Core genome and plasmidome of the quorum-quenching bacterium Rhodococcus erythropolis.

Rhodococcus erythropolis is a worldwide-distributed actinobacterium that exhibits a remarkable metabolic versatility illustrated by its ability to degrade complex compounds, such as quorum-sensing signals N-acylhomoserine lactones (NAHLs), phenols, sterols and fuel derivatives. Because of its catabolic properties, R. erythropolis strains are proposed as anti-biofouling agents against NAHL-dependent biofilms, biocontrol agents against NAHL-emitting plant pathogens, and bioremediation agents in contaminated waters and soils. Here, we used the PacBio technology to resolve the complete genome sequence of the biocontrol strain R. erythropolis R138. Its genome consisted in a circular chromosome (6,236,862 bp), a linear plasmid pLRE138 (477,915 bp) and a circular plasmid pCRE138 (91,729 bp). In addition, draft genomes of five R. erythropolis strains were determined by Illumina technology and compared with the other five R. erythropolis genomes that are available in public databases: 5,825 common CDSs were present in all of the eleven analyzed genomes and represented up to 87 % of those identified in R. erythropolis R138. This study highlighted the high proportion of core-genome genes in R. erythropolis, but a high variability of the plasmid content. Key-metabolic pathways which are involved in the degradation of complex molecules, such as NAHLs and phenol, catechol and sterol derivatives are coded by the R. erythropolis core-genome.