Towards Gas-Phase Enzymes: Ion Chemistry for Introducing Selective Dissociation Pathways into Bio-ions
David J Foreman
10.25394/PGS.11881989.v1
https://hammer.purdue.edu/articles/thesis/Towards_Gas-Phase_Enzymes_Ion_Chemistry_for_Introducing_Selective_Dissociation_Pathways_into_Bio-ions/11881989
<p>Tandem mass spectrometry has long
been used as a tool to extract structural information from an analyte ion.
However, the information obtained in a tandem mass spectrometry experiment is
dependent on both the ion type subjected to activation and the type of
dissociation method used. Several activation methods, including electron
capture dissociation (ECD), electron transfer dissociation (ETD), and
ultraviolet photodissociation (UVPD) have emerged with a common objective to
maximize the number of sequence informative product ions. There is merit,
though, in mass spectrometry-based approaches which maximize selective
cleavages, serving to concentrate product ion signal into relatively few
fragmentation channels or to introduce a weak-spot into a peptide or protein.
Ion/ion reactions can be used as a means to transform peptide and protein ions
to new ion types which demonstrate highly selective fragmentation channels.
Here, the utility of introducing selective cleavages via ion/ion reactions is
demonstrated. In one example, a series of proton transfer ion/ion reactions are
utilized to concentrate and move the precursor ion signal into a mass-to-charge
region most likely to maximize cleavages at aspartic acid and proline, aiding
in low abundance protein identification. In another example, various types of
ion/ion reactions are utilized to unambiguously sequence cyclic peptides in the
gas-phase.</p>
2020-02-24 13:12:34
Ion/ion reactions
mass spectrometry
Analytical Chemistry not elsewhere classified
Proteins and Peptides