title: Introducing extra NADPH consumption ability significantly increases the photosynthetic efficiency and biomass production of cyanobacteria.
abstract: Increasing photosynthetic efficiency is crucial to increasing biomass production to meet the growing demands for food and energy. Previous theoretical arithmetic analysis suggests that the light reactions and dark reactions are imperfectly coupled due to shortage of ATP supply, or accumulation of NADPH. Here we hypothesized that solely increasing NADPH consumption might improve the coupling of light reactions and dark reactions, thereby increasing the photosynthetic efficiency and biomass production. To test this hypothesis, an NADPH consumption pathway was constructed in cyanobacterium Synechocystis sp. PCC 6803. The resulting extra NADPH-consuming mutant grew much faster and achieved a higher biomass concentration. Analyses of photosynthesis characteristics showed the activities of photosystem II and photosystem I and the light saturation point of the NADPH-consuming mutant all significantly increased. Thus, we demonstrated that introducing extra NADPH consumption ability is a promising strategy to increase photosynthetic efficiency and to enable utilization of high-intensity lights.
authors: CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
authors: Jie
authors: J
authors: Zhou
authors: CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China.
authors: Fuliang
authors: F
authors: Zhang
authors: CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China; School of Life Sciences, University of Science and Technology of China, Hefei, China.
authors: Hengkai
authors: H
authors: Meng
authors: CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
authors: Yanping
authors: Y
authors: Zhang
authors: CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China. Electronic address: yli@im.ac.cn.
authors: Yin
authors: Y
authors: Li
mesh_terms: D049109:Cell Proliferation / Q000502:physiology*; D000458:Cyanobacteria / Q000166:cytology / Q000502:physiology* / Q000528:radiation effects; D024861:Genetic Enhancement / Q000379:methods*; D008027:Light; D060847:Metabolic Engineering / Q000379:methods*; D053858:Metabolic Networks and Pathways / Q000502:physiology*; D009249:NADP / Q000235:genetics / Q000378:metabolism*; D010788:Photosynthesis / Q000502:physiology* / Q000528:radiation effects
chemical_list: D009249:NADP
keywords: Energy balance; Extra NADPH consumption; Light/dark reactions cycle; Metabolic engineering; Photosynthetic efficiency