Correction: Conformational changes in amyloid-beta (12–28) alloforms studied using action-FRET, IMS and molecular dynamics simulations

Abstract

Correction for ‘Conformational changes in amyloid-beta (12–28) alloforms studied using action-FRET, IMS and molecular dynamics simulations’ by Steven Daly et al., Chem. Sci., 2015, 6, 5040–5047.

Conformational assignment of gas phase peptides and their H-bonded complexes using far-IR/THz: IR-UV ion dip experiment, DFT-MD spectroscopy, and graph theory for mode assignment

“…See for instance refs. 11,24,[37][38][39] for reviews on spectroscopy/ion mobility couplings. Another option, that we follow in the present work, is to probe lower frequency modes and hence gain new and less congested spectral information, that will lead to the removal of structural ambiguities.…”

Ion mobility-mass spectrometry and orthogonal gas-phase techniques to study amyloid formation and inhibition

“…At charge states 3+ and 4+ Aβ 12-18 adopts a predominantly helical conformation, whereas additional protonation (5+/6+) leads to a structural transition into a β-turn. [39] Such charge-dependent conformations are also observed for other proteins in the gas phase. [40,41] Generally, species with a higher charge state form extended structures because Coulomb repulsion and interactions of charged side-chains with backbone carbonyls alter the native fold.…”

“…[18,34] More importantly, also a direct coupling to orthogonal gas-phase techniques can be performed to obtain more detailed structural information. Very recently, IM-MS was for example used as a pre-selection tool to perform gas phase IR [38] or FRET [39] spectroscopy. These experiments led to new insights into the secondary structure of early amyloid intermediates, and it is likely that similar experiments will in the future be applied to study larger amyloid forming systems such as hIAPP and Aβ as well as the binding mode of inhibitors.…”

“…they are at least partly folded and therefore exchange slower, are more cytotoxic than aggregates, which rapidly undergo HDX. In addition, a hydroxyl radical-based, fast photochemical oxidation approach indicates that Aβ42-fibril formation is predominantly driven by the central hydrophobic core (16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27) as well as the C-terminus (28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42), whereas the N-terminus remains almost unstructured [35].…”

Adding a new separation dimension to MS and LC–MS: What is the utility of ion mobility spectrometry?

“…IM–MS provides valuable data on the ion's overall size and shape, but it does not yield direct information about the underlying internal structure. To obtain such data, IM–MS was recently used as a preselection tool for a further analysis using orthogonal, structure‐sensitive gas‐phase techniques, like action fluorescence resonance energy transfer spectroscopy , or gas phase IR spectroscopy . IM–MS can also be successfully applied for high‐throughput inhibitor screening.…”