Dataset Information

Hysteresis as a Marker for Complex, Overlapping Landscapes in Proteins.

ABSTRACT: Topologically complex proteins fold by multiple routes as a result of hard-to-fold regions of the proteins. Oftentimes these regions are introduced into the protein scaffold for function and increase frustration in the otherwise smooth-funneled landscape. Interestingly, while functional regions add complexity to folding landscapes, they may also contribute to a unique behavior referred to as hysteresis. While hysteresis is predicted to be rare, it is observed in various proteins, including proteins containing a unique peptide cyclization to form a fluorescent chromophore as well as proteins containing a knotted topology in their native fold. Here, hysteresis is demonstrated to be a consequence of the decoupling of unfolding events from the isomerization or hula-twist of a chromophore in one protein and the untying of the knot in a second protein system. The question now is- can hysteresis be a marker for the interplay of landscapes where complex folding and functional regions overlap?

SUBMITTER: Andrews BT

PROVIDER: S-EPMC3601837 | biostudies-literature | 2013 Jan

REPOSITORIES: biostudies-literature

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Hysteresis as a Marker for Complex, Overlapping Landscapes in Proteins.

Andrews Benjamin T BT Capraro Dominique T DT Sulkowska Joanna I JI Onuchic José N JN Jennings Patricia A PA

The journal of physical chemistry letters 20121218 1

Topologically complex proteins fold by multiple routes as a result of hard-to-fold regions of the proteins. Oftentimes these regions are introduced into the protein scaffold for function and increase frustration in the otherwise smooth-funneled landscape. Interestingly, while functional regions add complexity to folding landscapes, they may also contribute to a unique behavior referred to as hysteresis. While hysteresis is predicted to be rare, it is observed in various proteins, including prote ...[more]

PMID: 23525263

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Dataset Information

Hysteresis as a Marker for Complex, Overlapping Landscapes in Proteins.

Publications

Hysteresis as a Marker for Complex, Overlapping Landscapes in Proteins.

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