Regulation of expression of photosynthetic genes by the two-component regulatory system of photosynthetic bacteria

1.克隆了类球红细菌双组分调控系统下游基因spb、orf 5、orf 318和ahcY. Spb是荚膜红细菌中hvrA的同源物，但其功能与Rba不同。spb中capsulatus是光抑制子，而hvrA是光激活子3。Orf 318是一个新基因，与细菌内脂多糖合成相关的糖基转移酶RfaI和RfaJ具有同源性.在有氧条件下，orf 5的破坏导致了黑暗中生长速率的抑制.在一株好氧光合细菌Roseobacteriumficans中，存在类似的基因，包括双组分调控基因，表明这些细菌的光合基因调控系统基本相同.所获得的结果表明，在信号转导途径的双组分调控基因的下游基因的可能参与。

1. Genes downstream of the two-component regulatory system of Rhodobacter sphaeroides were cloned and they were spb, orf 5, orf 318 and ahcY.2. Spb was a homologue of hvrA in Rhodobacter capsulatus but its function was differed from that of Rba. capsulatus in that spb was light-repressor, whereas hvrA was light-activator3. Orf 318 was a novel gene which had homology with RfaI and RfaJ, which are glycosyltransferases involved in the synthesis of lipopolysaccharide in bacteria.4. Disruption of orf 5 caused inhibition of growth rate in the dark under aerobic conditions.5. In an aerobic photosynthetic bacterium, Roseobacter denitrificans, there existed similar genes including two-component regulatory genes, indicating that the regulatory system for photosynthetic genes was essentially the same in these bacteria.6. The results obtained indicate the possible involvement of genes downstream of the two-component regulatory gene in the signal transduction pathway.