Mass spectrometry combined with oxidative labeling for exploring protein structure and folding.
This review discusses various mass spectrometry (MS)-based approaches for exploring structural aspects of proteins in solution. Electrospray ionization (ESI)-MS, in particular, has found fascinating applications in this area. For example, when used in conjunction with solution-phase hydrogen/deuterium exchange (HDX), ESI-MS is a highly sensitive tool for probing conformational dynamics. The main focus of this article is a technique that is complementary to HDX, that is, the covalent labeling of proteins by hydroxyl radicals. The reactivity of individual amino acid side chains with *OH is strongly affected by their degree of solvent exposure. Thus, analysis of the oxidative labeling pattern by peptide mapping and tandem mass spectrometry provides detailed structural information. A convenient method for *OH production is the photolysis of H(2)O(2) by a pulsed UV laser, resulting in oxidative labeling on the microsecond time scale. Selected examples demonstrate the use of this technique for structural studies on membrane proteins, and the combination with rapid mixing devices for characterizing the properties of short-lived protein (un)folding intermediates.
Konermann
Lars
L
Department of Chemistry, The University of Western Ontario, London, Ontario, Canada N6A 5B7. konerman@uwo.ca
Stocks
Bradley B
BB
Pan
Yan
Y
Tong
Xin
X
D000596:Amino Acids / Q000737:chemistry; D001436:Bacteriorhodopsins / Q000737:chemistry; D002942:Circular Dichroism; D003903:Deuterium; D006859:Hydrogen; D017665:Hydroxyl Radical / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods*; D008958:Models, Molecular; D015394:Molecular Structure; D009211:Myoglobin / Q000737:chemistry; D010084:Oxidation-Reduction; D011485:Protein Binding; D017510:Protein Folding; D011506:Proteins / Q000737:chemistry* / Q000378:metabolism; D021241:Spectrometry, Mass, Electrospray Ionization
D000596:Amino Acids; D009211:Myoglobin; D011506:Proteins; D017665:Hydroxyl Radical; D001436:Bacteriorhodopsins; D006859:Hydrogen; D003903:Deuterium