title: A type 2 diacylglycerol acyltransferase accelerates the triacylglycerol biosynthesis in heterokont oleaginous microalga Nannochloropsis oceanica.
abstract: Oleaginous microalgae have received a considerable attention as potential biofuel feedstock. However, lack of industry-suitable strain with lipid rich biomass limits its commercial applications. Targeted engineering of lipogenic pathways represents a promising strategy to enhance the efficacy of microalgal oil production. In this study, a type 2 diacylglycerol acyltransferase (DGAT), a rate-limiting enzyme in triacylglycerol (TAG) biosynthesis, was identified and overexpressed in heterokont oleaginous microalga Nannochloropsis oceanica for the first time. Overexpression of DGAT2 in Nannochloropsis increased the relative transcript abundance by 3.48-fold in engineered microalgae cells. TAG biosynthesis was subsequently accelerated by DGAT2 overexpression and neutral lipid content was significantly elevated by 69% in engineered microalgae. The fatty acid profile determined by GC-MS revealed that fatty acid composition was altered in engineered microalgae. Saturated fatty acids and polyunsaturated fatty acids were found to be increased whereas monounsaturated fatty acids content decreased. Furthermore, DGAT2 overexpression did not show negative impact on algal growth parameters. The present investigation showed that the identified DGAT2 would be a potential candidate for enhancing TAG biosynthesis and might facilitate the development of promising oleaginous strains with industrial potential.
authors.affiliation: Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science, Jinan University, Guangzhou 510632, China.
authors.forename: Da-Wei
authors.initials: DW
authors.lastname: Li
authors.affiliation: Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science, Jinan University, Guangzhou 510632, China.
authors.forename: Shi-Ying
authors.initials: SY
authors.lastname: Cen
authors.affiliation: Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science, Jinan University, Guangzhou 510632, China.
authors.forename: Yu-Hong
authors.initials: YH
authors.lastname: Liu
authors.affiliation: Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science, Jinan University, Guangzhou 510632, China.
authors.forename: Srinivasan
authors.initials: S
authors.lastname: Balamurugan
authors.affiliation: Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science, Jinan University, Guangzhou 510632, China.
authors.forename: Xin-Yan
authors.initials: XY
authors.lastname: Zheng
authors.affiliation: Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science, Jinan University, Guangzhou 510632, China.
authors.forename: Adili
authors.initials: A
authors.lastname: Alimujiang
authors.affiliation: Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science, Jinan University, Guangzhou 510632, China.
authors.forename: Wei-Dong
authors.initials: WD
authors.lastname: Yang
authors.affiliation: Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science, Jinan University, Guangzhou 510632, China.
authors.forename: Jie-Sheng
authors.initials: JS
authors.lastname: Liu
authors.affiliation: Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science, Jinan University, Guangzhou 510632, China. Electronic address: thyli@jnu.edu.cn.
authors.forename: Hong-Ye
authors.initials: HY
authors.lastname: Li
mesh_terms: D051048:Diacylglycerol O-Acyltransferase / Q000032:analysis / Q000235:genetics* / Q000378:metabolism; D060847:Metabolic Engineering / Q000379:methods*; D058086:Microalgae / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D058009:Stramenopiles / Q000201:enzymology* / Q000378:metabolism*; D014280:Triglycerides / Q000032:analysis / Q000096:biosynthesis*
chemical_list: D014280:Triglycerides; D051048:Diacylglycerol O-Acyltransferase
keywords: Biofuel; DGAT; Microalga; Triacylglycerol