Genetic analysis of the Enterococcus vancomycin resistance conjugative plasmid pHTbeta: identification of the region involved in cell aggregation and traB, a key regulator gene for plasmid transfer and cell aggregation.

ABSTRACT: The Enterococcus plasmid pHTbeta (63.7 kbp) is a pheromone-independent, highly conjugative pMG1-like plasmid that carries a Tn1546-like transposon encoding vancomycin resistance. The transfer-related regions (Tra I, Tra II, and Tra III) containing oriT and a putative nickase gene (traI) have previously been identified in pHTbeta, and in this study, we found that the plasmid conferred the ability to self-aggregate on the host strain Enterococcus faecalis FA2-2. A region where mutation resulted in the impairment of aggregation was identified and mapped to a point upstream of the transfer-related Tra I region. This region consisted of an approximately 6-kbp segment that contained the five open reading frames (ORFs) ORF9 to ORF13. These ORFs are considered to encode the aggregation function, a

SUBMITTER: Tomita H 

PROVIDER: S-EPMC2583617 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature