S MUTANS CARIOGENICITY--ENVIRONMENTAL RESPONSES

变异链球菌致龋性--环境响应

• 批准号: 2131607
• 负责人: HOWARD K KURAMITSU
• 金额: $ 15.12万
• 依托单位: STATE UNIVERSITY OF NEW YORK AT BUFFALO
• 依托单位国家: 美国
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-09-30 至 1999-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2131607
• 关键词: Escherichia coli; Streptococcus mutans; acidity /alkalinity; bacterial genetics; biological signal transduction; cell growth regulation; dental caries; diacylglycerols; environmental stressor; enzyme activity; gene expression; genetic regulation; glycerol kinase; glycoproteins; guanine nucleotide binding protein; lipid metabolism; membrane proteins; membrane structure; oral bacteria; tissue /cell culture; virulence

The molecular basis for the aciduric properties of Streptococcus mutans will be investigated in this proposal. Utilizing both biochemical and molecular genetic approaches, several of the genes which have been implicated in this environmental response will be investigated. One of these genes recently isolated in this laboratory, dgk coding for diacylglycerol kinase, will be further characterized following purification of its gene product. In addition, since the accumulation of diacylglycerol may mediate external environmental responses in these organisms as has been demonstrated for eucaryotic cells, potential target sites for this cell regulator will be evaluated. Likewise the molecular basis for external acid regulation of diacylglycerol levels will be investigated. Another gene which may play a role in environmental regulation of S. mutans growth, sgp coding for a GTP-binding protein, has been identified immediately downstream from dgk gene within the same operon. Therefore, the role of this gene in environmental stress responses will also be evaluated in this proposal. Furthermore, target sites for the SGP protein will be determined as well as the mechanisms operating to regulate the expression of DGK and SGP. This information will be utilized to evaluate a signal transduction model for the involvement of diacylglycerol and the S. mutans G-protein in aciduricity. Since aciduricity appears to be a key cariogenic property of the mutans streptococci, the information derived from this proposal could be useful in developing novel strategies for neutralizing the cariogenic potential of these organisms.

变形链球菌耐酸特性的分子基础 将在本提案中进行调查。同时利用生化和 分子遗传学方法，其中一些基因已被 与此环境响应有关的人员将受到调查。之一 这些基因最近在本实验室分离出来，dgk 编码为 二酰甘油激酶，将进一步表征如下 其基因产物的纯化。另外，由于积累 二酰甘油可能介导这些中的外部环境反应 已证明真核细胞的生物体是潜在的靶标 将评估该细胞调节剂的位点。同样，分子 二酰甘油水平的外部酸调节的基础是 调查了。 另一个可能在 S. 的环境调节中发挥作用的基因。 突变体生长，编码 GTP 结合蛋白的 sgp，已被鉴定 紧邻同一操纵子内 dgk 基因的下游。所以， 该基因在环境应激反应中的作用也将是 在此提案中进行了评估。此外，SGP 蛋白的靶位点 将确定以及监管的运作机制 DGK 和 SGP 的表达。 该信息将用于评估 二酰甘油参与的信号转导模型 变形链球菌 G 蛋白的酸尿度。 由于酸尿性似乎是变形链球菌的一个关键致龋特性 链球菌，从该提案中获得的信息可能有用 开发中和潜在致龋性的新策略 这些生物体。