Anharmonic behavior in the multisubunit protein apoferritin as revealed by quasi-elastic neutron scattering

M. T F Telling, Cameron Neylon, Susan H. Kilcoyne, Valeria Arrighi

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

Quasi-elastic neutron scattering (QENS) has been used to study the deviation from Debye-law harmonic behavior in lyophilized and hydrated apoferritin, a naturally occurring, multisubunit protein. Whereas analysis of the measured mean squared displacement (msd) parameter reveals a hydration-dependent inflection above 240 K, characteristic of diffusive motion, a hydration-independent inflection is observed at 100 K. The mechanism responsible for this low-temperature anharmonic response is further investigated, via analysis of the elastic incoherent neutron scattering intensity, by applying models developed to describe side-group motion in glassy polymers. Our results suggest that the deviation from harmonic behavior is due to the onset of methyl group rotations which exhibit a broad distribution of activated processes (Ea,ave = 12.2 kJ· mol-1, s = 5.0 kJ·mol-1). Our results are likened to those reported for other proteins. © 2008 American Chemical Society.

Original languageEnglish
Pages (from-to)10873-10878
Number of pages6
JournalJournal of Physical Chemistry B
Volume112
Issue number35
DOIs
Publication statusPublished - 4 Sep 2008

Fingerprint Dive into the research topics of 'Anharmonic behavior in the multisubunit protein apoferritin as revealed by quasi-elastic neutron scattering'. Together they form a unique fingerprint.

Cite this