In Escherichia coli and related bacteria, the pflA protein (or act)  is
involved (EC 188.8.131.52) in the activation of pyruvate formate-lyase (gene pflB)
under anaerobic conditions by generation of an organic free radical, using S-adenosylmethionine and reduced flavodoxin as cosubstrates to produce 5'-deoxy-adenosine. A protein highly similar to pflA and termed pflC  is probably
involved in the activation of a second pyruvate format lyase (gene pflD). The
pflA/C proteins belong to a family that also includes phage T4 and Escherichia
coli nrdG which are involved  in the generation of the free radical for the
anaerobic ribonucleoside-triphosphate reductase (gene nrdD or sunY). This
family also includes:
Escherichia coli hypothetical protein yjjW.
Haemophilus influenzae hypothetical protein HI0520.
Methanococcus jannaschii hypothetical protein MJ0021.
All these proteins possess, in their N-terminal section, a highly conserved
region which contains three clustered cysteines which are involved in the
binding of a 4Fe4S iron-sulfur cluster . We use this region as a signature
December 2004 / Pattern and text revised.
PROSITE method (with tools and information) covered by this documentation:
Roedel W. Plaga W. Frank R. Knappe J.
Eur. J. Biochem. 177:153-158(1988).
Reizer J. Reizer A. Saier M.H. Jr.
Novel phosphotransferase system genes revealed by bacterial genome analysis--a gene cluster encoding a unique Enzyme I and the proteins of a fructose-like permease system.
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