Isolation and characterization of R-plasmid pPRS3a from Bacillus cereus GC subgroup a PRS3

Abstract

Bacillus cereus GC subgroup A was isolated from a metal rich environment and identified by Gram's staining, 16s rRNA sequencing (EU744603), phenotypic and biochemical characterization (MTCC10207) and fatty acid methyl esters (FAMEs) analysis. This bacterial strain harbors a plasmid DNA which was characterized by cloning into pET-28c(+) vector and sequenced through primer walking. The plasmid was named as pPRS3a and the size of plasmid was found to be 4126bp and possess Ampr gene, unique restriction sites for restriction endonuclease enzymes, strong promoters, origin of replication and three truncated ORFs. The complete nucleotide sequence of pPRS3a was submitted to NCBI GenBank under the accession no. GQ404376.1. It was found that pPRS3a has origin of replication (ori) which can be recognized by both Gram's positive and Gram's negative bacteria and pPRS3a stably maintained in both bacterial systems. Attempts to cure the plasmid from the strain could not be achieved and it suggests that the plasmid may have role in the metabolism. The distinctive characteristics of the plasmid exhibited by pPRS3a holds new promises for applications in the development of shuttle expression systems