当前位置： SCI文献检索 > ENVIRONMENTAL MICROBIOLOGY期刊下所有文献 > Molecular characterization of thermostable direct haemolysin-related haemolysin (TRH)-positive Vibrio parahaemolyticus from oysters in Mangalore, India.

Molecular characterization of thermostable direct haemolysin-related haemolysin (TRH)-positive Vibrio parahaemolyticus from oysters in Mangalore, India.

Abstract：

:Pathogenic Vibrio parahaemolyticus strains producing either or both of a thermostable direct haemolysin (TDH) and a TDH-related haemolysin (TRH) encoded by tdh and trh genes, respectively, are isolated at a low rate from the environment. However, recently we observed that a considerable percentage of APW (alkaline peptone water) enrichment broths of oysters collected off Mangalore India, were trh(+), rather than tdh(+) by PCR. In order to further investigate the prevalence and genetic diversity of trh bearing V. parahaemolyticus in our coast, we attempted to isolate and characterize trh(+)V. parahaemolyticus from oysters. A total of 27 trh(+) strains were isolated during the period between March 2002 and February 2004, of which nine were also tdh(+). All the trh(+) isolates were positive for urease phenotype. The isolates belonged to diverse phenotypes. In order to explore the possible presence of heterogeneity in the trh gene region among trh(+)V. parahaemolyticus, a 1.5 kb region around trh gene was PCR amplified and restriction digested using selected restriction enzymes. The whole genome comparison of strains was performed by randomly amplified polymorphic DNA PCR (RAPD PCR). The PCR-RFLP results revealed fairly well conserved nature of the trh gene region studied in different serotypes. Though 11 strains were positive by PCR for a genomic fragment that has been reported to be amplified in pandemic strains, all strains were negative by group-specific PCR (GS-PCR), orf8 PCR and showed a different RAPD pattern compared with pandemic strains. The results suggest that genetically diverse V. parahaemolyticus carrying virulence genes are associated with the aquatic environment in this region.

journal_name

Environ Microbiol

journal_title

Environmental microbiology

authors

Parvathi A,Kumar HS,Bhanumathi A,Ishibashi M,Nishibuchi M,Karunasagar I,Karunasagar I

doi

10.1111/j.1462-2920.2006.00990.x

subject

Has Abstract

pub_date

2006-06-01 00:00:00

pages

997-1004

issue

eissn

1462-2912

issn

1462-2920

pii

EMI990

journal_volume

pub_type

杂志文章

在线工具

Molecular characterization of thermostable direct haemolysin-related haemolysin (TRH)-positive Vibrio parahaemolyticus from oysters in Mangalore, India.