Review

Authors: Mylea A Echazarreta, Karl E Klose

spp. are highly motile Gram-negative bacteria, ubiquitously found in aquatic environments. Some s are responsible for disease and morbidity of marine invertebrates and humans, while others are studied for their symbiotic interactions. spp. are motile due to synthesis of flagella that rotate and propel the bacteria. Many spp. synthesize monotrichous polar flagella (e.g., ); however, some synthesize peritrichous or lophotrichous flagella. Flagellar-mediated motility is intimately connected to biological and cellular processes such as chemotaxis, biofilm formation, colonization, and virulence of spp. This review focuses on the polar flagellum and its regulation in regard to virulence and environmental persistence.

Topics: Flagella; Organelle Biogenesis; Vibrio

PubMed: 31119103
DOI: 10.3389/fcimb.2019.00131

Review

Authors: Dhrubajyoti Nag, Dustin A Farr, Madison G Walton...

is a large and diverse genus of bacteria, of which most are nonpathogenic species found in the aquatic environment. However, a subset of the genus includes several species that are highly pathogenic, either to humans or to aquatic animals. In recent years, , commonly known as the zebrafish, has emerged as a major animal model used for studying nearly every aspect of biology, including infectious diseases. Zebrafish are especially useful because the embryos are transparent, larvae are small and facilitate imaging studies, and numerous transgenic fish strains have been constructed. Zebrafish models for several pathogenic species have been described, and indeed a fish model is highly relevant for the study of aquatic bacterial pathogens. Here, we summarize the zebrafish models that have been used to study pathogenic species to date.

Topics: Animals; Disease Models, Animal; Humans; Vibrio; Vibrio Infections; Virulence; Zebrafish

PubMed: 32778562
DOI: 10.1128/JB.00165-20

Review

Authors: Kelly A Miller, Katharine F Tomberlin, Michelle Dziejman...

Mounting evidence suggests that Type 3 Secretion Systems (T3SS) are widespread among Vibrio species, and are present in strains isolated from diverse sources such as human clinical infections, environmental reservoirs, and diseased marine life. Experiments evaluating Vibrio parahaemolyticus and Vibrio cholerae T3SS mediated virulence suggest that Vibrio T3SS pathogenicity islands have a tripartite composition. A conserved 'core' region encodes functions essential for colonization and disease in vivo, including modulation of innate immune signaling pathways and actin dynamics, whereas regions flanking core sequences are variable among strains and encode effector proteins performing a diverse array of activities. Characterizing novel functions associated with Vibrio-specific effectors is, therefore, essential for understanding how vibrios employ T3SS mechanisms to cause disease in a broad range of hosts and how T3SS island composition potentially defines species-specific disease.

Topics: Animals; Host-Pathogen Interactions; Humans; Immune Evasion; Type III Secretion Systems; Vibrio cholerae; Vibrio parahaemolyticus; Virulence; Virulence Factors

PubMed: 30711745
DOI: 10.1016/j.mib.2018.12.001

Authors: Rosa Guzmán-Hernández, Rosa Hernández-Vélez, Áraceli Contreras-Rodríguez...

Topics: Humans; Polymerase Chain Reaction; Vibrio

PubMed: 27905630
DOI: 10.4067/S0716-10182016000400011

Review

Authors: Fabiano L Thompson, Tetsuya Iida, Jean Swings...

Vibrios are ubiquitous and abundant in the aquatic environment. A high abundance of vibrios is also detected in tissues and/or organs of various marine algae and animals, e.g., abalones, bivalves, corals, fish, shrimp, sponges, squid, and zooplankton. Vibrios harbour a wealth of diverse genomes as revealed by different genomic techniques including amplified fragment length polymorphism, multilocus sequence typing, repetetive extragenic palindrome PCR, ribotyping, and whole-genome sequencing. The 74 species of this group are distributed among four different families, i.e., Enterovibrionaceae, Photobacteriaceae, Salinivibrionaceae, and Vibrionaceae. Two new genera, i.e., Enterovibrio norvegicus and Grimontia hollisae, and 20 novel species, i.e., Enterovibrio coralii, Photobacterium eurosenbergii, V. brasiliensis, V. chagasii, V. coralliillyticus, V. crassostreae, V. fortis, V. gallicus, V. hepatarius, V. hispanicus, V. kanaloaei, V. neonatus, V. neptunius, V. pomeroyi, V. pacinii, V. rotiferianus, V. superstes, V. tasmaniensis, V. ezurae, and V. xuii, have been described in the last few years. Comparative genome analyses have already revealed a variety of genomic events, including mutations, chromosomal rearrangements, loss of genes by decay or deletion, and gene acquisitions through duplication or horizontal transfer (e.g., in the acquisition of bacteriophages, pathogenicity islands, and super-integrons), that are probably important driving forces in the evolution and speciation of vibrios. Whole-genome sequencing and comparative genomics through the application of, e.g., microarrays will facilitate the investigation of the gene repertoire at the species level. Based on such new genomic information, the taxonomy and the species concept for vibrios will be reviewed in the next years.

Topics: Animals; Bacterial Typing Techniques; Bacteriology; Biodiversity; Cholera; History, 19th Century; History, 20th Century; Humans; Phylogeny; Vibrio; Vibrio Infections; Water Microbiology

PubMed: 15353563
DOI: 10.1128/MMBR.68.3.403-431.2004

Review

Authors: Karla J F Satchell

Multifunctional-autoprocessing repeats-in-toxin (MARTX) toxins are a heterogeneous group of toxins found in a number of Vibrio species and other Gram-negative bacteria. The toxins are composed of conserved repeat regions and an autoprocessing protease domain that together function as a delivery platform for transfer of cytotoxic and cytopathic domains into target eukaryotic cell cytosol. Within the cells, the effectors can alter biological processes such as signaling or cytoskeletal structure, presumably to the benefit of the bacterium. Ten effector domains are found in the various Vibrio MARTX toxins, although any one toxin carries only two to five effector domains. The specific toxin variant expressed by a species can be modified by homologous recombination to acquire or lose effector domains, such that different strains within the same species can express distinct variants of the toxins. This review examines the conserved structural elements of the MARTX toxins and details the different toxin arrangements carried by Vibrio species and strains. The catalytic function of domains and how the toxins are linked to pathogenesis of human and animals is described.

Topics: Bacterial Toxins; Humans; Protein Structure, Tertiary; Protein Transport; Seafood; Type III Secretion Systems; Type IV Secretion Systems; Vibrio; Vibrio Infections

PubMed: 26185092
DOI: 10.1128/microbiolspec.VE-0002-2014

Review

Authors: Fitnat H Yildiz, Karen L Visick

Vibrios are natural inhabitants of aquatic environments and form symbiotic or pathogenic relationships with eukaryotic hosts. Recent studies reveal that the ability of vibrios to form biofilms (i.e. matrix-enclosed, surface-associated communities) depends upon specific structural genes (flagella, pili and exopolysaccharide biosynthesis) and regulatory processes (two-component regulators, quorum sensing and c-di-GMP signaling). Here, we compare and contrast mechanisms and regulation of biofilm formation by Vibrio species, with a focus on Vibrio cholerae, Vibrio parahaemolyticus, Vibrio vulnificus and Vibrio fischeri. Although many aspects are the same, others differ dramatically. Crucial questions that remain to be answered regarding the molecular underpinnings of Vibrio biofilm formation are also discussed.

Topics: Biofilms; Gene Expression Regulation, Bacterial; Quorum Sensing; Signal Transduction; Vibrio

PubMed: 19231189
DOI: 10.1016/j.tim.2008.12.004

Review

Authors: Alyssa S Ball, Ryan R Chaparian, Julia C van Kessel...

The coordination of group behaviors in bacteria is accomplished via the cell-cell signaling process called quorum sensing. Vibrios have historically been models for studying bacterial communication due to the diverse and remarkable behaviors controlled by quorum sensing in these bacteria, including bioluminescence, type III and type VI secretion, biofilm formation, and motility. Here, we discuss the LuxR/HapR family of proteins, the master global transcription factors that direct downstream gene expression in response to changes in cell density. These proteins are structurally similar to TetR transcription factors but exhibit distinct biochemical and genetic features from TetR that determine their regulatory influence on the quorum sensing gene network. We review here the gene groups regulated by LuxR/HapR and quorum sensing and explore the targets that are common and unique among species.

Topics: DNA, Bacterial; Dietary Carbohydrates; Gene Expression Regulation, Bacterial; Genes, Bacterial; Quorum Sensing; Repressor Proteins; Sequence Analysis, DNA; Signal Transduction; Trans-Activators; Transcription Factors; Vibrio; Vibrio cholerae

PubMed: 28484045
DOI: 10.1128/JB.00105-17

Authors: Sara Elmahdi, Salina Parveen, Sylvia Ossai...

and are naturally occurring estuarine bacteria and are the leading causes of seafood-associated infections and mortality in the United States. Though multiple-antibiotic-resistant and strains have been reported, resistance patterns in vibrios are not as well documented as those of other foodborne bacterial pathogens. Salinity relaying (SR) is a postharvest processing (PHP) treatment to reduce the abundances of these pathogens in shellfish harvested during the warmer months. The purpose of this study was to evaluate the antimicrobial susceptibility (AMS), pathogenicity, and genetic profiles of and recovered from oysters during an oyster relay study. Isolates ( [ = 296] and [ = 94]) were recovered from oysters before and during the 21-day relaying study to detect virulence genes ( and ) and genes correlated with virulence () using multiplex quantitative PCR (qPCR). AMS to 20 different antibiotics was investigated using microbroth dilution, and pulsed-field gel electrophoresis (PFGE) was used to study the genetic profiles of the isolates. Twenty percent of isolates were , while 1 and 2% of were and , respectively. More than 77% of the isolates and 30% of the isolates were resistant to at least one antimicrobial. Forty-eight percent of and 8% of isolates were resistant to two or more antimicrobials. All isolates demonstrated a high genetic diversity, even among those isolated from the same site and having a similar AMS profile. No significant effects of the relaying process on AMS, virulence genes, or PFGE profiles of and were observed. Analysis of the antibiotic resistance profiles of and isolated from oysters during this study indicated that more than 48% of isolates were resistant to two or more antimicrobials, including those recommended by the CDC for treating infections. Also, the isolates showed high MICs for some of the infection treatment antibiotics. Monitoring of AMS profiles of this bacterium is important to ensure optimal treatment of infections and improve food safety. Our study showed no significant differences in the AMS profiles of ( = 0.26) and ( = 0.23) isolated from the oysters collected before versus after relaying. This suggests that the salinity of the relaying sites did not affect the AMS profiles of the isolates, although it did reduce the numbers of these bacteria in oysters (S. Parveen et al., J Food Sci 82:484-491, 2017, https://doi.org/10.1111/1750-3841.13584).

Topics: Animals; Anti-Bacterial Agents; Bacterial Proteins; Colony Count, Microbial; Drug Resistance, Multiple, Bacterial; Food Handling; Food Safety; Genetic Variation; Microbial Sensitivity Tests; Ostreidae; Polymerase Chain Reaction; Salinity; Shellfish; Vibrio Infections; Vibrio parahaemolyticus; Vibrio vulnificus; Virulence

PubMed: 29150510
DOI: 10.1128/AEM.01790-17

Review

Authors: Colin B Munn

The tissue, skeleton, and secreted mucus of corals supports a highly dynamic and diverse community of microbes, which play a major role in the health status of corals such as the provision of essential nutrients or the metabolism of waste products. However, members of the Vibrio genus are prominent as causative agents of disease in corals. The aim of this chapter is to review our understanding of the spectrum of disease effects displayed by coral-associated vibrios, with a particular emphasis on the few species where detailed studies of pathogenicity have been conducted. The role of Vibrio shilonii in seasonal bleaching of Oculina patagonica and the development of the coral probiotic hypothesis is reviewed, pointing to unanswered questions about this phenomenon. Detailed consideration is given to studies of V. coralliilyticus and related pathogens and changes in the dominance of vibrios associated with coral bleaching. Other Vibrio-associated disease syndromes discussed include yellow band/blotch disease and tissue necrosis in temperate gorgonian corals. The review includes analysis of the role of enzymes, resistance to oxidative stress, and quorum sensing in virulence of coral-associated vibrios. The review concludes that we should probably regard most-possibly all-vibrios as "opportunistic" pathogens which, under certain environmental conditions, are capable of overwhelming the defense mechanisms of appropriate hosts, leading to rapid growth and tissue destruction.

Topics: Animals; Anthozoa; Vibrio

PubMed: 26350314
DOI: 10.1128/microbiolspec.VE-0006-2014