4B3A

Tetracycline repressor class D mutant H100A in complex with tetracycline

4B3A の概要

• エントリーDOI: 10.2210/pdb4b3a/pdb
• 分子名称: TETRACYCLINE REPRESSOR PROTEIN CLASS D, TETRACYCLINE, CHLORIDE ION, ... (5 entities in total)
• 機能のキーワード: transcription, tet-repressor
• 由来する生物種: ESCHERICHIA COLI
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 23796.36

構造登録者

Eltschkner, S.,Schindler, S.,Palm, G.J.,Schneider, J.,Hinrichs, W. (登録日: 2012-07-23, 公開日: 2013-06-12, 最終更新日: 2023-12-20)

主引用文献

Palm, G.J.,Buchholz, I.,Werten, S.,Girbardt, B.,Berndt, L.,Delcea, M.,Hinrichs, W.
Thermodynamics, cooperativity and stability of the tetracycline repressor (TetR) upon tetracycline binding.
Biochim Biophys Acta Proteins Proteom, 1868:140404-140404, 2020

PubMed Abstract: Allosteric regulation of the Tet repressor (TetR) homodimer relies on tetracycline binding that abolishes the affinity for the DNA operator. Previously, interpretation of circular dichroism data called for unfolding of the α-helical DNA-binding domains in absence of binding to DNA or tetracycline. Our small angle X-ray scattering of TetR(D) in solution contradicts this unfolding as a physiological process. Instead, in the core domain crystal structures analyses show increased immobilisation of helix α9 and two C-terminal turns of helix α8 upon tetracycline binding. Tetracycline complexes of TetR(D) and four single-site alanine variants were characterised by isothermal titration calorimetry, fluorescence titration, X-ray crystal structures, and melting curves. Five crystal structures confirm that Thr103 is a key residue for the allosteric events of induction, with the T103A variant lacking induction by any tetracycline. The T103A variant shows anti-cooperative inducer binding, and a melting curve of the tetracycline complex different to TetR(D) and other variants. For the N82A variant inducer binding is clearly anti-cooperative but triggers the induced conformation.

PubMed: 32114262
DOI: 10.1016/j.bbapap.2020.140404

実験手法

X-RAY DIFFRACTION (1.7 Å)