Understanding the Thermal Denaturation of Myoglobin with IMS-MS: Evidence for Multiple Stable Structures and Trapped Pre-equilibrium States.

ABSTRACT: Thermal denaturation of holomyoglobin (hMb) in solution (10 mM ammonium acetate at pH = 4.5, 6.8, and 9.0) was monitored by ion mobility spectrometry (IMS) and mass spectrometry (MS) techniques to characterize the stability and investigate structural changes involved in unfolding. We utilize two experimental approaches to induce thermal denaturation: a variable-temperature electrospray ionization (vT-ESI) source that heats the bulk solution in the ESI emitter, and a variable-power 10.6 μm CO₂ laser that rapidly heats nanodroplets produced by ESI. These two approaches sample different time scales of the denaturation process; long time scales (seconds to minutes) where the system is at equilibrium using the vT-ESI approach and shorter time scales (μs) by rapid droplet heating in w

SUBMITTER: Woodall DW 

PROVIDER: S-EPMC7790998 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature