Pili mediated DNA exchange in the third domain of life

菌毛介导生命第三域的 DNA 交换

• 批准号: 209991535
• 负责人: Professorin Dr. Sonja Verena Albers
• 金额: --
• 依托单位: Forschungsschwerpunkt Mikrobiologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/209991535?language=en
• 关键词: Pili; mediated; DNA; exchange; third

Inter- and intra species transfer of DNA plays a vital role in processes like survival under stress conditions, acquiring new traits by horizontal gene transfer and pathogenesis. Different organisms have evolved a variety of mechanisms to transfer DNA to other cells or the environment or take up DNA. The thermoacidophilic archaeon Sulfolobus acidocaldarius possesses a unique pilus system that is induced by treatment with UV light and is subsequently involved in DNA exchange between aggregated Sulfolobus cells. This project will employ biochemical and genetic methods to elucidate the mechanism of pilus assembly, sensing of other Sulfolobus cells and initiation of auto-aggregation. Deletion mutant analysis will determine which proteins are important for pilus assembly and recognition of acceptor or donor cells. Once the receptor in the pilus is identified, the component(s) will be identified which triggers the signal for aggregation, surface attachment and initiation of DNA transfer. A set of genes downstream of the pili operon might be involved in homologous recombination of exchanged DNA into the Sulfolobus chromosome. Deletion mutant strains of these genes will be used in conjugation assays to show their involvement in UV light induced DNA repair. At the end of this project we aim to elucidate the mechanism how the UV induced pili are involved in cell aggregation, DNA exchange and DNA repair by homologous recombination.

DNA的种间和种内转移在逆境条件下的生存、通过水平基因转移获得新性状和致病等过程中起着至关重要的作用。不同的生物体已经进化出多种机制来将DNA转移到其他细胞或环境中或吸收DNA。嗜热嗜酸古菌酸热硫化叶菌具有独特的菌毛系统，该菌毛系统通过用UV光处理来诱导，并且随后参与聚集的硫化叶菌细胞之间的DNA交换。本计画将利用生物化学及遗传学的方法，来探讨菌毛的组装、感受其他硫化叶菌细胞及启动自聚集的机制。缺失突变体分析将确定哪些蛋白质对于菌毛组装和受体或供体细胞的识别是重要的。一旦菌毛中的受体被鉴定，将鉴定触发聚集、表面附着和DNA转移起始信号的组分。皮利操纵子下游的一组基因可能参与交换DNA到硫化叶菌染色体中的同源重组。这些基因的缺失突变株将用于接合测定，以显示它们参与UV光诱导的DNA修复。本课题的最后，我们希望阐明紫外线诱导的皮利参与细胞聚集、DNA交换和DNA同源重组修复的机制。