Structural Studies of Bacterial Competence Proteins

细菌活性蛋白的结构研究

• 批准号: 6848624
• 负责人: John Cavanagh
• 金额: $ 13.67万
• 依托单位: NORTH CAROLINA STATE UNIVERSITY RALEIGH
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-02-01 至 2007-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6848624
• 关键词: Bacillus subtilis; bacterial genetics; bacterial proteins; cell transformation; electrospray ionization mass spectrometry; genetic recombination; nuclear magnetic resonance spectroscopy; protein protein interaction; protein sequence; protein structure function; surface plasmon resonance

DESCRIPTION (provided by applicant): Bacteria have obtained a significant portion of their genetic diversity, metabolic fitness and lethality through the acquisition of nucleotide sequences from both closely and distantly related organisms. Horizontal gene transfer produces extremely dynamic genomes, in which substantial amounts of DNA are transferred between the chromosomes of different bacterial strains. Without question, such transfers have changed the ecological and pathogenic character of bacterial species. Transformation represents one of the main mechanisms by which DNA is incorporated into the recipients genome. It involves the uptake of naked DNA from the environment and has the potential to transmit DNA between distantly related organisms. For bacteria to be transformable, they must develop the physiological state referred to as competence. Genetic competence is defined as the ability of a cell to take up free DNA from the surrounding medium. If the cell is not competent, it cannot be transformed and its growth, survival and evolution are compromised. Research into the very nature of competence addresses both very fundamental and very practical questions and concerns. What mechanisms allow bacteria to incorporate new genes to develop novel, more sophisticated mechanisms for survival? By what means is genetic diversity provided, such that a microorganism can enlarge its own genomic complement? From a health related perspective, genetic transfer via competence is becoming more implicated in the development of the pathogenic character of bacteria. There is mounting evidence that virulent attributes and antibiotic resistance can be introduced and/or enhanced in this manner. The studies proposed here will focus on mechanistic characteristics of a set of interacting proteins that form the critical regulatory network initiating competence development in Bacillus subtilis. The goals of the research are to provide structural, dynamic and interaction information, in order to understand the regulatory effects of the proteins MecA, ComS, ClpP/C and ComK (and their complexes). This will be achieved by a combination of high-resolution NMR spectroscopy, electrospray mass spectrometry, surface plasmon resonance and other bioanalytical techniques, along with mutagenesis and protease foot-printing investigations. The results from these studies will provide a basis for the development of models to describe the mechanism of activation of competence, not only in B. subtilis, but also in other important gram-positive (e.g. Streptococcus pneumoniae) and gram-negative (e.g. Neisseria gonorrhoeae and Haemophihts influenza) bacteria.

描述（由申请人提供）：细菌通过从密切和遥远相关的生物体中获取核苷酸序列，获得了其遗传多样性，代谢适应性和致死性的很大一部分。水平基因转移会产生极其动态的基因组，其中大量的DNA在不同细菌菌株的染色体之间转移。毫无疑问，这种转移改变了细菌物种的生态和致病性。转化是将DNA纳入受体基因组的主要机制之一。它涉及从环境中吸收裸露的DNA，并且有可能在远距离相关的生物之间传输DNA。为了使细菌转变，它们必须发展为称为能力的生理状态。遗传能力被定义为细胞从周围培养基中占据游离DNA的能力。如果细胞不胜任，它将无法转化，并且其生长，生存和进化将受到损害。对能力的本质的研究既解决非常基本的问题和非常实用的问题和关注点。哪些机制使细菌能够结合新基因来开发新颖，更复杂的生存机制？ 提供遗传多样性的方式，使微生物可以扩大其自身的基因组补体？ 从与健康相关的角度来看，通过能力的遗传转移越来越涉及细菌的致病性发展。有越来越多的证据表明，可以以这种方式引入和/或增强有毒属性和抗生素耐药性。此处提出的研究将重点关注一组相互作用蛋白的机械特征，这些蛋白质构成了枯草芽孢杆菌启动能力发展的关键调节网络。研究的目标是提供结构，动态和交互信息，以了解蛋白质MECA，COM，COMS，CLPP/C和COMK（及其复合物）的调节作用。这将通过高分辨率NMR光谱，电喷雾质谱法，表面等离子体共振和其他生物分析技术以及诱变和蛋白酶脚印研究的结合来实现。这些研究的结果将为开发模型的开发提供基础，以描述枯草芽孢杆菌的激活机理，而且还在其他重要的革兰氏阳性（例如肺炎链球菌）和革兰氏阴性菌（例如，Gonorrhoeae neisseria gonorrhoeae和Haemophihts fallenza）中。