Document Detail


Molecular cloning and stress-dependent expression of a gene encoding Delta(12)-fatty acid desaturase in the Antarctic microalga Chlorella vulgaris NJ-7.
MedLine Citation:
PMID:  19728010     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The psychrotrophic Antarctic alga, Chlorella vulgaris NJ-7, grows under an extreme environment of low temperature and high salinity. In an effort to better understand the correlation between fatty acid metabolism and acclimation to Antarctic environment, we analyzed its fatty acid compositions. An extremely high amount of Delta(12) unsaturated fatty acids was identified which prompted us to speculate about the involvement of Delta(12) fatty acid desaturase in the process of acclimation. A full-length cDNA sequence, designated CvFAD2, was isolated from C. vulgaris NJ-7 via reverse transcription polymerase chain reaction (RT-PCR) and RACE methods. Sequence alignment and phylogenetic analysis showed that the gene was homologous to known microsomal Delta(12)-FADs with the conserved histidine motifs. Heterologous expression in yeast was used to confirm the regioselectivity and the function of CvFAD2. Linoleic acid (18:2), normally not present in wild-type yeast cells, was detected in transformants of CvFAD2. The induction of CvFAD2 at an mRNA level under cold stress and high salinity is detected by real-time PCR. The results showed that both temperature and salinity motivated the upregulation of CvFAD2 expression. The accumulation of CvFAD2 increased 2.2-fold at 15 degrees C and 3.9-fold at 4 degrees C compared to the alga at 25 degrees C. Meanwhile a 1.7- and 8.5-fold increase at 3 and 6% NaCl was detected. These data suggest that CvFAD2 is the enzyme responsible for the Delta(12) fatty acids desaturation involved in the adaption to cold and high salinity for Antarctic C. vugaris NJ-7.
Authors:
Yandu Lu; Xiaoyuan Chi; Qingli Yang; Zhaoxin Li; Shaofang Liu; Qinhua Gan; Song Qin
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, Non-U.S. Gov't     Date:  2009-09-01
Journal Detail:
Title:  Extremophiles : life under extreme conditions     Volume:  13     ISSN:  1433-4909     ISO Abbreviation:  Extremophiles     Publication Date:  2009 Nov 
Date Detail:
Created Date:  2010-01-29     Completed Date:  2010-04-28     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  9706854     Medline TA:  Extremophiles     Country:  Germany    
Other Details:
Languages:  eng     Pagination:  875-84     Citation Subset:  IM; S    
Affiliation:
Yantai Institute of Coastal Zone Research for Sustainable Development, Chinese Academy of Sciences, Yantai, People's Republic of China. luyandu@webmail.hzau.edu.cn
Data Bank Information
Bank Name/Acc. No.:
GENBANK/EU596474;  GQ175318
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adaptation, Physiological / genetics*
Algal Proteins / genetics*,  isolation & purification
Amino Acid Sequence
Antarctic Regions
Chlorella vulgaris / enzymology,  genetics*
Cloning, Molecular
Cold Temperature
Conserved Sequence
DNA, Complementary / genetics
Fatty Acid Desaturases / genetics*,  isolation & purification
Molecular Sequence Data
Phylogeny
RNA, Messenger / biosynthesis,  genetics
Recombinant Fusion Proteins / biosynthesis
Saccharomyces cerevisiae
Salinity
Sequence Alignment
Sequence Homology, Amino Acid
Stress, Physiological / genetics
Chemical
Reg. No./Substance:
0/Algal Proteins; 0/DNA, Complementary; 0/RNA, Messenger; 0/Recombinant Fusion Proteins; EC 1.14.19.-/Fatty Acid Desaturases; EC 1.14.99.-/delta-12 fatty acid desaturase

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  A pilot trial of body weight reduction for nonalcoholic fatty liver disease with a home-based lifest...
Next Document:  Rapid deterioration of renal function in a patient with multiple myeloma associated with amyloid and...