PMID: 2911584

Authors:

Navia MA, McKeever BM, Springer JP, Lin TY, Williams HR, Fluder EM, Dorn CP, Hoogsteen K

Title:

Structure of human neutrophil elastase in complex with a peptide chloromethyl ketone inhibitor at 1.84-A resolution.

Journal:

Proc Natl Acad Sci U S A. 1989 Jan;86(1):7-11.

Abstract:

Human neutrophil elastase (HNE) has been implicated as a major contributor to tissue destruction in various disease states, including emphysema. The structure of HNE, at neutral pH, in complex with methoxysuccinyl-Ala-Ala-Pro-Ala chloromethyl ketone (MSACK), has been solved and refined to an R factor of 16.4% at 1.84-A resolution. Results are consistent with the currently accepted mechanism of peptide chloromethyl ketone inhibition of serine proteases, in that MSACK cross-links the catalytic residues His-57 and Ser-195. The structure of the HNE-MSACK complex is compared with that of porcine pancreatic elastase in complex with L-647,957, a beta-lactam inhibitor of both elastases. The distribution of positively charged residues on HNE is highly asymmetric and may play a role in its specific association with the underlying negatively charged proteoglycan matrix of the neutrophil granules in which the enzyme is stored.