TY  - JOUR
A1  - Tam, Heng Keat
A1  - Foong, Wuen Ee
A1  - Oswald, Christine
A1  - Herrmann, Andrea
A1  - Zeng, Hui
A1  - Pos, Klaas Martinus
T1  - Allosteric drug transport mechanism of multidrug transporter AcrB
T2  - Nature Communications
N2  - Gram-negative bacteria maintain an intrinsic resistance mechanism against entry of noxious compounds by utilizing highly efficient efflux pumps. The E. coli AcrAB-TolC drug efflux pump contains the inner membrane H+/drug antiporter AcrB comprising three functionally interdependent protomers, cycling consecutively through the loose (L), tight (T) and open (O) state during cooperative catalysis. Here, we present 13 X-ray structures of AcrB in intermediate states of the transport cycle. Structure-based mutational analysis combined with drug susceptibility assays indicate that drugs are guided through dedicated transport channels toward the drug binding pockets. A co-structure obtained in the combined presence of erythromycin, linezolid, oxacillin and fusidic acid shows binding of fusidic acid deeply inside the T protomer transmembrane domain. Thiol cross-link substrate protection assays indicate that this transmembrane domain-binding site can also accommodate oxacillin or novobiocin but not erythromycin or linezolid. AcrB-mediated drug transport is suggested to be allosterically modulated in presence of multiple drugs.
KW  - Antimicrobial resistance
KW  - Bacterial structural biology
KW  - Enzyme mechanisms
KW  - X-ray crystallography
Y1  - 2021
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/63613
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-636134
SN  - 2041-1723
N1  - This work was supported by the German Research Foundation (SFB 807, Transport and Communication across Biological Membranes), the DFG-EXC115 (Cluster of Excellence Frankfurt—Macromolecular Complexes), and the German-Israeli Foundation (Grant No. I-1202-248.9/2012). The research leading to these results was conducted as part of the Translocation consortium (www.translocation.eu) and has received support from the Innovative Medicines Joint Undertaking under Grant Agreement n°115525, resources which are composed of financial contribution from the European Union seventh framework program (FP7/2007-2013). The synchrotron trips to SOLEIL were partly supported by iNEXT, under PID: 7108, funded by the Horizon 2020 programme of the European Union.
Open Access funding enabled and organized by Projekt DEAL.
VL  - 12
IS  - art. 3889
SP  - 1
EP  - 10
PB  - Nature Publishing Group UK
CY  - [London]
ER  -