Carbon dioxide fixation by reversible pyrrole-2-carboxylate decarboxylase from Bacillus megaterium PYR2910
Carbon dioxide fixation by reversible pyrrole-2-carboxylate decarboxylase from Bacillus megaterium PYR2910
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DOI：
10.1046/j.1432-1327.1998.2570495.x
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发表时间：
1998-10-01
期刊：
影响因子：
--
通讯作者：
Nagasawa, T
中科院分区：
文献类型：
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作者：
Wieser, M;Fujii, N;Nagasawa, T
巨芽孢杆菌PYR2910的吡咯-2-羧酸脱羧酶达到平衡反应平衡，平衡常数为0.3 ~ 0.4 m。因此，该酶在加入碳酸氢盐后催化吡咯的反羧化反应。对于吡咯-2-羧酸盐的合成，优化了逆反应，使平衡向羧酸盐转移。在pH 8.0、碳酸氢盐饱和1.9 m的条件下，用全细胞和纯化酶进行间歇反应，产率为230 mM （25.5 g/l）吡咯-2-羧酸盐，用400mm吡咯-2-羧酸盐进行间歇反应，产率为325 mM （36.1 g/l）。动力学研究表明，碳酸氢盐是该二氧化碳固定酶使用的反应物质。
Pyrrole-2-carboxylate decarboxylase from Bacillus megaterium PYR2910 attains a balanced reaction equilibrium with an equilibrium constant of 0.3-0.4 M. Therefore, the enzyme catalyzes the reverse carboxylation of pyrrole after addition of bicarbonate. For the synthesis of pyrrole-2-carboxylate, the reverse reaction was optimized and the equilibrium was shifted towards the carboxylate. The product yield was 230 mM (25.5 g/l) pyrrole-2-carboxylate from 300 mM pyrrole in a batch reaction and 325 mM (36.1 g/l) from 400 mM pyrrole in a fed-batch reaction, using both whole cells and the purified enzyme in a pH 8.0 reaction mixture with bicarbonate saturation of 1.9 M. Kinetic studies indicated, that bicarbonate is the reactive species used by this carbon dioxide-fixation enzyme.