SEX PHEROMONES AND CONJUGATION IN STREPTOCOCCI

链球菌中的性信息素和结合

• 批准号: 3284185
• 负责人: DON B CLEWELL
• 金额: $ 19.55万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-03-01 至 1990-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3284185
• 关键词: Enterococcus; Escherichia coli; bacterial DNA; bacterial genetics; density gradient ultracentrifugation; gel electrophoresis; gene expression; genetic manipulation; genetic mapping; genetic recombination; immunochemistry; mass spectrometry; microorganism conjugation; microorganism culture; molecular cloning; mutant; nuclear magnetic resonance spectroscopy; nucleic acid sequence; pheromone; plasmids; structural genes; transposon /insertion element

The primary objective of the proposed work is to characterize key molecular aspects of sex pheromone-related mating systems in Streptococcus faecalis. Attention will be focussed on both the production of sex pheromones by recipients and the response to such pheromones by certain plasmid-containing donors. Parts of the study will make use of the recently characterized transposons Tn916 and Tn917. More specifically we will: 1) Genetically analyze the pAD1 pheromone response, making use of Tn917 as an insertional mutagen and an E. coli-streptococcus "shuttle vector" to clone and genetically analyze selected segments of the plasmid; 2) Identify plasmid-encoded (controlled) protein and RNA species that are induced during the cAD1 pheromone response and attempt to relate the proteins to pAD1 determinants revealed from genetic studies; 3) Generate mutants of Streptococcus faecalis that fail to excrete cPD1, examine their ability to excrete other pheromones and to behave as a recipient, and use them to explore the possible existence of pheromone precursor peptides; 4) Clone and sequence segments of DNA believed to contain the structural gene for sex pheromone; 5) Purify and characterize cAD1 and cPD1 and attempt to relate their amino acid sequences to cloned genomic DNA base sequences; 6) Determine the nature by which sex pheromone production is shut off after plasmid acquisition, by analyzing newly discovered plasmid encoded modified forms of cAD1 and cPD1; and 7) Using a panel of S. faecalis "responder" strains, screen culture filtrates of other bacterial species for pheromone activity.

拟议工作的主要目标是表征关键分子 粪链球菌中性信息素相关交配系统的各个方面。 注意力将集中在性信息素的产生上 接受者和某些人对此类信息素的反应 含有质粒的供体。 该研究的部分内容将利用 最近鉴定了转座子 Tn916 和 Tn917。 更具体地说，我们 将： 1) 利用基因分析 pAD1 信息素反应 Tn917 作为插入诱变剂和大肠杆菌-链球菌“穿梭机” 载体”来克隆和遗传分析质粒的选定片段； 2) 鉴定质粒编码（受控）的蛋白质和 RNA 种类 在 CAD1 信息素反应期间诱导并尝试将 遗传研究揭示了 pAD1 决定簇的蛋白质； 3）生成 无法分泌 cPD1 的粪链球菌突变体，检查其 排泄其他信息素并充当接收者的能力，并使用 他们探索信息素前体肽的可能存在； 4） 据信含有结构基因的 DNA 克隆和序列片段 用于性信息素； 5) 纯化并表征 cAD1 和 cPD1，并尝试 将它们的氨基酸序列与克隆的基因组DNA碱基序列联系起来； 6） 确定性信息素产生在之后被关闭的性质 质粒获取，通过分析新发现的质粒编码修饰 cAD1 和 cPD1 的形式； 7) 使用一组粪链球菌“响应者” 菌株、其他细菌种类的培养滤液的信息素筛选 活动。