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Crystallographic snapshots along a protein-induced DNA-bending pathway.

ABSTRACT: Two new high-resolution cocrystal structures of EcoRV endonuclease bound to DNA show that a large variation in DNA-bending angles is sampled in the ground state binary complex. Together with previous structures, these data reveal a contiguous series of protein conformational states delineating a specific trajectory for the induced-fit pathway. Rotation of the DNA-binding domains, together with movements of two symmetry-related helices binding in the minor groove, causes base unstacking at a key base-pair step and propagates structural changes that assemble the active sites. These structures suggest a complex mechanism for DNA bending that depends on forces generated by interacting protein segments, and on selective neutralization of phosphate charges along the inner face of the bent double helix.

SUBMITTER: Horton NC

PROVIDER: S-EPMC18501 | biostudies-literature | 2000 May

REPOSITORIES: biostudies-literature

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Crystallographic snapshots along a protein-induced DNA-bending pathway.

Horton N C NC Perona J J JJ

Proceedings of the National Academy of Sciences of the United States of America 20000501 11

Two new high-resolution cocrystal structures of EcoRV endonuclease bound to DNA show that a large variation in DNA-bending angles is sampled in the ground state binary complex. Together with previous structures, these data reveal a contiguous series of protein conformational states delineating a specific trajectory for the induced-fit pathway. Rotation of the DNA-binding domains, together with movements of two symmetry-related helices binding in the minor groove, causes base unstacking at a key ...[more]

PMID: 10801972

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