title: The five cysteine residues located in the active site region of bovine aspartyl (asparaginyl) beta-hydroxylase are not essential for catalysis.
abstract: In previous chemical modification studies on bovine aspartyl (asparaginyl) beta-hydroxylase, cysteines were implicated as critical catalytic residues. Using site-directed mutagenesis, the five cysteine residues located in a highly conserved region of the enzyme identified as the active site were individually mutated to alanine. Substitutions at cysteine 637, 644, 656, 681, and 696 resulted in active mutant enzymes indicating that these residues are not required for catalysis.
authors.affiliation: Merck Research Laboratories, West Point, PA 19486, USA.
authors.forename: K
authors.initials: K
authors.lastname: McGinnis
authors.forename: G M
authors.initials: GM
authors.lastname: Ku
authors.forename: J
authors.initials: J
authors.lastname: Fu
authors.forename: A M
authors.initials: AM
authors.lastname: Stern
authors.forename: P A
authors.initials: PA
authors.lastname: Friedman
mesh_terms: D000409:Alanine / Q000235:genetics; D000818:Animals; D001665:Binding Sites / Q000235:genetics; D002384:Catalysis; D002417:Cattle; D003545:Cysteine / Q000737:chemistry*; D006899:Mixed Function Oxygenases / Q000378:metabolism*; D016297:Mutagenesis, Site-Directed / Q000235:genetics; D011994:Recombinant Proteins / Q000378:metabolism
chemical_list: D011994:Recombinant Proteins; D006899:Mixed Function Oxygenases; C058291:aspartic acid 2-oxoglutarate-dependent dioxygenase; D003545:Cysteine; D000409:Alanine