title: Substrate specificity and regioselectivity of delta12 and omega3 fatty acid desaturases from Saccharomyces kluyveri.
abstract: Delta12 and omega3 fatty acid desaturases are key enzymes in the synthesis of polyunsaturated fatty acids (PUFAs), which are important constituents of membrane glycerolipids and also precursors to signaling molecules in many organisms. In this study, we determined the substrate specificity and regioselectivity of the Delta12 and omega3 fatty acid desaturases from Saccharomyces kluyveri (Sk-FAD2 and Sk-FAD3). Based on heterologous expression in Saccharomyces cerevisiae, it was found that Sk-FAD2 converted C16-20 monounsaturated fatty acids to diunsaturated fatty acids by the introduction of a second double bond at the nu+3 position, while Sk-FAD3 recognized the omega3 position of C18 and C20. Furthermore, fatty acid analysis of major phospholipids suggested that Sk-FAD2 and Sk-FAD3 have no strong substrate specificity toward the lipid polar head group or the sn-positions of fatty acyl groups in phospholipids.
authors.affiliation: Department of Life Science, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama, Kanagawa, Japan. toura@bio.titech.ac.jp
authors.forename: Takahiro
authors.initials: T
authors.lastname: Oura
authors.forename: Susumu
authors.initials: S
authors.lastname: Kajiwara
mesh_terms: D044943:Fatty Acid Desaturases / Q000378:metabolism*; D005227:Fatty Acids / Q000737:chemistry / Q000378:metabolism; D015870:Gene Expression; D010743:Phospholipids / Q000737:chemistry / Q000378:metabolism; D012440:Saccharomyces / Q000201:enzymology*; D012441:Saccharomyces cerevisiae / Q000235:genetics; D013237:Stereoisomerism; D013379:Substrate Specificity
chemical_list: D005227:Fatty Acids; D010743:Phospholipids; D044943:Fatty Acid Desaturases; C040448:delta-12 fatty acid desaturase; C078565:omega-3 fatty acid desaturase