Diversity of DNA Sequences Among Restriction Endonucleases Producing Selenomonas ruminantium Isolates Detected by Enterobacterial Repetitive Intergenic Consensus Based Polymerase Chain Reaction (ERIC-PCR)

Abstract Enterobacterial repetitive intergenic consensus-based polymerase chain reaction (ERIC-PCR) was found useful for discrimination of rumen selenomonads. Simultaneous use of ERICIR and ERIC2 primers yielded strain-specific banding patterns. The patterns were compared using Dice similarity coefficients and a DNA relatedness dendrogram based on the unweighted pair group method using arithmetic averages (UPGMA) was constructed. Five clusters and four single strains were identified at a similarity level of 50%. Very weak grouping was observed for lactilytica and ruminantium subspecies of Selenomonas ruminantium , indicating that lactate utilization has probably no taxonomic value. Restriction and modification phenotypes are weakly reflected in the dendrogram probably as the result of horizontal genetic transfer of genes encoding these phenotypic traits. While diverse in ERIC-PCR analysis, strains shown little variation in restriction fragment length polymorphism of amplified 16S-rRNA genes. All but one strain produced nearly identical profile indicating that majority of DNA diversity observed is due to epigenetic factors and not due to evolutionary divergence.