1ZM7

Crystal structure of D. melanogaster deoxyribonucleoside kinase mutant N64D in complex with dTTP

1ZM7 の概要

• エントリーDOI: 10.2210/pdb1zm7/pdb
• 関連するPDBエントリー: 1OT3 1Oe0 1j90 1zmx
• 分子名称: Deoxynucleoside kinase, THYMIDINE-5'-TRIPHOSPHATE, MAGNESIUM ION, ... (4 entities in total)
• 機能のキーワード: drosohila melanogaster, dnk, n64d, mutant, transferase
• 由来する生物種: Drosophila melanogaster (fruit fly)
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 109583.74

構造登録者

Welin, M.,Skovgaard, T.,Knecht, W.,Berenstein, D.,Munch-Petersen, B.,Piskur, J.,Eklund, H. (登録日: 2005-05-10, 公開日: 2005-05-17, 最終更新日: 2023-08-23)

主引用文献

Welin, M.,Skovgaard, T.,Knecht, W.,Zhu, C.,Berenstein, D.,Munch-Petersen, B.,Piskur, J.,Eklund, H.
Structural basis for the changed substrate specificity of Drosophila melanogaster deoxyribonucleoside kinase mutant N64D.
Febs J., 272:3733-3742, 2005

PubMed Abstract: The Drosophila melanogaster deoxyribonucleoside kinase (Dm-dNK) double mutant N45D/N64D was identified during a previous directed evolution study. This mutant enzyme had a decreased activity towards the natural substrates and decreased feedback inhibition with dTTP, whereas the activity with 3'-modified nucleoside analogs like 3'-azidothymidine (AZT) was nearly unchanged. Here, we identify the mutation N64D as being responsible for these changes. Furthermore, we crystallized the mutant enzyme in the presence of one of its substrates, thymidine, and the feedback inhibitor, dTTP. The introduction of the charged Asp residue appears to destabilize the LID region (residues 167-176) of the enzyme by electrostatic repulsion and no hydrogen bond to the 3'-OH is made in the substrate complex by Glu172 of the LID region. This provides a binding space for more bulky 3'-substituents like the azido group in AZT but influences negatively the interactions between Dm-dNK, substrates and feedback inhibitors based on deoxyribose. The detailed picture of the structure-function relationship provides an improved background for future development of novel mutant suicide genes for Dm-dNK-mediated gene therapy.

PubMed: 16008571
DOI: 10.1111/j.1742-4658.2005.04803.x

実験手法

X-RAY DIFFRACTION (2.2 Å)