Principles of Protein Mimicry of DNA

DNA 蛋白质模拟原理

• 批准号: 8019526
• 负责人: Michael D. Brenowitz
• 金额: $ 33.35万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-02-20 至 2013-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8019526
• 关键词: Antibiotic Resistance; Antibiotics; Binding; Binding Proteins; Biochemical; Biological; Biological Models; Biological Process; Characteristics; Charge; Clinical; Complex; DNA; DNA Gyrase; DNA Mimicry; DNA analysis; Development; Drug resistance; Electrostatics; Enzymes; Family; Fluoroquinolones; Foundations; Genus Mycobacterium; Goals; Hand; Heart; Human; Investigation; Ions; Laboratories; Mediating; Metabolic Pathway; Modeling; Molecular; Mutagenesis; Mycobacterium tuberculosis; Nucleic Acids; Peptides; Physical condensation; Plasmids; Play; Process; Property; Protein Family; Protein Footprinting; Proteins; Quinolones; Regulation; Resistance; Resolution; Role; Scaffolding Protein; Shapes; Solutions; Specificity; Structure; Surface; Testing; Therapeutic; Therapeutic Index; Thermodynamics; Toxic effect; Tuberculosis; Vision; Xanthomonas albilineans; base; driving force; fluoroquinolone resistance; member; mimicry; new therapeutic target; novel; pathogen; physical property; planetary Atmosphere; protein folding; protein function; therapeutic protein

DESCRIPTION (provided by applicant): This revised application of a new proposal describes a comprehensive biochemical and biophysical investigation into the `DNA mimicry' of a recently discovered member of the Pentapeptide Repeat Protein (PRP) family of proteins. The atomic resolution structure of the MfpA PRP from Mycobacterium tuberculosis revealed a new protein fold; MfpA's right-handed 2-helical coils yield an elongated structure that is a remarkable mimic of the size, shape and electrostatic surface of DNA. That DNA mimicry is important to the biological role of MfpA is suggested by its ability to confer resistance to fluoro- quinolones by binding DNA gyrase thereby inhibiting its function. We will test the hypothesis that mimicry of the physical properties DNA by MfpA is the heart of its ability to confer drug resistance. Our long term goal is to understand the molecular mechanism by which MfpA and other PRP mediate antibiotic resistance and potentially regulate the enzymatic processing of DNA. MfpA will be developed as a model system for the exploration of DNA mimicry by this newly-discovered and widely-distributed class of proteins. Fluoroquinolones are extremely important antibiotics due to their efficacy against Gram- positive, Gram-negative and mycobacteria. Fluoroquinolones act on DNA gyrase with a unique mechanism of action. They are remarkable for their absence of toxicity and a therapeutic index that is the highest of all currently prescribed antibiotics. The rapid emergence, and spread, of transmissible forms of fluoroquinolone resistance due to the expression of the plasmid-encoded proteins threatens the clinical utility of these antibiotics. The proposed studies seek to understand how the physical properties of the Peptapeptide Repeat Proteins MfpA and Qnr generate resistance to fluoroquinolones. This understanding would provide new targets for therapeutics complementary to fluoroquinolone that would counter the PRP-mediated resistance. Conversely, an understanding of the mechanism by which these proteins function may allow the PRP fold to be used as a platform for the development of novel protein or peptide therapeutics.

描述(由申请人提供)：这项新提案的修订申请描述了对最近发现的五肽重复蛋白(PRP)家族成员的‘DNA模拟’进行的全面的生化和生物物理研究。结核分枝杆菌MFPA PRP的原子分辨结构显示了一个新的蛋白质折叠；MFPA的右旋双螺旋线圈产生了一个与DNA的大小、形状和静电表面非常相似的拉长结构。DNA模拟对MFPA的生物学作用很重要，它通过与DNA旋转酶结合从而抑制其功能而对氟喹诺酮类药物产生耐药性。我们将测试这一假设，即MFPA模仿DNA的物理性质是其赋予耐药性的能力的核心。我们的长期目标是了解MFPA和其他PRP介导抗生素耐药性的分子机制，并潜在地调节DNA的酶处理。MFPA将被开发为探索DNA模拟的模型系统，利用这一新发现的和广泛分布的蛋白质类别。氟喹诺酮类药物因其对革兰氏阳性菌、革兰氏阴性菌和分枝杆菌的有效作用而成为非常重要的抗菌药物。氟喹诺酮类药物通过独特的作用机制作用于DNA旋转酶。值得注意的是，它们没有毒性，治疗指数是目前所有处方抗生素中最高的。由于质粒编码蛋白的表达，可传播的氟喹诺酮耐药形式的迅速出现和传播威胁着这些抗生素的临床应用。这项拟议的研究试图了解多肽重复蛋白MFPA和QnR的物理性质如何产生对氟喹诺酮类药物的耐药性。这一认识将为补充氟喹诺酮类药物的治疗提供新的靶点，以对抗PRP介导的耐药性。相反，了解这些蛋白质的功能机制可能会使PRP折叠被用作开发新的蛋白质或多肽疗法的平台。

项目成果

Stability, denaturation and refolding of Mycobacterium tuberculosis MfpA, a DNA mimicking protein that confers antibiotic resistance.

结核分枝杆菌 MfpA（一种赋予抗生素抗性的 DNA 模拟蛋白）的稳定性、变性和重折叠。

• DOI: 10.1016/j.bpc.2011.04.015
• 发表时间: 2011
• 期刊: Biophysical chemistry
• 影响因子: 3.8
• 作者: Khrapunov,Sergei;Brenowitz,Michael
• 通讯作者: Brenowitz,Michael

Unusual characteristics of the DNA binding domain of epigenetic regulatory protein MeCP2 determine its binding specificity.

• DOI: 10.1021/bi500424z
• 发表时间: 2014-06-03
• 期刊: Biochemistry
• 影响因子: 2.9
• 作者: Khrapunov S;Warren C;Cheng H;Berko ER;Greally JM;Brenowitz M
• 通讯作者: Brenowitz M