The temperature-dependent catalytic activity of rat liver 3-hydroxy-3 -methylglutaryl coenzyme A reductase (HMG-CoA reductase) displays the nonlinear Arrhenius behavior characteristic of many membrane-bound enzymes. A two-conformer equilibrium model has been developed to characterize this behavior. In the model, HMG-CoA reductase undergoes a conformational change from a low specific activity to a high specific activity form. This conformation change is apparently driven by a temperature-dependent phase transition of the membrane lipids. It has been found that this model accurately describes the data from diets including rat chow, low-fat, high-carbohydrate, and diets supplemented with fat, cholesterol or cholestyramine. The effects characterized by the model are consistent with the regulation of HMG-CoA reductase by enzyme-lipid interactions.
| Identifer | oai:union.ndltd.org:unt.edu/info:ark/67531/metadc504046 |
| Date | 05 1900 |
| Creators | Smith, Vana L. |
| Contributors | Thompson, Richard E., Norton, S. J., Russell, Benny |
| Publisher | North Texas State University |
| Source Sets | University of North Texas |
| Language | English |
| Detected Language | English |
| Type | Thesis or Dissertation |
| Format | iii, 84 leaves: ill., Text |
| Rights | Public, Smith, Vana L., Copyright, Copyright is held by the author, unless otherwise noted. All rights reserved. |
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