The 1.75 A crystal structure of acetyl-CoA synthetase bound to adenosine-5'-propylphosphate and coenzyme A.
Acetyl-coenzyme A synthetase catalyzes the two-step synthesis of acetyl-CoA from acetate, ATP, and CoA and belongs to a family of adenylate-forming enzymes that generate an acyl-AMP intermediate. This family includes other acyl- and aryl-CoA synthetases, firefly luciferase, and the adenylation domains of the modular nonribosomal peptide synthetases. We have determined the X-ray crystal structure of acetyl-CoA synthetase complexed with adenosine-5'-propylphosphate and CoA. The structure identifies the CoA binding pocket as well as a new conformation for members of this enzyme family in which the approximately 110-residue C-terminal domain exhibits a large rotation compared to structures of peptide synthetase adenylation domains. This domain movement presents a new set of residues to the active site and removes a conserved lysine residue that was previously shown to be important for catalysis of the adenylation half-reaction. Comparison of our structure with kinetic and structural data of closely related enzymes suggests that the members of the adenylate-forming family of enzymes may adopt two different orientations to catalyze the two half-reactions. Additionally, we provide a structural explanation for the recently shown control of enzyme activity by acetylation of an active site lysine.
Gulick
Andrew M
AM
Hauptman-Woodward Medical Research Institute, Buffalo, New York 14203-1149, USA. gulick@hwi.buffalo.edu
Starai
Vincent J
VJ
Horswill
Alexander R
AR
Homick
Kristen M
KM
Escalante-Semerena
Jorge C
JC
D000106:Acetate-CoA Ligase / Q000737:chemistry* / Q000302:isolation & purification; D000107:Acetylation; D000214:Acyl Coenzyme A / Q000737:chemistry; D000249:Adenosine Monophosphate / Q000737:chemistry*; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000302:isolation & purification; D001665:Binding Sites; D001667:Binding, Competitive; D003065:Coenzyme A / Q000737:chemistry*; D003066:Coenzyme A Ligases / Q000037:antagonists & inhibitors / Q000737:chemistry; D003460:Crystallization; D018360:Crystallography, X-Ray; D004791:Enzyme Inhibitors / Q000737:chemistry; D008969:Molecular Sequence Data; D011487:Protein Conformation; D019779:Salmonella enterica / Q000201:enzymology
D000214:Acyl Coenzyme A; D001426:Bacterial Proteins; D004791:Enzyme Inhibitors; C009061:propionyl-coenzyme A; D000249:Adenosine Monophosphate; D003066:Coenzyme A Ligases; D000106:Acetate-CoA Ligase; C068072:propionate - CoA ligase; D003065:Coenzyme A