INFLUENCE OF AA SUBSTITUTIONS ON STABILITY OF TETRAMER-DIMER INTERFACE OF HBS

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 曼宁教授在东北大学的实验室和我们的实验室之间仍在进行着一项持续而富有成效的合作。这项合作奋进的实验目标是通过质谱法对人血红蛋白多肽链中天然存在的或基因工程改造的突变进行完整表征。最近，我们的实验室开始与J. Eric Russell教授的实验室合作，研究转基因小鼠中产生的胚胎血红蛋白。我们的研究旨在更好地了解血红蛋白四聚体内的长距离通信，这会影响氧气运输到外周组织的效率。我们目前正在研究人类血红蛋白的四聚体-二聚体界面附近的某些氨基酸残基的关系。质谱法被用于使用三步法表征血红蛋白中的组成多肽链，该三步法包括（1）通过电喷雾电离质谱法分析多肽链的完整质量;（2）用特异性蛋白酶消化多肽链并通过MALDI-TOF/MS获得肽图;和（3）在电喷雾电离离子阱质谱仪上通过质谱片段化对含有突变的肽进行测序。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. An ongoing and productive collaboration is still in progress between Prof. Manning's laboratory at Northeastern University and ours. The experimental goal of this collaborative endeavor is at the complete characterization by mass spectrometry of either naturally occurring or genetically engineered mutations in the polypeptide chains of human hemoglobins. Recently, our laboratories began a project with Prof. J. Eric Russell's laboratory to study embryonic hemoglobins produced in transgenic mice. Our studies aim at a better understanding of the long-range communications within hemoglobin tetramers which affect the efficiency of the oxygen transport to peripheral tissues. We are currently investigating the relationship of certain amino acid residues near the tetramer-dimer interface of human hemoglobin. Mass spectrometry is being used to characterize the constituting polypeptide chains in hemoglobin using a three-step approach that consists in (1) analyzing the intact mass of the polypeptide chains by electrospray ionization mass spectrometry; (2) digesting the polypeptide chains with a specific proteinase and obtaining peptide maps by MALDI-TOF/MS; and (3) sequencing the peptides containing the mutations by mass spectrometric fragmentation on an electrospray ionization ion trap mass spectrometer.