Inhibitory Spectrum of Talopeptin (MKI), a Specific Inhibitor of Thermolysin

抄録

Talopeptin (N-(6-deoxy-α-L-talopyranosyloxyphospho)-L-leucyl-L-tryptophan), a specific inhibitor for thermolysin and some other endo-type metalloproteases, does not inhibit superoxide dismutase, alkaline phosphatase, or carbonic anhydrase, which are Zn(II)-enzymes, in the inhibitor concentration of the order of 10^-4M. Although the enzyme activity of carboxypeptidase A, a Zn(II)-containing exo-type metalloprotease, is slightly reduced by the addition of talopeptin, the inhibition is not significant at the 10% leveljudged by Student's t test. On the other hand, talopeptin seemed to act as an inhibitor for all dehydrogenases examined, most of which do not contain Zn(II), at the inhibitor concentration studied (around 10^-4m). It is possible that the phosphite group of talopeptin binds to the same site on the dehydrogenase as the one for the phosphate group of the coenzyme.