GROWTH AND METABOLISM OF ORAL MICROORGANISMS

口腔微生物的生长和代谢

• 批准号: 2572321
• 负责人: S A ROBRISH
• 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/2572321
• 关键词: Fusobacterium nucleatum; Klebsiella pneumoniae; adenylate kinase; aminoacid metabolism; carbohydrate metabolism; fermentation; glucose transport; microorganism culture; microorganism growth; microorganism metabolism; oral bacteria; phosphoenolpyruvate; phosphotransferases

Organisms of the genus Fusobacterium are important human and animal pathogens which are isolated frequently from liver and brain abscesses. F. nucleatum is isolated from normal subgingival dental plaque but its numbers increase dramatically in cases of gingivitis and periodontitis suggesting pathogenic potential. Little is known about the physiology of the fusobacteria and most published reports refer to these organisms as asaccharolytic although sugar use is easily demonstrated. Previous work in this laboratory has shown that glucose transport by F. nucleatum is dependent on energy provided by the fermentation of amino acids. In addition, we have shown extensive sugar use by F. mortiferum strongly suggesting that this organism can be used successfully as a model for genetic studies which are lacking in the fusobacteria. In the past year we have concentrated on the proof of the cellobiose phosphoenolpyruvate phosphotransferase (PTS) use in F. mortiferum. A cellobiose PTS assumes the intermediate formation of cellobiose-6-P and its subsequent hydrolysis by a specific hydrolase. Cellobiose-6-P and a variety of other beta disaccharide phosphates were made using an ATP kinase purified from Klebsiella pnemoniae. The beta glucoside phosphates had the predicted molecular weight when analyzed by mass spectrometry and were all hydrolyzed by the 54 KD protein from cellobiose grown F. mortiferum which we suggested as the cellobiose- 6-P hydrolase. In addition, an artificial beta glucoside phosphate was made from p nitrophenyl beta D glucoside [PNP beta GP]. The hydrolysis of PNP beta GP gave a yellow color which could be used to quantitate the hydrolase activity or be used qualitatively to follow the purification of the enzyme. The cellobiose phosphate hydrolase retained activity in air in contrast to the maltose-6-P hydrolase. Washed, cellobiose grown cells of F. mortiferum used limited amounts of cellobiose from a buffered suspension when incubated aerobically. The aerobic inhibition of cellobiose use was gradual, rather than abrupt, as in the maltose system of the same organism.

梭杆菌属的生物体是重要的人类和动物 常见的病原体是从肝脏和大脑中分离出来的 公主。 F.从正常龈下牙齿中分离出核仁 但在牙龈炎的情况下， 和牙周炎提示致病潜力。 知之甚少 关于梭菌的生理学和大多数已发表的报告 我把这些微生物称为溶糖菌，尽管糖的使用是 很容易证明。 该实验室以前的工作表明， 葡萄糖的转运。有核物质依赖于 氨基酸的发酵。 此外，我们还表明， 广泛的糖使用F. Mortiferum强烈表明， 一个有机体可以成功地用作遗传学研究的模型 这是梭菌所缺乏的。 在过去的一年里， 专注于证明纤维二糖磷酸烯醇丙酮酸 磷酸转移酶（PTS）在F.死亡 A纤维二糖PTS 假设纤维二糖-6-P的中间体形成及其 随后被特定水解酶水解。 纤维二糖-6-P和a 各种其他β-二糖磷酸盐是使用ATP 从肺炎克雷伯氏菌纯化的激酶。 β-葡萄糖苷 当通过质量分析时，磷酸盐具有预测的分子量 的54 KD蛋白质水解， 纤维二糖生长的F.我们认为是纤维二糖 6-P水解酶。 此外，人工β-葡糖苷磷酸盐 由对硝基苯基β D葡萄糖苷[PNP β GP]制成。 的 PNP β GP水解得到黄色，其可用于 定量水解酶活性或定性用于跟踪 酶的纯化。 纤维二糖磷酸水解酶 与麦芽糖-6-P水解酶相反，在空气中保留活性。 洗涤的纤维二糖生长的F. Mortiferum使用限量 当有氧培养时，从缓冲悬浮液中提取纤维二糖。 有氧抑制纤维二糖的使用是渐进的，而不是 突然的，如在同一有机体的麦芽糖系统中。