Transcriptomic and proteomic profiling of Rhodospirillum rubrum M68 cultivated in MELiSSA related culture conditions. Rhodospirillum rubrum

In the context of the Micro-Ecological Life Support System Alternative (MELiSSA) project, the quorum sensing system (QS) of R. rubrum S1H has been shown to rely on acyl homoserine lactones (AHLs) as communication signals. In addition, previous studies in our lab have suggested that pigment content and photosynthetic membrane production could be under the control of QS. In the present study, the transcriptomic and proteomic profiles of a QS-deficient mutant (R. rubrum strain M68) that does not produce AHLs as the WT strain (R. rubrum S1H) were compared when cultivated in light anaerobic conditions using acetate as carbon source. Transcriptomic and proteomic approaches revealed that 330 genes and 217 proteins were differentially expressed in M68 compared to S1H, indicating that several operons were QS-regulated i.e. flagellar assembly, chemotaxis, photosynthesis, electron transport, stress proteins. These results showed the importance of a functional QS system in R. rubrum. Overall design: Comparison of the expression of two R. rubrum cultures