title: Targeted mutagenesis of a fatty acid Delta6-desaturase from Mucor rouxii: role of amino acid residues adjacent to histidine-rich motif II.
abstract: The amino acid residues serine at position 213 (S213) and lysine at position 218 (K218), which are present in close proximity to the histidine-rich motif II of Mucor rouxii fatty acid Delta(6)-desaturase isoform II, were targeted for studying structure-function relationships using site-directed mutagenesis. The mutants were functionally characterized in a heterologous host, Saccharomyces cerevisiae. Substrate specificity and preference studies revealed that S213 and K218 are involved in substrate recognition. K218 plays a role in substrate preference by involvement in the binding of substrates, particularly C15-C18 monoene fatty acids. Modification of the M. rouxii Delta(6)-desaturase therefore has potential in specifically altering substrate utilization for production of desired fatty acids.
authors.affiliation: School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Bangkuntien, Bangkok 10150, Thailand.
authors.forename: Sutthicha
authors.initials: S
authors.lastname: Na-Ranong
authors.forename: Kobkul
authors.initials: K
authors.lastname: Laoteng
authors.forename: Prasat
authors.initials: P
authors.lastname: Kittakoop
authors.forename: Morakot
authors.initials: M
authors.lastname: Tanticharoen
authors.forename: Supapon
authors.initials: S
authors.lastname: Cheevadhanarak
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D003198:Computer Simulation; D004789:Enzyme Activation; D005227:Fatty Acids / Q000378:metabolism*; D018390:Gene Targeting; D006639:Histidine / Q000737:chemistry / Q000378:metabolism; D050602:Linoleoyl-CoA Desaturase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009089:Mucor / Q000201:enzymology* / Q000235:genetics; D016297:Mutagenesis, Site-Directed; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship; D013379:Substrate Specificity
chemical_list: D005227:Fatty Acids; D011994:Recombinant Proteins; D006639:Histidine; D050602:Linoleoyl-CoA Desaturase