4RLB

Crystal structure of Acinetobacter baumannii CarO2

4RLB の概要

• エントリーDOI: 10.2210/pdb4rlb/pdb
• 関連するPDBエントリー: 4FUV 4RL9 4RLC
• 分子名称: Carbapenem-associated resistance protein (1 entity in total)
• 機能のキーワード: outer membrane protein, beta-barrel, membrane protein
• 由来する生物種: Acinetobacter baumannii
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 55238.73

構造登録者

Zahn, M.,Basle, A.,van den Berg, B. (登録日: 2014-10-16, 公開日: 2015-04-22, 最終更新日: 2024-02-28)

主引用文献

Zahn, M.,D'Agostino, T.,Eren, E.,Basle, A.,Ceccarelli, M.,van den Berg, B.
Small-Molecule Transport by CarO, an Abundant Eight-Stranded beta-Barrel Outer Membrane Protein from Acinetobacter baumannii.
J.Mol.Biol., 427:2329-2339, 2015

PubMed Abstract: Outer membrane (OM) β-barrel proteins composed of 12-18 β-strands mediate cellular entry of small molecules in Gram-negative bacteria. Small OM proteins with barrels of 10 strands or less are not known to transport small molecules. CarO (carbapenem-associated outer membrane protein) from Acinetobacter baumannii is a small OM protein that has been implicated in the uptake of ornithine and carbapenem antibiotics. Here we report crystal structures of three isoforms of CarO. The structures are very similar and show a monomeric eight-stranded barrel lacking an open channel. CarO has a substantial extracellular domain resembling a glove that contains all the divergent residues between the different isoforms. Liposome swelling experiments demonstrate that full-length CarO and a "loop-less" truncation mutant mediate small-molecule uptake at low levels but that they are unlikely to mediate passage of carbapenem antibiotics. These results are confirmed by biased molecular dynamics simulations that allowed us to quantitatively model the transport of selected small molecules.

PubMed: 25846137
DOI: 10.1016/j.jmb.2015.03.016

実験手法

X-RAY DIFFRACTION (2.7 Å)