Abstract
When formamidase purified from rat liver was applied on formylkynurenine, o-formylaminoacetophenone, or formylanthranilic acid as a substrate, respective product, kynurenine showed a non-antagonistic type of inhibition, and o-aminoacetophenone and anthranilic acid a mixed-type inhibition. In order to clarify the relationship between the chemical structure of these inhibitors and their inhibitive action, examinations were made on the mode of inhibition and inhibition ratio of compounds structurally related to kynurenine, o-aminoacetophenone, and anthranilic acid, and their position isomers. From the inhibition ratio and inhibition type of these compounds, the inhibitive ratio was markedly low in compounds having a carboxyl or carbonyl group in the benzene ring, and such compounds showed antagonistic or approximately antagonistic type of inhibition. In contrast, introduction of an amino group into the position ortho to resulted in a marked increase in inhibition with changes in the type of inhibition.
