Collision-induced and surface-induced dissociation of protonated tri- and tetraalanine ((AAA)H+ and (AAAA)H+) were studied using a 7 T Fourier Transform Ion Cyclotron Resonance Mass Spectrometer (FT-ICR MS). Energy-resolved fragmentation efficiency curves obtained using both techniques were modeled using RRKM/QET formalism. The stability of small polyalanines decreases with increasing peptide size. The major reaction channels of protonated di- tri-and tetraalanine have dissociation thresholds of 2.11 eV, 1.46 eV and 1.23 eV, respectively. The rates of formation of C-terminal and N-terminal fragments from protonated tetraalanine are the same, while C-terminal fragmentation of trialanine is energetically more demanding than N-terminal fragmentation.
Revised: August 4, 2010 |
Published: August 1, 2002
Citation
Laskin J., E.V. Denisov, and J.H. Futrell. 2002.Fragmentation Energetics of Small Peptides from Multiple-Collision Activation and Surface-Induced Dissociation in FT-ICR MS.International Journal of Mass Spectrometry 219, no. 1:189-201.PNNL-SA-35101.