A multienzyme complex for CO2 fixation.

J S Wolpert; M L Ernst-Fonberg

doi:10.1021/bi00677a001

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A multienzyme complex for CO2 fixation.

J S Wolpert·M L Ernst-Fonberg

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Abstract

Acetyl-coenzyme A carboxylase from Euglena gracilis strain Z was isolated as a component of a multienzyme complex which includes phosphoenolpyruvate carboxylase and malate dehydrogenase. The multienzyme complex was shown to exist in crude extracts and was purified to a homogeneous protein with a molecular weight of 360,000 by gel filtration. The ratio of the activities of the constituent enzymes was acetyl-CoA carboxylase:phosphoenolpyruvate carboxylase:malate dehydrogenase, 1:25:500. The complex is proposed to operate in conjunction with malic enzyme, which is present in Euglena, to facilitate the formation of substrates, malonyl-CoA, and NADPH, for fatty acid biosynthesis. The interaction of the enzymes may represent a means of control of acetyl-CoA carboxylase activity in organisms which do not possess an enzyme subject to allosteric regulation. The acetyl-CoA carboxylase activity from Euglena is unaffected by citrate and isocitrate.

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Acetyl-CoA Carboxylase Animals Carbon Dioxide Euglena gracilis Fatty Acids Ligases Malate Dehydrogenase Molecular Weight Multienzyme Complexes Phosphoenolpyruvate Carboxykinase (GTP)Journal Article Research Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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J S Wolpert, M L Ernst-Fonberg. 1975-03-25. A multienzyme complex for CO2 fixation.. https://doi.org/10.1021/bi00677a001

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