8RF1

BmrA E504-R6G

8RF1 の概要

• エントリーDOI: 10.2210/pdb8rf1/pdb
• EMDBエントリー: 19115
• 分子名称: Multidrug resistance ABC transporter ATP-binding/permease protein BmrA, RHODAMINE 6G (2 entities in total)
• 機能のキーワード: bmra, multidrug transporter, drug resistance, abc transporter, transport protein
• 由来する生物種: Bacillus subtilis
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 132381.40

構造登録者

Gobet, A.,Zarkadas, E.,Schoehn, G.,Falson, P.,Chaptal, V. (登録日: 2023-12-12, 公開日: 2025-01-01, 最終更新日: 2025-07-16)

主引用文献

Gobet, A.,Moissonnier, L.,Zarkadas, E.,Magnard, S.,Bettler, E.,Martin, J.,Terreux, R.,Schoehn, G.,Orelle, C.,Jault, J.M.,Falson, P.,Chaptal, V.
Rhodamine6G and Hœchst33342 narrow BmrA conformational spectrum for a more efficient use of ATP.
Nat Commun, 16:1745-1745, 2025

PubMed Abstract: Multidrug ABC transporters harness the energy of ATP binding and hydrolysis to translocate substrates out of the cell and detoxify them. While this involves a well-accepted alternating access mechanism, molecular details of this interplay are still elusive. Rhodamine6G binding on a catalytic inactive mutant of the homodimeric multidrug ABC transporter BmrA triggers a cooperative binding of ATP on the two identical nucleotide-binding-sites, otherwise michaelian. Here, we investigate this asymmetric behavior via a structural-enzymology approach, solving cryoEM structures of BmrA at defined ATP ratios, highlighting the plasticity of BmrA as it undergoes the transition from inward to outward facing conformations. Analysis of continuous heterogeneity within cryoEM data and structural dynamics, reveals that Rhodamine6G narrows the conformational spectrum explored by the nucleotide-binding domains. We observe the same behavior for the other drug Hœchst33342. Following on these findings, the effect of drug-binding showed an ATPase stimulation and a maximal transport activity of the wild-type protein at the concentration-range where the cooperative transition occurs. Altogether, these findings provide a description of the influence of drug binding on the ATP-binding sites through a change in conformational dynamics.

PubMed: 39966360
DOI: 10.1038/s41467-025-56849-z

実験手法

ELECTRON MICROSCOPY (4.3 Å)