Comparative analysis of pandemic clone markers of Vibrio parahaemolyticus isolated from saline water fishes in Kolkata.

; "> Pandemic group of Vibrio parahaemolyticus possesses a variety of ‘unique’ DNA markers, like toxRS /new sequence (GS-PCR), orf-8 , a 930 bp AP-PCR fragment (PGS-PCR) and various other markers. In the present study, initially 94 tdh + and trh - (virulent), then 75 toxR + (speciesspecific), V. parahaemolyticus isolates from saline water fishes of Kolkata Metropolis based fish markets were analyzed for the presence of three pandemic markers viz ., toxRS /new region (GSPCR), orf-8 and PGS-PCR. Out of 94 tdh + isolates, 58 (61.7%) were positive for toxRS/ new region in GS-PCR. None of the isolates were positive for the orf-8 gene; however, in PGS-PCR assay all tested isolates ( tdh + ) were positive. But when 75 toxR + non-virulent isolates were tested by all these three markers, no isolate was found positive for GS-PCR and orf-8 PCR; however, all were found positive in PGS-PCR. Thus, from the present study it may be inferred that only GS-PCR is a suitable marker for identification of pandemic group; while, orf-8 and PGS-PCR assay might not be appropriate.