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UV damage endonuclease employs a novel dual-dinucleotide flipping mechanism to recognize different DNA lesions.

ABSTRACT: Repairing damaged DNA is essential for an organism's survival. UV damage endonuclease (UVDE) is a DNA-repair enzyme that can recognize and incise different types of damaged DNA. We present the structure of Sulfolobus acidocaldarius UVDE on its own and in a pre-catalytic complex with UV-damaged DNA containing a 6-4 photoproduct showing a novel 'dual dinucleotide flip' mechanism for recognition of damaged dipyrimidines: the two purines opposite to the damaged pyrimidine bases are flipped into a dipurine-specific pocket, while the damaged bases are also flipped into another cleft.

SUBMITTER: Meulenbroek EM

PROVIDER: S-EPMC3553973 | biostudies-literature | 2013 Jan

REPOSITORIES: biostudies-literature

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UV damage endonuclease employs a novel dual-dinucleotide flipping mechanism to recognize different DNA lesions.

Meulenbroek Elisabeth M EM Peron Cane Caroline C Jala Isabelle I Iwai Shigenori S Moolenaar Geri F GF Goosen Nora N Pannu Navraj S NS

Nucleic acids research 20121204 2

Repairing damaged DNA is essential for an organism's survival. UV damage endonuclease (UVDE) is a DNA-repair enzyme that can recognize and incise different types of damaged DNA. We present the structure of Sulfolobus acidocaldarius UVDE on its own and in a pre-catalytic complex with UV-damaged DNA containing a 6-4 photoproduct showing a novel 'dual dinucleotide flip' mechanism for recognition of damaged dipyrimidines: the two purines opposite to the damaged pyrimidine bases are flipped into a di ...[more]

PMID: 23221644

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