1aa4
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SPECIFICITY OF LIGAND BINDING IN A BURIED POLAR CAVITY OF CYTOCHROME C PEROXIDASE
OverviewOverview
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.
About this StructureAbout this Structure
1AA4 is a [Single protein] structure of sequence from [Saccharomyces cerevisiae] with HEM as [ligand]. Active as [Cytochrome-c peroxidase], with EC number [1.11.1.5]. Structure known Active Site: ACT. Full crystallographic information is available from [OCA].
ReferenceReference
A ligand-gated, hinged loop rearrangement opens a channel to a buried artificial protein cavity., Fitzgerald MM, Musah RA, McRee DE, Goodin DB, Nat Struct Biol. 1996 Jul;3(7):626-31. PMID:8673607
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