Thiamine deficiency (TD) is accepted as the cause of beriberi because of its action in the metabolism of simple carbohydrates, mainly as the rate limiting cofactor for the dehydrogenases of pyruvate and alpha-ketoglutarate, both being critical to the action of the citric acid cycle. Transketolase, dependent on thiamine and magnesium, occurs twice in the oxidative pentose pathway, important in p...

TK (transketolase) undergoes inactivation during biocatalytic processes due to oxidation, substrate and product inhibition, reactivity of aldehyde substrates, irreversible inactivation at low pH, and dissociation of cofactors. However, the contribution of protein denaturation to each of these mechanisms is not fully understood. The urea-induced reversible denaturations of the apo- and holo-enzy...

Rapid biocatalytic process development and intensification continues to be challenging with currently available methods. Chiral amino-alcohols are of particular interest as they represent key industrial synthons for the production of complex molecules and optically pure pharmaceuticals. (2S,3R)-2-amino-1,3,4-butanetriol (ABT), a building block for the synthesis of protease inhibitors and detoxi...

Genetic and biochemical evidence that sedoheptulose-7-phosphate is an obligatory precursor of the L-glycero-D-mannoheptose residues of the lipopolysaccharide of Salmonella was obtained by isolation and characterization of transketolase-negative mutants of Salmonella typhimurium. These mutants, which are defective in synthesis of sedoheptulose-7-phosphate, were found to produce an incomplete hep...

Both endogenous and exogenous sex steriods may induce changes in plasma vitamin levels by altering availability, transport, binding, or use of vitamins. This study investigated some of those mechanisms by observing in a primate model (baboon), the blood levels of carotene, folate, vitamins A, B12, and C, and the status of vitamin B6, riboflavin, and thiamin. The latter three vitamins were studi...

BACKGROUND Canine mammary tumors represent the most common neoplasm in female dogs, and the discovery of cancer biomarkers and their translation to clinical relevant assays is a key requirement in the war on cancer. Since the description of the 'Warburg effect', the reprogramming of metabolic pathways is considered a hallmark of pathological changes in cancer cells. In this study, we investigat...

In vivo corneal light scattering measurements using a novel confocal microscope demonstrated greatly increased backscatter from corneal stromal fibrocytes (keratocytes) in opaque compared to transparent corneal tissue in both humans and rabbits. Additionally, two water-soluble proteins, transketolase (TKT) and aldehyde dehydrogenase class 1 (ALDH1), isolated from rabbit keratocytes showed unexp...

Thiamine, known as vitamin B(1), plays an essential role in energy metabolism. Benfotiamine (S-benzoylthiamine O-monophoshate) is a synthetic S-acyl derivative of thiamine. Once absorbed, benfotiamine is dephosphorylated by ecto-alkaline phosphatase to lipid-soluble S-benzoylthiamine. Transketolase is an enzyme that directs the precursors of advanced glycation end products (AGEs) to pentose pho...

Eosinophilic esophagitis is an inflammatory condition, causing dysphagia, food impaction and chest pain. A minimum of 15 eosinophils per high power field by esophageal biopsy is necessary for diagnosis. It has become an increasingly important cause of gastrointestinal morbidity in the past two decades. A 14 year old boy had received a diagnosis of eosinophilic esophagitis elsewhere at the age o...