Cloning and characterization of a delta-6 desaturase encoding gene from Nannochloropsis oculata  

作　　者：马晓磊 俞建中 朱葆华 潘克厚 潘瑾 杨官品 

机构地区：[1]Lab of Applied Microalgae Biology,the Key Laboratory of Aquaculture,Ministry of Education,Ocean University of China [2]College of Marine Life Sciences,Ocean University of China

出　　处：《Chinese Journal of Oceanology and Limnology》2011年第2期290-296,共7页中国海洋湖沼学报（英文版）

基　　金：Supported by the National Key Technology R&D Program in the 11th Five-Year Plan of China (No. 2006BAD09A03-2);the National High-tech Research and Development Program of China(863 Program) (No. 2007AA09Z427)

摘　　要：A gene （NANOC-D6D） encoding a desaturase that removes two hydrogen atoms from fatty acids at delta 6 position was isolated from a cDNA library of Nannochloropsis oculata （Droop） D. J. Hibberd （Eustigmatophyceae）. The unicellular marine microalga N. oculata synthesizes rich long chain polyunsaturated fatty acids （LCPUFAs）, including eicosapentaenoic acid （20：5n-3, EPA）. The deduced protein contains 474 amino acids that fold into 4 trans-membrane domains. The neighbor-joining phylogenetic tree indicates that NANOC-D6D is phylogenetically close to the delta-6 fatty acid desaturase of marine microalgae such as Glossomastix chrysoplasta, Thalassiosira pseudonana, and Phaeodactylum tricornutum. The gene was expressed in Saccharomyces cerevisiae INVScl to verify the substrate specificity of NAN OC-D6D. Our results suggest that the recombinant NANOC-D6D simultaneously desaturates linoleic acid （LA） and a-linolenic acid （ALA）.A gene(NANOC-D6D) encoding a desaturase that removes two hydrogen atoms from fatty acids at delta 6 position was isolated from a cDNA library of Nannochloropsis oculata(Droop) D.J.Hibberd(Eustigmatophyceae).The unicellular marine microalga N.oculata synthesizes rich long chain polyunsaturated fatty acids(LCPUFAs),including eicosapentaenoic acid(20:5n-3,EPA).The deduced protein contains 474 amino acids that fold into 4 trans-membrane domains.The neighbor-joining phylogenetic tree indicates that NANOC-D6D is phylogenetically close to the delta-6 fatty acid desaturase of marine microalgae such as Glossomastix chrysoplasta,Thalassiosira pseudonana,and Phaeodactylum tricornutum.The gene was expressed in Saccharomyces cerevisiae INVSc1 to verify the substrate specificity of NANOC-D6D.Our results suggest that the recombinant NANOC-D6D simultaneously desaturates linoleic acid(LA) and a-linolenic acid(ALA).

关 键 词：MICROALGAE Nannochloropsis oculata EPA delta-6 desaturase gene expression 

分 类 号：Q946.5[生物学—植物学]