Bifunctional enzyme FBPase/SBPase is essential for photoautotrophic growth in cyanobacterium Synechocystis sp.PCC 6803  

作　　者：Chunlan Yan Xudong Xu 

机构地区：[1]The State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China

出　　处：《Progress in Natural Science:Materials International》2008年第2期149-153,共5页自然科学进展·国际材料（英文版）

基　　金：2007 National Natural Science Foundation of China;Chinese Academy of Sciences;National Natural Science Foundation of China(Grant No.30330030)

摘　　要：From a random insertion mutant library of Synechocystis sp. PCC 6803, a mutant defective in photoautotrophic growth was obtained. The interrupted gene was identified to be slr2094 （fbpl）, which encodes the fructose-1,6-biphosphatase （FBPase）/sedoheptulose-1,7-biphosphatase （SBPase） bifunctional enzyme （F-I）. Two other independently constructed slr2094 mutants showed an identical phenotype. The FBPase activity was found to be virtually lacking in an slr2094 mutant, which was sensitive to light under mixotrophic growth conditions. These results indicate that slr2094 is the only active FBPase-encoding gene in this cyanobacterium. Inactivation of photosystem II by interrupting psbB in slr2094 mutant alleviated the sensitiveness to light. This report provides the direct genetic evidence for the essential role of F-I in the photosynthesis of Synechocystis sp. PCC 6803.From a random insertion mutant library of Synechocystis sp. PCC 6803,a mutant defective in photoautotrophic growth was obtained. The interrupted gene was identified to be slr2094 (fbp1),which encodes the fructose-1,6-biphosphatase (FBPase)/sedoheptu-lose-1,7-biphosphatase (SBPase) bifunctional enzyme (F-I). Two other independently constructed slr2094 mutants showed an identical phenotype. The FBPase activity was found to be virtually lacking in an slr2094 mutant,which was sensitive to light under mixotrophic growth conditions. These results indicate that slr2094 is the only active FBPase-encoding gene in this cyanobacterium. Inactivation of photosystem Ⅱ by interrupting psbB in slr2094 mutant alleviated the sensitiveness to light. This report provides the direct genetic evi-dence for the essential role of F-I in the photosynthesis of Synechocystis sp. PCC 6803.

关 键 词：FBPASE Photoautotrophic growth Light sensitivity Synechocystis sp. 

分 类 号：Q93[生物学—微生物学]