Ilyobacter delafieldii produced an extracellular poly-[3-hydroxybutyrate (PHB) depolymerase when grown on PHB; activity was not detected in cultures grown on 3-hydroxybutyrate, crotonate, pyruvate or lactate. PHB depolymerase activity was largely associated with the PHB granules (supplied as growth substrate), and only 16 % was detected free in the culture supernatant. Monomeric 3-hydroxybutyra...

Freshly isolated Morris Hepatoma 7777 cells were prepared for a study of the utilization of palmitate and beta-hydroxybutyrate as metabolic fuels compared to other major energy substrates (glucose and glutamine). These cells were capable of oxidizing both [U-14C]palmitate and beta-[3-14C]hydroxybutyrate although the rates accounted for only 10 +/- 3 (SD) and 9 +/- 4% of total oxygen consumed, r...

The metabolism of acetoacetate via a proposed cytosolic pathway in brain of 1-week-old rats was investigated. (-)-Hydroxycitrate, an inhibitor of ATP citrate lyase, markedly inhibited the incorporation of carbon from labelled glucose and 3-hydroxybutyrate into cerebral lipids, but had no effect on the incorporation of labelled acetate and acetoacetate into brain lipids. Similarly, n-butylmalona...

A⁻β⁺ ketosis-prone diabetes (KPD) is an emerging syndrome of obesity, unprovoked ketoacidosis, reversible β-cell dysfunction, and near-normoglycemic remission. We combined metabolomics with targeted kinetic measurements to investigate its pathophysiology. Fasting plasma fatty acids, acylcarnitines, and amino acids were quantified in 20 KPD patients compared with 19 nondiabetic control subjects....

A 3-hydroxypropionate/4-hydroxybutyrate cycle operates during autotrophic CO(2) fixation in various members of the Crenarchaea. In this cycle, as determined using Metallosphaera sedula, malonyl-coenzyme A (malonyl-CoA) and succinyl-CoA are reductively converted via their semialdehydes to the corresponding alcohols 3-hydroxypropionate and 4-hydroxybutyrate. Here three missing oxidoreductases of ...

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....

Rat liver mitochondria isolated in 0.25 M sucrose were osmotically lysed with distilled water. The effect of osmotic lysis on mitochondrial compartmentation was monitored by following the changes in the specific Mg(++)-ATPase and the stimulation of this activity by DNP. Each resuspension in distilled water caused a progressive increase in the specific Mg(++)-ATPase and a decrease in DNP-stimula...

Poly(lactate-co-glycolate), PLGA, is a representative synthetic biopolymer widely used in medical applications. Recently, we reported one-step direct fermentative production of PLGA and its copolymers by metabolically engineered Escherichia coli from xylose and glucose. In this study, we report development of metabolically engineered E. coli strains for the production of PLGA and poly(d-lactate...

Kabuki syndrome is a Mendelian intellectual disability syndrome caused by mutations in either of two genes (KMT2D and KDM6A) involved in chromatin accessibility. We previously showed that an agent that promotes chromatin opening, the histone deacetylase inhibitor (HDACi) AR-42, ameliorates the deficiency of adult neurogenesis in the granule cell layer of the dentate gyrus and rescues hippocampa...