Abstract
We describe the isolation and characterization of a gene (MAELO) that encodes a fatty acid elongase from arachidonic acid-producing fungus Mortierella alpina 1S-4. Although the homologous MAELO gene had already been isolated from M. alpina ATCC 32221, its function had not yet been identified. The MAELO gene from M. alpina 1S-4 was confirmed to encode a fatty acid elongase by its expression in yeast Saccharomyces cerevisiae. Analysis of the fatty acid composition of the yeast transformant revealed the accumulation of 22-, 24-, and 26-carbon saturated fatty acids. On the other hand, RNA interference of the MAELO gene in M. alpina 1S-4 was carried out. The gene-silenced strain obtained on RNA interference exhibited low contents of 20-, 22-, and 24-carbon saturated fatty acids and a high content of stearic acid (18 carbons), compared with those in the wild strain. The enzyme encoded by the MAELO gene was demonstrated to be involved in the biosynthesis of 20-, 22-, and 24-carbon saturated fatty acids in M. alpina 1S-4.
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Acknowledgements
This work was supported in part by Grants-in-Aid for Scientific Research (No. 15658024, to S. S.) from the Ministry of Education, Science, Sports, and Culture, Japan, by the COE for Microbial-Process Development Pioneering Future Production Systems (COE program of the Ministry of Education, Science, Sports, and Culture, Japan to S. S.) and by the Project of the New Energy and Industrial Technology Development Organization, Japan (grant 05A07003d, to E.S.).
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Sakuradani, E., Murata, S., Kanamaru, H. et al. Functional analysis of a fatty acid elongase from arachidonic acid-producing Mortierella alpina 1S-4. Appl Microbiol Biotechnol 81, 497–503 (2008). https://doi.org/10.1007/s00253-008-1675-z
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DOI: https://doi.org/10.1007/s00253-008-1675-z