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BMC Genomics Oct 2020The genome of Vibrionaceae bacteria, which consists of two circular chromosomes, is replicated in a highly ordered fashion. In fast-growing bacteria, multifork...
BACKGROUND
The genome of Vibrionaceae bacteria, which consists of two circular chromosomes, is replicated in a highly ordered fashion. In fast-growing bacteria, multifork replication results in higher gene copy numbers and increased expression of genes located close to the origin of replication of Chr 1 (ori1). This is believed to be a growth optimization strategy to satisfy the high demand of essential growth factors during fast growth. The relationship between ori1-proximate growth-related genes and gene expression during fast growth has been investigated by many researchers. However, it remains unclear which other gene categories that are present close to ori1 and if expression of all ori1-proximate genes is increased during fast growth, or if expression is selectively elevated for certain gene categories.
RESULTS
We calculated the pangenome of all complete genomes from the Vibrionaceae family and mapped the four pangene categories, core, softcore, shell and cloud, to their chromosomal positions. This revealed that core and softcore genes were found heavily biased towards ori1, while shell genes were overrepresented at the opposite part of Chr 1 (i.e., close to ter1). RNA-seq of Aliivibrio salmonicida and Vibrio natriegens showed global gene expression patterns that consistently correlated with chromosomal distance to ori1. Despite a biased gene distribution pattern, all pangene categories contributed to a skewed expression pattern at fast-growing conditions, whereas at slow-growing conditions, softcore, shell and cloud genes were responsible for elevated expression.
CONCLUSION
The pangene categories were non-randomly organized on Chr 1, with an overrepresentation of core and softcore genes around ori1, and overrepresentation of shell and cloud genes around ter1. Furthermore, we mapped our gene distribution data on to the intracellular positioning of chromatin described for V. cholerae, and found that core/softcore and shell/cloud genes appear enriched at two spatially separated intracellular regions. Based on these observations, we hypothesize that there is a link between the genomic location of genes and their cellular placement.
Topics: Chromosome Mapping; Chromosomes, Bacterial; Genes, Bacterial; Vibrionaceae
PubMed: 33023476
DOI: 10.1186/s12864-020-07117-5 -
Microbiology (Reading, England) Feb 2023The mutualistic symbiosis between the Hawaiian bobtail squid and the marine bacterium is a powerful experimental system for determining how intercellular interactions... (Review)
Review
The mutualistic symbiosis between the Hawaiian bobtail squid and the marine bacterium is a powerful experimental system for determining how intercellular interactions impact animal-bacterial associations. In nature, this symbiosis features multiple strains of within each adult animal, which indicates that different strains initially colonize each squid. Various studies have demonstrated that certain strains of possess a type-VI secretion system (T6SS), which can inhibit other strains from establishing symbiosis within the same host habitat. The T6SS is a bacterial melee weapon that enables a cell to kill adjacent cells by translocating toxic effectors via a lancet-like apparatus. This review describes the progress that has been made in understanding the factors that govern the structure and expression of the T6SS in and its effect on the symbiosis.
Topics: Animals; Aliivibrio fischeri; Type VI Secretion Systems; Symbiosis; Decapodiformes; Ecosystem; Vibrio
PubMed: 36809081
DOI: 10.1099/mic.0.001302 -
Journal of Food Protection Sep 2021In the present study, we investigated the presence, seasonal distribution, and biomolecular characteristics of Vibrio parahaemolyticus and Vibrio vulnificus in samples...
Presence, Seasonal Distribution, and Biomolecular Characterization of Vibrio parahaemolyticus and Vibrio vulnificus in Shellfish Harvested and Marketed in Sardinia (Italy) between 2017 and 2018.
ABSTRACT
In the present study, we investigated the presence, seasonal distribution, and biomolecular characteristics of Vibrio parahaemolyticus and Vibrio vulnificus in samples of bivalve mollusks (Mytilus galloprovincialis, Crassostrea gigas, and Ruditapes decussatus) harvested and marketed in Sardinia (Italy) between 2017 and 2018. A total of 435 samples were submitted for qualitative determination of Vibrio spp., V. parahaemolyticus, and V. vulnificus. Potentially enteropathogenic isolates were detected with biomolecular methods. The overall prevalence of Vibrio spp. was 7.6%. The highest Vibrio prevalence was found in R. decussatus (8.3%). The prevalences of V. parahaemolyticus and V. vulnificus were 2.7 and 4.8%, respectively. Higher prevalences of V. parahaemolyticus and V. vulnificus were found in R. decussatus (4.2%) and C. gigas (6.2%), respectively. Only two pathogenic V. parahaemolyticus strains were recovered (genotypes: tdh- and trh+; tdh+ and trh-), both from M. galloprovincialis. None of the isolates were tdh+ and trh+. Pathogenic Vibrio infections are often underestimated, and human infections are increasing in Europe. European data on the true distribution of Vibrionaceae are scarce, and the results of the present study highlight the need of constant monitoring to update the distribution of pathogenic vibrios.
Topics: Animals; Humans; Italy; Mytilus; Seasons; Shellfish; Vibrio parahaemolyticus; Vibrio vulnificus
PubMed: 33956961
DOI: 10.4315/JFP-21-059 -
Journal of Aquatic Animal Health Dec 2019In this study, levels of Vibrionaceae, Staphylococcaceae, and Enterobacteriaceae were observed in seawater from juvenile green turtle Chelonia mydas rearing tanks and in...
In this study, levels of Vibrionaceae, Staphylococcaceae, and Enterobacteriaceae were observed in seawater from juvenile green turtle Chelonia mydas rearing tanks and in the incoming coastal seawater (the water supply). Bacterial loads were compared between the incoming coastal seawater and two different rearing conditions: in cement tanks at a low stocking density and in fiberglass tanks at a high stocking density. The total bacterial counts in seawater from fiberglass tanks were statistically greater than those in cement tanks. The nonlactose and lactose fermenting enterobacteria, tellurite-reducing bacteria, and total plate counts in water from all rearing containers were greater than those in coastal seaweater by a logarithmic fold change of 2--3. Differences in bacterial population structure of the incoming coastal seawater and rearing water were also addressed. The results from biochemical identification of 344 isolates revealed that the bacteria that were commonly found in water samples were Citrobacter spp., Enterobacteria spp., Edwardsiella spp., Staphylococcus spp., Staphylococcus aureus, Photobacterium spp., Vibrio alginolyticus, and Vibrio spp. Conclusively, the microbiological monitoring of rearing water provides important and essential information on the management of aquatic animal health and husbandry.
Topics: Animals; Animals, Zoo; Enterobacteriaceae; Seawater; Staphylococcaceae; Thailand; Turtles; Vibrionaceae
PubMed: 31342564
DOI: 10.1002/aah.10082 -
Systematic and Applied Microbiology Jan 2020Two novel strains C4III282 and C4III291 were isolated from seawater collected a site off the Taketomi coral reef. Phylogenetic analysis based on the 16S rRNA sequences...
Two novel strains C4III282 and C4III291 were isolated from seawater collected a site off the Taketomi coral reef. Phylogenetic analysis based on the 16S rRNA sequences revealed that the two strains belong to the genus Vibrio. MLSA using eight protein-coding genes (ftsZ, gapA, gyrB, mreB, pyrH, recA, rpoA, and topA) showed that C4III282 and C4III291 are closely related to the members of the Ponticus clade, namely Vibrio panuliri JCM 19500, Vibrio ponticus DSM 16217, and "Vibrio rhodolitus" G98. ANI and in silico DDH values with members of the Ponticus clade were 77.6-78.7% and 22.2-23.1, respectively. The name Vibrio taketomensis sp. nov. is proposed with C4III282 (CAIM 1928=DSM 106943=JCM 33434) as the type strain.
Topics: Coral Reefs; DNA, Bacterial; Genes, Bacterial; Genome, Bacterial; Japan; Nucleic Acid Hybridization; Phylogeny; RNA, Ribosomal, 16S; Seawater; Sequence Analysis, DNA; Vibrio
PubMed: 31862126
DOI: 10.1016/j.syapm.2019.126048 -
Applied and Environmental Microbiology May 2019spp. are ubiquitous marine bacteria with high metabolism flexibility and genome plasticity. Previous studies have revealed the dynamics of planktonic vibrios in...
spp. are ubiquitous marine bacteria with high metabolism flexibility and genome plasticity. Previous studies have revealed the dynamics of planktonic vibrios in relation to environmental forces, such as temperature and salinity. However, little is known about ecology in benthic environments. Here, we elucidate the abundance, diversity, and spatial distribution of spp. in sediments of the Chinese marginal seas, with a wide spatial range from north to south covering the Yellow Sea (YS), East China Sea (ECS), and South China Sea (SCS). Quantitative analysis showed that spp. were most abundant in the SCS (∼9.04 × 10 copies/g) compared to the YS (∼1.00 × 10 copies/g) and ECS (∼8.86 × 10 copies/g). community compositions derived from Illumina sequencing of -specific 16S rRNA genes varied significantly between sampling areas, which was reflected by a strong distance-decay pattern. The spatial distribution of was governed by a joint effect of spatial and environmental factors (especially temperature, salinity, and SiO), and their respective pure effects explained only a small fraction of the community variation. Moreover, we identified the most prominent operational taxonomic units (OTUs) that were partitioned in these sea areas. Whereas OTU20 and were prevalent in the YS, and , and , , and were prevalent in the ECS and SCS, respectively. Our study demonstrated clear spatial heterogeneity of spp. in sediments of the Chinese marginal seas, laying a foundation for fully understanding the marine ecology and the ecological roles of the species. is an important component of natural marine microbial populations in terms of pathogenicity and roles in carbon cycling. Compared to the marine pelagic environment, our knowledge of the diversity and distribution pattern of spp. in sediment is limited. Here, we show higher abundance in Chinese marginal seas than in other studied sediments. There was a clear spatial differentiation of abundance and community composition in different sea areas. The benthic community displayed a strong distance-decay pattern across a wide spatial range, which was formed under the combined effects of spatial and environmental factors. These results provide deep insights into the ecological dynamics of and its environmental controls, facilitating a more comprehensive understanding of the marine ecology.
Topics: Biodiversity; China; Geologic Sediments; Oceans and Seas; Vibrio
PubMed: 30877118
DOI: 10.1128/AEM.03064-18 -
Applied and Environmental Microbiology Jul 2023Oysters play an important role in coastal ecology and are a globally popular seafood source. However, their filter-feeding lifestyle enables coastal pathogens, toxins,...
Oysters play an important role in coastal ecology and are a globally popular seafood source. However, their filter-feeding lifestyle enables coastal pathogens, toxins, and pollutants to accumulate in their tissues, potentially endangering human health. While pathogen concentrations in coastal waters are often linked to environmental conditions and runoff events, these do not always correlate with pathogen concentrations in oysters. Additional factors related to the microbial ecology of pathogenic bacteria and their relationship with oyster hosts likely play a role in accumulation but are poorly understood. In this study, we investigated whether microbial communities in water and oysters were linked to accumulation of Vibrio parahaemolyticus, Vibrio vulnificus, or fecal indicator bacteria. Site-specific environmental conditions significantly influenced microbial communities and potential pathogen concentrations in water. Oyster microbial communities, however, exhibited less variability in microbial community diversity and accumulation of target bacteria overall and were less impacted by environmental differences between sites. Instead, changes in specific microbial taxa in oyster and water samples, particularly in oyster digestive glands, were linked to elevated levels of potential pathogens. For example, increased levels of V. parahaemolyticus were associated with higher relative abundances of cyanobacteria, which could represent an environmental vector for spp. transport, and with decreased relative abundance of and other key members of the oyster digestive gland microbiota. These findings suggest that host and microbial factors, in addition to environmental variables, may influence pathogen accumulation in oysters. Bacteria in the marine environment cause thousands of human illnesses annually. Bivalves are a popular seafood source and are important in coastal ecology, but their ability to concentrate pathogens from the water can cause human illness, threatening seafood safety and security. To predict and prevent disease, it is critical to understand what causes pathogenic bacteria to accumulate in bivalves. In this study, we examined how environmental factors and host and water microbial communities were linked to potential human pathogen accumulation in oysters. Oyster microbial communities were more stable than water communities, and both contained the highest concentrations of Vibrio parahaemolyticus at sites with warmer temperatures and lower salinities. High oyster V. parahaemolyticus concentrations corresponded with abundant cyanobacteria, a potential vector for transmission, and a decrease in potentially beneficial oyster microbes. Our study suggests that poorly understood factors, including host and water microbiota, likely play a role in pathogen distribution and pathogen transmission.
Topics: Animals; Humans; Water; Ostreidae; Vibrio parahaemolyticus; Vibrio vulnificus; Bivalvia; Bacteria
PubMed: 37318344
DOI: 10.1128/aem.00318-23 -
Marine Pollution Bulletin Feb 2023Human vibriosis, caused by pathogenic Vibrio spp., such as Vibrio parahaemolyticus, Vibrio cholerae and Vibrio vulnificus, has been increasing worldwide, mediated by... (Meta-Analysis)
Meta-Analysis Review
Human vibriosis, caused by pathogenic Vibrio spp., such as Vibrio parahaemolyticus, Vibrio cholerae and Vibrio vulnificus, has been increasing worldwide, mediated by increasing consumption of seafood. The present study was conducted to examine the global prevalence of V. vulnificus, V. parahaemolyticus and V. cholerae in fishes. We searched PubMed, Web of Science, Scopus, and CNKI for peer-reviewed articles and dissertations prior to December 31, 2021. A total of 24,831 articles were retrieved, and 82 articles contained 61 fish families were included. The global pooled prevalence of V. cholerae, V. parahaemolyticus and V. vulnificus in fishes was 9.56 % (95 % CI: 2.12-20.92), 24.77 % (95 % CI: 17.40-32.93) and 5.29 % (95 % CI: 0.38-13.61), respectively. Subgroup and meta-regression analyses showed that study-level covariates, including temperature, country, continent, origin and detection methods partly explained the between-study heterogeneity. These heterogeneities were underpinned by differences of the three Vibrio spp. in fishes at geographical and climatic scales. These results reveal a high global prevalence of pathogenic Vibrio spp. in fishes and highlight the need for implementation of more effective prevention and control measures to reduce food-borne infection in humans.
Topics: Animals; Humans; Public Health; Prevalence; Seafood; Vibrio; Vibrio parahaemolyticus; Vibrio cholerae; Vibrio Infections; Fishes
PubMed: 36621299
DOI: 10.1016/j.marpolbul.2022.114521 -
PloS One 2018Siderophores are small molecules synthesized and secreted by bacteria and fungi to scavenge iron. Extracellular ferri-siderohores are recognized by cognate receptors on...
Siderophores are small molecules synthesized and secreted by bacteria and fungi to scavenge iron. Extracellular ferri-siderohores are recognized by cognate receptors on the cell surface for transport over membranes. Several siderophore systems from Vibrionaceae representatives are known and well understood, e.g., the molecular structure of the siderophore, the biosynthesis gene cluster and pathway, and the gene expression pattern. Less is known about how these systems are distributed among the ~140 Vibrionaceae species, and which evolutionary processes contributed to the present-day distribution. In this work, we compiled existing knowledge on siderophore biosynthesis systems and siderophore receptors from Vibrionaceae and used phylogenetic analyses to investigate their organization, distribution, origin and evolution. Through literature searches, we identified nine different siderophore biosynthesis systems and thirteen siderophore receptors in Vibrionaceae. Homologs were identified by BLAST searches, and the results were mapped onto a Vibrionaceae phylogeny. We identified 81 biosynthetic systems distributed in 45 Vibrionaceae species and 16 unclassified Vibrionaceae strains, and 409 receptors in 89 Vibrionaceae species and 49 unclassified Vibrionaceae strains. The majority of taxa are associated with at least one type of siderophore biosynthesis system, some (e.g., aerobactin and vibrioferrin) of which are widely distributed in the family, whereas others (i.e., bisucaberin and vibriobactin) are found in one lineage. Cognate receptors are found more widespread. Phylogenetic analysis of three siderophore systems (piscibactin, vibrioferrin and aerobactin) show that their present-day distribution can be explained by an old insertion into Vibrionaceae, followed mainly by stable vertical evolution and extensive loss, and some cases of horizontal gene transfers. The present work provides an up to date overview of the distribution of siderophore-based iron acquisition systems in Vibrionaceae, and presents phylogenetic analysis of these systems. Our results suggest that the present-day distribution is a result of several evolutionary processes, such as old and new gene acquisitions, gene loss, and both vertical and horizontal gene transfers.
Topics: Database Management Systems; Phylogeny; Siderophores; Vibrionaceae
PubMed: 29444108
DOI: 10.1371/journal.pone.0191860 -
Journal of Environmental Radioactivity Jun 2016The mechanism of biological activation by beta-emitting radionuclide tritium was studied. Luminous marine bacteria were used as a bioassay to monitor the biological...
The mechanism of biological activation by beta-emitting radionuclide tritium was studied. Luminous marine bacteria were used as a bioassay to monitor the biological effect of tritium with luminescence intensity as the physiological parameter tested. Two different types of tritium sources were used: HTO molecules distributed regularly in the surrounding aqueous medium, and a solid source with tritium atoms fixed on its surface (tritium-labeled films, 0.11, 0.28, 0.91, and 2.36 MBq/cm(2)). When using the tritium-labeled films, tritium penetration into the cells was prevented. The both types of tritium sources revealed similar changes in the bacterial luminescence kinetics: a delay period followed by bioluminescence activation. No monotonic dependences of bioluminescence activation efficiency on specific radioactivities of the films were found. A 15-day exposure to tritiated water (100 MBq/L) did not reveal mutations in bacterial DNA. The results obtained give preference to a "non-genomic" mechanism of bioluminescence activation by tritium. An activation of the intracellular bioluminescence process develops without penetration of tritium atoms into the cells and can be caused by intensification of trans-membrane cellular processes stimulated by ionization and radiolysis of aqueous media.
Topics: DNA, Bacterial; Luminescence; Photobacterium; Tritium; Water Pollutants, Radioactive
PubMed: 27035890
DOI: 10.1016/j.jenvrad.2016.03.017