Impact of charge state on 193 nm ultraviolet photodissociation of protein complexes

Abstract

Access to symmetric dissociation pathways is achieved using higher laser power for photodissociation of native-like protein complexes in the gas phase.

Higher-order structural characterisation of native proteins and complexes by top-down mass spectrometry

“…96 In contrast, 193 nm UVPD of several model protein complexes showed CID-like asymmetric dissociation at low pulse energy, but changed to more symmetric dissociation (SID-like) at higher pulse energy. 97,98 This change of dissociation behaviour as a function of input energy in UVPD is reminiscent of the mechanistic difference between the slow heating in CID and rapid heating in SID. Even though SID has been shown to induce dissociation of complexes with minimal unfolding, the monomer stripping pathway indicative of unfolding can also be observed in SID, especially for large protein complexes.…”

“…101 In addition to the differences in activation techniques, the charge of protein complexes is another important factor in complex-up experiments. 66,67,98,102 Charge reduction through solution additives and gas-phase reactions can supress protein unfolding, and generally help SID by increasing the percentage of structurally informative products. 66 In contrast, subunit dissociation is suppressed in CID for charge-reduced precursors.…”

The Ims Paradox: A Perspective on Structural Ion Mobility‐mass Spectrometry

“…Award Address (ACS Award in Analytical Chemistry sponsored by the Battelle Memorial Institute). Abstracts of Papers, 255th ACS National Meeting and Exposition, New Orleans, LA, United States, March 18–22, 2018, ANYL‐368) addressed this question using the diagram shown in Figure 1, where the major structure analysis techniques are compared in terms of “ease of use” and “information‐richness.” NMR, XRD, and cryo‐EM are capable of providing the highest resolution structural information; but when the complete suite of native MS/IM‐MS structural tools, for example, collision‐induced unfolding (CIU; Polasky et al, 2019), collisional‐induced dissociation (CID; Donor, Shepherd, & Prell, 2020), surface‐induced dissociation (SID; Zhou & Wysocki, 2014), ultraviolet photodissociation (UVPD; Sipe & Brodbelt, 2019), and infrared multiphoton dissociation (Pagel et al, 2009; Seo et al, 2017), are factored into the equation, native‐MS offers an unprecedented advantage in the field of structural biology.…”

Simple and Minimally Invasive SID Devices for Native Mass Spectrometry

“…Collision-induced dissociation of protein complexes produces restructured monomer in many cases and (n-1)mer with asymmetric charge partitioning but does not directly generate subcomplexes consistent with intersubunit connectivity. [14][15][16] Ultraviolet photodissociation 17 can result in production of subcomplexes in some cases, 18 but like infrared multiphoton dissociation 19 it is usually used to produce extensive sequence fragments. Surface-induced dissociation can create both sequence fragments (usually b/y ions from peptides) and subcomplexes (from protein complexes) that are consistent with protein quaternary structure.…”