Abstract
In Synechocystis sp. PCC 6803, ssl0564 encodes a small (89 amino acid residues) transcriptional regulator that contains a helix-turn-helix DNA-binding motif of LuxR family. Although many bacteria possess ORFs encoding such small transcriptional regulators, these ORFs have not been characterized except for gerE, the transcriptional regulator for spore formation in Bacillus subtilis. In order to know the physiological role of ssl0564 in Synechocystis sp. PCC 6803, we compared the growth property of ssl0564-disrupted mutant with that of the wild type under various conditions. The mutant did not show any phenotype under the conditions of high light, oxidative, high salt and heat shock stress. Under nitrogen-depleted conditions, however, drastic decrease in phycocyanin content was observed only in the mutant. DNA microarray analysis under nitrogen-depleted conditions will be performed to clarify the role of ssl0564 in transcriptional regulation.
