Characterization of a Fatty Acid Synthetase from \u3ci\u3eCorynebacterium diphtheriae\u3c/i\u3e

A fatty acid synthetase from Corynebacterium diphtheriae has been purified to a specific activity of 450 nmoles of malonyl coenzyme A incorporated per min per mg. The enzyme is optimally active in 0.5 M phosphate buffer. C. diphtheriae appears to be the most primitive organism having a multienzyme complex for fatty acid synthesis

Palmityl Coenzyme A Inhibition of Fatty Acid Synthesis

The effects of acyl-CoA derivatives (C8 to C20) on the activity of the fatty acid synthetases from yeast and Corynebacterium diphtheriae have been examined. Both enzyme systems are inhibited by the longer chain acyl thioesters (C16 to C20) and protected against this inhibition by bovine serum albumin (BSA). Identical relief from acyl-CoA inhibition is provided by the 6-0-methylglucose-containing lipopolysaccharide (MGLP), from Mycobacterium phlei. It is shown that MGLP forms a stable complex with palmitylCoA. This interaction accounts for the BSA-like effects of the polysaccharide. BSA and MGLP have two further effects on the fatty acid synthetases under study, also attributable to complex formation with palmityl-CoA. They stimulate the rate of over-all synthesis from acetyl-CoA and malonyl-CoAt and they cause a shift of the fatty acid pattern towards products of shorter chain length. The observed effects are discussed in terms of the regulation of fatty acid synthesis both with respect to rate and product composition. It is concluded that in the two microbial enzyme systems negative feedback inhibition and its relief are important control mechanisms

Characterization of a Fatty Acid Synthetase from \u3ci\u3eCorynebacterium diphtheriae\u3c/i\u3e

A fatty acid synthetase from Corynebacterium diphtheriae has been purified to a specific activity of 450 nmoles of malonyl coenzyme A incorporated per min per mg. The enzyme is optimally active in 0.5 M phosphate buffer. C. diphtheriae appears to be the most primitive organism having a multienzyme complex for fatty acid synthesis

Palmityl Coenzyme A Inhibition of Fatty Acid Synthesis

The effects of acyl-CoA derivatives (C8 to C20) on the activity of the fatty acid synthetases from yeast and Corynebacterium diphtheriae have been examined. Both enzyme systems are inhibited by the longer chain acyl thioesters (C16 to C20) and protected against this inhibition by bovine serum albumin (BSA). Identical relief from acyl-CoA inhibition is provided by the 6-0-methylglucose-containing lipopolysaccharide (MGLP), from Mycobacterium phlei. It is shown that MGLP forms a stable complex with palmitylCoA. This interaction accounts for the BSA-like effects of the polysaccharide. BSA and MGLP have two further effects on the fatty acid synthetases under study, also attributable to complex formation with palmityl-CoA. They stimulate the rate of over-all synthesis from acetyl-CoA and malonyl-CoAt and they cause a shift of the fatty acid pattern towards products of shorter chain length. The observed effects are discussed in terms of the regulation of fatty acid synthesis both with respect to rate and product composition. It is concluded that in the two microbial enzyme systems negative feedback inhibition and its relief are important control mechanisms