Interactions of macromolecular crowding agents and cosolutes with small-molecule substrates: effect on horseradish peroxidase activity with two different substrates.

ABSTRACT: The importance of solution composition on enzymatic reactions is increasingly appreciated, particularly with respect to macromolecular cosolutes. Macromolecular crowding and its effect on enzymatic reactions has been studied for several enzymes and is often understood in terms of changes to enzyme conformation. Comparatively little attention has been paid to the chemical properties of small-molecule substrates for enzyme reactions in crowded solution. In this article, we studied the reaction of horseradish peroxidase (HRP) with two small-molecule substrates that differ in their hydrophobicity. Crowding agents and cosolutes had quite different effects on HRP activity when the substrate used was 3,3',5,5'-tetramethylbenzidine (TMB, which is hydrophobic) as compared to o-phenylenediamine (OPD

SUBMITTER: Aumiller WM 

PROVIDER: S-EPMC4161143 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature