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":"High diversity within and low but significant genetic differentiation among geographic and temporal populations of the global <i>Streptococcus pneumoniae</i>.","authors":"Jezreel Dalmieda, Megan Hitchcock, Jianping Xu","doi":"10.1139/cjm-2023-0155","DOIUrl":"10.1139/cjm-2023-0155","url":null,"abstract":"<p><p><i>Streptococcus pneumoniae</i> is the major cause of invasive pneumococcal disease. However, the global population structure remains largely unexplored. In this study, we investigated the spatial and temporal patterns of genetic variation of <i>S</i>. <i>pneumoniae</i> based on archived multilocus sequence typing data from PubMLST.org. Our analyses demonstrated both shared and unique distributions of sequence types (STs) and allele types among regional populations. Among the 17 915 global STs, 36 representing 15 263 isolates were broadly shared among all six continents, consistent with recent clonal dispersal and expansion of this pathogen. The analysis of molecular variance revealed that >96% genetic variations were found within individual regional populations. However, though low (<4%), statistically significant genetic differentiation among regional populations was observed. Comparisons between non-clone-corrected and clone-corrected datasets showed that localized clonal expansion contributed significantly to the observed genetic differentiations among regions. Temporal analyses of the isolates showed that implementation of pneumococcal conjugate vaccine impacted the distributions of STs, but the effect on population structure was relatively limited. Linkage disequilibrium analyses identified evidence for recombination in all continental populations; however, the inferred recombination was not random. We discussed the limitations and implications of our analyses to the global epidemiology and future vaccine developments for <i>S</i>. <i>pneumoniae.</i></p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":" ","pages":"226-237"},"PeriodicalIF":2.8,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139995691","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}
Sophie Boutin, Ema Lussier, Isabelle Laforest-Lapointe
{"title":"Investigating the spatiotemporal dynamics of apple tree phyllosphere bacterial and fungal communities across cultivars in orchards.","authors":"Sophie Boutin, Ema Lussier, Isabelle Laforest-Lapointe","doi":"10.1139/cjm-2023-0215","DOIUrl":"10.1139/cjm-2023-0215","url":null,"abstract":"<p><p>The phyllosphere, a reservoir of diverse microbial life associated with plant health, harbors microbial communities that are subject to various complex ecological processes acting at multiple scales. In this study, we investigated the determinants of the spatiotemporal variation in bacterial and fungal communities within the apple tree phyllosphere, employing 16S and ITS amplicon sequencing. Our research assessed the impact of key factors-plant compartment, site, time, and cultivar-on the composition and diversity of leaf and flower microbial communities. Our analyses, based on samples collected from three cultivars in three orchards in 2022, revealed that site and time are the strongest drivers of apple tree phyllosphere microbial communities. Conversely, plant compartment and cultivar exhibited minor roles in explaining community composition and diversity. Predominantly, bacterial communities comprised <i>Hymenobacter</i> (25%) and <i>Sphingomonas</i> (10%), while the most relatively abundant fungal genera included <i>Aureobasidium</i> (27%) and <i>Sporobolomyces</i> (10%). Additionally, our results show a gradual decrease in alpha-diversity throughout the growth season. These findings emphasize the necessity to consider local microbial ecology dynamics in orchards, especially as many groups worldwide aim for the development of biocontrol strategies (e.g., by manipulating plant-microbe interactions). More research is needed to improve our understanding of the determinants of time and site-specific disparities within apple tree phyllosphere microbial communities across multiple years, locations, and cultivars.</p>","PeriodicalId":9381,"journal":{"name":"Canadian journal of microbiology","volume":" ","pages":"238-251"},"PeriodicalIF":2.8,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140058680","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}