Virulence Factors and Molecular cloning of Outer Membrane Protein (OMP) gene from virulent Aeromonas hyrophila isolated from infected gold fish Carassius auratus

Abstract

Aeromonas hyrophila strains AHV1, AHV2 and AH3 were isolated and identified from Muscle tissue, intestine, body fluid and gills of infected gold fish Carassius auratus. In order to study their virulence, LD₅₀ tests against  normal gold fish, proteolytic, haemolytic and challenge studies were performed. The virulence studies revealed that, both AHV1 and AHV2 strains are highly positive for proteolytic and haemolytic properties. The LD₅₀ data showed that, the fish C. auratus are highly susceptible to A. hyrophila strains AHV1 and AHV2 at cent percent lethal rate. The survival of C. auratus significantly (P<0.05) decreased when challenged with virulent strains of A. hydrophila AHV1 and AHV2. The outer membrane protein (OMP-TS) gene was successfully amplified generating an the amplicon size of 1008 bp. The amplified product from the genomic DNA of AHV1 strain was cloned in to pTZ57R/T vector, transformed into DH₅? cells and sequenced. The sequenced clone is resembling to various A. hydrophila isolates and submitted to NCBI GenBank database (accession no:HQ331525).

DOI: http://dx.doi.org/10.3329/bjm.v28i2.11819

Bangladesh J Microbiol, Volume 28, Number 2, December 2011, pp 70-75