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Testing water-mediated DNA recognition by the Hin recombinase.

ABSTRACT: The Hin recombinase specifically recognizes its DNA-binding site by means of both major and minor groove interactions. A previous X-ray structure, together with new structures of the Hin DNA-binding domain bound to a recombination half-site that were solved as part of the present study, have revealed that two ordered water molecules are present within the major groove interface. In this report, we test the importance of these waters directly by X-ray crystal structure analysis of complexes with four mutant DNA sequences. These structures, combined with their Hin-binding properties, provide strong support for the critical importance of one of the intermediate waters. A lesser but demonstrable role is ascribed to the second water molecule. The mutant structures also illustrate the prominent roles of thymine methyls both in stabilizing intermediate waters and in interfering with water or amino acid side chain interactions with DNA.

SUBMITTER: Chiu TK

PROVIDER: S-EPMC125850 | biostudies-literature | 2002 Feb

REPOSITORIES: biostudies-literature

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Testing water-mediated DNA recognition by the Hin recombinase.

Chiu Thang Kien TK Sohn Catherine C Dickerson Richard E RE Johnson Reid C RC

The EMBO journal 20020201 4

The Hin recombinase specifically recognizes its DNA-binding site by means of both major and minor groove interactions. A previous X-ray structure, together with new structures of the Hin DNA-binding domain bound to a recombination half-site that were solved as part of the present study, have revealed that two ordered water molecules are present within the major groove interface. In this report, we test the importance of these waters directly by X-ray crystal structure analysis of complexes with ...[more]

PMID: 11847127

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