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Trimeric domain-swapped barnase.

ABSTRACT: The structure of a trimeric domain-swapped form of barnase (EC 3.1. 27.3) was determined by x-ray crystallography at a resolution of 2.2 A from crystals of space group R32. Residues 1-36 of one molecule associate with residues 41-110 from another molecule related through threefold symmetry. The resulting cyclic trimer contains three protein folds that are very similar to those in monomeric barnase. Both swapped domains contain a nucleation site for folding. The formation of a domain-swapped trimer is consistent with the description of the folding process of monomeric barnase as the formation and subsequent association of two foldons.

SUBMITTER: Zegers I

PROVIDER: S-EPMC15308 | biostudies-literature | 1999 Feb

REPOSITORIES: biostudies-literature

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Trimeric domain-swapped barnase.

Zegers I I Deswarte J J Wyns L L

Proceedings of the National Academy of Sciences of the United States of America 19990201 3

The structure of a trimeric domain-swapped form of barnase (EC 3.1. 27.3) was determined by x-ray crystallography at a resolution of 2.2 A from crystals of space group R32. Residues 1-36 of one molecule associate with residues 41-110 from another molecule related through threefold symmetry. The resulting cyclic trimer contains three protein folds that are very similar to those in monomeric barnase. Both swapped domains contain a nucleation site for folding. The formation of a domain-swapped trim ...[more]

PMID: 9927651

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