The thermostable direct hemolysin-related hemolysin (trh) gene of Vibrio parahaemolyticus: Sequence variation and implications for detection and function.
Vibrio parahaemolyticus is a leading cause of bacterial food-related illness associated with the consumption of undercooked seafood. Only a small subset of strains is pathogenic. Most clinical strains encode for the thermostable direct hemolysin (TDH) and/or the TDH-related hemolysin (TRH). In this work, we amplify and sequence the trh gene from over 80 trh+strains of this bacterium and identify thirteen genetically distinct alleles, most of which have not been deposited in GenBank previously. Sequence data was used to design new primers for more reliable detection of trh by endpoint PCR. We also designed a new quantitative PCR assay to target a more conserved gene that is genetically-linked to trh. This gene, ureR, encodes the transcriptional regulator for the urease gene cluster immediately upstream of trh. We propose that this ureR assay can be a useful screening tool as a surrogate for direct detection of trh that circumvents challenges associated with trh sequence variation.
Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA, 2725 Montlake Blvd. E., Seattle, WA 98112, USA. Electronic address: william.nilsson@noaa.gov.
William B
WB
Nilsson
Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA, 2725 Montlake Blvd. E., Seattle, WA 98112, USA.
Jeffrey W
JW
Turner
D000483:Alleles; D001426:Bacterial Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D001427:Bacterial Toxins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D001483:Base Sequence; D017931:DNA Primers; D014644:Genetic Variation; D006460:Hemolysin Proteins / Q000235:genetics* / Q000302:isolation & purification* / Q000378:metabolism; D006801:Humans; D010802:Phylogeny; D060888:Real-Time Polymerase Chain Reaction; D014510:Urease / Q000235:genetics; D014735:Vibrio Infections / Q000382:microbiology; D014736:Vibrio parahaemolyticus / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D017931:DNA Primers; D006460:Hemolysin Proteins; C068489:thermostable direct hemolysin; D014510:Urease
Detection; PCR; Sequence variation; V. parahaemolyticus; trh