6K0W

DNA methyltransferase in complex with sinefungin

6K0W の概要

• エントリーDOI: 10.2210/pdb6k0w/pdb
• 分子名称: Adenine specific DNA methyltransferase (Mod), SINEFUNGIN (3 entities in total)
• 機能のキーワード: dna methyltransferase, sinefungin, dna binding protein
• 由来する生物種: Helicobacter pylori 26695
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 284004.61

構造登録者

Narayanan, N.,Nair, D.T. (登録日: 2019-05-07, 公開日: 2019-12-11, 最終更新日: 2024-03-27)

主引用文献

Narayanan, N.,Banerjee, A.,Jain, D.,Kulkarni, D.S.,Sharma, R.,Nirwal, S.,Rao, D.N.,Nair, D.T.
Tetramerization at Low pH Licenses DNA Methylation Activity of M.HpyAXI in the Presence of Acid Stress.
J.Mol.Biol., 432:324-342, 2020

PubMed Abstract: Methylation of genomic DNA can influence the transcription profile of an organism and may generate phenotypic diversity for rapid adaptation in a dynamic environment. M.HpyAXI is a Type III DNA methyltransferase present in Helicobacter pylori and is upregulated at low pH. This enzyme may alter the expression of critical genes to ensure the survival of this pathogen at low pH inside the human stomach. M.HpyAXI methylates the adenine in the target sequence (5'-GCAG-3') and shows maximal activity at pH 5.5. Type III DNA methyltransferases are found to form an inverted dimer in the functional form. We observe that M.HpyAXI forms a nonfunctional dimer at pH 8.0 that is incapable of DNA binding and methylation activity. However, at pH 5.5, two such dimers associate to form a tetramer that now includes two functional dimers that can bind and methylate the target DNA sequence. Overall, we observe that the pH-dependent tetramerization of M.HpyAXI ensures that the enzyme is licensed to act only in the presence of acid stress.

PubMed: 31628946
DOI: 10.1016/j.jmb.2019.10.001

実験手法

X-RAY DIFFRACTION (2.65 Å)