scholarly journals Community Change and Pathogenicity of Vibrio

2021 ◽  
Author(s):  
Lixing Huang ◽  
Qiancheng Gao ◽  
Youyu Zhang ◽  
Wei Xu ◽  
Qingpi Yan
Keyword(s):  
Virulence Factors ◽  
Pathogenic Bacteria ◽  
Virulence Genes ◽  
Vibrio Vulnificus ◽  
Abiotic Factors ◽  
Seawater Temperature ◽  
Aquatic Animal ◽  
Pathogenic Vibrio ◽  
Vibrio Infection ◽  
Community Changes

Vibrio is a rod-shaped Gram-negative bacteria, which is widely distributed in marine and estuarine environments worldwide. It is an important component of the aquatic ecosystem and plays an important role in biogeochemical cycle. Its population dynamics are usually affected by climate and seasonal factors. Most of the Vibrios in the environment are not pathogenic, but some of them are pathogenic bacteria for human and animal, such as Vibrio cholerae, Vibrio vulnificus, Vibrio parahaemolyticus, and Vibrio anguillarum, etc., which are generally reported to be related to aquatic animal diseases and human food-borne diseases. Over the last couple of years, due to the influence of the rising seawater temperature and climate change, the incidence of diseases caused by Vibrio infection has increased significantly, which poses a great threat to human health and aquaculture. The research on pathogenic Vibrio has attracted more and more attention. The abundance and community changes of Vibrio in the environment are usually controlled by many biological and abiotic factors. The Vibrio pathogenicity is related to the virulence factors encoded by virulence genes. The process of Vibrio infecting the host and causing host disease is determined by multiple virulence factors acting together, instead of being determined by a single virulence factor. In this chapter, community changes of Vibrio, as well as the virulence factors of Vibrio and the related virulence genes of Vibiro are summarized, and their important roles in Vibrio infection are also discussed.

scholarly journals Whole Genome Sequence Analysis of Brucella melitensis Phylogeny and Virulence Factors

2021 ◽  
Vol 12 (3) ◽  
pp. 698-710
Author(s):  
Peter Rabinowitz ◽  
Bar Zilberman ◽  
Yair Motro ◽  
Marilyn C. Roberts ◽  
Alex Greninger ◽  
...  
Keyword(s):  
Virulence Factors ◽  
Pathogenic Bacteria ◽  
Virulence Genes ◽  
Brucella Melitensis ◽  
Geographic Region ◽  
Clinical Severity ◽  
Whole Genome Sequence ◽  
Whole Genome ◽  
Pan Genome ◽  
Wide Range

Brucellosis has a wide range of clinical severity in humans that remains poorly understood. Whole genome sequencing (WGS) analysis may be able to detect variation in virulence genes. We used Brucella melitensis sequences in the NCBI Sequence Read Archive (SRA) database to assemble 248 whole genomes, and additionally, assembled 27 B. melitensis genomes from samples of human patients in Southern Israel. We searched the 275 assembled genomes for the 43 B. melitensis virulence genes in the Virulence Factors of Pathogenic Bacteria Database (VFDB) and 10 other published putative virulence genes. We explored pan-genome variation across the genomes and in a pilot analysis, explored single nucleotide polymorphism (SNP) variation among the ten putative virulence genes. More than 99% of the genomes had sequences for all Brucella melitensis virulence genes included in the VFDB. The 10 other virulence genes of interest were present across all the genomes, but three of these genes had SNP variation associated with particular Brucella melitensis genotypes. SNP variation was also seen within the Israeli genomes obtained from a small geographic region. While the Brucella genome is highly conserved, this novel and large whole genome study of Brucella demonstrates the ability of whole genome and pan-genome analysis to screen multiple genomes and identify SNP variation in both known and novel virulence genes that could be associated with differential disease virulence. Further development of whole genome techniques and linkage with clinical metadata on disease outcomes could shed light on whether such variation in the Brucella genome plays a role in pathogenesis.

scholarly journals Characterization and Pathogenic Significance of Vibrio vulnificus Antigens Preferentially Expressed in Septicemic Patients

2003 ◽  
Vol 71 (10) ◽  
pp. 5461-5471 ◽  
Author(s):  
Young Ran Kim ◽  
Shee Eun Lee ◽  
Choon Mee Kim ◽  
Soo Young Kim ◽  
Eun Kyoung Shin ◽  
...  
Keyword(s):  
Dna Sequences ◽  
Transcriptional Activation ◽  
Pathogenic Bacteria ◽  
Virulence Genes ◽  
Vibrio Vulnificus ◽  
Lethal Dose ◽  
Hypothetical Protein ◽  
Expression Library

ABSTRACT Many important virulence genes of pathogenic bacteria are preferentially expressed in vivo. We used the recently developed in vivo-induced antigen technology (IVIAT) to identify Vibrio vulnificus genes induced in vivo. An expression library of V. vulnificus was screened by colony blot analysis by using pooled convalescent-phase serum that had been thoroughly adsorbed with in vitro-expressed V. vulnificus whole cells and lysates. Twelve clones were selected, and the sequences of the insert DNAs were analyzed. The DNA sequences showed homologies with genes encoding proteins of diverse functions: these functions included chemotaxis (a methyl-accepting chemotaxis protein), signaling (a GGDEF-containing protein and a putative serine/threonine kinase), biosynthesis and metabolism (PyrH, PurH, and IlvC), secretion (TatB and plasmid Achromobacter secretion [PAS] factor), transcriptional activation (IlvY and HlyU), and the activity of a putative lipoprotein (YaeC). In addition, one identified open reading frame encoded a hypothetical protein. Isogenic mutants of the 12 in vivo-expressed (ive) genes were constructed and tested for cytotoxicity. Cytotoxic activity of the mutant strains, as measured by lactate dehydrogenase release from HeLa cells, was nearly abolished in pyrH, purH, and hlyU mutants. The intraperitoneal 50% lethal dose in mice increased by ca. 10- to 50-fold in these three mutants. PyrH and PurH seem to be essential for in vivo growth. HlyU appears to be one of the master regulators of in vivo virulence expression. The successful identification of ive genes responsible for the in vivo bacterial virulence, as done in the present study, demonstrates the usefulness of IVIAT for the detection of new virulence genes.

scholarly journals Seasonal and Geographical Differences in Total and Pathogenic Vibrio parahaemolyticus and Vibrio vulnificus Levels in Seawater and Oysters from the Delaware and Chesapeake Bays Determined Using Several Methods

2020 ◽  
Vol 86 (23) ◽  
Author(s):  
Salina Parveen ◽  
John Jacobs ◽  
Gulnihal Ozbay ◽  
Lathadevi K. Chintapenta ◽  
Esam Almuhaideb ◽  
...  
Keyword(s):  
Chesapeake Bay ◽  
Vibrio Parahaemolyticus ◽  
Vibrio Vulnificus ◽  
Seawater Temperature ◽  
False Negative ◽  
Delaware Bay ◽  
Most Probable Number ◽  
Probable Number ◽  
Content Type ◽  
Pathogenic Vibrio

ABSTRACT Oyster and seawater samples were collected from five sites in the Chesapeake Bay, MD, and three sites in the Delaware Bay, DE, from May to October 2016 and 2017. Abundances and detection frequencies for total and pathogenic Vibrio parahaemolyticus and Vibrio vulnificus were compared using the standard most-probable-number–PCR (MPN-PCR) assay and a direct-plating (DP) method on CHROMagar Vibrio for total (tlh+) and pathogenic (tdh+ and trh+) V. parahaemolyticus genes and total (vvhA) and pathogenic (vcgC) V. vulnificus genes. The colony overlay procedure for peptidases (COPP) assay was evaluated for total Vibrionaceae. DP had high false-negative rates (14 to 77%) for most PCR targets and was deemed unsatisfactory. Logistic regression models of the COPP assay showed high concordances with MPN-PCR for tdh+ and trh+ V. parahaemolyticus and vvhA+ V. vulnificus in oysters (85.7 to 90.9%) and seawater (81.1 to 92.7%) when seawater temperature and salinity were factored into the model, suggesting that the COPP assay could potentially serve as a more rapid method to detect vibrios in oysters and seawater. Differences in total Vibrionaceae and pathogenic Vibrio abundances between state sampling sites over different collection years were contrasted for oysters and seawater by MPN-PCR. Abundances of tdh+ and trh+ V. parahaemolyticus were ∼8-fold higher in Delaware oysters than in Maryland oysters, whereas abundances of vcgC+ V. vulnificus were nearly identical. For Delaware oysters, 93.5% were both tdh+ and trh+, compared to only 19.2% in Maryland. These results indicate that pathogenic V. parahaemolyticus was more prevalent in the Delaware Bay than in the Chesapeake Bay. IMPORTANCE While V. parahaemolyticus and V. vulnificus cause shellfish-associated morbidity and mortality among shellfish consumers, current regulatory assays for vibrios are complex, time-consuming, labor-intensive, and relatively expensive. In this study, the rapid, simple, and inexpensive COPP assay was identified as a possible alternative to MPN-PCR for shellfish monitoring. This paper shows differences in total Vibrionaceae and pathogenic vibrios found in seawater and oysters from the commercially important Delaware and Chesapeake Bays. Vibrio parahaemolyticus isolates from the Delaware Bay were more likely to contain commonly recognized pathogenicity genes than those from the Chesapeake Bay.

scholarly journals Positive Regulation of fur Gene Expression via Direct Interaction of Fur in a Pathogenic Bacterium, Vibrio vulnificus

2007 ◽  
Vol 189 (7) ◽  
pp. 2629-2636 ◽  
Author(s):  
Hyun-Jung Lee ◽  
So Hyun Bang ◽  
Kyu-Ho Lee ◽  
Soon-Jung Park
Keyword(s):  
Gene Expression ◽  
Pathogenic Bacteria ◽  
Vibrio Vulnificus ◽  
Iron Concentration ◽  
Direct Interaction ◽  
Repeated Sequence ◽  
Upstream Region ◽  
Fur Protein

ABSTRACT In pathogenic bacteria, the ability to acquire iron, which is mainly regulated by the ferric uptake regulator (Fur), is essential to maintain growth as well as its virulence. In Vibrio vulnificus, a human pathogen causing gastroenteritis and septicemia, fur gene expression is positively regulated by Fur when the iron concentration is limited (H.-J. Lee et al., J. Bacteriol. 185:5891-5896, 2003). Footprinting analysis revealed that an upstream region of the fur gene was protected by the Fur protein from DNase I under iron-depleted conditions. The protected region, from −142 to −106 relative to the transcription start site of the fur gene, contains distinct AT-rich repeats. Mutagenesis of this repeated sequence resulted in abolishment of binding by Fur. To confirm the role of this cis-acting element in Fur-mediated control of its own gene in vivo, fur expression was monitored in V. vulnificus strains using a transcriptional fusion containing the mutagenized Fur-binding site (fur mt::luxAB). Expression of fur mt::luxAB showed that it was not regulated by Fur and was not influenced by iron concentration. Therefore, this study demonstrates that V. vulnificus Fur acts as a positive regulator under iron-limited conditions by direct interaction with the fur upstream region.

scholarly journals Molecular characterization of virulence factors in Staphylococcus aureus isolated from bovine subclinical mastitis in central Ethiopia

2021 ◽  
Vol 71 (1) ◽  
Author(s):  
Desiye Tesfaye Tegegne ◽  
Gezahegne Mamo ◽  
Hika Waktole ◽  
Yohannes Equar Messele
Keyword(s):  
Staphylococcus Aureus ◽  
Dairy Cows ◽  
Virulence Factors ◽  
Virulence Genes ◽  
Animal Health ◽  
Subclinical Mastitis ◽  
Biochemical Tests ◽  
Milk Samples ◽  
Lactating Dairy Cows ◽  
Genomic Study

Abstract Purpose Staphylococcus aureus (S. aureus) is the most important pathogen involved in bovine mastitis in dairy production. S. aureus produces a spectrum of extracellular protein toxins and virulence factors which are thought to contribute to the pathogenicity of the organism. The aim of this work was to isolate and molecular characterize S. aureus associated with bovine subclinical mastitis in the central part of Ethiopia. Methods A total of 265 lactating dairy cows from various dairy farms in four different geographical locations were screened by the California mastitis test (CMT) for bovine subclinical mastitis. One hundred thirty CMT-positive milk samples were collected and transported to the laboratory. Different biochemical tests and polymerase chain reaction (PCR) were used for the identification of S. aureus isolates. Finally, PCR was performed for molecular detection of virulence genes. Results From a total of 265 lactating dairy cows screened, 49% (n = 130) were positive for bovine subclinical mastitis. One hundred thirty mastitic milk samples were subjected to bacterial culturing, and one hundred (76%) S. aureus isolates were identified based on phenotypic characters. Sixty-eight confirmed S. aureus isolates were obtained using PCR. The confirmed S. aureus isolates were tested for six virulence genes (tsst-1, hlb, eta, sea, clfA, and icaD) using PCR. Of the six virulence genes screened from all the isolates, only two (clfA and eta) were detected in the isolates. Out of 68 isolates, 25% and 22% were possessed the eta and clfA genes, respectively. Conclusion The presence of Staphylococcus aureus having virulence genes (eta and clfA) revealed that mastitis is a major concern nowadays affecting animal health, milk quality, and yield. Further genomic study of these isolates will provide broad new insights on virulence.

Evidence for Association of Vibrio Echinoideorum with Tissue Necrosis on Body Shell of the Green Sea Urchin Strongylocentrotus Droebachiensis

2021 ◽  
Author(s):  
Jonathan Hira ◽  
Klara Stensvåg
Keyword(s):  
Sea Urchin ◽  
Virulence Genes ◽  
Vibrio Vulnificus ◽  
Sea Urchins ◽  
Opportunistic Pathogen ◽  
Significant Degree ◽  
Strongylocentrotus Droebachiensis ◽  
Host Immune System ◽  
Progressive Development ◽  
Green Sea Urchin

Abstract “Sea urchin lesion syndrome” is known as sea urchins disease with the progressive development of necrotic epidermal tissue and loss of external organs, including appendages on the outer body surface. Recently, a novel strain, Vibrio echinoideorum has been isolated from the lesions of green sea urchin (Strongylocentrotus droebachiensis), an economically important mariculture species in Norway. V. echinoideorum has not been reported elsewhere in association of with green sea urchin lesion syndrome. Therefore, in this study, an immersion based bacterial challenge experiment was performed to expose sea urchins (wounded and non-wounded) to V. echinoideorum, thereby mimicking a nearly natural host-pathogen interaction under controlled conditions. This infection experiment demonstrated that only the injured sea urchins developed the lesion to a significant degree when exposed to V. echinoideorum. Pure cultures of the employed bacterial strain was recovered from the infected animals and its identity was confirmed by the MALDI-TOF MS spectra profiling. Additionally, the hemolytic phenotype of V. echinoideorum substantiated its virulence potential towards the host, and this was also supported by the cytolytic effect on red spherule cells of sea urchins. Furthermore, the genome sequence of V. echinoideorum was assumed to encode potential virulence genes and were subjected for in silico comparison with the established virulence factors of Vibrio vulnificus and Vibrio tasmaniensis. This comparative virulence profile provided novel insights about virulence genes and their putative functions related to chemotaxis, adherence, invasion, evasion of the host immune system, and damage of host tissue and cells. Thus, it supports the pathogenicity of V. echinoideorum. In conclusion, the interaction of V. echinoideorum with injured sea urchins appears to be essential for the development of lesion syndrome and therefore, revealing its potentiality as an opportunistic pathogen.

scholarly journals A silkworm infection model to investigate Vibrio vulnificus virulence genes

2016 ◽  
Vol 14 (5) ◽  
pp. 4243-4247 ◽  
Author(s):  
Mai Yamamoto ◽  
Takashige Kashimoto ◽  
Yukihiro Yoshimura ◽  
Nao Tachibana ◽  
Shiho Kuroda ◽  
...  
Keyword(s):  
Virulence Genes ◽  
Vibrio Vulnificus ◽  
Infection Model

scholarly journals Complete Genome Sequence of the Pathogenic Vibrio vulnificus Type Strain ATCC 27562

2017 ◽  
Vol 5 (35) ◽  
Author(s):  
Douglas B. Rusch ◽  
Dean A. Rowe-Magnus
Keyword(s):  
Genome Sequence ◽  
Complete Genome Sequence ◽  
Complete Genome ◽  
Type Strain ◽  
Vibrio Vulnificus ◽  
Foodborne Pathogen ◽  
The United States ◽  
Environmental Isolates ◽  
Content Type ◽  
Pathogenic Vibrio

ABSTRACT Vibrio vulnificus has the highest death rate and economic burden per case of any foodborne pathogen in the United States. A complete genome sequence of the type strain promotes comparative analyses with other clinical and environmental isolates, improving our understanding of this important human pathogen and successful environmental organism.

scholarly journals Isolation and selection of bacteria against shrimp pathogenic Vibrio parahaemolyticus from shrimp pond water on Duyen Hai district, Tra Vinh province

2020 ◽  
Vol 10 (1) ◽  
pp. 43-52
Author(s):  
Tran Vu Phuong ◽  
Dang Thi Ngoc Thanh ◽  
Cao Ngoc Diep
Keyword(s):  
Vibrio Parahaemolyticus ◽  
Pathogenic Bacteria ◽  
Pond Water ◽  
Shrimp Farming ◽  
Diffusion Method ◽  
Resistant Bacteria ◽  
Bacterial Strains ◽  
Shrimp Pond ◽  
Pathogenic Vibrio ◽  
The Status

Antibiotic has frequently been used in the shrimp-farming process in Vietnam. This leads to the status that antibiotic-resistant bacteria and products do not receive in the market. Bacteria had the resistant ability to pathogenic bacteria in water, and they have an important role in sustainable aquaculture. This study aimed to isolate and select good bacterial strains against Vibrio parahaemolyticus, pathogenic bacteria, on shrimp from 8 samples of shrimp pond water at 3 villages Ngu Lac, Phuoc An and Long Toan of Duyen Hai district, Tra Vinh province on NB agar medium. As a result, fifty-nine bacterial isolates were isolated and 10/59 isolates (16.95%) were identified as resistant to Vibrio parahaemolyticus by the well diffusion method. In 10 isolates, there were 7 isolates had good resistance to select for PCR technique and sequencing. The result indicated that these seven strains, including DH1m, DH2f, DH4d, DH8i, DH8m, DH8n, belonged to Bacilli and DH1n strain belonged to Streptomyces sp.

scholarly journals Autotransporter secretion exploits the bacterial actin-homologue

2018 ◽  
Author(s):  
Mahmoud M. Ashawesh ◽  
Robert Markus ◽  
Christopher N. Penfold ◽  
Kim R. Hardie
Keyword(s):  
Bacterial Infection ◽  
Virulence Factors ◽  
Pathogenic Bacteria ◽  
Super Resolution ◽  
Resistance Mechanisms ◽  
Dynamic Interaction ◽  
Bacterial Toxins ◽  
Gram Negative ◽  
Bacterial Cytoskeleton ◽  
Development Of Resistance

AbstractBacterial infection of humans, animals and plants relies heavily on secreted proteases that degrade host defences or activate bacterial toxins. The largest family of proteins secreted by Gram-negative pathogenic bacteria, the Autotransporters (ATs), includes key proteolytic virulence factors. There remains uncertainty about the mechanistic steps of the pathway ATs share to exit bacteria, and how it is energetically driven. This study set out to shed light on the AT secretion pathway with the ultimate aim of uncovering novel antimicrobial targets that would be unlikely to trigger the development of resistance mechanisms in bacteria. To do this, two AT virulence factors with distinct proteolytic functions, EspC (secreted from EnteropathogenicEscherichia coli) and AaaA (tethered to the extracellular surface ofPseudomonas aeruginosa) were chosen. EspC and AaaA were fluorescently labelled using two separate methods to establish the localization patterns of ATs as they are secreted from a bacterial cell. Super resolution microscopy revealed that localization of ATs occurs via a helical route along the bacterial cytoskeleton. In addition to requiring the conserved C-terminal β-barrel translocator domain of the AT, we present the first evidence that secretion is dependent on a dynamic interaction with a structure reliant upon the actin homologue MreB and the Sec translocon. These findings provide a step forward in the mechanistic understanding of the secretion of this widely distributed family of proteins that have pivotal roles in bacterial pathogenesis and conserved structural properties that could serve as novel broad-range antimicrobial targets.SignificanceSecreted bacterial proteases facilitate the infection of human, animal and plant hosts by degrading host defences or activating bacterial toxins. The autotransporter family is the largest family of proteins secreted from Gram-negative bacteria, and includes proteolytic virulence factors crucial to bacterial infection. Precisely how autotransporters migrate from the inside to the outside of the cell, and how this movement is energetically driven is a mystery. We demonstrate a spiral pathway of autotransporter secretion, presenting evidence that it involves a dynamic interaction with the actin homologue MreB that comprises the bacterial cytoskeleton. Our findings open the way to unravelling the mechanism of autotransporter secretion and offer the possibility to identify novel antimicrobial targets unlikely to trigger the development of antimicrobial resistance.

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