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Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1996 Oct 1;93(20):10600–10603. doi: 10.1073/pnas.93.20.10600

Initiation sites of protein folding by NMR analysis.

S M Freund 1, K B Wong 1, A R Fersht 1
PMCID: PMC38199  PMID: 8855224

Abstract

Detailed characterization of denatured states of proteins is necessary to understand the interactions that funnel the large number of possible conformations along fast routes for folding. Nuclear magnetic resonance experiments based on the nuclear Overhauser effect (NOE) detect hydrogen atoms close in space and provide information about local structure. Here we present an NMR procedure that detects almost all sequential NOEs between amide hydrogen atoms (HN-HN NOE), including those in random coil regions in a protein, barnase, in urea solutions. A semi-quantitative analysis of these HN-HN NOEs identified partly structured regions that are in remarkable agreement with those found to form early on the reaction pathway. Our results strongly suggest that the folding of barnase initiates at the first helix and the beta-turn between the third and the fourth strands. This strategy of defining residual structure has also worked for cold-denatured barstar and guanidinium hydrochloride-denatured chymotrypsin inhibitor 2 and so should be generally applicable.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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