Candida lipolytica mutants defective in an acyl-coenzyme A synthetase: isolation and fatty acid metabolism.

AUTOR(ES)

Kamiryo, T

RESUMO

Mutant strains of Candida lipolytica defective in an acyl-CoA synthetase [acid:CoA ligase (AMP-forming); EC 6.2.1.3]were isolated. The mutant strains apparently exhibited no acyl-CoA synthetase activity in vitro and were, in contrast to the wild-type strain, incapable of growing in the presence of exogenous fatty acid when cellular synthesis de novo of fatty acid was blocked. However, the mutant strains grew on either fatty acid or n-alkane as a sole carbon source at rates comparable to that observed for the wild-type strain. Analysis of the fatty acid composition of the lipids from the mutant cells grown on odd-chain-length fatty acid as well as [14C]oleic acid incorporation studies have shown that the mutant cells, unlike the wild-type cells, cannot incorporate exogenous fatty acid as a whole into cellular lipids, but utilize the fatty acid that is synthesized de novo from acetyl-CoA produced by degradation of exogenous fatty acid. This finding indicates the presence of at least two acyl-CoA synthetases that activate long-chain fatty acid. One, designated acyl-CoA synthetase I, which is absent in the mutant strains, is responsible for the production of acyl-CoA to be utilized for the synthesis of cellular lipids. The other acyl-CoA synthetase provides actyl-CoA that is exclusively degraded via beta-oxidation to yield acetyl-CoA.

Documentos Relacionados

• Arabidopsis Contains Nine Long-Chain Acyl-Coenzyme A Synthetase Genes That Participate in Fatty Acid and Glycerolipid Metabolism1
• Fatty Acid Elongation Is Independent of Acyl-Coenzyme A Synthetase Activities in Leek and Brassica napus1
• Identification of a Long-Chain Polyunsaturated Fatty Acid Acyl-Coenzyme A Synthetase from the Diatom Thalassiosira pseudonana1
• The multiple acyl-coenzyme A dehydrogenation disorders, glutaric aciduria type II and ethylmalonic-adipic aciduria. Mitochondrial fatty acid oxidation, acyl-coenzyme A dehydrogenase, and electron transfer flavoprotein activities in fibroblasts.
• Acyl-coenzyme A:cholesterol acyltransferases