Studies on the Activity of Acetyl Coenzyme A Carboxylase in Human Adipose Tissue[*]

Abstract

The properties of acetyl coenzyme A carboxylase (AcCoAC) in extracts from human and rat adipose tissue were studied and the activity of the enzyme in these two species was compared under different experimental conditions. Extracts from both tissues were able to synthesize malonyl coenzyme A from acetyl coenzyme A in the presence of C¹⁴-bicarbonate and different co-factors as demonstrated by isolation of C¹⁴-malonyl coenzyme A. AcCoA-C was 4 to 5-fold more active in rat than in human adipose tissue, the co-factor requirements were, however, identical, with the only exception that Mg⁺⁺ was necessary for maximal enzyme activity in human and Man⁺⁺ in rat tissue. The problems imposed by the presence of Cacao-C in human adipose tissue are discussed. AcCoA: Acetyl coenzyme A, AcCoA-C: Acetyl coenzyme A carboxylase, FA: Fatty acid, CCE: Citrate cleavage enzyme

Acetyl Coencyme A Carboxylase - Malonyl Coenzyme A

1 These studies were supported by the Deutsche Forschungsgemeinschaft, Bad Godesberg, Germany