Abstract: | 1. Alanine inhibits rabbit muscle AMP-deaminase while aspartate, histidine and glutamate are ineffective. 2. The degree and type of inhibition of AMP-deaminase by alanine depend on pH; at pH 6.5 alanine behaves like an allosteric effector exerting a negative heterotropic effect. At pH 7.0 the inhibition is non-competitive, Ki being as high as 19 mM. 3. The probable significance of the effect of alanine on AMP-deaminase in muscle metabolism is discussed. |