The membrane-proximal domain of the periplasmic adapter protein plays a role in vetting substrates utilising channels 1 and 2 of RND efflux transporters
The membrane-proximal domain of the periplasmic adapter protein plays a role in vetting substrates utilising channels 1 and 2 of RND efflux transporters
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周质接头蛋白的近膜结构域在利用 RND 外排转运蛋白的通道 1 和 2 审查底物中发挥作用
DOI：
10.1101/2021.10.05.463233
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Alav I
中科院分区：
文献类型：
--
作者：
Alav I
耐药-结节分裂（RND）外排泵的主动外排是临床相关革兰氏阴性菌抗生素耐药的主要因素。三联RND泵，如鼠伤寒沙门菌的AcrAB-TolC，由一个内膜RND转运蛋白、一个质周适应蛋白（PAP）和一个外膜因子组成。先前，我们阐明了PAP AcrA中的结合位点（称为结合盒），这些结合位点对acrb转运体识别很重要。在这里，我们通过识别PAP- rnd结合中最关键的残基来改进结合盒模型，并表明在密切相关的PAP AcrE中相应的rnd结合残基对AcrB相互作用也很重要。此外，我们的分析确定了AcrA （K366）中的膜近端结构域（MPD）残基，当突变时，利用不同的AcrB外排通道（即通道1和2）对底物的运输产生不同的影响，这支持了PAP在感知转运体近端结合袋（PBP）的底物占据状态和底物审查中的潜在作用。我们的模型预测PAP的MPD和RND转运体之间在利用PBP的底物的生产性出口中存在密切的相互作用。抗生素耐药性极大地威胁着我们治疗传染病的能力。在革兰氏阴性菌中，AcrAB-TolC等三方外排泵的过度表达有助于产生多药耐药，因为它们输出许多不同种类的抗生素。AcrAB-TolC泵由三个组成部分组成：质周适配器蛋白（PAP） AcrA， rnd转运蛋白AcrB和外膜因子TolC。在这里，我们鉴定了AcrA的关键残基，这些残基对AcrA在肠炎沙门氏菌鼠伤寒沙门氏菌中的功能至关重要。此外，我们发现AcrA与AcrE（一个密切相关的PAP）共享这些关键残基，这解释了它们与AcrB的互操作性。重要的是，我们在AcrA的膜近端区域发现了一个残基，当突变时，该残基影响不同底物如何访问AcrB并影响下游外排AcrA通道。了解pap在三方RND泵的组装和功能中所起的作用，可以指导新的方法来抑制其对抗抗生素耐药性的功能。
Active efflux by resistance-nodulation-division (RND) efflux pumps is a major contributor to antibiotic resistance in clinically relevant Gram-negative bacteria. Tripartite RND pumps, such as AcrAB-TolC ofSalmonella entericaserovar Typhimurium, comprise of an inner membrane RND transporter, a periplasmic adaptor protein (PAP) and an outer membrane factor. Previously, we elucidated binding sites within the PAP AcrA (termed binding boxes) that were important for AcrB-transporter recognition. Here, we have refined the binding box model by identifying the most critical residues involved in PAP-RND binding and show that the corresponding RND-binding residues in the closely related PAP AcrE are also important for AcrB interactions. In addition, our analysis identified a membrane-proximal domain (MPD)-residue in AcrA (K366), that when mutated, differentially affects transport of substrates utilising different AcrB efflux-channels, namely channels 1 and 2, supporting a potential role for the PAP in sensing the substrate-occupied state of the proximal binding pocket (PBP) of the transporter and substrate vetting. Our model predicts that there is a close interplay between the MPD of the PAP and the RND transporter in the productive export of substrates utilising the PBP.ImportanceAntibiotic resistance greatly threatens our ability to treat infectious diseases. In Gram-negative bacteria, overexpression of tripartite efflux pumps, such as AcrAB-TolC, contributes to multidrug resistance because they export many different classes of antibiotics. The AcrAB-TolC pump is made up of three components: the periplasmic adaptor protein (PAP) AcrA, the RND-transporter AcrB, and the outer-membrane factor TolC. Here, we identified critical residues of AcrA that are important for its function with AcrB inSalmonella entericaserovar Typhimurium. Also, we show that AcrA shares these critical residues with AcrE, a closely related PAP, explaining their interoperability with AcrB. Importantly, we identified a residue in the membrane-proximal domain of AcrA that when mutated affected how different substrates access AcrB and impacted downstream effluxviaTolC channel. Understanding the role that PAPs play in the assembly and function of tripartite RND pumps can guide novel ways to inhibit their function to combat antibiotic resistance.
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DOI：
10.3390/antibiotics10070774
发表时间：
2021-06-25
期刊：
Antibiotics (Basel, Switzerland)
影响因子：
--
作者：
Zwama M;Nishino K
通讯作者：
Nishino K
影响因子：
3.6
作者：
Nishino, K;Latifi, T;Groisman, EA
通讯作者：
Groisman, EA
极端酸调节大肠杆菌 K-12 中多药外排泵 MdtEF-TolC 和 AcrAB-TolC 的适应性权衡
影响因子：
4.4
作者：
Samantha H. Schaffner;Abigail V. Lee;M. Pham;Beimnet B. Kassaye;Haofan Li;Sheetal Tallada;Cassandra Lis;Mark Lang;Yangyang Liu;Nafeez Ahmed;Logan G. Galbraith;Jeremy Moore;Katarina M. Bischof;Chelsea C. Menke;J. Slonczewski
通讯作者：
J. Slonczewski
影响因子：
5.7
作者：
Mikolosko, J;Bobyk, K;Ghosh, P
通讯作者：
Ghosh, P
周质衔接蛋白 AcrA 和 AcrE 中的冗余提供了弹性和输出多药物流出底物的能力。
DOI：
10.1093/jac/dkt481
发表时间：
2014
期刊：
The Journal of antimicrobial chemotherapy
影响因子：
--
作者：
Helen E. Smith;Jessica M. A. Blair
通讯作者：
Jessica M. A. Blair