Wall Daniel B, Berger Scott J, Finch Jeffrey W, Cohen Steven A, Richardson Keith, Chapman Richard, Drabble Darren, Brown Jeffery, Gostick Dominic
Waters Corporation, Milford, MA 01757, USA.
Electrophoresis. 2002 Sep;23(18):3193-204. doi: 10.1002/1522-2683(200209)23:18<3193::AID-ELPS3193>3.0.CO;2-Y.
Peptide mass fingerprinting by matrix-assisted laser desorption/ionization (MALDI)-mass spectrometry (MS) is one of the standard high-throughput methods for protein identification today. Traditionally this method has been based on spotting peptide mixtures onto MALDI targets. While this method works well for more abundant proteins, low-abundance proteins mixed with high-abundance proteins tend to go undetected due to ion suppression effects, instrumental dynamic range limitations and chemical noise interference. We present an alternative approach where liquid chromatography (LC) effluent is continuously collected as linear tracks on a MALDI target. In this manner the chromatographic separation is spatially preserved on the target, which enables generation of off-line LC-MS and LC-MS/MS data by MALDI. LC-MALDI sample collection provides improved sensitivity and dynamic range, spatial resolution of peptides along the sample track, and permits peptide mass mapping of low-abundance proteins in mixtures containing high-abundance proteins. In this work, standard and ribosomal protein digests are resolved and captured using LC-MALDI sample collection and analyzed by MALDI-TOF-MS.
通过基质辅助激光解吸/电离(MALDI)质谱(MS)进行肽质量指纹图谱分析是当今蛋白质鉴定的标准高通量方法之一。传统上,该方法基于将肽混合物点样到MALDI靶板上。虽然这种方法对于丰度较高的蛋白质效果良好,但由于离子抑制效应、仪器动态范围限制和化学噪声干扰,与高丰度蛋白质混合的低丰度蛋白质往往难以检测到。我们提出了一种替代方法,即液相色谱(LC)流出物在MALDI靶板上作为线性轨迹连续收集。通过这种方式,色谱分离在靶板上得以空间保留,从而能够通过MALDI生成离线LC-MS和LC-MS/MS数据。LC-MALDI样品收集提高了灵敏度和动态范围,沿样品轨迹实现了肽的空间分辨率,并允许对含有高丰度蛋白质的混合物中的低丰度蛋白质进行肽质量图谱分析。在这项工作中,使用LC-MALDI样品收集对标准蛋白和核糖体蛋白消化产物进行分离和捕获,并通过MALDI-TOF-MS进行分析。