PDBsum entry 1elf

Complex (hydrolase/inhibitor)

PDB id: 1elf

Contents

Protein chain

240 a.a. *

Ligands

SO4

SO4-BAF

Metals

_CA

Waters ×160

* Residue conservation analysis

PDB id:

1elf

Name:

Complex (hydrolase/inhibitor)

Title:

Nature of the inactivation of elastase by n-peptidyl-o-aroyl hydroxylamine as a function of ph

Structure:

Porcine pancreatic elastase. Chain: a. Engineered: yes

Source:

Sus scrofa. Pig. Organism_taxid: 9823

Resolution:

1.70Å R-factor: 0.180

Authors:

X.Ding,B.Rasmussen,H.-U.Demuth,D.Ringe,A.C.U.Steinmetz

Key ref:

X.Ding et al. (1995). Nature of the inactivation of elastase by N-peptidyl-O-aroyl hydroxylamine as a function of pH. Biochemistry, 34, 7749-7756. PubMed id: 7779821 DOI: 10.1021/bi00023a022

Date:

13-Mar-95 Release date: 10-Jul-95

Protein chain

P00772  (CELA1_PIG) -  Chymotrypsin-like elastase family member 1 from Sus scrofa

Seq: 266 a.a.

Struc: 240 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

• Enzyme class: E.C.3.4.21.36 - pancreatic elastase.
• Reaction: Hydrolysis of proteins, including elastin. Preferential cleavage: Ala-|-Xaa.

DOI no: 10.1021/bi00023a022

Biochemistry 34:7749-7756 (1995)

PubMed id: 7779821

Nature of the inactivation of elastase by N-peptidyl-O-aroyl hydroxylamine as a function of pH.

X.Ding, B.F.Rasmussen, H.U.Demuth, D.Ringe, A.C.Steinmetz.

ABSTRACT

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.