title: The structure of cat muscle pyruvate kinase.
abstract: The complete amino acid sequence of cat muscle pyruvate kinase has been determined and fitted to the 2.6 A resolution electron density map. Residues in the active site region are highly conserved in the cat muscle, chicken muscle, rat liver and yeast enzymes. The enzyme-bound magnesium, which is essential for activity, interacts with the side chain of glutamate-271 and with two main carbonyl groups. Lysine-269 is the probable acid/base catalyst responsible for the interconversion of pyruvate and enolpyruvate. A possible binding site for the essential monovalent cation is proposed.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D002415:Cats; D002645:Chickens; D008958:Models, Molecular; D009132:Muscles / Q000201:enzymology*; D011487:Protein Conformation; D011770:Pyruvate Kinase / Q000378:metabolism*; D051381:Rats; D012441:Saccharomyces cerevisiae / Q000201:enzymology; D013045:Species Specificity
chemical_list: D011770:Pyruvate Kinase