Biosynthesis of Triacylglycerol Molecules with a Tailored PUFA Profile in Industrial Microalgae

Yi Xin; Chen Shen; Yiting She; Hong Chen; Cong Wang; Li Wei; Kangsup Yoon; Danxiang Han; Qiang Hu; Jian Xu

doi:10.1016/j.molp.2018.12.007

Biosynthesis of Triacylglycerol Molecules with a Tailored PUFA Profile in Industrial Microalgae

Mol Plant. 2019 Apr 1;12(4):474-488. doi: 10.1016/j.molp.2018.12.007. Epub 2018 Dec 20.

Authors

Yi Xin¹, Chen Shen¹, Yiting She¹, Hong Chen², Cong Wang³, Li Wei¹, Kangsup Yoon², Danxiang Han², Qiang Hu⁴, Jian Xu⁵

Affiliations

¹ Single-Cell Center, CAS Key Laboratory of Biofuels and Shandong Laboratory of Energy Genetics, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266237, China; University of Chinese Academy of Sciences, Beijing 100049, China.
² Center for Microalgal Biotechnology and Biofuels, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei 430072, China.
³ Core Laboratory, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, China.
⁴ Center for Microalgal Biotechnology and Biofuels, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei 430072, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266237, China.
⁵ Single-Cell Center, CAS Key Laboratory of Biofuels and Shandong Laboratory of Energy Genetics, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266237, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: xujian@qibebt.ac.cn.

PMID: 30580039
DOI: 10.1016/j.molp.2018.12.007

Abstract

The composition of polyunsaturated fatty acids (PUFAs) in triacylglycerols (TAGs) is key to health benefits and for oil applications, yet the underlying genetic mechanism remains poorly understood. In this study, by in silico, ex vivo, and in vivo profiling of type-2 diacylglycerol acyltransferases (DGAT2s) in Nannochloropsis oceanica we revealed two novel PUFA-preferring enzymes that discriminate individual PUFA species in TAG assembly, with NoDGAT2J for linoleic acid (LA) and NoDGAT2K for eicosapentaenoic acid (EPA). The LA and EPA composition of TAG molecules is mediated in vivo via the functional partitioning between NoDGAT2J and 2K, both of which are localized in the chloroplast envelope. By modulating transcript abundance of the DGAT2s, an N. oceanica strain bank was created, where proportions of LA and EPA in TAG vary by 18.7-fold (between 0.21% and 3.92% dry weight) and 34.7-fold (between 0.09% and 3.12% dry weight), respectively. These findings lay the foundation for producing designer TAG molecules with tailored health benefits or for biofuel applications in industrial microalgae and higher-plant crops.

Keywords: Nannochloropsis oceanica; diacylglycerol acyltransferase; microalgae; polyunsaturated fatty acids.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Diacylglycerol O-Acyltransferase / deficiency
Diacylglycerol O-Acyltransferase / genetics
Diacylglycerol O-Acyltransferase / metabolism
Evolution, Molecular
Fatty Acids, Unsaturated / metabolism*
Gene Knockdown Techniques
Industry*
Intracellular Space / metabolism
Microalgae / cytology
Microalgae / genetics
Microalgae / metabolism*
Protein Transport
Substrate Specificity
Triglycerides / biosynthesis*

Substances

Fatty Acids, Unsaturated
Triglycerides
Diacylglycerol O-Acyltransferase