Abstract
Among several Plastid Specific Ribosomal Proteins (PSRPs), PSRP-1-like proteins are distributed in most bacteria. PSRP-1-like proteins in E coli, HPF and YfiA, were involved in dimer ribosome formation and translation inhibition.
We isolated a psrp-1 disruptant and an overexpression strain of Synechocystis sp. PCC 6803. Growth of either strain was similar to that of wild-type strain in liquid media at 30 degree or 40 degree, and in light-dark cycle or continuous light. In the competition culture between wild-type and psrp-1 disruptant in liquid media at 30 degree, psrp-1 disruptant gradually became dominant in the population, suggesting PSRP-1 moderately suppresses cell growth. On the other hand, growth of the psrp-1 disruptant was remarkably suppressed in the competition culture on solid media. These results suggest that PSRP-1 confer resistant to a kind of stress which may be related to growth condition on solid media. We then examined ribosome profiles of cell culture and found that dimer ribosomes were detected in the cells grown on solid media or grown at high temperature.
