Structural correspondence between the alpha-helix and the random-flight chain resolves how unfolded proteins can have native-like properties.

Bojan Zagrovic; Vijay S Pande

doi:10.1038/nsb995

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PubMed · 14555998

Structural correspondence between the alpha-helix and the random-flight chain resolves how unfolded proteins can have native-like properties.

Bojan Zagrovic·Vijay S Pande

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Abstract

Recently, we have proposed that, on average, the structure of the unfolded state of small, mostly alpha-helical proteins may be similar to the native structure (the 'mean-structure' hypothesis). After examining thousands of simulations of both the folded and the unfolded states of five polypeptides in atomistic detail at room temperature, we report here a result that seems at odds with the mean-structure hypothesis. Specifically, the average inter-residue distances in the collapsed unfolded structures agree well with the statistics of the ideal random-flight chain with link length of 3.8 A (the length of one amino acid). A possible resolution of this apparent contradiction is offered by the observation that the inter-residue distances in a typical alpha-helix over short stretches are close to the average distances in an ideal random-flight chain.

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Bojan Zagrovic, Vijay S Pande. 2003-10-12. Structural correspondence between the alpha-helix and the random-flight chain resolves how unfolded proteins can have native-like properties.. https://doi.org/10.1038/nsb995

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