6-Methylsalicylic acid synthase has been isolated in homogeneous form from Penicillium patulum grown in liquid culture from a spore inoculum. The enzyme is highly susceptible to proteolytic degradation in vivo and in vitro, but may be stabilized during purification by incorporating proteinase inhibitors in the buffers. The enzyme exists as a homotetramer of M(r) 750,000, with a subunit M(r) of ...

Our model of the native fatty acid synthase (FAS) depicts it as a dimer of two identical multifunctional proteins (Mr approximately 272,000) arranged in an antiparallel configuration so that the active Cys-SH of the beta-ketoacyl synthase of one subunit (where the acyl group is attached) is juxtaposed within 2 A of the pantetheinyl-SH of the second subunit (where the malonyl group is bound). Th...

Fatty acids are synthesized de novo from acetyl-CoA and malonyl-CoA through a series of reactions mediated by acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS). In rodents, the principal fatty acid produced by FAS is palmitic acid (16:0). Sterol regulatory element-binding proteins (SREBPs) enhance the transcription of many genes responsible for fatty acid synthesis. In transgenic mice ...

constantpolyunsaturated/monounsaturated/saturatedfatty acids snd p-6!n-3 ratios ef dietary fats in rats. Dietary fat centaining linoleic a id as the sole polyunsaturated fatty acid (PUFA) vvas alse given as a contrel. The cencentration of serum triglyceride and phosphelipid in the three n-3 PUFA groups was lower than in the linoleic acid groilp. The hepatic higlyceride concentration was lower a...

The biosynthetic pathway of medium-chain-length (MCL) polyhydroxyalkanoates (PHAs) from fatty acids has been established in fadB mutant Escherichia coli strain by expressing the MCL-PHA synthase gene. However, the enzymes that are responsible for the generation of (R)-3-hydroxyacyl coenzyme A (R3HA-CoAs), the substrates for PHA synthase, have not been thoroughly elucidated. Escherichia coli Mao...

A double-tagging, dual affinity chromatographic procedure, which permits isolation of dimers independently mutated in each subunit, has been exploited to probe the functional topology of the animal fatty acid synthase. Dimers were engineered in which the chainterminating thioesterase reaction was compromised by mutation of the (active-site) serine residue in both subunits; these dimers assemble...

The abbreviations used are: PPAR, peroxisome proliferator-activated receptor; PPRE, peroxisome proliferator response element(s); AOX, straight chain fatty acyl-CoA oxidase; L-PBE, peroxisomal enoylCoA hydratase/3-hydroxyacyl-CoA dehydrogenase bifunctional protein; PTL, peroxisomal 3-ketoacylCoA thiolase; G-6-P, glucose-6-phosphatase; C/EBPα, CCAAT enhancer-binding protein α; SREBP1, sterol regu...