Regulation of Sugar Transport and Metabolism in Lactic Acid and Oral Bacteria

口腔中的牙菌斑和其他生物膜 在龋齿、牙周炎和牙周炎的病因学方面发挥重要作用 牙周炎。生物体的致病潜能，包括 多物种生态系统是多方面的。然而，很明显， 通过口服的氨基和糖发酵的最终产物 微生物，是发展中的贡献因素 这些疾病和其他疾病。所形成的代谢产物 革兰氏阳性链球菌(例如变形链球菌)和 革兰氏阴性厌氧菌(例如核梭杆菌) 包括短链羧酸和含硫 衍生品。有机酸对土壤的脱矿作用 牙齿表面早已被认识到，其强大的细胞毒性 硫化物和硫醇对上皮细胞的影响也 有记录在案。令人惊讶的是，人们对这一规定知之甚少 构成这些不同的基因和酶 口腔细菌的发酵途径。此外，尽管 梭杆菌--包括核梭杆菌--含有多种 硫氢酶和脱硫酶，这些酶还没有被 在遗传、结构和催化水平上具有特征。这个 这个项目的目标是双重的。第一，提纯和表征 构成口腔能量产生途径的酶 细菌。第二，阐明遗传和生化 负责调控表达和表达的机制 这些蛋白质的催化活性。

Dental plaque and other biofilms in the oral cavity play an important role in the etiology of dental caries, gingivitis and periodontitis. The pathogenic potential of the organisms comprising the multi-species ecosytems is multi-faceted. However, it is clear that the end products of amino and sugar fermentations by oral microorganisms, are contributing factors in the development of these and other diseases. The metabolic products formed by Gram-positive streptococci (eg. Streptococcus mutans) and Gram-negative anaerobic species (eg. Fusobacterium nucleatum ) include short-chain carboxylic acids and sulfur-containing derivatives. The demineralizing action of organic acids upon the tooth surface has long been recognized, and the potent cytotoxicity of sulfides and mercaptans toward epithelial cells has also been documented. Surprisingly, little is known concerning the regulation of the genes and enzymes that constitute these different fermentation pathways in oral bacteria. Furthermore, although Fusobacteria- including F. nucleatum - contain a variety of sulfhydrase and desulfhydrases, these enzymes have yet to be characterized at the genetic, structural and catalytic levels. The goals of this program are two-fold. First, to purify and characterize the enzymes that constitute the energy-yielding pathways of oral bacteria. Second, to elucidate the genetic and biochemical mechanisms responsible for the regulation of expression and catalytic activity of these proteins.