Souza BS, Mora JR, Wanderlind EH, Clementin RM, Gesser JC, Fiedler HD, Nome F, Menger FM. Transforming a Stable Amide into a Highly Reactive One: Capturing the Essence of Enzymatic Catalysis.
Angew Chem Int Ed Engl 2017;
56:5345-5348. [PMID:
28378430 DOI:
10.1002/anie.201701306]
[Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 03/10/2017] [Indexed: 11/06/2022]
Abstract
Aspartic proteinases, which include HIV-1 proteinase, function with two aspartate carboxy groups at the active site. This relationship has been modeled in a system possessing an otherwise unactivated amide positioned between two carboxy groups. The model amide is cleaved at an enzyme-like rate that renders the amide nonisolable at 35 °C and pH 4 owing to the joint presence of carboxy and carboxylate groups. A currently advanced theory attributing almost the entire catalytic power of enzymes to electrostatic reorganization is shown to be superfluous when suitable interatomic interactions are present. Our kinetic results are consistent with spatiotemporal concepts where embedding the amide group between two carboxylic moieties in proper geometries, at distances less than the diameter of water, leads to enzyme-like rate enhancements. Space and time are the essence of enzyme catalysis.
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