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Crystal structure of the Escherichia coli dcm very-short-patch DNA repair endonuclease bound to its reaction product-site in a DNA superhelix.

ABSTRACT: Very-short-patch repair (Vsr) enzymes occur in a variety of bacteria, where they initiate nucleotide excision repair of G:T mismatches arising by deamination of 5-methyl-cytosines in specific regulatory sequences. We have now determined the structure of the archetypal dcm-Vsr endonuclease from Escherichia coli bound to the cleaved authentic hemi-deaminated/hemi-methylated dcm sequence 5'-C-OH-3' 5'-p-T-p-A-p-G-p-G-3'/3'-G-p-G-p-T-p(Me5)C-p-C formed by self-assembly of a 12mer oligonucleotide into a continuous nicked DNA superhelix. The structure reveals the presence of a Hoogsteen base pair within the deaminated recognition sequence and the substantial distortions of the DNA that accompany Vsr binding to product sites.

SUBMITTER: Bunting KA

PROVIDER: S-EPMC152875 | biostudies-literature | 2003 Mar

REPOSITORIES: biostudies-literature

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Crystal structure of the Escherichia coli dcm very-short-patch DNA repair endonuclease bound to its reaction product-site in a DNA superhelix.

Bunting Karen A KA Roe S Mark SM Headley Anthony A Brown Tom T Savva Renos R Pearl Laurence H LH

Nucleic acids research 20030301 6

Very-short-patch repair (Vsr) enzymes occur in a variety of bacteria, where they initiate nucleotide excision repair of G:T mismatches arising by deamination of 5-methyl-cytosines in specific regulatory sequences. We have now determined the structure of the archetypal dcm-Vsr endonuclease from Escherichia coli bound to the cleaved authentic hemi-deaminated/hemi-methylated dcm sequence 5'-C-OH-3' 5'-p-T-p-A-p-G-p-G-3'/3'-G-p-G-p-T-p(Me5)C-p-C formed by self-assembly of a 12mer oligonucleotide int ...[more]

PMID: 12626704

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