Electrospray ionization-mass spectrometry characterization of heterotetrameric sarcosine oxidase.
Electrospray ionization-mass spectrometry characterization of heterotetrameric sarcosine oxidase.
复制标题
异四聚体肌氨酸氧化酶的电喷雾电离质谱表征。
DOI：
10.1016/s1044-0305(98)00011-7
复制
发表时间：
1998
影响因子：
3.2
通讯作者：
Jorns,MS
中科院分区：
文献类型：
--
作者：
PasaTolić,L;Harms,AC;Anderson,GA;Smith,RD;Willie,A;Jorns,MS
电喷雾电离（ESI）傅立叶变换离子回旋共振（FTICR）质谱已被用来表征异源四聚体棒状杆菌肌氨酸氧化酶。通过使用常规的四极质谱仪，不能获得完整复合物的光谱（即，在中性pH下电喷雾蛋白质），但当从酸性溶液电喷雾时获得显示四种蛋白质亚基的光谱。完整的异源四聚体的初始低分辨率ESI-FTICR质谱显示在6000 < m/z < 9000范围内的典型窄电荷态分布，与气相中的致密结构的保留一致，并且给出比预测高约1000 u的质量测量。有效的阱内清理，基于低能量碰撞诱导解离的加合物，允许显着提高质量测量精度。本结果代表了使用FTICR质谱法成功分析的最大的异源多聚体蛋白复合物，并清楚地说明了样品清洁方法对大分子表征的重要性。
Electrospray ionization (ESI) Fourier transform ion cyclotron resonance (FTICR) mass spectrometry has been used to characterize heterotetrameric corynebacterial sarcosine oxidase. By using a conventional quadrupole mass spectrometer, no spectra for the intact complex could be obtained (i.e., electrospraying protein at neutral pH), but spectra showing the four protein subunits were obtained when electrospraying from acidic solution. Initial low resolution ESI-FTICR mass spectra of the intact heterotetramer revealed a typical narrow charge state distribution in the range 6000 < m/z < 9000, consistent with retention of a compact structure in the gas phase, and gave a mass measurement about 1000 u higher than predicted. Efficient in-trap clean up, based upon low energy collisionally induced dissociation of adducts, allowed significant improvement in mass measurement accuracy. The present results represent the largest heteromultimeric protein complex successfully analyzed using FTICR mass spectrometry, and clearly illustrate the importance of sample clean up methods for large molecule characterization.