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Coherent neutron scattering and collective dynamics in the protein, GFP.

ABSTRACT: Collective dynamics are considered to be one of the major properties of soft materials, including biological macromolecules. We present coherent neutron scattering studies of the low-frequency vibrations, the so-called boson peak, in fully deuterated green fluorescent protein (GFP). Our analysis revealed unexpectedly low coherence of the atomic motions in GFP. This result implies a low amount of in-phase collective motion of the secondary structural units contributing to the boson peak vibrations and fast conformational fluctuations on the picosecond timescale. These observations are in contrast to earlier studies of polymers and glass-forming systems, and suggest that random or out-of-phase motions of the ?-strands contribute greater than two-thirds of the intensity to the low-frequency vibrational spectra of GFP.

SUBMITTER: Nickels JD

PROVIDER: S-EPMC3824694 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature

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Coherent neutron scattering and collective dynamics in the protein, GFP.

Nickels Jonathan D JD Perticaroli Stefania S O'Neill Hugh H Zhang Qiu Q Ehlers Georg G Sokolov Alexei P AP

Biophysical journal 20131101 9

Collective dynamics are considered to be one of the major properties of soft materials, including biological macromolecules. We present coherent neutron scattering studies of the low-frequency vibrations, the so-called boson peak, in fully deuterated green fluorescent protein (GFP). Our analysis revealed unexpectedly low coherence of the atomic motions in GFP. This result implies a low amount of in-phase collective motion of the secondary structural units contributing to the boson peak vibration ...[more]

PMID: 24209864

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