Further Studies on the Properties of the Pigeon Liver Fatty Acid Synthetase

Purified pigeon liver fatty acid synthetase was stabilized for at least 4 days in the presence of the reducing agent dithiothreitol. After reduction this purified enzyme system migrated as a single band on starch gel electrophoresis, and it retained the capacity to synthesize fatty acids when eluted from the gel. Molecular weight determination of the stabilized fatty acid synthetase complex by equilibrium centrifugation yielded a value (4.5 x 105) slightly lower than previously reported. NH2-terminal amino acid analysis and electrophoresis of acetic acid-phenol-urea-dissociated fatty acid synthetase on polyacrylamide gel indicated the presence of 5 to 8 peptides in the complex.