| Autor: |
Ethan R. Badman, Sharon J. Pitteri, Scott A. McLuckey, Paul A. Chrisman |
| Rok vydání: |
2006 |
| Předmět: |
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| Zdroj: |
International Journal of Mass Spectrometry. 253:147-155 |
| ISSN: |
1387-3806 |
| DOI: |
10.1016/j.ijms.2005.11.028 |
| Popis: |
Ion trap collision-induced dissociation (CID) of a non-covalent complex formed between porcine trypsin and bovine pancreatic trypsin inhibitor (BPTI) has been studied for charge states +10 to +5. Fragmentation of the +10 and +9 complexes formed directly from solution shows separation of the two subunits as the predominant dissociation channel. Lower charge states of the complex were formed by ion/ion (or, in one case, ion/molecule) proton transfer reactions. The +8 complex shows a mixture of fragmentation behavior, including subunit separation and losses of small neutral and charged species. The neutral loss is also a dominant pathway for the +7 to +5 charge states and the loss of a small cation is also common to the +7 and +6 charge states. The identity of the small cation lost was investigated and is likely to be the b 2 + ion from the BPTI subunit. This identification was supported by examination of fragmentation of various charge states of BPTI cations and a “fast” collisional activation experiment performed on the +7 complex. These results suggest that precursor ion charge state can play a dramatic role in the gas phase dissociation of protein–protein complexes such that covalent bond dissociation can come to dominate over subunit separation when Coulombic repulsion is decreased. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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Full Text from ScienceDirect