title: Identification and analysis of a gene from Calendula officinalis encoding a fatty acid conjugase.
abstract: Two homologous cDNAs, CoFad2 and CoFac2, were isolated from a Calendula officinalis developing seed by a polymerase chain reaction-based cloning strategy. Both sequences share similarity to FAD2 desaturases and FAD2-related enzymes. In C. officinalis plants CoFad2 was expressed in all tissues tested, whereas CoFac2 expression was specific to developing seeds. Expression of CoFad2 cDNA in yeast (Saccharomyces cerevisiae) indicated it encodes a Delta12 desaturase that introduces a double bond at the 12 position of 16:1(9Z) and 18:1(9Z). Expression of CoFac2 in yeast revealed that the encoded enzyme acts as a fatty acid conjugase converting 18:2(9Z, 12Z) to calendic acid 18:3(8E, 10E, 12Z). The enzyme also has weak activity on the mono-unsaturates 16:1(9Z) and 18:1(9Z) producing compounds with the properties of 8,10 conjugated dienes.
authors.affiliation: Research and Development, Bioriginal Food and Science Corporation, 102 Melville Street, Saskatoon, Saskatchewan, Canada S7J 0R1. xqiu@pbi.nrc.ca
authors.forename: X
authors.initials: X
authors.lastname: Qiu
authors.forename: D W
authors.initials: DW
authors.lastname: Reed
authors.forename: H
authors.initials: H
authors.lastname: Hong
authors.forename: S L
authors.initials: SL
authors.lastname: MacKenzie
authors.forename: P S
authors.initials: PS
authors.lastname: Covello
mesh_terms: D000595:Amino Acid Sequence; D020838:Calendula / Q000145:classification / Q000201:enzymology* / Q000235:genetics*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D044943:Fatty Acid Desaturases / Q000737:chemistry / Q000235:genetics*; D005227:Fatty Acids / Q000032:analysis; D017343:Genes, Plant; D008969:Molecular Sequence Data; D005810:Multigene Family; D010802:Phylogeny; D011994:Recombinant Proteins / Q000737:chemistry; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D018076:DNA, Complementary; D005227:Fatty Acids; D011994:Recombinant Proteins; D044943:Fatty Acid Desaturases