Proteomic and biochemical responses to different concentrations of CO2 suggest the existence of multiple carbon metabolism strategies in Phaeodactylum tricornutum

Biotechnology for Biofuels

Guangce Wang¹  Wenhui Gu¹  Songcui Wu¹  Lijun Wang¹  Aiyou Huang²  Lu Zhou³  Shuao Jia³  Xuehua Liu³  Lepu Wang³ 

[1] CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, 266071, Qingdao, China;Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, 266071, Qingdao, China;CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, 266071, Qingdao, China;Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, 266071, Qingdao, China;College of Marine Sciences, Hainan University, 570228, Haikou, China;CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, 266071, Qingdao, China;Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, 266071, Qingdao, China;University of Chinese Academy of Sciences, 100049, Beijing, China;

关键词: CO-concentrating mechanism;    C4-like photosynthetic pathway;    CO;    Carbon metabolism responses;    Phaeodactylum tricornutum;   

DOI  :  10.1186/s13068-021-02088-5

来源: Springer

【 摘 要 】

BackgroundDiatoms are well known for high photosynthetic efficiency and rapid growth rate, which are not only important oceanic primary producer, but also ideal feedstock for microalgae industrialization. Their high success is mainly due to the rapid response of photosynthesis to inorganic carbon fluctuations. Thus, an in-depth understanding of the photosynthetic carbon fixation mechanism of diatoms will be of great help to microalgae-based applications. This work directed toward the analysis of whether C4 photosynthetic pathway functions in the model marine diatom Phaeodactylum tricornutum, which possesses biophysical CO2-concentrating mechanism (CCM) as well as metabolic enzymes potentially involved in C4 photosynthetic pathway.ResultsFor P. tricornutum, differential proteome, enzyme activities and transcript abundance of carbon metabolism-related genes especially biophysical and biochemical CCM-related genes in response to different concentrations of CO2 were tracked in this study. The upregulated protein abundance of a carbonic anhydrases and a bicarbonate transporter suggested biophysical CCM activated under low CO2 (LC). The upregulation of a number of key C4-related enzymes in enzymatic activity, transcript and protein abundance under LC indicated the induction of a mitochondria-mediated CCM in P. tricornutum. Moreover, protein abundance of a number of glycolysis, tricarboxylic acid cycle, photorespiration and ornithine–urea cycle related proteins upregulated under LC, while numbers of proteins involved in the Calvin cycle and pentose phosphate pathway were downregulated. Under high CO2 (HC), protein abundance of most central carbon metabolism and photosynthesis-related proteins were upregulated.ConclusionsThe proteomic and biochemical responses to different concentrations of CO2 suggested multiple carbon metabolism strategies exist in P. tricornutum. Namely, LC might induce a mitochondrial-mediated C4-like CCM and the improvement of glycolysis, tricarboxylic acid cycle, photorespiration and ornithine–urea cycle activity contribute to the energy supply and carbon and nitrogen recapture in P. tricornutum to cope with the CO2 limitation, while P. tricornutum responds to the HC environment by improving photosynthesis and central carbon metabolism activity. These findings can not only provide evidences for revealing the global picture of biophysical and biochemical CCM in P. tricornutum, but also provide target genes for further microalgal strain modification to improve carbon fixation and biomass yield in algal-based industry.

【 授权许可】

CC BY