ピルビン酸の脱炭酸反応(I)パン酵母およびビール酵母Pyruvate decarboxylaseの精製と性質

概要

論文の詳細を見る
Baker's or brewer's yeast pyruvate decarboxylase (EC 4.1.1.1) was purified and separated from the cofactors according to the procedures of Ullrich, Wittof, Gubler^<4)> and Morey, Juni.^<6)> Both of enzymes showed maximum activities at pH 6.2 in the presence of TPP and divalent metal ions. Baker's yeast apo-pyruvate decarboxylase was activated by Mn^<2+>, Mg^<2+>, Ca^<2+>, in the ratios of 4 : 2 : 1 while brewer's yeast apoenzyme was in those of 9 : 3 : 1. Mg^<2+>, Ca^<2+> bound to 1 mole of enzyme was found to be about 0.8 moles. The activities of 1 mole enzyme was almost completely lost in the presence of 2 or 5 moles of PCMB or BrCN respectively and approximately 40% of its activities was lost with 5 moles of DTNB. The formation of CO_2,CH_3CHO and acetoin were all inhibited with PCMB to the same extent and the interaction between enzyme bound TPP and PCMB seems to be responsible for the above inhibitions.
日本ビタミン学会の論文
1972-01-25