Genetic diversity and molecular characterization of pathogenic Escherichia coli from different species of laboratory rodents

Abstract

Escherichia coli has been intensively studied under various aspects in general bacteriology. In this study, 10 RAPD primers were examined in pathogenic E. coli isolated from laboratory rodents like Swiss, PS, BALB/c, C₃H/J and SMA mice; SD, CF, DR, Wistar and Lew rats; Cotton rats, Mastomys and Mongolian gerbils suffering from diarrhoea to establish genetic diversity and molecular characterization in different rodent species. It has been found that the largest amplified products were 2000 bp and lowest 200 bp and the number of scorable bands for responding primers ranging from 1 to 8 with an average of four bands. A total of 6,724 bands were scored against 10 RAPD primers for E. coli in different rodent species. RBM 1 (RAPD primer) was amplified with 1000 bp bands in all rodent species. The dendogram revealed three groups among pathogenic E. coli strains of 13 rodent species which were almost similar except Wistar and SD rats due to their genetic diversity. The linkage distance between Wistar vs. SD was 0.06, and CF vs. Mastomys was 0.01. It is concluded that the pathogenic E. coli that may cause watery, non-bloody diarrhoea to watery-bloody diarrhoea and dysentery could be easily identifed using RBM 1 primer in laboratory rodents.