title: Metabolic flux ratio analysis and cell staining suggest the existence of C4 photosynthesis in Phaeodactylum tricornutum.
abstract: OBJECTIVE
  Mechanisms for carbon fixation via photosynthesis in the diatom Phaeodactylum tricornutum Bohlin were studied recently but there remains a long-standing debate concerning the occurrence of C4 photosynthesis in this species. A thorough investigation of carbon metabolism and the evidence for C4 photosynthesis based on organelle partitioning was needed.
  
  
  RESULTS
  In this study, we identified the flux ratios between C3 and C4 compounds in P. tricornutum using (13)C-labelling metabolic flux ratio analysis, and stained cells with various cell-permeant fluorescent probes to investigate the likely organelle partitioning required for single-cell C4 photosynthesis. Metabolic flux ratio analysis indicated the C3/C4 exchange ratios were high. Cell staining indicated organelle partitioning required for single-cell C4 photosynthesis might exist in P. tricornutum.
  
  
  CONCLUSIONS
  The results of (13)C-labelling metabolic flux ratio analysis and cell staining suggest single-cell C4 photosynthesis exists in P. tricornutum.
  
  
  CONCLUSIONS
  This study provides insights into photosynthesis patterns of P. tricornutum and the evidence for C4 photosynthesis based on (13)C-labelling metabolic flux ratio analysis and organelle partitioning.
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Science, Qingdao, Shandong, China.|Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
authors.forename: A
authors.initials: A
authors.lastname: Huang
authors.affiliation: Institute of Plant Physiology and Ecology, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.
authors.forename: L
authors.initials: L
authors.lastname: Liu
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Science, Qingdao, Shandong, China.
authors.forename: P
authors.initials: P
authors.lastname: Zhao
authors.affiliation: Institute of Plant Physiology and Ecology, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.
authors.forename: C
authors.initials: C
authors.lastname: Yang
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Science, Qingdao, Shandong, China.|Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
authors.forename: G C
authors.initials: GC
authors.lastname: Wang
mesh_terms: D002244:Carbon / Q000737:chemistry / Q000378:metabolism*; D002245:Carbon Dioxide / Q000378:metabolism; D017377:Diatoms / Q000378:metabolism*; D010788:Photosynthesis; D013194:Staining and Labeling
chemical_list: D002245:Carbon Dioxide; D002244:Carbon
keywords: C4 photosynthesis; Phaeodactylum tricornutum; cell staining; diatom; metabolic flux ratio analysis; organelle partitioning