A5071897468- Vibrio bacteria research studies
- Escherichia coli research studies
- Aquaculture disease management and microbiota
- Salmonella and Campylobacter epidemiology
- Yersinia bacterium, plague, ectoparasites research
- Child Nutrition and Water Access
- Viral gastroenteritis research and epidemiology
- Antibiotic Resistance in Bacteria
- Clostridium difficile and Clostridium perfringens research
- Antimicrobial Resistance in Staphylococcus
- Bacterial biofilms and quorum sensing
- Antimicrobial Peptides and Activities
- Probiotics and Fermented Foods
- Brucella: diagnosis, epidemiology, treatment
- Cassava research and cyanide
- Toxin Mechanisms and Immunotoxins
- Phagocytosis and Immune Regulation
- Gut microbiota and health
- Bacteriophages and microbial interactions
Nagasaki University
2021-2025
University of California, Davis
2014-2021
Osaka University
2008-2019
Center for Genomic Science
2008
ABSTRACT Vibrio parahaemolyticus , one of the human-pathogenic vibrios, causes three major types clinical illness: gastroenteritis, wound infections, and septicemia. Thermostable direct hemolysin (TDH) secreted by this bacterium has been considered a virulence factor gastroenteritis because it biological activities, including cytotoxic enterotoxic activities. Previous reports revealed that V. strain RIMD2210633, which contains tdh two sets type III secretion system (T3SS) genes on...
Vibrio parahaemolyticus is a bacterial pathogen causative of food-borne gastroenteritis. Whole-genome sequencing V. strain RIMD2210633, which exhibits Kanagawa phenomenon (KP), revealed the presence two sets genes for type III secretion system (T3SS) on chromosomes 1 and 2, T3SS1 T3SS2, respectively. Although T3SS2 RIMD2210633 thought to be involved in human pathogenicity, i.e., enterotoxicity, have not been found trh-positive (KP-negative) strains, are also pathogenic humans. In study...
Vibrio parahaemolyticus, a bacterial pathogen, causes human gastroenteritis. A type III secretion system (T3SS2) encoded in pathogenicity island (Vp-PAI) is the main contributor to enterotoxicity and expression of Vp-PAI genes regulated by two transcriptional regulators, VtrA VtrB. However, host-derived inducer for has not been identified. Here, we demonstrate that bile induces production T3SS2-related proteins under osmotic conditions equivalent those intestinal lumen. We also show...
Changes in the microbiota composition are associated with many human diseases, but factors that govern strain abundance remain poorly defined. We show a commensal Escherichia coli and pathogenic Salmonella enterica serovar Typhimurium isolate both utilize nitrate for intestinal growth, each accesses this resource distinct biogeographical niche. Commensal E. utilizes epithelial-derived nitrate, whereas niche occupied by S. is derived from phagocytic infiltrates. Surprisingly, avirulent was...
ABSTRACT Clostridium perfringens is a causative agent of food-borne gastroenteritis for which C. enterotoxin (CPE) has been considered an essential factor. Recently, we experienced two outbreaks in non-CPE producers were strongly suspected to be the cause. Here, report novel produced by isolates, BEC (binary ). Culture supernatants strains showed fluid-accumulating activity rabbit ileal loop and suckling mouse assays. Purification enterotoxic substance high-throughput sequencing genomic DNA...
Vibrio parahaemolyticus is an important pathogen causing food-borne disease worldwide. An 80-kb pathogenicity island (Vp-PAI), which contains two tdh (thermostable direct hemolysin) genes and a set of for the type III secretion system (T3SS2), closely related to this bacterium. However, regulatory mechanisms Vp-PAI's gene expression are poorly understood. Here we report that novel ToxR-like transcriptional proteins (VtrA VtrB) regulate encoded within Vp-PAI region, including those TDH...
Typhoid fever caused by Salmonella enterica serovar (S.) Typhi differs in its clinical presentation from gastroenteritis S. Typhimurium and other non-typhoidal serovars. The different presentations are attributed part to the virulence-associated capsular polysaccharide (Vi antigen) of Typhi, which prevents phagocytes triggering a respiratory burst preventing antibody-mediated complement activation. Paradoxically, Vi antigen is absent Paratyphi A, causes disease that indistinguishable typhoid...
ABSTRACT The type III secretion system (T3SS) translocon complex is composed of several associated proteins, which form a translocation channel through the host cell plasma membrane. These proteins are key molecules that involved in pathogenicity many T3SS-positive bacteria, because they necessary to deliver effector into cells. A T3SS designated T3SS2 Vibrio parahaemolyticus thought be related enterotoxicity this bacterium humans, but mechanism unclear there only one gene (the VPA1362 gene)...
Vibrio parahaemolyticus is a Gram-negative marine bacterium that causes acute gastroenteritis in humans. The virulence of V. dependent upon type III secretion system (T3SS2). One effector for T3SS2, VopC, homologue the catalytic domain cytotoxic necrotizing factor (CNF), and was recently reported to be Rho family GTPase activator linked internalization by non-phagocytic cultured cells. Here, we provide direct evidence VopC deamidates Rac1 CDC42, but not RhoA, vivo. Our results alsosuggest...
Intracellular pathogens commonly reside within macrophages to find shelter from humoral defenses, but host cell death can expose them the extracellular milieu. We intracellular solve this dilemma by using virulence factors generate a complement-dependent find-me signal that initiates uptake new phagocyte through efferocytosis. During macrophage death, Salmonella uses type III secretion system perforate membrane of pathogen-containing vacuole (PCV), thereby triggering complement deposition on...
Capsular polysaccharides are common virulence factors of extracellular, but not intracellular bacterial pathogens, due to the antiphagocytic properties these surface structures. It is therefore paradoxical that Salmonella enterica subspecies serovar Typhi, an pathogen, synthesizes a virulence-associated (Vi) capsule, which exhibits properties. Here, we show Vi capsular polysaccharide has different functions when S. Typhi interacts with distinct subsets host phagocytes. The allowed...
In 2013, foodborne outbreaks in Japan were linked to non-O1, non-O139 Vibrio cholerae . However, laboratory tests have detected several serogroups, making it difficult determine the causative agent. Therefore, whole-genome analyses revealed that only serogroup O144 V. possesses a genomic island with type III secretion system (T3SS). A T3SS-deficient mutant was subsequently generated, and its pathogenicity assessed using rabbit ileal loop test. This led conclusion T3SS agent of outbreaks....
Vibrio parahaemolyticus is an important pathogen that causes food-borne gastroenteritis in humans. The type III secretion system encoded on chromosome 2 (T3SS2) plays a critical role the enterotoxic activity of V. parahaemolyticus. Previous studies have demonstrated T3SS2 induces actin stress fibers various epithelial cell lines during infection. This fiber formation strongly related to pathogenicity, but mechanisms underlie T3SS2-dependent and main effector not been elucidated. In this...
Resistance nodulation cell division (RND)-type efflux transporters play the main role in intrinsic resistance to various antimicrobial agents many gram-negative bacteria. Here, we estimated 12 RND-type transporter genes Vibrio parahaemolyticus. Because VmeAB has already been characterized, cloned other 11 and characterized them Escherichia coli KAM33 cells, a drug hypersusceptible strain. expressing either VmeCD, VmeEF, or VmeYZ showed increased minimum inhibitory concentrations (MICs) for...
ABSTRACT Twelve Vibrio cholerae isolates with genes for a type III secretion system (T3SS) were detected among 110 environmental and 14 clinical isolates. T3SS‐related distributed the various serogroups pulsed‐field gel electrophoresis of Not I‐digested genomes showed genetic diversity in these strains. However, restriction fragment length polymorphism profiles had similar patterns. Additionally, naturally competent T3SS‐negative V. incorporated ca. 47 kb gene cluster T3SS, which been...
The pathogenesis of the diarrheal disease caused by Vibrio parahaemolyticus, a leading cause seafood-associated enteritis worldwide, is dependent upon type III secretion system, T3SS2. This apparatus enables pathogen to inject bacterial proteins (effectors) into cytosol host cells and thereby modulate processes. T3SS effector transit cell via membrane pore (translocon) typically formed 3 proteins. We have identified third translocon protein for T3SS2: VopW, which was previously classified as...
Among three haemolysins identified thus far in Escherichia coli, alpha-haemolysin (HlyA) is encoded on the pathogenicity islands of extraintestinal pathogenic strains, while enterohaemolysin (EhxA) virulence plasmids enterohaemorrhagic E. coli (EHEC) strains. In contrast, gene for haemolysin E (HlyE) located chromosome backbone and therefore widely distributed among However, because hlyE expression repressed by H-NS protein has been disrupted many its haemolytic activity cannot be detected...
Many Gram-negative bacterial symbionts and pathogens employ a type III secretion system (T3SS) to live in contact with eukaryotic cells. Because T3SSs inject proteins (effectors) directly into host cells, the switching of secretory substrates between translocators effectors response cell attachment is crucial step for effective delivery effectors. Here, we show that protein switch Vibrio parahaemolyticus T3SS2, which main contributor enteropathogenicity food poisoning bacterium, regulated by...
Abstract A novel bacterial type III secretion effector, VopV, from the enteric pathogen Vibrio parahaemolyticus has been identified as a key factor in pathogenicity due to its interaction with cytoskeletal actin. One of repeat units long repetitive region named VopV rep1 , functions an actin-binding module. Despite importance pathogenesis, manner which effector binds actin and subsequent effects on dynamics remain unclear. Here, we report molecular basis /actin interaction. exists...
Abstract Background Understanding the source of typhoid infections and genetic relatedness Salmonella Typhi ( S . Typhi) by cluster identification in endemic settings is critical for establishing coordinated public health responses fever management. This study investigated genotypic diversity, antibiotic resistance mechanisms, clustering 35 S. strains isolated from cases carriers Mukuru Informal Settlement. Methods We studied .Typhi isolates, including 32 3 carriers, participants informal...