TANDEM MASS SPECTROMETRY FOR ASSESSING DNA DAMAGE

用于评估 DNA 损伤的串联质谱法

• 批准号: 6602696
• 负责人: MICHAEL L GROSS
• 金额: $ 16.87万
• 依托单位: UNIVERSITY OF NEBRASKA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-07-01 至 2003-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6602696
• 关键词: DNA damage; adduct; carbopolycyclic compound; chemical conjugate; electrospray ionization mass spectrometry; estrogens; liquid chromatography mass spectrometry; matrix assisted laser desorption ionization; oligonucleotides

A unifying goal for this research is to understand the mechanisms of fragmentations so that interpretations of production-ion spectra can be placed on a firm foundation. Therefore, the first aim is to evaluate various spectrometry methods to distinguish isomeric adducts and potential biomarkers. New to our effort will be a major activity to understand isomerically distinct fragmentations by using molecular orbital calculations. Six classes of fragmentations are identified for study on the basis of our experience in this area. In parallel with developing an understanding of ion chemistry, we will develop and validate electrospray liquid chromatography (LC/MS) and LC-tandem-MS methods for the trace determination of estrogen metabolites, conjugates, and nucleobase adducts. We are proposing two approaches: a low-throughput method that posses maximal certainty for identification of analytes and a high- throughput method for rapid screening of tissues. These methods will then be used to support research in other subprojects. Emphasis will be on analysis of tissues for estrogen biomarkers and on biological fluids for polycyclic aromatic hydrocarbon (PAH) adducts. We will also emphasize a biophysical aspect of MS in which the instrumentation is used to evaluate the binding of carcinogens to DNA by investigating non- covalent complexes of small duplex oligodeoxynucleotides and estrogens or PAH. Following the study of interactions, we focus on the modification reactions themselves by devising and utilizing MS methods for following directly the reactions of carcinogens with model single and double-stranded oligonucleotides. Sufficient preliminary results support the launch of these latter, relatively new projects.

这项研究的一个统一的目标是了解碎片化的机制，使生产离子光谱的解释可以放在一个坚实的基础上。因此，首要的目标是评估各种光谱方法来区分异构加合物和潜在的生物标志物。新的我们的努力将是一个主要的活动，以了解异构不同的碎片，通过使用分子轨道计算。根据我们在这一领域的经验，确定了六类碎片化研究。在发展离子化学的理解的同时，我们将开发和验证电喷雾液相色谱法（LC/MS）和LC-串联-MS方法，用于痕量测定雌激素代谢物，共轭物和核碱基加合物。我们提出了两种方法：一种低通量的方法，最大限度地确定分析物的鉴定和高通量的方法，用于快速筛选组织。这些方法将用于支持其他子项目的研究。重点将放在雌激素生物标志物的组织分析和多环芳烃（PAH）加合物的生物液体上。我们还将强调MS的生物物理学方面，其中仪器用于通过研究小双链寡脱氧核苷酸和雌激素或PAH的非共价复合物来评估致癌物与DNA的结合。在相互作用的研究之后，我们专注于通过设计和利用MS方法直接跟踪致癌物与模型单链和双链寡核苷酸的反应的修饰反应本身。有足够的初步结果支持启动这些较新的项目。