The in vivo coenzyme A intermediates involved in the metabolic pathway in which vitamin B,t serves as a coenzyme (conversion of methylmalonyl-CoA to succinyl-CoA) were measured in the livers of control and B12-deprived animals. Succinyl-CoA was assayed by the succinate thiokinase arsenolysis of succinyl-CoA coupled with 5’,5’-dithiobis(Znitrobenzoic acid) measurement of the liberated coenzyme A...

The enzyme 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) synthase catalyses the condensation of acetoacetyl-CoA and acetyl-CoA to form HMGCoA plus free CoA. The activity of HMG-CoA synthase is located in two different compartments: the cytosol and the mitochondria. The HMG-CoA produced by cytosolic HMG-CoA synthase is transformed into mevalonate by the action of HMG-CoA reductase, thus starting the ...

cu-Isopropylmalate synthase (EC 4.1.3.12) from Saccharomyces cerevisiae was purified to a purity of about 95%. The molecular weight of the enzyme is approximately 127,000, as determined by sedimentation equilibrium centrifugation and by intersubunit cross-linking. Under denaturing conditions, one major species (95%) with molecular weight of about 65,000 is obtained. The dimeric structure of the...

Bidirectional typing combines two modes of typing: type checking, which checks that a program satisfies known type, and synthesis, determines from the program. Using checking enables bidirectional to support features for inference is undecidable; using synthesis avoid large annotation burden explicitly typed languages. In addition, improves error locality. We highlight design principles underli...

Achieving minimum cost and time in reservoir drilling requires evaluating the effects of the drilling parameters on the penetration rate and constructing a drilling rate estimator model. Several drilling rate models have been presented using the drilling parameters. Among these, the Bourgoyne and Young (BY) model is widely utilized in order to estimate the penetration rate. This model relates s...

The X-ray crystallographic structure of medium-chain acyl-CoA dehydrogenase (MCAD)-octenoyl-CoA complex reveals that the 3'-phosphate group of CoA is confined to the exterior of the protein structure [approx. 15 A (1.5 nm) away from the enzyme active site], and is fully exposed to the outside solvent environment. To ascertain whether such a distal (3'-phosphate) fragment of CoA plays any signif...

Ignicoccus hospitalis is an anaerobic, autotrophic, hyperthermophilic Archaeum that serves as a host for the symbiotic/parasitic Archaeum Nanoarchaeum equitans. It uses a yet unsolved autotrophic CO(2) fixation pathway that starts from acetyl-CoA (CoA), which is reductively carboxylated to pyruvate. Pyruvate is converted to phosphoenol-pyruvate (PEP), from which glucogenesis as well as oxaloace...

The coenzyme A (CoA)-activated C5-dicarboxylic acids mesaconyl-CoA and beta-methylmalyl-CoA play roles in two as yet not completely resolved central carbon metabolic pathways in bacteria. First, these compounds are intermediates in the 3-hydroxypropionate cycle for autotrophic CO2 fixation in Chloroflexus aurantiacus, a phototrophic green nonsulfur bacterium. Second, mesaconyl-CoA and beta-meth...

The enzymes of fatty acid synthesis from liver and brain in normal and Blz-deprived rats were studied. Both total and specific activities of fatty acid synthetase and acetyl coenzyme A carboxylase were 2to 5-fold greater in Blz deprivation than in the normal state. The presence of excess activators in the BIp-deprived rat or an excess inhibitor in the normal rat was not found by serial admixtur...

Bacterial butyryl-CoA CoA-transferase activity plays a key role in butyrate formation in the human colon, but the enzyme and corresponding gene responsible for this activity have not previously been identified. A novel CoA-transferase gene is described from the colonic bacterium Roseburia sp. A2-183, with similarity to acetyl-CoA hydrolase as well as 4-hydroxybutyrate CoA-transferase sequences....