Genomic and functional characterization of the modular broad-host-range RA3 plasmid, the archetype of the IncU group.

ABSTRACT: IncU plasmids are a distinctive group of mobile elements with highly conserved backbone functions and variable antibiotic resistance gene cassettes. The IncU archetype is conjugative plasmid RA3, whose sequence (45,909 bp) shows it to be a mosaic, modular replicon with a class I integron different from that of other IncU replicons. Functional analysis demonstrated that RA3 possesses a broad host range and can efficiently self-transfer, replicate, and be maintained stably in alpha-, beta-, and gammaproteobacteria. RA3 contains 50 open reading frames clustered in distinct functional modules. The replication module encompasses the repA and repB genes embedded in long repetitive sequences. RepA, which is homologous to antitoxin proteins from alpha- and gammaproteobacteria, contains a Cro/cI-ty

SUBMITTER: Kulinska A 

PROVIDER: S-EPMC2446526 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature