Reitsma, G. (2010) VUV and soft X-ray photoabsorption of gas phase protonated peptides. Master's Thesis / Essay, Physics.
|
Text
Phys_Ms_2010_G._Reitsma.pdf - Published Version Download (7MB) | Preview |
Abstract
The transport of biomolecules from space to early Earth could have had important consequences for the development of early life. Therefore, the stability of peptides upon VUV photon and soft X-ray interactions is of fundamental interest. In order to study these interactions, protonated peptides are produced by an electrospray ionization source and trapped in a three dimensional quadrupole in which they are exposed to synchrotron radiation. The obtained VUV photofragmentation spectra show different regimes of dissociation processes. Below ionization potential, the photon energy is mainly absorbed by the peptide bond, which leads to slow IVR governed processes. Above ionization threshold both fast dissociation through repulsive states and slow IVR dissociation processes can occur. The strongest observed peak is related to the fast loss of the tyrosine sidechain. Estimations of the internal energy show that the fast tyrosine sidechain loss efficiently cools the remaining peptide. It is conceivable that such cooling processes facilitate the survival of peptide substructures after photon absorption in space. Preliminary soft X-ray absorption induced fragment mass spectra recorded around the oxygen K-edge are presented. These spectra show the feasibility of a systematic study on the photostability of peptides under soft X-ray irradiation.
Item Type: | Thesis (Master's Thesis / Essay) |
---|---|
Degree programme: | Physics |
Thesis type: | Master's Thesis / Essay |
Language: | English |
Date Deposited: | 15 Feb 2018 07:45 |
Last Modified: | 15 Feb 2018 07:45 |
URI: | https://fse.studenttheses.ub.rug.nl/id/eprint/9541 |
Actions (login required)
View Item |