Wydział Chemii

Monika Kijewska

Dorota Gąszczyk

Remigiusz Bąchor

Piotr Stefanowicz

Zbigniew Szewczuk

2021

Molecules

26

6964/1-6964/23

10.3390/molecules26226964

Naukowa

Angielski

Artykuł

Peptide modification by a quaternary ammonium group containing a permanent positive charge is a promising method of increasing the ionization efficiency of the analyzed compounds, making ultra-sensitive detection even at the attomolar level possible. Charge-derivatized peptides may undergo both charge remote (ChR) and charge-directed (ChD) fragmentation. A series of model peptide conjugates derivatized with N,N,N-triethyloammonium (TEA), 1-azoniabicyclo[2.2.2]octane (ABCO), 2,4,6-triphenylopyridinium (TPP) and tris(2,4,6-trimetoxyphenylo)phosphonium (TMPP) groups were analyzed by their fragmentation pathways both in collision-induced dissociation (CID) and electron-capture dissociation (ECD) mode. The effect of the fixed-charge tag type and peptide sequence on the fragmentation pathways was investigated. We found that the aspartic acid effect plays a crucial role in the CID fragmentation of TPP and TEA peptide conjugates whereas it was not resolved for the peptides derivatized with the phosphonium group. ECD spectra are mostly dominated by c_n ions. ECD fragmentation of TMPP-modified peptides results in the formation of intense fragments derived from this fixed-charge tag, which may serve as reporter ion.

derivatization, fixed charge tag, quaternary ammonium salt, mass spectrometry, electron-capture dissociation, collision induced dissociation

CC-BY

http://dx.doi.org/10.3390/molecules26226964

http://www.mdpi.com/journal/metals