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Characterization of Conformational Ensembles of Protonated N-glycans in the Gas-Phase.

ABSTRACT: Ion mobility mass spectrometry (IM-MS) is a technique capable of investigating structural changes of biomolecules based on their collision cross section (CCS). Recent advances in IM-MS allow us to separate carbohydrate isomers with subtle conformational differences, but the relationship between CCS and atomic structure remains elusive. Here, we characterize conformational ensembles of gas-phase N-glycans under the electrospray ionization condition using molecular dynamics simulations with enhanced sampling. We show that the separation of CCSs between isomers reflects folding features of N-glycans, which are determined both by chemical compositions and protonation states. Providing a physicochemical basis of CCS for N-glycans helps not only to interpret IM-MS measurements but also to estimate CCSs of complex glycans.

SUBMITTER: Re S

PROVIDER: S-EPMC5786100 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Characterization of Conformational Ensembles of Protonated N-glycans in the Gas-Phase.

Re Suyong S Watabe Shigehisa S Nishima Wataru W Muneyuki Eiro E Yamaguchi Yoshiki Y MacKerell Alexander D AD Sugita Yuji Y

Scientific reports 20180126 1

Ion mobility mass spectrometry (IM-MS) is a technique capable of investigating structural changes of biomolecules based on their collision cross section (CCS). Recent advances in IM-MS allow us to separate carbohydrate isomers with subtle conformational differences, but the relationship between CCS and atomic structure remains elusive. Here, we characterize conformational ensembles of gas-phase N-glycans under the electrospray ionization condition using molecular dynamics simulations with enhanc ...[more]

PMID: 29374210

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