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Comparative Dynamics of Methionine Side-Chain in FMOC-Methionine and in Amyloid Fibrils.

ABSTRACT: We compared the dynamics of key methionine methyl groups in the water-accessible hydrophobic cavity of amyloid fibrils and Fluorenylmethyloxycarbonyl-Methionine (FMOC-Met), which renders general hydrophobicity to the environment without the complexity of the protein. Met35 in the hydrated cavity was recently found to undergo a dynamical cross-over from the dominance of methyl rotations at low temperatures to the dominance of diffusive motion of methyl axis at high temperatures. Current results indicate that in FMOC-Met this cross-over is suppressed, similar to what was observed for the dry fibrils, indicating that hydration of the cavity is driving the onset of the dynamical transition.

SUBMITTER: Vugmeyster L

PROVIDER: S-EPMC5612497 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Comparative Dynamics of Methionine Side-Chain in FMOC-Methionine and in Amyloid Fibrils.

Vugmeyster Liliya L Ostrovsky Dmitry D

Chemical physics letters 20170214

We compared the dynamics of key methionine methyl groups in the water-accessible hydrophobic cavity of amyloid fibrils and Fluorenylmethyloxycarbonyl-Methionine (FMOC-Met), which renders general hydrophobicity to the environment without the complexity of the protein. Met35 in the hydrated cavity was recently found to undergo a dynamical cross-over from the dominance of methyl rotations at low temperatures to the dominance of diffusive motion of methyl axis at high temperatures. Current results i ...[more]

PMID: 28959059

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