title: Special biochemical responses to nitrogen deprivation of filamentous oleaginous microalgae Tribonema sp.
abstract: Both filamentous microalgae Tribonema and unicellular microalgae Nanochloropsis are promising feedstock for biodiesel production. Nitrogen starvation increased lipid content in Nannochloropsis but decreased that in Tribonema. In this study, biochemical responses of Tribonema under different levels of nitrogen (0N, 0.05N, 0.1N and 1N-BG11) were investigated. 1N-BG11 was sufficient during 15-day-cultivation, while the other levels were nitrogen limited. Cell growth was interrupted with 0N-BG11, but no differences in biomass among 0.05N, 0.1N and 1N-BG11. Both protein and lipid contents (% of dry weight) declined gradually inversely to the increment in carbohydrate contents under the decreasement of nitrogen levels. Both assays and TEM results showed that the cytoplasm in Tribonema contained no starch. Compared to nitrogen-replete condition, the TAG content (% of dry weight) decreased obviously under nitrogen starvation. Different levels of nitrogen did not cause fundamental shifts in fatty acid profiles in Tribonema.
authors.affiliation: CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Fajin
authors.initials: F
authors.lastname: Guo
authors.affiliation: CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, PR China. Electronic address: wanghui@qibebt.ac.cn.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.affiliation: CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, PR China.
authors.forename: Junfeng
authors.initials: J
authors.lastname: Wang
authors.affiliation: CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, PR China.
authors.forename: Wenjun
authors.initials: W
authors.lastname: Zhou
authors.affiliation: CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, PR China.
authors.forename: Lili
authors.initials: L
authors.lastname: Gao
authors.affiliation: CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, PR China.
authors.forename: Lin
authors.initials: L
authors.lastname: Chen
authors.affiliation: CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, PR China.
authors.forename: Qingzhe
authors.initials: Q
authors.lastname: Dong
authors.affiliation: CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.affiliation: CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, PR China. Electronic address: liutz@qibebt.ac.cn.
authors.forename: Tianzhong
authors.initials: T
authors.lastname: Liu
mesh_terms: D018533:Biomass; D003470:Culture Media; D005227:Fatty Acids / Q000378:metabolism; D046529:Microscopy, Electron, Transmission; D009584:Nitrogen / Q000378:metabolism*; D058009:Stramenopiles / Q000254:growth & development / Q000378:metabolism*; D014280:Triglycerides / Q000378:metabolism
chemical_list: D003470:Culture Media; D005227:Fatty Acids; D014280:Triglycerides; D009584:Nitrogen
keywords: Carbohydrate; Fatty acid; Lipid; Nitrogen starvation; Tribonema