The inhibition of alanine dehydrogenase by metal chelates of tetracycline.
نویسنده
چکیده
In a recent, communication (1) we described the purification and properties of a soluble alanine dehydrogenase isolated from cell-free extracts of the H37Ra strain of Mycobacterium tuberculosis. This enzyme catalyzes the diphosphopyridine nucleotidelinked oxidative deamination of L-alanine to pyruvate. During the study of this enzyme it was observed that Terramycinl inhibits the oxidative reaction but not, the reverse reductive step. Furthermore only crude or partially purified enzyme preparations show this inhibition; purified preparations are insensitive to the antibiotic. The inhibition is moderate but reproducible. Investigation of these findings has lead to the conclusion that Terramycin inhibits the alanine dehydrogenase only in the form of a metal chelate. Inhibition of enzyme systems by metal chelates of antibiotics has often been proposed as a mechanism of antibiotic action but, little or no evidence has been presented on behalf of this proposal (2).
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عنوان ژورنال:
- The Journal of biological chemistry
دوره 235 شماره
صفحات -
تاریخ انتشار 1960