REGULATION OF THIAMINE-DEPENDENT ENZYMES INVOLVED IN GLUCOSE

长期大量饮酒会导致营养不良， 伴随着体重和其他功能的损失。 这主要是由于 葡萄糖代谢异常，通常提供所需的能量， 维持正常的生理功能。据报道， 这些变化的主要候选人可能是由于缺乏 硫胺素，维生素B，是几种关键酶的辅助因子 在葡萄糖代谢中。 它们是丙酮酸脱氢酶，α- 酮戊二酸脱氢酶和转酮醇酶。 这些活动 酶在几种疾病状态下改变（减少）， 酗酒 尽管有许多关于生物化学的报道， 这些酶的性质、结构和分子调控具有 没有得到很好的调查。 由于这些酶在 能量代谢，这些调节的分子机制 酶进行了研究。 线粒体丙酮酸脱氢酶和α- 纯化酮戊二酸脱氢酶和胞质转酮醇酶， 在兔中产生同质性和特异性抗体。 这些 纯化的蛋白质进行N-末端和内部氨基酸 用于产生所需的寡脱氧核苷酸的测序分析 这些酶的cDNA克隆。 使用多克隆抗体和 寡脱氧核苷酸作为探针，这些酶的cDNA克隆， 识别和表征。 我们的研究结果表明， 硫胺素缺乏大鼠脑中免疫反应酶减少。 这些酶的减少机制正在研究中， 分子生物学方法。

Chronic heavy alcohol drinking leads to malnutrition often associated with losses of body weight and other functions. This is mainly due to aberrant metabolism of glucose which normally provides energy needed for maintaining normal physiological functions. It was reported that one of the leading candidates for these changes might be due to deficiency of thiamine, vitamin B, which is a cofactor for several key enzymes involved in glucose metabolism. These are pyruvate dehydrognease, alpha- ketoglutarate dehydrogenase, and transketolase. The activities of these enzymes were altered (reduced) in several disease states often associated with alcohol abuse. Despite numerous reports on the biochemical properties, the structures and molecular regulation of these enzymes have not been well investigated. Because of the importance of these enzymes in energy metabolism, the molecular mechanism of the regulation of these enzymes was studied. Mitochondrial pyruvate dehydrogenase and alpha- ketoglutarate dehydrogenase and cytosolic transketolase were purified to homogeneity and specific antibodies were generated in rabbits. These purified proteins were subjected to N-terminal and internal amino acid sequencing analyses for the generation of oligodeoxynucleotides needed for cDNA cloning for these enzymes. Using polyclonal antibodies and oligodeoxynucleotides as probes, cDNA clones for these enzymes were identified and characterized. Our results indicated that the amounts of immunoreactive enzymes are decreased in brain of thiamine deficient rats. The mechanism of the reduction in these enzymes is being studied by molecular biological approaches.