Abstract
Two component signal transduction is the primary signal transduction mechanism used to conduct global regulation of the cells responses to changes in the environment. DNA microarray analysis has identified genes up-regulated by acid stress in cyanobacteria Synechocystis sp. PCC 6803. Some of the genes, it has been proposed that response regulators are directly involved in the stress. The deletion mutants of these genes have been established and the acid tolerance evaluated. Among these mutants, deletion of slr0081 affected growth rate in acid stress condition of pH 6.0. We examined the genome-wide expression of genes in Δslr0081 mutant cells using DNA microarrays in an attempt to distinguish whether slr0081 involves in the regulation of other acid stress responsive genes expression. From the array data, we found the down regulation of acid responsible genes (slr0967 and sll0939) by deletion of slr0081.