Plasmid manipulation of bacterial behaviour through translational regulatory crosstalk

pQBR103 is a naturally occurring plasmid known to alter the behaviour of its host, Pseudomonas fluorescens. This plasmid encodes a predicted translational regulator, rsmQ which is a homologue of known global regulators within Pseudomonas. Within this study we compared Pseudomonas fluorescens SBW25 plasmid free cells with cells carrying either WT pQBR103 or pQBR103 lacking rsmQ. Using comparative quantitative proteomics and RNAseq we showed that the loss of rsmQ leads to widespread proteomic changes in the absence of changes in mRNA abundance, suggesting RsmQ is a translational regulator of its host chromosome.