Isolation and characterization of a cDNA encoding Arabidopsis thaliana 3-hydroxy-3-methylglutaryl-coenzyme A synthase.
An 1.7-kb Arabidopsis thaliana (At) cDNA was isolated by complementation of a bap1 mutation affecting the transport of branched-chain amino acids (aa) in the yeast Saccharomyces cerevisiae. The determination of the nucleotide (nt) sequence revealed an open reading frame of 1383 nt which may encode a protein of 461 aa with a predicted molecular mass of 51,038 Da. The deduced aa sequence exhibited strong similarities with mammalian 3-hydroxy-3-methylglutaryl-coenzyme A synthase (HMGS) sequences. Although former biochemical studies have suggested that acetoacetyl-coenzyme A thiolase (AACT) and HMGS activities were carried by a single protein in plants, complementation studies and measurements of enzymatic activities clearly showed that the At HMGS is devoid of AACT activity.
Montamat
F
F
Laboratorie de Physiologie et Biochimie Végétales, URA CNRS 574, Université de Poitiers, France.
Guilloton
M
M
Karst
F
F
Delrot
S
S
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D017343:Genes, Plant; D005816:Genetic Complementation Test; D006904:Hydroxymethylglutaryl-CoA Synthase / Q000235:genetics*; D008969:Molecular Sequence Data; D012441:Saccharomyces cerevisiae / Q000235:genetics
D018076:DNA, Complementary; D006904:Hydroxymethylglutaryl-CoA Synthase