COOA--A COSENSING TRANSCRIPTIONAL ACTIVATOR

COOA--共感转录激活剂

• 批准号: 6138323
• 负责人: MARC V THORSTEINSSON
• 金额: $ 3.24万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-01-01 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6138323
• 关键词: Raman spectrometry; Rhodospirillum; bacterial genetics; biological signal transduction; carbon monoxide; chemical binding; electron spin resonance spectroscopy; gene mutation; heme; microorganism metabolism; transcription factor

CooA is a transcriptional regulator that senses carbon monoxide (CO) through a heme moiety and activates the transcription of the coo regulon, whose gene products are required for the oxidation of CO in Rhodospirillium rubrum. Preliminary work suggests a low-spin, hexacoordinate heme structure in the ferric, ferrous, and CO-ferrous forms of CooA, suggesting that a protein ligand is displaced upon CO binding. The precise mechanism of signal transduction within CooA upon CO binding is currently unknown. In order to address this question, the proposal describes the creation and characterization of functionally important variants of CooA that show an altered response to CO and the potential effectors nitric oxide and cyanide, is proposed. Functionally interesting CooA variants will be isolated and characterized by standard spectroscopies in order to interpret the effects of perturbation of the proposed heme-binding pocket of CooA. The study proposed will produce information concerning the interpretation of the CO signal by CooA and how this event is coupled to DNA binding by conformational changes within the protein. Characterization f mutants that demonstrate atypical responses to effectors will provide an understanding of CooA function and insights concerning small molecule sensing and discrimination by proteins.

COOA是一种转录调节剂，通过血红素部分感知一氧化碳（CO），并激活COO调节量的转录，COO调节剂的转录是其基因产物在Rohodospirillium rubrum中氧化所必需的。 初步工作表明，在铁的铁，亚铁和共有形式中，低自旋，六角形的血红素结构表明蛋白质配体在CO结合后会取代。 当前未知COOA内COOA内信号转导的精确机制。为了解决这个问题，该提案描述了COOA功能上重要的变体的创建和表征，这些变体显示了对CO的反应改变，并且提出了潜在的效应子一氧化氮和氰化物。 功能上有趣的COOA变体将以标准光谱镜来隔离和特征，以解释COOA所提出的血红素结合口袋的扰动的影响。 提出的研究将产生有关COOA解释CO信号的信息，以及该事件如何通过蛋白质内构象变化耦合到DNA结合。 表现出对效应子的非典型反应的表征F突变体将提供对cOOA功能的理解以及有关蛋白质的小分子传感和歧视的见解。