Abstract

Recent Developments of Electrospray Ionization Mass Spectrometry in the Study of Sequence and Structures of Biological Macromolecules

Shyamalava Mazumdar, Senior Professor, Tata Institute of Fundamental Research

The Electrospray Ionization (ESI) has emerged as an important technique for mass spectrometric studies of large, non-volatile compounds. This soft ionization technique is extensively used for production of gas phase ions of thermally labile macromolecules without causing any significant fragmentation. There have been extensive studies on the mechanism of formation of charged gaseous species by the ESI. Several groups, including us have investigated the origin and implications of the multiple charge states observed in the ESI-mass spectra of the peptides and proteins. The charged analytes produced by this technique can be selectively fragmented by activating them in the gas-phase. This has led to the development of tandem mass spectrometric techniques, to derive important insights on the structural properties of the macromolecule. Tandem mass spectrometric methods are used for sequence identification of peptides. We have discovered novel methods to identify isobaric amino acids, such as lysine and glutamine in a peptide, which was difficult to differentiate earlier. The talk will highlight recent developments and emerging directions in this fascinating area of research.