title: Enhanced fatty acid accumulation in Isochrysis galbana by inhibition of the mitochondrial alternative oxidase pathway under nitrogen deprivation.
abstract: The purpose of this study was to clarify the interrelation between the mitochondrial alternative oxidase (AOX) pathway and fatty acid accumulation in marine microalga Isochrysis galbana. Under normal conditions, the activity of the AOX pathway was maintained at a low level in I. galbana. Compared with the normal condition, nitrogen deprivation significantly increased the AOX pathway activity and fatty acid accumulation. Under nitrogen deprivation, the inhibition of the AOX pathway by salicylhydroxamic acid caused the accumulation of reducing equivalents and the over-reduction of chloroplasts in I. galbana cells, leading to a decrease in the photosynthetic O2 evolution rate. The over-production of reducing equivalents due to the inhibition of the AOX pathway under nitrogen deprivation further enhanced the accumulation of fatty acids in I. galbana cells.
authors.affiliation: Key Laboratory of Experimental Marine Biology, National-Local Joint Engineering Research Center for Breeding New Varieties of Haematococcus pluvialis and Developing Astaxanthin-enriched Products, 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: Litao
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Experimental Marine Biology, National-Local Joint Engineering Research Center for Breeding New Varieties of Haematococcus pluvialis and Developing Astaxanthin-enriched Products, 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. Electronic address: jgliu@qdio.ac.cn.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Liu
mesh_terms: D005227:Fatty Acids / Q000378:metabolism*; D058087:Haptophyta / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000378:metabolism*; D009584:Nitrogen / Q000737:chemistry / Q000378:metabolism; D010088:Oxidoreductases / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism*; D000099188:Alternative Oxidase
chemical_list: D005227:Fatty Acids; D024101:Mitochondrial Proteins; D009584:Nitrogen; D010088:Oxidoreductases; D010940:Plant Proteins; D000099188:Alternative Oxidase
keywords: Alternative oxidase; Fatty acid accumulation; Nitrogen deprivation; Reducing equivalents