Abstract
It was observed that the crude thiaminase II of Bacillus aneurinolyticus could not accelerate the decomposition of cocarboxylase, whereas the crude thiaminase I of B. thiaminolyticus and shell-fish could accelerate it directly. Although pyrimidine compound and thiazole phosphate were detected on a paper strip of paper partition chromatography as decomposition products of cocarboxylase by the crude thiaminase I of B. thiaminolyticus, it was recognized that pyrimidine compound and free thiazole were the end products in the case of crude thiaminase I of shell-fish. However, it was found that thiaminase I of shell-fish also destroyed cocarboxylase directly into pyrimidine compound and thiazole phosphate when NaF or Na_2MoO_4 was used as a phosphatase inhibitor in the reaction mixture of cocarboxylase and the crude thiaminase solution.
