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Folding thermodynamics of a model three-helix-bundle protein.

ABSTRACT: The calculated folding thermodynamics of a simple off-lattice three-helix-bundle protein model under equilibrium conditions shows the experimentally observed protein transitions: a collapse transition, a disordered-to-ordered globule transition, a globule to native-state transition, and the transition from the active native state to a frozen inactive state. The cooperativity and physical origin of the various transitions are explored with a single "optimization" parameter and characterized with the Lindemann criterion for liquid versus solid-state dynamics. Below the folding temperature, the model has a simple free energy surface with a single basin near the native state; the surface is similar to that calculated from a simulation of the same three-helix-bundle protein with an all-atom representation [Boczko, E. M. & Brooks III, C. L. (1995) Science 269, 393-396].

SUBMITTER: Zhou Y

PROVIDER: S-EPMC25010 | biostudies-literature | 1997 Dec

REPOSITORIES: biostudies-literature

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Folding thermodynamics of a model three-helix-bundle protein.

Zhou Y Y Karplus M M

Proceedings of the National Academy of Sciences of the United States of America 19971201 26

The calculated folding thermodynamics of a simple off-lattice three-helix-bundle protein model under equilibrium conditions shows the experimentally observed protein transitions: a collapse transition, a disordered-to-ordered globule transition, a globule to native-state transition, and the transition from the active native state to a frozen inactive state. The cooperativity and physical origin of the various transitions are explored with a single "optimization" parameter and characterized with ...[more]

PMID: 9405629

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