Structure-activity analysis of base and enzyme-catalyzed 4-hydroxybenzoyl coenzyme A hydrolysis

Bioorg Chem. 2007 Feb;35(1):1-10. doi: 10.1016/j.bioorg.2006.07.002. Epub 2006 Sep 7.

Abstract

In this study, the second-order rate constant k2 of base-catalyzed hydrolysis and the values of kcat, Km and kcat/Km of wild-type Pseudomonas sp. CBS3 4-hydroxybenzoyl coenzyme A (4-HBA-CoA) thioesterase-catalyzed hydrolysis of 4-HBA-CoA and its para-substituted analogs were measured. For the base-catalyzed hydrolysis, the plot of logk2 vs the sigma value of the para-substituents was linear with a slope (rho) of 1.5. In the case of the enzyme-catalyzed hydrolysis, the kcat/Km values measured for the para-substituted analogs defined substrate specificity. Asp32 was shown to play a key role in substrate recognition, and in particular, in the discrimination between the targeted substrate and other cellular benzoyl-CoA thioesters.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Acyl Coenzyme A / chemistry*
  • Asparagine / chemistry
  • Asparagine / genetics
  • Catalysis
  • Catalytic Domain
  • Hydrogen Bonding
  • Hydrolysis
  • Kinetics
  • Models, Chemical
  • Molecular Structure
  • Mutagenesis, Site-Directed
  • Recombinant Proteins / chemistry
  • Structure-Activity Relationship
  • Substrate Specificity
  • Thiolester Hydrolases / chemistry*
  • Thiolester Hydrolases / genetics

Substances

  • Acyl Coenzyme A
  • Recombinant Proteins
  • 4-hydroxybenzoyl-coenzyme A
  • Asparagine
  • 4-hydroxybenzoyl-CoA hydrolase
  • Thiolester Hydrolases