PMID: 8673607

Authors:

Fitzgerald MM, Musah RA, McRee DE, Goodin DB

Title:

A ligand-gated, hinged loop rearrangement opens a channel to a buried artificial protein cavity.

Journal:

Nat Struct Biol. 1996 Jul;3(7):626-31.

Abstract:

Conformational changes that gate the access of substrates or ligands to an active site are important features of enzyme function. In this report, we describe an unusual example of a structural rearrangement near a buried artificial cavity in cytochrome c peroxidase that occurs on binding protonated benzimidazole. A hinged main-chain rotation at two residues (Pro 190 and Asn 195) results in a surface loop rearrangement that opens a large solvent-accessible channel for the entry of ligands to an otherwise inaccessible binding site. The trapping of this alternate conformational state provides a unique view of the extent to which protein dynamics can allow small molecule penetration into buried protein cavities.