6IIA

MexB in complex with LMNG

6IIA の概要

• エントリーDOI: 10.2210/pdb6iia/pdb
• 関連するPDBエントリー: 3W9I 3W9J
• 分子名称: Multidrug resistance protein MexB, Lauryl Maltose Neopentyl Glycol (2 entities in total)
• 機能のキーワード: multidrug, transporter, membrane protein
• 由来する生物種: Pseudomonas aeruginosa PAO1
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 684246.42

構造登録者

Nakashima, R.,Sakurai, K.,Nakao, K. (登録日: 2018-10-04, 公開日: 2019-03-27, 最終更新日: 2023-12-13)

主引用文献

Sakurai, K.,Yamasaki, S.,Nakao, K.,Nishino, K.,Yamaguchi, A.,Nakashima, R.
Crystal structures of multidrug efflux pump MexB bound with high-molecular-mass compounds.
Sci Rep, 9:4359-4359, 2019

PubMed Abstract: RND-type multidrug efflux pumps have two voluminous multisite drug-binding pockets named the proximal and distal binding pocket. High- and low-molecular-mass drugs bind to these proximal and distal pocket, respectively. Here, we report the crystal structures of MexB of Pseudomonas aeruginosa bound with high-molecular-mass compounds. Contrary to the expectations, lauryl maltose neopentyl glycol (LMNG, MW 1,005), which is a surfactant larger than the proximal pocket-binding drugs, was found to bind to the distal pocket: one of the two hydrophobic alkyl chains was inserted into the hydrophobic pit, which is the binding site of the efflux pump inhibitor ABI-PP. LMNG is a substrate of the MexAB-OprM system and competitively inhibits the export of other substrates by this system. However, LMNG does not inhibit the export of other substrates by the inhibitor-binding-pit mutant F178W, which retains the export activity of LMNG. The crystal structure of this mutant suggested that the alkyl chain of LMNG could no longer be inserted into the pit because of steric hindrance. We also determined the crystal structure of MexB containing the high-molecular-mass compound neopentyl glycol derivative C7NG (MW 1,028), the binding site of which overlapped with LMNG in the distal pocket, indicating that whether a substrate binds to the distal or proximal pockets is controlled not only by its molecular weight but also by its individual molecular characteristic.

PubMed: 30867446
DOI: 10.1038/s41598-019-40232-2

実験手法

X-RAY DIFFRACTION (2.91 Å)