1JT0

Crystal structure of a cooperative QacR-DNA complex

1JT0 の概要

• エントリーDOI: 10.2210/pdb1jt0/pdb
• 関連するPDBエントリー: 1JT6 1JTY 1JUM 1JUP 1JUS
• 分子名称: QACA operator, HYPOTHETICAL TRANSCRIPTIONAL REGULATOR IN QACA 5'REGION, SULFATE ION, ... (4 entities in total)
• 機能のキーワード: multidrug binding protein, cooperative dna binding, dimer of dimers, transcription-dna complex, transcription/dna
• 由来する生物種: Staphylococcus aureus
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 109621.54

構造登録者

Schumacher, M.A.,Miller, M.C.,Grkovic, S.,Brown, M.H.,Skurray, R.A.,Brennan, R.G. (登録日: 2001-08-20, 公開日: 2002-03-08, 最終更新日: 2024-02-07)

主引用文献

Schumacher, M.A.,Miller, M.C.,Grkovic, S.,Brown, M.H.,Skurray, R.A.,Brennan, R.G.
Structural basis for cooperative DNA binding by two dimers of the multidrug-binding protein QacR.
EMBO J., 21:1210-1218, 2002

PubMed Abstract: The Staphylococcus aureus multidrug-binding protein QacR represses transcription of the qacA multidrug transporter gene and is induced by multiple structurally dissimilar drugs. QacR is a member of the TetR/CamR family of transcriptional regulators, which share highly homologous N-terminal DNA-binding domains connected to seemingly non-homologous ligand-binding domains. Unlike other TetR members, which bind approximately 15 bp operators, QacR recognizes an unusually long 28 bp operator, IR1, which it appears to bind cooperatively. To elucidate the DNA-binding mechanism of QacR, we determined the 2.90 A resolution crystal structure of a QacR-IR1 complex. Strikingly, our data reveal that the DNA recognition mode of QacR is distinct from TetR and involves the binding of a pair of QacR dimers. In this unique binding mode, recognition at each IR1 half-site is mediated by a complement of DNA contacts made by two helix-turn-helix motifs. The inferred cooperativity does not arise from cross-dimer protein-protein contacts, but from the global undertwisting and major groove widening elicited by the binding of two QacR dimers.

PubMed: 11867549
DOI: 10.1093/emboj/21.5.1210

実験手法

X-RAY DIFFRACTION (2.9 Å)