Telling, Mark, Neylon, Cameron, Kilcoyne, Susan H. and Arrighi, Valeria (2008) Anharmonic Behavior in the Multisubunit Protein Apoferritin as Revealed by Quasi-Elastic Neutron Scattering. Journal of Physical Chemistry B, 112 (35). pp. 10873-10878. ISSN 1089-5647
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, σ
) 5.0 kJ · mol-1). Our results are likened to those reported for other proteins.

Information
Library
Documents
[thumbnail of apo_QENS.pdf]
apo_QENS.pdf - Published Version
Restricted to Registered users only

Download (724kB)
Statistics

View Item (login required)
View Item (login required)
Add to AnyAdd to TwitterAdd to FacebookAdd to LinkedinAdd to PinterestAdd to Email