title: Photorespiration participates in the assimilation of acetate in Chlorella sorokiniana under high light.
abstract: The development of microalgae on an industrial scale largely depends on the economic feasibility of mass production. High light induces productive suspensions during cultivation in a tubular photobioreactor. Herein, we report that high light, which inhibited the growth of Chlorella sorokiniana under autotrophic conditions, enhanced the growth of this alga in the presence of acetate. We compared pigments, proteomics and the metabolic flux ratio in C. sorokiniana cultivated under high light (HL) and under low light (LL) in the presence of acetate. Our results showed that high light induced the synthesis of xanthophyll and suppressed the synthesis of chlorophylls. Acetate in the medium was exhausted much more rapidly in HL than in LL. The data obtained from LC-MS/MS indicated that high light enhanced photorespiration, the Calvin cycle and the glyoxylate cycle of mixotrophic C. sorokiniana. The results of metabolic flux ratio analysis showed that the majority of the assimilated carbon derived from supplemented acetate, and photorespiratory glyoxylate could enter the glyoxylate cycle. Based on these data, we conclude that photorespiration provides glyoxylate to speed up the glyoxylate cycle, and releases acetate-derived CO2 for the Calvin cycle. Thus, photorespiration connects the glyoxylate cycle and the Calvin cycle, and participates in the assimilation of supplemented acetate in C. sorokiniana under high light.
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.|Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.|Tianjin Key Laboratory of Marine Resources and Chemistry, College of Marine Science and Engineering, Tianjin University of Science and Technology, Tianjin, 300457, China.
authors.forename: Xiujun
authors.initials: X
authors.lastname: Xie
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.|Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
authors.forename: Aiyou
authors.initials: A
authors.lastname: Huang
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.|Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
authors.forename: Wenhui
authors.initials: W
authors.lastname: Gu
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.
authors.forename: Zhengrong
authors.initials: Z
authors.lastname: Zang
authors.affiliation: Tianjin Key Laboratory of Marine Resources and Chemistry, College of Marine Science and Engineering, Tianjin University of Science and Technology, Tianjin, 300457, China.
authors.forename: Guanghua
authors.initials: G
authors.lastname: Pan
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.|Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
authors.forename: Shan
authors.initials: S
authors.lastname: Gao
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.|Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
authors.forename: Linwen
authors.initials: L
authors.lastname: He
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.|Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
authors.forename: Baoyu
authors.initials: B
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.|Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Niu
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.|Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
authors.forename: Apeng
authors.initials: A
authors.lastname: Lin
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.|Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
authors.forename: Guangce
authors.initials: G
authors.lastname: Wang
mesh_terms: D000064:Acclimatization / Q000187:drug effects; D000085:Acetates / Q000378:metabolism* / Q000494:pharmacology; D000596:Amino Acids / Q000378:metabolism; D002244:Carbon / Q000378:metabolism / Q000494:pharmacology; D002338:Carotenoids / Q000378:metabolism; D019069:Cell Respiration / Q000528:radiation effects*; D002708:Chlorella / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism* / Q000528:radiation effects*; D002734:Chlorophyll / Q000378:metabolism; D004227:Dithionite / Q000494:pharmacology; D005947:Glucose / Q000378:metabolism; D008027:Light; D010788:Photosynthesis / Q000187:drug effects; D010860:Pigments, Biological / Q000378:metabolism; D013312:Stress, Physiological / Q000187:drug effects / Q000528:radiation effects; D015854:Up-Regulation / Q000187:drug effects / Q000528:radiation effects
chemical_list: D000085:Acetates; D000596:Amino Acids; D010860:Pigments, Biological; D002734:Chlorophyll; D004227:Dithionite; D002338:Carotenoids; D002244:Carbon; D005947:Glucose
keywords: Calvin cycle; Chlorella sorokiniana; assimilation of acetate; glyoxylate cycle; photorespiration