Catalytic plasticity of fatty acid modification enzymes underlying chemical diversity of plant lipids.
Higher plants exhibit extensive diversity in the composition of seed storage fatty acids. This is largely due to the presence of various combinations of double or triple bonds and hydroxyl or epoxy groups, which are synthesized by a family of structurally similar enzymes. As few as four amino acid substitutions can convert an oleate 12-desaturase to a hydroxylase and as few as six result in conversion of a hydroxylase to a desaturase. These results illustrate how catalytic plasticity of these diiron enzymes has contributed to the evolution of the chemical diversity found in higher plants.
Broun
P
P
Carnegie Institution of Washington, Department of Plant Biology, 260 Panama Street, Stanford, CA 94305, USA.
Shanklin
J
J
Whittle
E
E
Somerville
C
C
D019943:Amino Acid Substitution; D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics; D001665:Binding Sites; D002384:Catalysis; D044943:Fatty Acid Desaturases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism*; D005231:Fatty Acids, Unsaturated / Q000378:metabolism*; D017343:Genes, Plant; D006880:Hydroxy Acids / Q000378:metabolism; D006900:Hydroxylation; D019787:Linoleic Acid / Q000378:metabolism; D006899:Mixed Function Oxygenases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016297:Mutagenesis, Site-Directed; D019301:Oleic Acid / Q000378:metabolism; D044925:Oxidoreductases Acting on CH-CH Group Donors; D010940:Plant Proteins; D010944:Plants / Q000201:enzymology* / Q000235:genetics; D030821:Plants, Genetically Modified; D011994:Recombinant Proteins / Q000378:metabolism; D012277:Ricinoleic Acids / Q000378:metabolism
D005227:Fatty Acids; D005231:Fatty Acids, Unsaturated; D006880:Hydroxy Acids; D010940:Plant Proteins; D011994:Recombinant Proteins; D012277:Ricinoleic Acids; D019301:Oleic Acid; C105775:lesquerolic acid; C105774:densipolic acid; D019787:Linoleic Acid; D006899:Mixed Function Oxygenases; C094812:phosphatidylcholine 12-monooxygenase; D044943:Fatty Acid Desaturases; C021904:Phosphatidylcholine desaturase; D044925:Oxidoreductases Acting on CH-CH Group Donors; C030521:ricinoleic acid