6UKE

HhaI endonuclease in Complex with Iodine-Labelled DNA

6UKE の概要

• エントリーDOI: 10.2210/pdb6uke/pdb
• 分子名称: HhaI Restriction Endonuclease, DNA (5'-D(*TP*CP*CP*AP*AP*GP*CP*GP*CP*AP*AP*CP*G)-3'), DNA (5'-D(*CP*GP*(5IT)P*TP*GP*CP*GP*CP*TP*(5IT)P*GP*GP*A)-3'), ... (8 entities in total)
• 機能のキーワード: restriction, modification, protein-dna complex, iodine phasing, hydrolase-dna complex, hydrolase/dna
• 由来する生物種: Haemophilus parahaemolyticus; 詳細
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 39577.41

構造登録者

Horton, J.R.,Cheng, X. (登録日: 2019-10-04, 公開日: 2019-12-18, 最終更新日: 2024-03-13)

主引用文献

Horton, J.R.,Yang, J.,Zhang, X.,Petronzio, T.,Fomenkov, A.,Wilson, G.G.,Roberts, R.J.,Cheng, X.
Structure of HhaI endonuclease with cognate DNA at an atomic resolution of 1.0 angstrom.
Nucleic Acids Res., 48:1466-1478, 2020

PubMed Abstract: HhaI, a Type II restriction endonuclease, recognizes the symmetric sequence 5'-GCG↓C-3' in duplex DNA and cleaves ('↓') to produce fragments with 2-base, 3'-overhangs. We determined the structure of HhaI in complex with cognate DNA at an ultra-high atomic resolution of 1.0 Å. Most restriction enzymes act as dimers with two catalytic sites, and cleave the two strands of duplex DNA simultaneously, in a single binding event. HhaI, in contrast, acts as a monomer with only one catalytic site, and cleaves the DNA strands sequentially, one after the other. HhaI comprises three domains, each consisting of a mixed five-stranded β sheet with a defined function. The first domain contains the catalytic-site; the second contains residues for sequence recognition; and the third contributes to non-specific DNA binding. The active-site belongs to the 'PD-D/EXK' superfamily of nucleases and contains the motif SD-X11-EAK. The first two domains are similar in structure to two other monomeric restriction enzymes, HinP1I (G↓CGC) and MspI (C↓CGG), which produce fragments with 5'-overhangs. The third domain, present only in HhaI, shifts the positions of the recognition residues relative to the catalytic site enabling this enzyme to cleave the recognition sequence at a different position. The structure of M.HhaI, the biological methyltransferase partner of HhaI, was determined earlier. Together, these two structures represent the first natural pair of restriction-modification enzymes to be characterized in atomic detail.

PubMed: 31879785
DOI: 10.1093/nar/gkz1195

実験手法

X-RAY DIFFRACTION (1.62 Å)