Genetic Characterization of Aeromonas hydrophila using Protein Profiling and RAPD PCR

Abstract

Genetic relationship among Aeromonas hydrophila isolates from fish and traditional brackishwater farms were evaluated through Randomly Amplified Polymorphic DNA (RAPD) analysis as well as Sodium Dodecyl Sulphate-Polyacrylamide Gel Electrophoresis (SDS PAGE) profile of cellular proteins. PCR amplification of the DNA from the bacterial isolates using five random primers (OPA-01, 03, 04, 05 and 10) produced 46 amplicons, which were scorable as distinct bands on agarose gel electrophoresis. Absolute polymorphism of RAPD profile was evident with a unique pattern for each isolate, indicating its usefulness as an ideal tool for evaluation of genetic heterogeneity within the species, which are not revealed by other methods like morphological and biochemical characterization and cellular protein profile. Cellular protein profile did not reveal significant polymorphism as all the isolates revealed uniform pattern indicating its usefulness as a tool for species level identification. Four protein bands of molecular size viz., 19.5 kDa, 25.6 kDa, 29 kDa and 65.6 kDa were shared by all the isolates in the study.