JBC, Vol. 252, Issue 8, 2657-2661, Apr, 1977
Evidence for separate enzymes of pyruvate decarboxylation and pyruvate synthesis in soluble extracts of Clostridium pasteurianum
R. S. Bush and F. D. Sauer
Additional evidence to that already presented (Sauer, F. D., Bush, R. S.,
and Stevenson, I. L. (1976) Biochim. Biophys. Acta 445, 518-520) suggests
that pyruvate-ferredoxin oxidoreductase isolated from Clostridium
pasteurianum consists of two separate enzymes: (a) pyruvate lyase, which
catalyzes the CoA and electron acceptor-dependent decarboxylation of
pyruvate, and (b) pyruvate synthase, which catalyzes the reduced
ferredoxin-dependent carboxylation of acetyl-CoA to pyruvate. The enzymes
separated on Sephadex G-200 and with acrylamide gel electrophoresis but
complete separation of one enzyme free of the other was not achieved.
Extensive purification procedures were not used because both enzymes are
unstable. The results confirm published reports that pyruvate lyase
contains thiamin and a chromophore which participates in electron transfer.
Pyruvate synthase, however, did not appear to be a thiamin enzyme and there
was no evidence to indicate participation of an enzyme chromophore in the
pyruvate synthase reaction.