Photodissociation Mass Spectrometry of Peptides and Proteins

Abstract

Photodissociation has been extensively explored in the last decades for the analysis of peptides and proteins by mass spectrometry (MS). In the photodissociation process, ions interact with photons generating an increment on internal energy that leads to their fragmentation. The specific characteristics of photodissociation techniques have led to improvements in different applications of MS. Among them, the cleavage of molecular bonds in a selective manner, based on the incorporation of chromophore molecules. Moreover, the ability to generate an almost complete array of fragment ions is the main reason for the increment in the utilization of ultraviolet photodissociation (UVPD). This technique has been applied to the most challenging proteomics studies, such as the characterization of posttranslational modifications and protein sequence variations, de novo sequencing, and the analysis of intact proteins. This article is focused on the most recent and relevant developments of infrared photodissociation and UVPD techniques and their application to the study of peptides and proteins.

Ion‐molecule reactions of mass‐selected ions

“…Another facet of IMR applications involve hydrogen/deuterium exchange (HDX). Gas‐phase HDX has shown promise for structural property elucidation of protein mutations and the effect they have in biology and medicine (Gajiwala et al, 2009; Zhang et al, 2011), peptides (Julia & de Oliveira, 2006), and carbohydrates with several different instrumental set ups. Several reviews have been written in recent years covering advances in solution phase and computational methods involving HDX (Chipuk & Brodbelt, 2016).…”

What's all the phos about? Insights into the phosphorylation state of the RNA polymerase II C-terminal domainviamass spectrometry

“…ETD is also prone to non-dissociative events where peptide fragments are held together through non-covalent interactions after electron transfer. 14,[24][25][26][27][28][29][30] Thus, new methods have emerged where supplemental energy is added via IR-heating or collisional activation to enhance the separation of non-covalently linked products into diagnostic fragment ions. 31,32 Another type of ion activation method called photodissociation (PD) uses photon absorption for energy.…”