Protein complexes and analysis of their assembly by mass spectrometry.

The utility of mass spectrometry for the analysis of proteins has grown enormously in the past decade. Significant advances in detection and ionization techniques are allowing questions about noncovalent assembly to be addressed by the direct observation of gas phase complexes, their assembly in real time and their disassembly by perturbation of solution or instrument conditions. These technological innovations have plainly captured the imagination of biological researchers. Recent and novel developments include the combination of mass spectrometry with isotopic labeling, affinity labeling and genomic information. Collectively, these advances are opening new doors to the isolation of complexes, the identification of their substituents and the characterization of their conformations and assembly.