M. Wieser et al., Carbon dioxide fixation by reversible pyrrole-2-carboxylate decarboxylase and its application, J MOL CAT B, 11(4-6), 2001, pp. 179-184
Inducible pyrrole-2-carboxylate decarboxylase from Bacillus megaterium PYR3
910 catalyzes the decarboxylation of pyrrole-2-carboxylate to stoichiometri
c amounts of pyrrole and CO2. A unique feature of the homodimeric enzyme is
its requirement for an organic acid such as acetate, propionate, butyrate
or pimelate. A catalytic mechanism including a cofactor function of the org
anic acid was proposed. Due to an equilibrium constant of 0.3-0.4 M, the en
zyme also catalyzes the reverse carboxylation of pyrrole after the addition
of bicarbonate. For the synthesis of pyrrole-2-carboxylate, the reverse re
action was optimized and the equilibrium shifted towards the carboxylate. T
he product yield was 230 mM (25.5 g/l) pyrrole-2-carboxylate from 300 mM py
rrole in a batch reaction and 325 mM (36.1 g/l) from 400 mM pyrrole in a fe
d batch reaction, using both whole cells and the purified enzyme in a pH 8.
0 reaction mixture with bicarbonate saturation of 1.9 M. (C) 2001 Elsevier
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