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Microorganisms Apr 2022species are isolated and taxonomically evaluated from a wide range of sources. While and have been implicated in human disease, the potential pathogenicity of...
species are isolated and taxonomically evaluated from a wide range of sources. While and have been implicated in human disease, the potential pathogenicity of numerous other species have not been investigated. The aims were therefore to evaluate 37 species and from environmental, food, fish, water and clinical sources for production of haemolysis, growth at 37 °C, and production of virulence enzymes. The control of these strains were investigated by determination of antimicrobial and disinfectant resistance. All the species produced α- or β-haemolysis. In terms of growth at 37 °C and production of virulence enzymes, (environmental), (food) and (natural mineral water) could be potential human pathogens. might be pathogenic to fish. Trimethoprim could be the most effective antimicrobial for the treatment of a species infection, while the disinfectants that contain poly-dimethyl ammonium chloride or benzalkonium chloride could be regarded as the most effective for decontamination of surfaces contaminated with species.
PubMed: 35630340
DOI: 10.3390/microorganisms10050895 -
International Journal of Systematic and... Sep 2021A polyphasic taxonomic study was conducted on three strains isolated from drinking water systems that had previously been deposited as species at the Spanish Type...
A polyphasic taxonomic study was conducted on three strains isolated from drinking water systems that had previously been deposited as species at the Spanish Type Culture Collection in order to complete their classification. Strains CECT 9293, CECT 9390 and CECT 9393 were isolated from sites in Barcelona, Spain, in the framework of a project aimed at generating the first MALDI-TOF database specific for bacteria present in water for human consumption. Their partial 16S rRNA sequences showed that their closest relatives among the type strains of exhibited 98 % similarity or less, supporting their taxonomic novelty. At the same time, comparison between them revealed that strains CECT 9293 and CECT 9393 could perhaps be related at the species level as they shared 99.5 % similarity. However, whole genome sequencing was performed and the subsequent calculation of relatedness indices, average nucleotide identity and estimated DNA-DNA hybridization, ruled out that possibility and confirmed instead that each of the strains should be considered a separate species in the genus . Having clarified their status, we also performed phylogenomic analyses and searched for possible environmental or non-type material sequences that could be related to any of them at the species level. In parallel, the strains were characterized phenotypically and compared to their closest relatives to determine diagnostic traits to support their formal proposal. The proposed species are sp. nov. with the type strain CECT 9293 (=LMG 32084), sp. nov. with the type strain CECT 9390 (=LMG 32085) and sp. nov. with the type strain CECT 9393 (=LMG 32086).
Topics: Bacterial Typing Techniques; Base Composition; Chryseobacterium; DNA, Bacterial; Drinking Water; Fatty Acids; Humans; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA
PubMed: 34569922
DOI: 10.1099/ijsem.0.005020 -
Frontiers in Microbiology 2022Protein-glutaminase (PG), a deamidation enzyme commercially derived from , is used to improve the solubility and other functional properties of food proteins. In this...
Protein-glutaminase (PG), a deamidation enzyme commercially derived from , is used to improve the solubility and other functional properties of food proteins. In this study, a new PG-producing strain, ZYF120413-7, was isolated from soil, and it had a high PG yield and a short culture time. It gave the maximum PG activity with 0.557 U/ml on Cbz-Gln-Gly after 12 h of culture, indicating that it was more suitable for PG production. The enzyme activity recovery and purification fold were 32.95% and 161.95-fold, respectively, with a specific activity of 27.37 U/mg. The PG was a pre-pro-protein with a 16 amino acids putative signal peptide, a pro-PG of 118 amino acids, and a mature PG of 185 amino acids. The amino acid sequence identity of PG from strain ZYF120413-7 was 74 and 45%, respectively, to that of PG from 9670 and BH-PG. The optimum reaction pH and temperature of PG was 6 and 60°C, respectively. Enzyme activity was inhibited by Cu. The optimum PG substrate was Cbz-Gln-Gly, and the and values were 1.68 mM and 1.41 μM mg protein min, respectively. Degree of deamidation (DD) of soy protein isolate (SPI) treated by purified PG was 40.75% within the first 2 h and 52.35% after 18 h. These results demonstrated that the PG from ZYF120413-7 was a promising protein-deamidating enzyme for improving the functionality of food proteins.
PubMed: 36016794
DOI: 10.3389/fmicb.2022.969445 -
Microorganisms Aug 2021Climatic factors and pathogenic fungi threaten global banana production. Moreover, bananas are being cultivated using excessive amendments of nitrogen and pesticides,... (Review)
Review
Climatic factors and pathogenic fungi threaten global banana production. Moreover, bananas are being cultivated using excessive amendments of nitrogen and pesticides, which shift the microbial diversity in plants and soil. Advances in high-throughput sequencing (HTS) technologies and culture-dependent methods have provided valuable information about microbial diversity and functionality of plant-associated endophytic communities. Under stressful (biotic or abiotic) conditions, plants can recruit sets of microorganisms to alleviate specific potentially detrimental effects, a phenomenon known as "cry for help". This mechanism is likely initiated in banana plants infected by wilt pathogen. Recently, reports demonstrated the synergistic and cumulative effects of synthetic microbial communities (SynComs) on naturally occurring plant microbiomes. Indeed, probiotic SynComs have been shown to increase plant resilience against biotic and abiotic stresses and promote growth. This review focuses on endophytic bacterial diversity and keystone taxa of banana plants. We also discuss the prospects of creating SynComs composed of endophytic bacteria that could enhance the production and sustainability of Cavendish bananas ( AAA), the fourth most important crop for maintaining global food security.
PubMed: 34576701
DOI: 10.3390/microorganisms9091805 -
Journal of Advanced Research May 2015Flavobacterial diseases in fish are caused by multiple bacterial species within the family Flavobacteriaceae and are responsible for devastating losses in wild and... (Review)
Review
Flavobacterial diseases in fish are caused by multiple bacterial species within the family Flavobacteriaceae and are responsible for devastating losses in wild and farmed fish stocks around the world. In addition to directly imposing negative economic and ecological effects, flavobacterial disease outbreaks are also notoriously difficult to prevent and control despite nearly 100 years of scientific research. The emergence of recent reports linking previously uncharacterized flavobacteria to systemic infections and mortality events in fish stocks of Europe, South America, Asia, Africa, and North America is also of major concern and has highlighted some of the difficulties surrounding the diagnosis and chemotherapeutic treatment of flavobacterial fish diseases. Herein, we provide a review of the literature that focuses on Flavobacterium and Chryseobacterium spp. and emphasizes those associated with fish.
PubMed: 26257926
DOI: 10.1016/j.jare.2014.10.009 -
ACS Chemical Biology May 2022Sulfonolipids (SoLs) are a unique class of sphingolipids featuring a sulfonate group compared to other sphingolipids. However, the biological functions and biosynthesis...
Sulfonolipids (SoLs) are a unique class of sphingolipids featuring a sulfonate group compared to other sphingolipids. However, the biological functions and biosynthesis of SoLs in human microbiota have been poorly understood. Here, we report the discovery and isolation of SoLs from a human opportunistic pathogen DSM16776. We show for the first time the pro-inflammatory activity of SoLs with mice primary macrophages. Furthermore, we used both in vivo heterologous expression and in vitro biochemical reconstitution to characterize two enzymes, cysteate synthase and cysteate fatty acyltransferase, that are specifically involved in the biosynthesis of SoLs rather than other sphingolipids. Based on these two SoL-specific enzymes, our bioinformatics analysis showed a wider distribution of SoL biosynthetic genes in microbes that had not been reported as SoL producers. We selected four of these strains and verified their cysteate synthase and cysteate fatty acyltransferase activities in SoL biosynthesis. Considering this wider distribution of SoL-specific biosynthetic enzymes in the context of SoLs' activity in mediating inflammation, a common and fundamental biological process, it may suggest a more comprehensive function of SoLs at play.
Topics: Acyltransferases; Animals; Chryseobacterium; Cysteic Acid; Lipids; Mice; Sphingolipids
PubMed: 35476918
DOI: 10.1021/acschembio.2c00141 -
Microbiology Spectrum Feb 2023Ralstonia insidiosa and Chryseobacterium gleum are bacterial species commonly found in potable water systems, and these two species contribute to the robustness of...
Ralstonia insidiosa and Chryseobacterium gleum are bacterial species commonly found in potable water systems, and these two species contribute to the robustness of biofilm formation in a model six-species community from the International Space Station (ISS) potable water system. Here, we set about characterizing the interaction between these two ISS-derived strains and examining the extent to which this interaction extends to other strains and species in these two genera. The enhanced biofilm formation between the ISS strains of and is robust to starting inoculum and temperature and occurs in some but not all tested growth media, and evidence does not support a soluble mediator or coaggregation mechanism. These findings shed light on the ISS and interaction, though such enhancement is not common between these species based on our examination of other and strains, as well as other species of and . Thus, while the findings presented here increase our understanding of the ISS potable water model system, not all our findings are broadly extrapolatable to strains found outside of the ISS. Biofilms present in drinking water systems and terminal fixtures are important for human health, pipe corrosion, and water taste. Here, we examine the enhanced biofilm of cocultures for two very common bacteria from potable water systems: Ralstonia insidiosa and Chryseobacterium gleum. While strains originally isolated on the International Space Station show enhanced dual-species biofilm formation, terrestrial strains do not show the same interaction properties. This study contributes to our understanding of these two species in both dual-culture and monoculture biofilm formation.
PubMed: 36744887
DOI: 10.1128/spectrum.04105-22 -
PloS One 2022This study explored changes in the microbial community structure during straw degradation by a microbial decomposer, M44. The microbial community succession at different...
This study explored changes in the microbial community structure during straw degradation by a microbial decomposer, M44. The microbial community succession at different degradation periods was analyzed using MiSeq high-throughput sequencing. The results showed that 14 days after inoculation, the filter paper enzyme and endoglucanase activities increased to 2.55 U·mL-1 and 2.34 U·mL-1. The xylanase, laccase, and lignin peroxidase activities rose to 9.86 U·mL-1, 132.16 U·L-1, and 85.43 U·L-1 after 28 d, which was consistent with changes in the straw degradation rate. The degradation rates of straw, lignin, cellulose, and hemicellulose were 31.43%, 13.67%, 25.04%, and 21.69%, respectively, after 28 d of fermentation at 15°C. Proteobacteria, Firmicutes, and Bacteroidetes were the main bacterial species in samples at different degradation stages. The dominant genera included Pseudomonas, Delftia, and Paenibacillus during the initial stage (1 d, 7 d) and the mid-term stage (14 d). The key functional microbes during the late stage (21 d, 28 d) were Rhizobium, Chryseobacterium, Sphingobacterium, Brevundimonas, and Devosia. Changes in the bacterial consortium structure and straw degradation characteristics during different degradation periods were clarified to provide a theoretical basis for the rational utilization of microbial decomposer M44.
Topics: Bacteria; Cellulose; Fermentation; Lignin; Microbial Consortia; Temperature
PubMed: 35802565
DOI: 10.1371/journal.pone.0270162 -
Nature Communications Sep 2023The rhizosheath, or the layer of soil closely adhering to roots, can help plants to tolerate drought under moderate soil drying conditions. Rhizosheath formation is the...
The rhizosheath, or the layer of soil closely adhering to roots, can help plants to tolerate drought under moderate soil drying conditions. Rhizosheath formation is the result of poorly understood interactions between root exudates, microbes, and soil conditions. Here, we study the roles played by the soil microbiota in rhizosheath formation in barley (a dry crop). We show that barley rhizosheath formation is greater in acid soil than in alkaline soil, and inoculation with microbiota from acid soil enhances rhizosheath formation in alkaline soil. The rhizosheath-promoting activity is associated with the presence of Flavobacteriaceae and Paenibacillaceae bacteria that express genes for biosynthesis of indole-3-acetic acid (IAA, a common auxin), as determined by metagenomics and metatranscriptomics. Two bacterial strains isolated from rhizosheath (Chryseobacterium culicis and Paenibacillus polymyxa) produce IAA and enhance barley rhizosheath formation, while their IAA-defective mutants are unable to promote rhizosheath formation. Co-inoculation with the IAA-producing strains enhances barley grain yield in field experiments through an increase in spike number. Our findings contribute to our understanding of barley rhizosheath formation, and suggest potential strategies for crop improvement.
Topics: Hordeum; Bacteria; Desiccation; Indoleacetic Acids; Soil
PubMed: 37726263
DOI: 10.1038/s41467-023-40916-4 -
Microbiology Spectrum Dec 2021Antibiotic resistance genes (ARGs) and horizontal transfer of ARGs among bacterial species in the environment can have serious clinical implications as such transfers...
Antibiotic resistance genes (ARGs) and horizontal transfer of ARGs among bacterial species in the environment can have serious clinical implications as such transfers can lead to disease outbreaks from multidrug-resistant (MDR) bacteria. Infections due to antibiotic-resistant and in intensive care units have been increasing in recent years. In this study, the multi-antibiotic-resistant strain sp. POL2 was isolated from the wastewater of a livestock farm. Whole-genome sequencing and annotation revealed that the POL2 genome encodes dozens of ARGs. The integrative and conjugative element (ICE) ICEPOL2, which encodes ARGs associated with four types of antibiotics, including carbapenem, was identified in the POL2 genome, and phylogenetic affiliation analysis suggested that ICEPOL2 evolved from related ICEs of spp. Conjugation assays verified that ICEPOL2 can horizontally transfer to species, suggesting that ICEPOL2 contributes to the dissemination of multiple ARGs among spp. and spp. Because spp. is associated with clinically significant infections and high mortality, there would be challenges to clinical treatment if these bacteria acquire ICEPOL2 with its multiple ARGs, especially the carbapenem resistance gene. Therefore, the results of this study support the need for monitoring the dissemination of this type of ICE in and strains to prevent further outbreaks of MDR bacteria. Infections with multiple antibiotic-resistant and in intensive care units have been increasing in recent years. In this study, the mobile integrative and conjugative element ICEPOL2, which was associated with the transmission of a carbapenem resistance gene, was identified in the genome of the multi-antibiotic-resistant strain sp. POL2. ICEPOL2 is closely related to the ICEs from species, and ICEPOL2 can horizontally transfer to species with the gene as the insertion site. Because species are associated with clinically significant infections and high mortality, the ability of ICEPOL2 to transfer carbapenem resistance from environmental strains of to is of clinical concern.
Topics: Anti-Bacterial Agents; Chryseobacterium; Conjugation, Genetic; Drug Resistance, Multiple, Bacterial; Flavobacteriaceae; Flavobacteriaceae Infections; Gene Transfer, Horizontal; Genome, Bacterial; Humans; Phylogeny; Wastewater
PubMed: 34937181
DOI: 10.1128/Spectrum.02005-21