Characterization of DkaiC mutants of Pseudomonas putida KT2440/2 and Pseudomonas protegens CHA0

KaiC is the central cog of the circadian clock in Cyanobacteria. Close homologs of this protein are widespread among bacteria not known to have a circadian physiology. The function, interaction network, and mechanism of action of these KaiC homologs are still largely unknown. Here, we focus on KaiC homologs found in environmental Pseudomonas species. We characterize experimentally the only KaiC homolog present in Pseudomonas putida KT2440 and Pseudomonas protegens CHA0. Through phenotypic assays and transcriptomics, we show that KaiC is involved in osmotic and oxidative stress resistance in P. putida and in biofilm production in both P. putida and P. protegens. Overall design: Comparison of the transcriptome of the wild-type and DkaiC mutant of Pseudomonas putida KT2440/2 grown in LB to early, mid, and late stationary phase. Comparison of the transcriptome of the wild-type and DkaiC mutant of Pseudomonas protegens CHA0 grown in LB to late stationary phase.