Conformation types of ubiquitin [M+8H]8+ Ions from water:methanol solutions: evidence for the N and A States in aqueous solution.

ABSTRACT: Ion mobility and mass spectrometry measurements are used to examine the gas-phase populations of [M+8H](8+) ubiquitin ions formed upon electrospraying 20 different solutions from 100:0 to 5:95 water:methanol that are maintained at pH = 2.0. Over this range of solution conditions, mobility distributions for the +8 charge state show substantial variations. Here we develop a model that treats the combined measurements as one data set. By varying the relative abundances of a discrete set of conformation types, it is possible to represent distributions obtained from any solution. For solutions that favor the well-known A-state ubiquitin, it is possible to represent the gas-phase distributions with seven conformation types. Aqueous conditions that favor the native structure require four more str

SUBMITTER: Shi H 

PROVIDER: S-EPMC3351143 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature