Abstract
With the development of soft ionization techniques and the advances in instruments, mass spectrometry has come to be an essential tool for the characterization of proteins. It has been used successfully for the investigation of the amino acid sequences of large macromolecules, such as IgG. In addition, it is effective for the characterization of post-translational modifications of proteins.
The tertiary structure of proteins has generally been investigated using X-ray crystallography and NMR. Precise information on the tertiary structure can be obtained by these techniques. However, these analyses are time consuming and require a large scale sample preparation. Accordingly, it is impossible to apply these methods directly to a small amount of proteins derived from the living organisms. On the other hand, mass spectrometry requires only a small amount of sample, such as several pico-mole, for the determination of the molecular weight of a protein and/or a peptide in a routine analysis. Consequently, studies on the tertiary structure and/or the surface structure of the protein molecules have come to be carried out by mass spectrometry, in order to characterize the tertiary and/or surface structure of the protein with a small amount of sample.
This paper discusses the characterization not only of the primary structure but also of the tertiary structure of proteins by mass spectrometry.
