The location of the catalytic site of the membrane-bound respiratory fumarate reductase of Escherichia coli was investigated using mutants and inhibitors of dicarboxylic acid transport. Comparison of apparent Km and Vmax values for fumarate in intact cells and in inverted membrane vesicles showed that externally added fumarate was required to be transported across the cytoplasmic membrane prior to reduction. The catalytic site of fumarate reductase must therefore be located on the cytoplasmic face of the membrane.
GutowskiS.J.,
RosenbergH.1976; Effects of dicyclohexylcarbodiimide on proton translocation coupled to fumarate reduction in anaerobically grown cells of Escherichia coti K12. Biochemical Journal 160:813–816
GutowskiS.J.,
RosenbergH.1977; Proton translocation coupled to electron flow from endogenous substrates to fumarate in anaerobically grown Escherichia coti K12. Biochemical Journal 164:265–267
JonesR.W.,
GarlandP.B.1977; Sites and specificity of the reaction of bipyridylium com-pounds with anaerobic respiratory enzymes of Escherichia colt. Effects of permeability barriers imposed by the cytoplasmic membrane. Biochemical Journal 164:199–211
LemireB.D.,
RobinsonJ.J.,
BradleyR.D.,
ScarabaD.G.,
WeinerJ.H.1983; Structure of fumarate reductase on the cytoplasmic membrane of Escherichia coli. Journal of Bacteriology 155:391–397
Van der plasJ.,
HellingwerfK.J.,
SeijenH.G.,
GuestJ.R.,
WeinerJ.H.,
KoningsW.N.1983; Identification and localisation of enzymes on the fumarate reductase and nitrate respiratory systems of Escherichia coli by crossed immunoelectrophoresis. Journal of Bacteriology 153:1027–1037