ABSTRACT
For protein analysis, both molecular biologists and mass spectrometrists desire an effective meld between gel electrophoresis and mass spectrometry (MS)
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[I ,21. Often, protein samples cannot be analyzed directly because they are impure or are insoluble (e.g., intrinsic membrane proteins or extracellular matrix proteins). Beyond its separation capabilities and ability to overcome the solubility problems of a broad range of proteins (e.g., by using sodium dodecyl sulfate [SDS] or urea gels), polyacrylamide gel electrophoresis (PAGE) allows parallel processing of either a large number of samples (by using one-dimensional [ 1-D] slab gels) or of a single, ultracomplex mixture (by using two-dimensional [2-D] gels). With the gargantuan volume of structural information being unearthed by genome and proteome projects, rapid methods must be developed to characterize the very large numbers of predicted protein products if the full benefits of these massive sequencing efforts are to be realized. Two-dimensional gel electrophoresis/mass spectrometry is poised to play an important role in this endeavor.
