Macromolecular crowding effects on the kinetics of opposing reactions catalyzed by alcohol dehydrogenase.

ABSTRACT: In order to better understand how the complex, densely packed, heterogeneous milieu of a cell influences enzyme kinetics, we exposed opposing reactions catalyzed by yeast alcohol dehydrogenase (YADH) to both synthetic and protein crowders ranging from 10 to 550 kDa. The results reveal that the effects from macromolecular crowding depend on the direction of the reaction. The presence of the synthetic polymers, Ficoll and dextran, decrease V_max and K_m for ethanol oxidation. In contrast, these crowders have little effect or even increase these kinetic parameters for acetaldehyde reduction. This increase in V_max is likely due to excluded volume effects, which are partially counteracted by viscosity hindering release of the NAD⁺ product. Macromolecula

SUBMITTER: Wilcox XE 

PROVIDER: S-EPMC7905371 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature