5HML

Crystal Structure of T5 D15 Protein Co-crystallized with Metal Ions

5HML の概要

• エントリーDOI: 10.2210/pdb5hml/pdb
• 分子名称: Exodeoxyribonuclease, MAGNESIUM ION, CHLORIDE ION, ... (7 entities in total)
• 機能のキーワード: metal ion complex, flap endonuclease, alternative conformations, hydrolase
• 由来する生物種: Escherichia phage T5
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 63709.58

構造登録者

Flemming, C.S.,Feng, M.,Sedelnikova, S.E.,Zhang, J.,Rafferty, J.B.,Sayers, J.R.,Artymiuk, P.J. (登録日: 2016-01-16, 公開日: 2016-06-01, 最終更新日: 2024-01-10)

主引用文献

AlMalki, F.A.,Flemming, C.S.,Zhang, J.,Feng, M.,Sedelnikova, S.E.,Ceska, T.,Rafferty, J.B.,Sayers, J.R.,Artymiuk, P.J.
Direct observation of DNA threading in flap endonuclease complexes.
Nat.Struct.Mol.Biol., 23:640-646, 2016

PubMed Abstract: Maintenance of genome integrity requires that branched nucleic acid molecules be accurately processed to produce double-helical DNA. Flap endonucleases are essential enzymes that trim such branched molecules generated by Okazaki-fragment synthesis during replication. Here, we report crystal structures of bacteriophage T5 flap endonuclease in complexes with intact DNA substrates and products, at resolutions of 1.9-2.2 Å. They reveal single-stranded DNA threading through a hole in the enzyme, which is enclosed by an inverted V-shaped helical arch straddling the active site. Residues lining the hole induce an unusual barb-like conformation in the DNA substrate, thereby juxtaposing the scissile phosphate and essential catalytic metal ions. A series of complexes and biochemical analyses show how the substrate's single-stranded branch approaches, threads through and finally emerges on the far side of the enzyme. Our studies suggest that substrate recognition involves an unusual 'fly-casting, thread, bend and barb' mechanism.

PubMed: 27273516
DOI: 10.1038/nsmb.3241

実験手法

X-RAY DIFFRACTION (1.482 Å)