Hemoglobin I From Lucina Pectinata: A Model for Hydrogen Sulfide Reactivity Within Hemeproteins

Lucina Pectinata 中的血红蛋白 I：血红素蛋白内硫化氢反应性的模型

• 批准号: 0544250
• 负责人: Juan Lopez-Garriga
• 金额: --
• 依托单位: University of Puerto Rico Mayaguez
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-01-01 至 2009-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0544250&HistoricalAwards=false
• 关键词: Hemoglobin; Lucina; Pectinata; Model; Hydrogen

The tropical clam Lucina pectinata lives in sulfide-rich environments and is characterized by the presence of symbiotic sulfide-oxidizing bacteria that need to be supplied with both H2S and O2. The biological molecule responsible for delivering H2S to the bacteria is a heme protein called hemoglobin I (HbI). HbI is one of the few known H2S carriers in organisms that have been implicated in physiologically binding this molecule in the ferric heme iron center so as to maintain the symbiotic relationship with the bacteria as well as to protect the clam from H2S toxicity. A thorough understanding of the association, stabilization, and dissociation mechanism of the physiological relevant H2S ligand with HbI and other heme proteins has not been established yet. In this project, the relationship between structure and reactivity of the HbI-H2S complex will be investigated to define how the chemical nature of the amino acids in the heme pocket affects H2S binding and hydrogen bonding interactions in heme proteins. A combination of molecular biology and biophysical techniques will be used. In addition, correlations of HbI-H2S NMR chemical shifts and EXAFS distances of the HbI-H2S moiety will be examined. The intellectual merits of the project are to determine the structure, dynamics, and reactivity of H2S and HbI and to understand the mechanism of H2S release by the hemoglobin to the symbiotic bacteria. Understanding the biophysical basis H2S transport by HbI could help in the future developments of a biosensor to detect H2S in ecological and biological environments; H2S is a known toxic compound.Broader Impacts: This interdisciplinary project will be used as teaching tools to mentor graduate and undergraduate students and to increase their knowledge and communication abilities to express research results to society. Consequently, the broader impacts to society are inherent to increasing the number of well-trained students capable of fully achieving their academic or industrial career. The project will also enhance outreach to pre-college students and teachers through the GK-12 program.

热带蛤Lucina pectinata生活在富含硫化物的环境中，其特点是共生硫化物氧化细菌的存在，需要H2S和O2的供应。负责向细菌输送H2S的生物分子是一种叫做血红蛋白I （HbI）的血红素蛋白。HbI是生物体内为数不多的已知H2S载体之一，它们与该分子在铁血红素铁中心的生理结合，从而维持与细菌的共生关系，并保护蛤免受H2S毒性。生理相关的H2S配体与HbI及其他血红素蛋白的结合、稳定和解离机制尚未完全了解。在本项目中，将研究HbI-H2S复合物的结构与反应性之间的关系，以确定血红素口袋中氨基酸的化学性质如何影响血红素蛋白中H2S结合和氢键相互作用。将使用分子生物学和生物物理技术的结合。此外，HbI-H2S核磁共振化学位移和HbI-H2S部分的EXAFS距离的相关性将被检查。该项目的智力优势在于确定H2S和HbI的结构、动力学和反应性，并了解血红蛋白向共生细菌释放H2S的机制。了解H2S通过HbI传输的生物物理基础，有助于未来开发生物传感器来检测生态和生物环境中的H2S；H2S是一种已知的有毒化合物。更广泛的影响：这个跨学科的项目将作为教学工具来指导研究生和本科生，增加他们的知识和沟通能力，向社会表达研究成果。因此，增加训练有素的学生的数量，使他们能够充分实现他们的学术或工业生涯，对社会产生更广泛的影响。该项目还将通过GK-12计划加强对大学预科学生和教师的宣传。