1BIX

THE CRYSTAL STRUCTURE OF THE HUMAN DNA REPAIR ENDONUCLEASE HAP1 SUGGESTS THE RECOGNITION OF EXTRA-HELICAL DEOXYRIBOSE AT DNA ABASIC SITES

Summary for 1BIX

• Entry DOI: 10.2210/pdb1bix/pdb
• Descriptor: AP ENDONUCLEASE 1, SAMARIUM (III) ION, PLATINUM (II) ION, ... (4 entities in total)
• Functional Keywords: dna repair, endonuclease, hap1, ref-1, abasic site recognition
• Biological source: Homo sapiens (human)
• Cellular location: Nucleus. DNA-(apurinic or apyrimidinic site) lyase, mitochondrial: Mitochondrion: P27695
• Total number of polymer chains: 1
• Total formula weight: 33084.20

Authors

Gorman, M.A.,Morera, S.,Rothwell, D.G.,De La Fortelle, E.,Mol, C.D.,Tainer, J.A.,Hickson, I.D.,Freemont, P.S. (deposition date: 1998-06-19, release date: 1999-06-22, Last modification date: 2024-02-07)

Primary citation

Gorman, M.A.,Morera, S.,Rothwell, D.G.,de La Fortelle, E.,Mol, C.D.,Tainer, J.A.,Hickson, I.D.,Freemont, P.S.
The crystal structure of the human DNA repair endonuclease HAP1 suggests the recognition of extra-helical deoxyribose at DNA abasic sites.
EMBO J., 16:6548-6558, 1997

PubMed Abstract: The structure of the major human apurinic/ apyrimidinic endonuclease (HAP1) has been solved at 2.2 A resolution. The enzyme consists of two symmetrically related domains of similar topology and has significant structural similarity to both bovine DNase I and its Escherichia coli homologue exonuclease III (EXOIII). A structural comparison of these enzymes reveals three loop regions specific to HAP1 and EXOIII. These loop regions apparently act in DNA abasic site (AP) recognition and cleavage since DNase I, which lacks these loops, correspondingly lacks AP site specificity. The HAP1 structure furthermore suggests a mechanism for AP site binding which involves the recognition of the deoxyribose moiety in an extrahelical conformation, rather than a 'flipped-out' base opposite the AP site.

PubMed: 9351835
DOI: 10.1093/emboj/16.21.6548

Experimental method

X-RAY DIFFRACTION (2.2 Å)