title: Ketoacyl synthase domain is a major determinant for fatty acyl chain length in Saccharomyces cerevisiae.
abstract: Yeast fatty acid synthase (Fas) comprises two subunits, α6 and β6, encoded by FAS2 and FAS1, respectively. To determine features of yeast Fas that control fatty acyl chain length, chimeric genes were constructed by combining FAS sequences from Saccharomyces cerevisiae (ScFAS) and Hansenula polymorpha (HpFAS), which mostly produces C16 and C18 fatty acids, respectively. The C16/C18 ratios decreased from 2.2 ± 0.1 in wild-type S. cerevisiae to 1.0 ± 0.1, 0.5 ± 0.2 and 0.8 ± 0.1 by replacement of ScFAS1, ScFAS2 and ScFAS1 ScFAS2 with HpFAS1, HpFAS2 and HpFAS1 HpFAS2, respectively, suggesting that the α, but not β subunits play a major role in determining fatty acyl chain length. Replacement of phosphopantetheinyl transferase (PPT) domain with the equivalent region from HpFAS2 did not affect C16/C18 ratio. Chimeric Fas2 containing half N-terminal ScFas2 and half C-terminal HpFas2 carrying H. polymorpha ketoacyl synthase (KS) and PPT gave a remarkable decrease in C16/C18 ratio (0.6 ± 0.1), indicating that KS plays a major role in determining chain length.
authors.affiliation: Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita-shi, Osaka, 565-0871, Japan.
authors.forename: Juthaporn
authors.initials: J
authors.lastname: Sangwallek
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Kaneko
authors.forename: Minetaka
authors.initials: M
authors.lastname: Sugiyama
authors.forename: Hisayo
authors.initials: H
authors.lastname: Ono
authors.forename: Takeshi
authors.initials: T
authors.lastname: Bamba
authors.forename: Eiichiro
authors.initials: E
authors.lastname: Fukusaki
authors.forename: Satoshi
authors.initials: S
authors.lastname: Harashima
mesh_terms: D000891:Anti-Infective Agents, Local / Q000494:pharmacology; D001483:Base Sequence; D000431:Ethanol / Q000494:pharmacology; D064429:Fatty Acid Synthases / Q000235:genetics; D005227:Fatty Acids / Q000737:chemistry* / Q000235:genetics; D006358:Hot Temperature; D010843:Pichia / Q000201:enzymology / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics* / Q000254:growth & development; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics
chemical_list: D000891:Anti-Infective Agents, Local; D005227:Fatty Acids; D029701:Saccharomyces cerevisiae Proteins; D000431:Ethanol; D064429:Fatty Acid Synthases; C526685:FAS1 protein, S cerevisiae; C577477:FAS2 protein, S cerevisiae