MICROMASS HYBRID QUADRUPOLE--TOF MASS SPECTROMETER

本申请的主要目的是购买混合四极杆正交飞行时间质谱仪（Q-tof）。UAB研究人员进行的研究工作中越来越多的是鉴定介导特定细胞功能（信号传导，细胞形状，细胞运动等）的蛋白质的生化或化学修饰形式。在单个细胞系和病变组织中。Q-tof的增加的灵敏度将允许检查蛋白质的内源性翻译后修饰。化学修饰可能是有意的（用于研究结构或机制假设的探针），也可能是间接的（在治疗药物、其代谢物或其他外源性物质的作用中）。这些将包括氢氘交换实验，使蛋白质折叠和蛋白质-蛋白质相互作用的研究。在许多情况下，可用于分析的蛋白质和/或其蛋白水解肽的量是严格限制的（中飞摩尔范围），比质谱共享设施中现有质谱仪或任何化学测序方法可检测的量少10-100倍。Q-TOF仪器通过将四极离子选择与离子碎裂和飞行时间分析仪相结合，提供了解决这些问题所需的灵敏度增加。在相关应用中，研究人员将利用Q-tof的更宽m/z范围（0- 8，000）来研究蛋白质分子离子的较低电荷状态。这可能是（1）特定蛋白质的氨基酸组成，92）在神经pH值下进行电喷雾实验，或（3）在蛋白质-蛋白质和蛋白质-DNA结合研究期间的结果。总之，Micromass Q-tof质谱仪将大大提高UAB教职员工进行NIH资助的生物医学研究的能力。

The principal purpose of this application is the purchase of a hybrid quadrupole-orthogonal time-of-flight mass spectrometer (Q-tof). An increasing part of th research effort conducted by UAB investigators is identification of the biochemically or chemically modified forms of proteins mediating specific cellular functions (signalling, cell shape, cell motility, etc.) in individual cell lines and in diseased tissues. The increased sensitivity of the Q-tof will allow endogenous, post- translational modifications of proteins to be examined. Chemical modifications may be deliberate (probes to investigate structural or mechanistic hypotheses) or consequential (in the action of a therapeutic drug, one of its metabolites, or other xenobiotics). These will include hydrogen-deuterium exchange experiments which enable the study of protein folding and protein-protein interactions. In many cases, the amounts of the proteins and/or their proteolytic peptides available for analysis is strictly limited (mid-femtomole range), 10-100 times less than can be detected by the existing mass spectrometers in the Mass Spectrometry Shared Facility, or by any chemical sequencing method. The Q-tof instrument, by combining quadrupole ion selection with ion fragmentation and a time-of-flight analyzer, provides the necessary increase in sensitivity to attack these problems. In related applications, investigators will take advantage of the wider m/z range (0-8,000) of the Q-tof to study lower charge states of molecular ions of proteins. This may be a consequence of (1) the amino acid composition of a particular protein, 92) carrying out electrospray experiments at neural pH, or (3) during the study of protein-protein and protein-DNA binding. In summary, the Micromass Q-tof mass spectrometer will substantially enhance the capability of a wide range of UAB faculty carrying our NIH-funded biomedical research.