Abstract
1. 2-methyl-4-amino-5-aminomethylpyrimidine inhibits brain glutamic decarboxylase. It also has an inhibitory effect on bacterial tyrosine decarboxylase.
2. The restoration of the glutamic decarboxylase inhibition by PAL phosphate differs according to whether the 2-methyl-4-amino-5-aminomethylpyrimidine comes in contact with the enzyme before or simultaneously with the substrate. Restoration takes place in the case of the latter but not in the former.
3. An inhibitory effect is also observed against brain ABA-KGA transaminase but there is no difference whether the contact is before or simultaneous.
4. This inhibition is overcome by PAL phosphate.
5. 2-methyl-4-amino-5-aminomethylpyrimidine inhibits brain PAL kinase. An apparent enhancement of activity was observed, however, in the case of PAL kinase purified from brewer's yeast.
