Molecular characterization of a novel isolate of Candida tropicalis for enhanced lipid production
Article first published online: 4 FEB 2013
© 2013 The Society for Applied Microbiology No claim to other Government works
Journal of Applied Microbiology
Volume 114, Issue 5, pages 1357–1368, May 2013
How to Cite
Dey, P. and Maiti, M.K. (2013), Molecular characterization of a novel isolate of Candida tropicalis for enhanced lipid production. Journal of Applied Microbiology, 114: 1357–1368. doi: 10.1111/jam.12133
- Issue published online: 15 APR 2013
- Article first published online: 4 FEB 2013
- Accepted manuscript online: 14 JAN 2013 04:10AM EST
- Manuscript Revised: 4 JAN 2013
- Manuscript Accepted: 4 JAN 2013
- Manuscript Received: 18 AUG 2012
- Candida tropicalis ;
- lipid production;
- nitrogen stress;
- oleaginous yeast;
- transcriptional regulation of genes
To characterize a new isolate of Candida tropicalis for its enhanced storage lipid accumulation with respect to lipid composition, fatty acid profile and transcriptional regulation of four key genes involved in lipid productivity using different carbon sources.
Methods and Results
Upon growing C. tropicalis on various carbon substrates, glucose was found to be the best followed by xylose for the production of both biomass and storage lipid. On glucose (100 g l−1) medium having specific nitrogen stress (C:N 150 : 1), the yeast was capable of yielding about 58% lipid content of its dry biomass, and neutral lipid accounted for about 75% of the total lipid. Fatty acid profiles revealed that the glucose contributed to the highest yield of total fatty acids, maximum proportion of saturated fatty acids and a significant amount of oleic acid. The enhanced lipid production with specific fatty acid profile correlated with the strong upregulation of acetyl Co-A carboxylase, stearoyl-ACP desaturase and diacylglycerol acyltransferase genes, but not the malic enzyme gene.
Together, the results documented the differential regulation of four genes of lipid biosynthesis in the newly isolated C. tropicalis oleaginous strain by various carbon sources.
Significance and Impact of the Study
We report here on optimization of the carbon substrate for improved lipid yield and transcriptional regulation of lipid biosynthetic genes in C. tropicalis. Our study paves the way for further enhancement of lipid production by metabolic engineering in this organism, which has potential to be the lipid feedstock as a cocoa-butter substitute.