Sundqvist K E, Hiltunen J K, Hassinen I E
Department of Medical Biochemistry, University of Oulu, Finland.
Biochem J. 1989 Feb 1;257(3):913-6. doi: 10.1042/bj2570913.
Pyruvate carboxylation in the isolated perfused rat heart was studied under steady-state conditions. A biotin deficiency resulting in a 90% decrease in myocardial pyruvate carboxylase left the pyruvate carboxylation rate unchanged. Pyruvate carboxylation in heart muscle must therefore take place by means of an enzyme which does not contain biotin. The kinetic properties and mass-action ratio of the NADP-linked malic enzyme in heart muscle can be taken as circumstantial evidence in favour of the role of malic enzyme in pyruvate carboxylation in myocardium.
在稳态条件下研究了分离的灌注大鼠心脏中的丙酮酸羧化作用。生物素缺乏导致心肌丙酮酸羧化酶减少90%，但丙酮酸羧化速率未变。因此，心肌中的丙酮酸羧化作用必定是通过一种不含生物素的酶来进行的。心肌中与NADP相关的苹果酸酶的动力学特性和质量作用比可作为支持苹果酸酶在心肌丙酮酸羧化中作用的间接证据。
