The purification of thiaminase I produced by Bacillus thiaminolyticus.

It is well known that thiaminase which destroys thiamine is distributed in the viscera of fresh-water fish, shellfish and ferns, and produced by some microorganisms. Recently, thiaminase ‡U, which catalyzes the hydrolysis of thiamine, was purified and crystallized by Kimura et al. (1) and Ikehata (2). The purification of thiaminase ‡T, which catalyzes a transfer reaction in the presence of a basic substance, was attempted by Reddy et al. (3), Agren (4), Kuratani (5), Nose et al. (6), and Yokota without success. The purification of the enzyme producd by Bacillus thiaminolyticus Matsu kawa et Misawa has been achieved by the application of ion exchange chro matography and zone electrophoresis, and the pure thiaminase preparation obtained. The present paper deals with the method of purification and some of the properties of the enzyme.