A novel Delta(12)-fatty acid desaturase gene from methylotrophic yeast Pichia pastoris GS115

摘要

The methylotrophic yeast Pichia pastoris GS115, a widely used strain in production of various heterologous proteins, especially membrane-bound enzymes, can also produce linoleic and linolenic acids, which indicates the existence of membrane-bound All and All-fatty acid desaturases. This paper describes the cloning and functional characterization of a novel Delta(12)-fatty acid desaturase gene from this methylotrophic yeast. The open reading frame of the gene (named Pp-FAD12) is 1263 bp in size and encodes a 420-amino-acid peptide. The deduced Pp-FAD12 protein shows high identity (50-67%) with Delta(12)-fatty acid desaturases from other fungi. It also shows a high identity (57%) with Delta(15)-fatty acid desaturase (named Sk-FAD15) from Saccharomyces kluyveri. Expression of Pp-FAD12 in polyunsaturated fatty acids non-producing yeast Saccharomyces cerevisiae demonstrated that its product converted oleic acid (18:1) to linoleic acid (18:2). This result suggests that Pp-FAD12 encodes a novel Delta(12)-fatty acid desaturase in P. pastoris GS115. This is the first report about the cloning and functional characterization of Delta(12)-fatty acid desaturase gene in methylotrophic yeast.