title: Biochemical characterization of a chloroplast localized fatty acid reductase from Arabidopsis thaliana.
abstract: Primary long-chain fatty alcohols are present in a variety of phyla. In eukaryotes, the production of fatty alcohols is catalyzed by fatty acyl-CoA reductase (FAR) enzymes that convert fatty acyl-CoAs or acyl-ACPs into fatty alcohols. Here, we report on the biochemical properties of a purified plant FAR, Arabidopsis FAR6 (AtFAR6). In vitro assays show that the enzyme preferentially uses 16 carbon acyl-chains as substrates and produces predominantly fatty alcohols. Free fatty acids and fatty aldehyde intermediates can be released from the enzyme, in particular with suboptimal chain lengths and concentrations of the substrates. Both acyl-CoA and acyl-ACP could serve as substrates. Transient expression experiments in Nicotiana tabacum showed that AtFAR6 is a chloroplast localized FAR. In addition, expression of full length AtFAR6 in Nicotiana benthamiana leaves resulted in the production of C16:0-alcohol within this organelle. Finally, a GUS reporter gene fusion with the AtFAR6 promoter showed that the AtFAR6 gene is expressed in various tissues of the plant with a distinct pattern compared to that of other Arabidopsis FARs, suggesting specialized functions in planta.
authors.affiliation: Department of Plant Breeding and Biotechnology, Swedish University of Agricultural Sciences, Alnarp, Sweden. thuy.doan@slu.se
authors.forename: Thuy T P
authors.initials: TT
authors.lastname: Doan
authors.forename: Frédéric
authors.initials: F
authors.lastname: Domergue
authors.forename: Ashley E
authors.initials: AE
authors.lastname: Fournier
authors.forename: Sollapura J
authors.initials: SJ
authors.lastname: Vishwanath
authors.forename: Owen
authors.initials: O
authors.lastname: Rowland
authors.forename: Patrick
authors.initials: P
authors.lastname: Moreau
authors.forename: Craig C
authors.initials: CC
authors.lastname: Wood
authors.forename: Anders S
authors.initials: AS
authors.lastname: Carlsson
authors.forename: Mats
authors.initials: M
authors.lastname: Hamberg
authors.forename: Per
authors.initials: P
authors.lastname: Hofvander
mesh_terms: D000214:Acyl Coenzyme A / Q000235:genetics / Q000378:metabolism; D000445:Aldehyde Oxidoreductases / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D060365:Chloroplast Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D002736:Chloroplasts / Q000201:enzymology* / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D018506:Gene Expression Regulation, Plant / Q000502:physiology*; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D013379:Substrate Specificity / Q000502:physiology; D014026:Nicotiana / Q000201:enzymology / Q000235:genetics
chemical_list: D000214:Acyl Coenzyme A; D029681:Arabidopsis Proteins; D060365:Chloroplast Proteins; D011994:Recombinant Proteins; D000445:Aldehyde Oxidoreductases; C027902:fatty acid reductase