title: Global Metabolic Regulation of the Snow Alga Chlamydomonas nivalis in Response to Nitrate or Phosphate Deprivation by a Metabolome Profile Analysis.
abstract: In the present work, Chlamydomonas nivalis, a model species of snow algae, was used to illustrate the metabolic regulation mechanism of microalgae under nutrient deprivation stress. The seed culture was inoculated into the medium without nitrate or phosphate to reveal the cell responses by a metabolome profile analysis using gas chromatography time-of-flight mass spectrometry (GC/TOF-MS). One hundred and seventy-one of the identified metabolites clustered into five groups by the orthogonal partial least squares discriminant analysis (OPLS-DA) model. Among them, thirty of the metabolites in the nitrate-deprived group and thirty-nine of the metabolites in the phosphate-deprived group were selected and identified as "responding biomarkers" by this metabolomic approach. A significant change in the abundance of biomarkers indicated that the enhanced biosynthesis of carbohydrates and fatty acids coupled with the decreased biosynthesis of amino acids, N-compounds and organic acids in all the stress groups. The up- or down-regulation of these biomarkers in the metabolic network provides new insights into the global metabolic regulation and internal relationships within amino acid and fatty acid synthesis, glycolysis, the tricarboxylic acid cycle (TCA) and the Calvin cycle in the snow alga under nitrate or phosphate deprivation stress.
authors.affiliation: School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China. lvnahzau@gmail.com.
authors.forename: Na
authors.initials: N
authors.lastname: Lu
authors.affiliation: School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China. handcj@126.com.
authors.forename: Jun-Hui
authors.initials: JH
authors.lastname: Chen
authors.affiliation: School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China. fewd304@scut.edu.cn.
authors.forename: Dong
authors.initials: D
authors.lastname: Wei
authors.affiliation: School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China. sfchencoe@pku.edu.cn.|Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China. sfchencoe@pku.edu.cn.
authors.forename: Feng
authors.initials: F
authors.lastname: Chen
authors.affiliation: School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China. chengu@scut.edu.cn.
authors.forename: Gu
authors.initials: G
authors.lastname: Chen
mesh_terms: D002696:Chlamydomonas / Q000378:metabolism*; D055442:Metabolome; D009566:Nitrates / Q000378:metabolism*; D009584:Nitrogen / Q000172:deficiency; D010710:Phosphates / Q000172:deficiency*; D013312:Stress, Physiological
chemical_list: D009566:Nitrates; D010710:Phosphates; D009584:Nitrogen
keywords: Chlamydomonas nivalis; GC/TOF-MS; OPLS-DA; metabolome profile; nutrient deprivation; responding biomarker