REGULATION OF SUGAR TRANSPORT AND METABOLISM IN LACTIC ACID AND ORAL BACTERIA

乳酸和口腔细菌中糖运输和代谢的调节

• 批准号: 3775658
• 负责人: J THOMPSON
• 金额: --
• 依托单位: NATIONAL INSTITUTE OF DENTAL & CRANIOFACIAL RESEARCH
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3775658
• 关键词: 6 phosphofructokinase; Fusobacterium; Streptococcus lactis; aminoacid metabolism; carbohydrate metabolism; carbohydrate transport; enzyme activity; gas chromatography mass spectrometry; genetic regulation; lactates; molecular cloning; nuclear magnetic resonance spectroscopy; nucleic acid sequence; oral bacteria; phosphoenolpyruvate; phosphotransferases; protein purification; protein sequence; site directed mutagenesis; triose phosphate isomerase

The primary goal(s) of this program are to understand the molecular basis, and the roles of microorganisms in the etiology and pathogenesis of oral diseases. The products of microbial metabolism, including organic acids and sulfur-containing compounds, are either causative or contributory agents to the development of dental caries, gingivitis and periodontitis. Consequently, our research efforts are concerned with the elucidation of the biochemical, enzymatic, and genetic factors, responsible for the fermentation of sugars and amino acids by oral microorganisms. Major accomplishments during the past year include: 1. The identification of a novel phosphoenolpyruvate-dependent maltose:phosphotransferase system in Fusobacterium mortiferum. 2. The purification to homogeneity of two enzymes required for the metabolism of sugars by lactic acid bacteria. Fructokinase II catalyzes the ATP-dependent phosphorylation of fructose, whereas triosephosphate isomerase is a key enzyme for the fermentation of sugars via the Embden-Meyerhof-Parnas (glycolytic) pathway. 3. Site-directed mutagenesis has facilitated identification of substrate binding and catalytically functional residues in N5- (carboxyethyl)ornithine synthase. 4. Beta-Cystathionase has been purified, cloned and sequenced from Bordetella avium. The biochemical basis for the toxicity of this (pyridoxal-phosphate containing) protein toward osteogenic cells has been established. Site-directed mutagenesis experiments have provided evidence for participation of the lysyl residue K214 in co-factor binding, and for the role(s) of cysteine residues in the catalytic process. 5. Antibodies prepared against Beta-cystathionase from B. avium have been used to screen for the same (or, related) enzyme(s) in extracts of oral pathogens including Fusobacteria and Bacteroides species. Results from this research program have been published in peer- reviewed Journals, and have also been discussed in a textbook chapter dealing with the regulation of sugar transport and metabolism by lactic acid bacteria.

该计划的主要目标是了解分子 基础以及微生物在病原学和病原学中的作用 口腔疾病的发病机制。 微生物产物 新陈代谢，包括有机酸和含硫物质 化合物，要么是致病因素，要么是促成因素 龋齿、牙龈炎和牙周炎的发展。 因此，我们的研究工作涉及 阐明生化、酶促和遗传因素， 负责通过口腔发酵糖和氨基酸 微生物。 过去一年主要业绩 包括： 1. 新型磷酸烯醇丙酮酸依赖性蛋白的鉴定 麦芽糖：腐烂梭杆菌中的磷酸转移酶系统。 2. 纯化所需的两种酶均质 乳酸菌对糖的代谢。 果糖激酶II 催化果糖的 ATP 依赖性磷酸化，而 磷酸丙糖异构酶是发酵的关键酶 通过 Embden-Meyerhof-Parnas（糖酵解）途径分解糖。 3. 定点诱变有利于鉴定 N5- 中的底物结合和催化功能残基 (羧乙基)鸟氨酸合酶。 4. β-胱硫醚酶已从以下来源纯化、克隆和测序 鸟博德特氏菌。 该物质毒性的生化基础 （含磷酸吡哆醛）蛋白对成骨细胞 已成立。 定点诱变实验 提供了赖氨酰残基 K214 参与的证据 辅因子结合，以及半胱氨酸残基在 催化过程。 5. 针对来自鸟博德氏菌的β-胱硫醚酶制备的抗体 已用于筛选相同（或相关）的酶 口腔病原体提取物，包括梭杆菌和拟杆菌 物种。 该研究计划的结果已发表在同行杂志上 审阅了期刊，并且也在教科书中进行了讨论 涉及糖运输监管的章节和 乳酸菌的代谢。