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Crystal Structure of endonuclease IV from Geobacillus kaustophilusCrystal Structure of endonuclease IV from Geobacillus kaustophilus
Structural highlights
FunctionEND4_GEOKA Endonuclease IV plays a role in DNA repair. It cleaves phosphodiester bonds at apurinic or apyrimidinic sites (AP sites) to produce new 5'-ends that are base-free deoxyribose 5-phosphate residues. It preferentially attacks modified AP sites created by bleomycin and neocarzinostatin. Publication Abstract from PubMedEndonuclease IV (EndoIV) is an endonuclease that acts at apurinic/apyrimidinic (AP) sites and is classified as either long-type or short-type. The crystal structures of representative types of EndoIV from Geobacillus kaustophilus and Thermus thermophilus HB8 were determined using X-ray crystallography. G. kaustophilus EndoIV (the long type) had a higher affinity for double-stranded DNA containing an AP-site analogue than T. thermophilus EndoIV (the short type). Structural analysis of the two different EndoIVs suggested that a C-terminal DNA-recognition loop that is only present in the long type contributes to its high affinity for AP sites. A mutation analysis showed that Lys267 in the C-terminal DNA-recognition loop plays an important role in DNA binding. An additional C-terminal loop in endonuclease IV, an apurinic/apyrimidinic endonuclease, controls binding affinity to DNA.,Asano R, Ishikawa H, Nakane S, Nakagawa N, Kuramitsu S, Masui R Acta Crystallogr D Biol Crystallogr. 2011 Mar;67(Pt 3):149-55. Epub 2011, Feb 15. PMID:21358045[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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