Alternate pathways for folding in the flavodoxin fold family revealed by a nucleation-growth model.

Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, 6001 Forest Park Blvd., Room ND10.124, Dallas, TX 75235-9050, USA.
Journal of Molecular Biology (Impact Factor: 3.91). 06/2006; 358(3):646-53. DOI: 10.1016/j.jmb.2006.02.026
Source: PubMed

ABSTRACT A recent study of experimental results for flavodoxin-like folds suggests that proteins from this family may exhibit a similar, signature pattern of folding intermediates. We study the folding landscapes of three proteins from the flavodoxin family (CheY, apoflavodoxin, and cutinase) using a simple nucleation and growth model that accurately describes both experimental and simulation results for the transition state structure, and the structure of on-pathway and misfolded intermediates for CheY. Although the landscape features of these proteins agree in basic ways with the results of the study, the simulations exhibit a range of folding behaviours consistent with two alternate folding routes corresponding to nucleation and growth from either side of the central beta-strand.

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