title: Identification and characterization of a novel Delta6-fatty acid desaturase gene from Rhizopus arrhizus.
abstract: A cDNA sequence putatively encoding a Delta(6)-fatty acid desaturase was isolated from Rhizopus arrhizus using reverse transcription polymerase chain reaction and rapid amplification of cDNA ends methods. Sequence analysis indicated that this cDNA sequence had an open reading frame of 1377 bp encoding 458 amino acids of 52 kDa. The deduced amino acid sequence showed high similarity to those of fungal Delta(6)-fatty acid desaturases which comprised the characteristics of membrane-bound desaturases, including three conserved histidine-rich motifs and hydropathy profile. A cytochrome b(5)-like domain was observed at the N-terminus. To elucidate the function of this novel putative desaturase, the coding sequence was expressed heterologously in Saccharomyces cerevisiae strain INVScl. The result demonstrated that the coding product of the sequence exhibited Delta(6)-fatty acid desaturase activity by the accumulation of gamma-linolenic acid.
authors.affiliation: Department of Microbiology, Nankai University, 300071, Tianjin, PR China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
authors.forename: Mingchun
authors.initials: M
authors.lastname: Li
authors.forename: Haiting
authors.initials: H
authors.lastname: Ma
authors.forename: Ying
authors.initials: Y
authors.lastname: Sun
authors.forename: Laijun
authors.initials: L
authors.lastname: Xing
mesh_terms: D000595:Amino Acid Sequence; D002849:Chromatography, Gas; D018076:DNA, Complementary / Q000235:genetics; D044943:Fatty Acid Desaturases / Q000235:genetics*; D005227:Fatty Acids / Q000032:analysis; D005800:Genes, Fungal / Q000235:genetics*; D008055:Lipids / Q000737:chemistry; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010802:Phylogeny; D011994:Recombinant Proteins / Q000235:genetics; D012233:Rhizopus / Q000201:enzymology*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D017965:gamma-Linolenic Acid / Q000032:analysis / Q000096:biosynthesis
chemical_list: D018076:DNA, Complementary; D005227:Fatty Acids; D008055:Lipids; D011994:Recombinant Proteins; D017965:gamma-Linolenic Acid; D044943:Fatty Acid Desaturases