Acyl-coenzyme A carboxylase of the free-living nematode Turbatrix aceti. 1. Its isolation and molecular characteristics.

A biotin containing enzyme which carboxylates acetyl-CoA has been isolated from the nematode Turbatrix aceti and purified to homogeneity as judged by the criteria of polyacrylamide gel electrophoresis and ultracentrifugation. The enzyme has a sedimentation coefficient of 18.0 S and a molecular weight of 667 000. It is composed of four protomers having a molecular weight of 140 000 each. Each protomer, in turn, consists of two distinct polypeptide chains (molecular weights 82 000 and 58 000) and one biotinyl prosthetic group which is linked to the 82 000 peptide. The amino acid composition of the nematode carboxylase has also been determined.