DEWAN [1938] and Adler et al. [1939] reported that certain enzyme preparations obtained from heart muscle bring about a reductive amination of ac-ketoglutaric acid. The hydrogen required in this reaction may be provided from other dehydrogenase systems via coenzyme I or II, especially from the ,-hydroxybutyric and i8ocitric dehydrogenases, according to the schemes: (1) ac-ketoglutaric acid+NH3+...

Herein we report a study combining metabolomics and mass isotopomer analysis used for investigation of the biochemical fate of γ-hydroxybutyric acid (GHB). Using various (13)C incorporation labeling patterns into GHB, we have discovered that GHB is catabolized by previously unknown processes that include (i) direct β-oxidation to acetyl-CoA and glycolate, (ii) α-oxidation to 3-hydroxypropionyl-...

Previously our laboratory demonstrated that voluntary muscle fiber groups and diaphragms from depanereatized and alloxan-diabetic rats take up leas acetoacetic acid than fiber groups and diaphragms from control animals (1, 2). The addition of glucose and insulin causes an increase in acetoacetic acid uptake by muscle fiber groups from both control and depancreatized rats. These experiments were...

In humans, deficiencies in coenzyme B12-dependent methylmalonyl-CoA mutase (MCM) lead to methylmalonyl aciduria, a rare disease that is often fatal in newborns. Such deficiencies can result from inborn errors in the MCM structural gene or from mutations that impair the assimilation of dietary cobalamins into coenzyme B12 (Ado-B12), the required cofactor for MCM. ATP:cob(I)alamin adenosyltransfe...

A capillary zone electrophoresis method was optimised to analyse low-molecular-mass organic acids for the purpose of monitoring diabetes in rat plasma. The method included acetoacetic, 2-hydroxybutyric, lactic and uric acids. A variation in the background electrolyte allowed us to measure pyruvic acid in the same sample. Conditions have been optimised for measuring a large number of plasma samp...

An enzymatic-HPLC method to analyze the serum concentration of D-3-hydroxybutyric acid was developed. A deproteinized sample of rat serum was treated with 3-hydroxybutyrate dehydrogenase in the presence of NAD, and was analyzed by reversed-phase HPLC to separate and quantify NADH formed by the enzyme reaction, monitoring OD at 340 nm. Standard samples containing varying amounts of D-3-hydroxybu...