1elg
From Proteopedia
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NATURE OF THE INACTIVATION OF ELASTASE BY N-PEPTIDYL-O-AROYL HYDROXYLAMINE AS A FUNCTION OF PH
Overview
The mechanism of inactivation of porcine pancreatic elastase (PPE) by N-peptidyl-O-aroylhydroxylamine was studied by X-ray crystallography. The inactivator forms a stable complex with the enzyme by means of a covalent attachment to the active site Ser 203(195) O gamma. The nature of the complex is, however, different depending on the pH at which the inactivation reaction occurs. At pH 5, the complex formed is a hydroxylamine derivative of Ser 203(195) in which the O gamma of serine is the oxygen of the hydroxylamine derivative. At pH 7.5, the complex formed is a carbamate derivative at Ser 203(195) O gamma. In both types of complexes, the inactivator binds in the S' subsites of the enzyme instead of forming the usual antiparallel beta-sheet with the S subsites. The implication for the mechanism of inactivation at different pHs is discussed.
About this Structure
1ELG is a Single protein structure of sequence from Sus scrofa with and as ligands. Active as Pancreatic elastase, with EC number 3.4.21.36 Full crystallographic information is available from OCA.
Reference
Nature of the inactivation of elastase by N-peptidyl-O-aroyl hydroxylamine as a function of pH., Ding X, Rasmussen BF, Demuth HU, Ringe D, Steinmetz AC, Biochemistry. 1995 Jun 13;34(23):7749-56. PMID:7779821
Page seeded by OCA on Thu Feb 21 12:29:01 2008
