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Pisoni LA, Semple SJ, Liu S, Sykes MJ, Venter H. Combined Structure- and Ligand-Based Approach for the Identification of Inhibitors of AcrAB-TolC in Escherichia coli. ACS Infect Dis 2023; 9:2504-2522. [PMID: 37888944 DOI: 10.1021/acsinfecdis.3c00350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2023]
Abstract
The inhibition of efflux pumps is a promising approach to combating multidrug-resistant bacteria. We have developed a combined structure- and ligand-based model, using OpenEye software, for the identification of inhibitors of AcrB, the inner membrane protein component of the AcrAB-TolC efflux pump in Escherichia coli. From a database of 1391 FDA-approved drugs, 23 compounds were selected to test for efflux inhibition in E. coli. Seven compounds, including ivacaftor (25), butenafine (19), naftifine (27), pimozide (30), thioridazine (35), trifluoperazine (37), and meloxicam (26), enhanced the activity of at least one antimicrobial substrate and inhibited the efflux pump-mediated removal of the substrate Nile Red from cells. Ivacaftor (25) inhibited efflux dose dependently, had no effect on an E. coli strain with genomic deletion of the gene encoding AcrB, and did not damage the bacterial outer membrane. In the presence of a sub-minimum inhibitory concentration (MIC) of the outer membrane permeabilizer colistin, ivacaftor at 1 μg/mL reduced the MICs of erythromycin and minocycline by 4- to 8-fold. The identification of seven potential AcrB inhibitors shows the merits of a combined structure- and ligand-based approach to virtual screening.
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Affiliation(s)
- Lily A Pisoni
- Health and Biomedical Innovation, Clinical and Health Sciences, University of South Australia, Adelaide, South Australia 5000, Australia
- Quality Use of Medicines and Pharmacy Research Centre, Clinical and Health Sciences, University of South Australia, Adelaide, South Australia 5000, Australia
| | - Susan J Semple
- Quality Use of Medicines and Pharmacy Research Centre, Clinical and Health Sciences, University of South Australia, Adelaide, South Australia 5000, Australia
| | - Sida Liu
- Health and Biomedical Innovation, Clinical and Health Sciences, University of South Australia, Adelaide, South Australia 5000, Australia
| | - Matthew J Sykes
- Health and Biomedical Innovation, Clinical and Health Sciences, University of South Australia, Adelaide, South Australia 5000, Australia
| | - Henrietta Venter
- Health and Biomedical Innovation, Clinical and Health Sciences, University of South Australia, Adelaide, South Australia 5000, Australia
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Maher C, Hassan KA. The Gram-negative permeability barrier: tipping the balance of the in and the out. mBio 2023; 14:e0120523. [PMID: 37861328 PMCID: PMC10746187 DOI: 10.1128/mbio.01205-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2023] Open
Abstract
Gram-negative bacteria are intrinsically resistant to many antibiotics, due in large part to the permeability barrier formed by their cell envelope. The complex and synergistic interplay of the two Gram-negative membranes and active efflux prevents the accumulation of a diverse range of compounds that are effective against Gram-positive bacteria. A lack of detailed information on how components of the cell envelope contribute to this has been identified as a key barrier to the rational development of new antibiotics with efficacy against Gram-negative species. This review describes the current understanding of the role of the different components of the Gram-negative cell envelope in preventing compound accumulation and the state of efforts to describe properties that allow compounds to overcome this barrier and apply them to the development of new broad-spectrum antibiotics.
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Affiliation(s)
- Claire Maher
- College of Engineering, Science and Environment, University of Newcastle, Newcastle, Australia
- ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, Australia
| | - Karl A. Hassan
- College of Engineering, Science and Environment, University of Newcastle, Newcastle, Australia
- ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, Australia
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3
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Trampari E, Prischi F, Vargiu AV, Abi-Assaf J, Bavro VN, Webber MA. Functionally distinct mutations within AcrB underpin antibiotic resistance in different lifestyles. NPJ ANTIMICROBIALS AND RESISTANCE 2023; 1:2. [PMID: 38686215 PMCID: PMC11057200 DOI: 10.1038/s44259-023-00001-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 02/27/2023] [Indexed: 05/02/2024]
Abstract
Antibiotic resistance is a pressing healthcare challenge and is mediated by various mechanisms, including the active export of drugs via multidrug efflux systems, which prevent drug accumulation within the cell. Here, we studied how Salmonella evolved resistance to two key antibiotics, cefotaxime and azithromycin, when grown planktonically or as a biofilm. Resistance to both drugs emerged in both conditions and was associated with different substitutions within the efflux-associated transporter, AcrB. Azithromycin exposure selected for an R717L substitution, while cefotaxime for Q176K. Additional mutations in ramR or envZ accumulated concurrently with the R717L or Q176K substitutions respectively, resulting in clinical resistance to the selective antibiotics and cross-resistance to other drugs. Structural, genetic, and phenotypic analysis showed the two AcrB substitutions confer their benefits in profoundly different ways. R717L reduces steric barriers associated with transit through the substrate channel 2 of AcrB. Q176K increases binding energy for cefotaxime, improving recognition in the distal binding pocket, resulting in increased efflux efficiency. Finally, we show the R717 substitution is present in isolates recovered around the world.
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Affiliation(s)
- Eleftheria Trampari
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk NR4 7UQ UK
| | - Filippo Prischi
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ UK
| | - Attilio V. Vargiu
- Department of Physics, University of Cagliari, S. P. 8, km. 0.700, 09042 Monserrato, Italy
| | - Justin Abi-Assaf
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk NR4 7UQ UK
| | - Vassiliy N. Bavro
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ UK
| | - Mark A. Webber
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk NR4 7UQ UK
- Medical School, University of East Anglia, Norwich Research Park, Norwich, Norfolk NR4 7UA UK
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Athar M, Gervasoni S, Catte A, Basciu A, Malloci G, Ruggerone P, Vargiu AV. Tripartite efflux pumps of the RND superfamily: what did we learn from computational studies? MICROBIOLOGY (READING, ENGLAND) 2023; 169. [PMID: 36972322 DOI: 10.1099/mic.0.001307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
Bacterial resistance to antibiotics has been long recognized as a priority to address for human health. Among all micro-organisms, the so-called multi-drug resistant (MDR) bacteria, which are resistant to most, if not all drugs in our current arsenal, are particularly worrisome. The World Health Organization has prioritized the ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter species) pathogens, which include four Gram-negative bacterial species. In these bacteria, active extrusion of antimicrobial compounds out of the cell by means of 'molecular guns' known as efflux pumps is a main determinant of MDR phenotypes. The resistance-nodulation-cell division (RND) superfamily of efflux pumps connecting the inner and outer membrane in Gram-negative bacteria is crucial to the onset of MDR and virulence, as well as biofilm formation. Thus, understanding the molecular basis of the interaction of antibiotics and inhibitors with these pumps is key to the design of more effective therapeutics. With the aim to contribute to this challenge, and complement and inspire experimental research, in silico studies on RND efflux pumps have flourished in recent decades. Here, we review a selection of such investigations addressing the main determinants behind the polyspecificity of these pumps, the mechanisms of substrate recognition, transport and inhibition, as well as the relevance of their assembly for proper functioning, and the role of protein-lipid interactions. The journey will end with a perspective on the role of computer simulations in addressing the challenges posed by these beautifully complex machineries and in supporting the fight against the spread of MDR bacteria.
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Affiliation(s)
- Mohd Athar
- Physics Department, University of Cagliari, Cittadella Universitaria, SP 8 km 0.700, 09042, Monserrato (CA), Italy
| | - Silvia Gervasoni
- Physics Department, University of Cagliari, Cittadella Universitaria, SP 8 km 0.700, 09042, Monserrato (CA), Italy
| | - Andrea Catte
- Physics Department, University of Cagliari, Cittadella Universitaria, SP 8 km 0.700, 09042, Monserrato (CA), Italy
| | - Andrea Basciu
- Physics Department, University of Cagliari, Cittadella Universitaria, SP 8 km 0.700, 09042, Monserrato (CA), Italy
| | - Giuliano Malloci
- Physics Department, University of Cagliari, Cittadella Universitaria, SP 8 km 0.700, 09042, Monserrato (CA), Italy
| | - Paolo Ruggerone
- Physics Department, University of Cagliari, Cittadella Universitaria, SP 8 km 0.700, 09042, Monserrato (CA), Italy
| | - Attilio Vittorio Vargiu
- Physics Department, University of Cagliari, Cittadella Universitaria, SP 8 km 0.700, 09042, Monserrato (CA), Italy
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5
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Peña-Varas C, Kanstrup C, Vergara-Jaque A, González-Avendaño M, Crocoll C, Mirza O, Dreyer I, Nour-Eldin H, Ramírez D. Structural Insights into the Substrate Transport Mechanisms in GTR Transporters through Ensemble Docking. Int J Mol Sci 2022; 23:ijms23031595. [PMID: 35163519 PMCID: PMC8836200 DOI: 10.3390/ijms23031595] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 01/11/2022] [Accepted: 01/19/2022] [Indexed: 02/04/2023] Open
Abstract
Glucosinolate transporters (GTRs) are part of the nitrate/peptide transporter (NPF) family, members of which also transport specialized secondary metabolites as substrates. Glucosinolates are defense compounds derived from amino acids. We selected 4-methylthiobutyl (4MTB) and indol-3-ylmethyl (I3M) glucosinolates to study how GTR1 from Arabidopsis thaliana transports these substrates in computational simulation approaches. The designed pipeline reported here includes massive docking of 4MTB and I3M in an ensemble of GTR1 conformations (in both inward and outward conformations) extracted from molecular dynamics simulations, followed by clustered and substrate–protein interactions profiling. The identified key residues were mutated, and their role in substrate transport was tested. We were able to identify key residues that integrate a major binding site of these substrates, which is critical for transport activity. In silico approaches employed here represent a breakthrough in the plant transportomics field, as the identification of key residues usually takes a long time if performed from a purely wet-lab experimental perspective. The inclusion of structural bioinformatics in the analyses of plant transporters significantly speeds up the knowledge-gaining process and optimizes valuable time and resources.
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Affiliation(s)
- Carlos Peña-Varas
- Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Llano Subercaseaux 2801-piso 6, Santiago 8900000, Chile;
| | - Christa Kanstrup
- DynaMo Center, Department of Plant and Environmental Sciences, University of Copenhagen, 1871 Frederiksberg, Denmark; (C.K.); (C.C.); (H.N.-E.)
| | - Ariela Vergara-Jaque
- Center for Bioinformatics, Simulation and Modeling (CBSM), Faculty of Engineering, Campus Talca, Universidad de Talca, 1 Poniente No. 1141, Casilla 721, Talca 3460000, Chile; (A.V.-J.); (M.G.-A.); (I.D.)
| | - Mariela González-Avendaño
- Center for Bioinformatics, Simulation and Modeling (CBSM), Faculty of Engineering, Campus Talca, Universidad de Talca, 1 Poniente No. 1141, Casilla 721, Talca 3460000, Chile; (A.V.-J.); (M.G.-A.); (I.D.)
| | - Christoph Crocoll
- DynaMo Center, Department of Plant and Environmental Sciences, University of Copenhagen, 1871 Frederiksberg, Denmark; (C.K.); (C.C.); (H.N.-E.)
| | - Osman Mirza
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark;
| | - Ingo Dreyer
- Center for Bioinformatics, Simulation and Modeling (CBSM), Faculty of Engineering, Campus Talca, Universidad de Talca, 1 Poniente No. 1141, Casilla 721, Talca 3460000, Chile; (A.V.-J.); (M.G.-A.); (I.D.)
| | - Hussam Nour-Eldin
- DynaMo Center, Department of Plant and Environmental Sciences, University of Copenhagen, 1871 Frederiksberg, Denmark; (C.K.); (C.C.); (H.N.-E.)
| | - David Ramírez
- Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Llano Subercaseaux 2801-piso 6, Santiago 8900000, Chile;
- Research Center for the Development of Novel Therapeutic Alternatives for Alcohol Use Disorders, Santiago 8900000, Chile
- Correspondence: ; Tel.: +56-(22)-3036667
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Pyridylpiperazine-based allosteric inhibitors of RND-type multidrug efflux pumps. Nat Commun 2022; 13:115. [PMID: 35013254 PMCID: PMC8749003 DOI: 10.1038/s41467-021-27726-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Accepted: 12/02/2021] [Indexed: 12/30/2022] Open
Abstract
Efflux transporters of the RND family confer resistance to multiple antibiotics in Gram-negative bacteria. Here, we identify and chemically optimize pyridylpiperazine-based compounds that potentiate antibiotic activity in E. coli through inhibition of its primary RND transporter, AcrAB-TolC. Characterisation of resistant E. coli mutants and structural biology analyses indicate that the compounds bind to a unique site on the transmembrane domain of the AcrB L protomer, lined by key catalytic residues involved in proton relay. Molecular dynamics simulations suggest that the inhibitors access this binding pocket from the cytoplasm via a channel exclusively present in the AcrB L protomer. Thus, our work unveils a class of allosteric efflux-pump inhibitors that likely act by preventing the functional catalytic cycle of the RND pump. Efflux transporters of the RND family confer resistance to multiple antibiotics in Gram-negative bacteria. Here, the authors identify pyridylpiperazine-based compounds that potentiate antibiotic activity in E. coli through allosteric inhibition of its primary RND transporter.
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Moringa oleifera polysaccharides regulates caecal microbiota and small intestinal metabolic profile in C57BL/6 mice. Int J Biol Macromol 2021; 182:595-611. [PMID: 33836198 DOI: 10.1016/j.ijbiomac.2021.03.144] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 03/03/2021] [Accepted: 03/23/2021] [Indexed: 02/07/2023]
Abstract
This study investigated the effects of Moringa oleifera polysaccharides (MOP) on the serum indexes, small intestinal morphology, small intestinal metabolic profile, and caecal microbiota of mice. A new type of polysaccharides with 104,031 Da molecular weight and triple helix structure was isolated from M. oleifera leaves for in vivo experiment. Forty male SPF C57BL/6 mice aged 4 weeks were average divided into four groups randomly according to the MOP gavaged daily (0, 20, 40 and 60 mg/kg body weight MOP). After a 7-day preliminary trial period and a 28-day official trial period, the mice were slaughtered. Results showed that MOP reduced glucose, total cholesterol, and malondialdehyde. It also improved superoxide dismutase and catalase in serum (P < 0.05). For small intestinal morphology, MOP improved the villi length and crypt depth in both ileum and jejunum (P < 0.05); the ratio of villi length to crypt depth in jejunum increased (P < 0.05). MOP could cause the increase of beneficial bacteria and the decrease of harmful bacteria in caecum, further affecting the function of microbiota. In addition, MOP regulated 114 metabolites enriched in the pathway related to the synthesis and metabolism of micromolecules. In sum, MOP exerted positive effects on the serum indexes and intestinal health of mice.
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Rathi E, Kumar A, Kini SG. Computational approaches in efflux pump inhibitors: current status and prospects. Drug Discov Today 2020; 25:1883-1890. [PMID: 32712312 DOI: 10.1016/j.drudis.2020.07.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 07/02/2020] [Accepted: 07/13/2020] [Indexed: 01/02/2023]
Abstract
Treatment of bacterial infections is currently threatened by the development of antibiotic resistance and a poor pipeline of new antibiotics. Efflux pumps (EPs) are an integral part of the defense machinery of bacteria, preventing the entry of molecules, such as antibiotics, into the intracellular environment and resulting in antibiotic resistance. Therefore, research has focused on the discovery of novel EP inhibitors (EPIs), such as PAβN, D13-9001, and MBX2319. however, there are still no US Food and Drug Administration (FDA)-approved drugs targeting EPs because of the inadequate assimilation of the inhibitors. Here, we discuss the use of computational approaches for molecular mechanistic studies of EPIs to help direct future research.
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Affiliation(s)
- Ekta Rathi
- Department of Pharmaceutical Chemistry, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, 576104, India
| | - Avinash Kumar
- Department of Pharmaceutical Chemistry, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, 576104, India
| | - Suvarna G Kini
- Department of Pharmaceutical Chemistry, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, 576104, India.
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Abstract
Efflux is an important mechanism in Gram-negative bacteria conferring multidrug resistance. Inhibition of efflux is an encouraging strategy to restore the antibacterial activity of antibiotics. Chlorpromazine and amitriptyline have been shown to behave as efflux inhibitors. However, their mode of action is poorly understood. Exposure of Salmonella enterica serovar Typhimurium and Escherichia coli to chlorpromazine selected for mutations within genes encoding RamR and MarR, regulators of the multidrug tripartite efflux pump AcrAB-TolC. Further experiments with S. Typhimurium containing AcrB D408A (a nonfunctional efflux pump) and chlorpromazine or amitriptyline resulted in the reversion of the mutant acrB allele to the wild type. Together, this suggests these drugs are AcrB efflux substrates. Subsequent docking studies with AcrB from S. Typhimurium and E. coli, followed by molecular dynamics simulations and free energy calculations showed that chlorpromazine and amitriptyline bind at the hydrophobic trap, a preferred binding site for substrates and inhibitors within the distal binding pocket of AcrB. Based on these simulations, we suggest that chlorpromazine and amitriptyline inhibit AcrB-mediated efflux by interfering with substrate binding. Our findings provide evidence that these drugs are substrates and inhibitors of AcrB, yielding molecular details of their mechanism of action and informing drug discovery of new efflux inhibitors.IMPORTANCE Efflux pumps of the resistance nodulation-cell division (RND) superfamily are major contributors to multidrug resistance for most of the Gram-negative ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogens. The development of inhibitors of these pumps would be highly desirable; however, several issues have thus far hindered all efforts at designing new efflux inhibitory compounds devoid of adverse effects. An alternative route to de novo design relies on the use of marketed drugs, for which side effects on human health have been already assessed. In this work, we provide experimental evidence that the antipsychotic drugs chlorpromazine and amitriptyline are inhibitors of the AcrB transporter, the engine of the major RND efflux pumps in Escherichia coli and Salmonella enterica serovar Typhimurium. Furthermore, in silico calculations have provided a molecular-level picture of the inhibition mechanism, allowing rationalization of experimental data and paving the way for similar studies with other classes of marketed compounds.
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10
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Atzori A, Malloci G, Cardamone F, Bosin A, Vargiu AV, Ruggerone P. Molecular Interactions of Carbapenem Antibiotics with the Multidrug Efflux Transporter AcrB of Escherichia coli. Int J Mol Sci 2020; 21:E860. [PMID: 32013182 PMCID: PMC7037162 DOI: 10.3390/ijms21030860] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 01/26/2020] [Indexed: 12/22/2022] Open
Abstract
The drug/proton antiporter AcrB, engine of the major efflux pump AcrAB(Z)-TolC of Escherichia coli and other bacteria, is characterized by its impressive ability to transport chemically diverse compounds, conferring a multi-drug resistance (MDR) phenotype. Although hundreds of small molecules are known to be AcrB substrates, only a few co-crystal structures are available to date. Computational methods have been therefore intensively employed to provide structural and dynamical fingerprints related to transport and inhibition of AcrB. In this work, we performed a systematic computational investigation to study the interaction between representative carbapenem antibiotics and AcrB. We focused on the interaction of carbapenems with the so-called distal pocket, a region known for its importance in binding inhibitors and substrates of AcrB. Our findings reveal how the different physico-chemical nature of these antibiotics is reflected on their binding preference for AcrB. The molecular-level information provided here could help design new antibiotics less susceptible to the efflux mechanism.
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Affiliation(s)
| | - Giuliano Malloci
- Department of Physics, University of Cagliari, 09042 Monserrato (CA), Italy; (A.A.); (F.C.); (A.B.); (P.R.)
| | | | | | - Attilio Vittorio Vargiu
- Department of Physics, University of Cagliari, 09042 Monserrato (CA), Italy; (A.A.); (F.C.); (A.B.); (P.R.)
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Wang Y, Alenzy R, Song D, Liu X, Teng Y, Mowla R, Ma Y, Polyak SW, Venter H, Ma S. Structural optimization of natural product nordihydroguaretic acid to discover novel analogues as AcrB inhibitors. Eur J Med Chem 2019; 186:111910. [PMID: 31801655 DOI: 10.1016/j.ejmech.2019.111910] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 11/12/2019] [Accepted: 11/24/2019] [Indexed: 12/27/2022]
Abstract
Drug efflux pumps confer multidrug resistance to dangerous bacterial pathogens which makes these proteins promising drug targets. Herein, we present initial chemical optimization and structure-activity relationship (SAR) data around a previously described efflux pump inhibitor, nordihydroguaretic acid (NDGA). Four series of novel NDGA analogues that target Escherichia coli AcrB were designed, synthesized and evaluated for their ability to potentiate the activity of antibiotics, to inhibit AcrB-mediated substrate efflux and reduce off-target activity. Nine novel structures were identified that increased the efficacy of a panel of antibiotics, inhibited drug efflux and reduced permeabilization of the bacterial outer and inner membranes. Among them, WA7, WB11 and WD6 possessing broad-spectrum antimicrobial sensitization activity were identified as NDGA analogues with favorable properties as potential AcrB inhibitors, demonstrating moderate improvement in potency as compared to NDGA. In particular, WD6 was the most broadly active analogue improving the activity of all four classes of antibacterials tested.
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Affiliation(s)
- Yinhu Wang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, Jinan, 250012, China; School of Pharmacy, Liaocheng University, Liaocheng, China
| | - Rawaf Alenzy
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA, 5000, Australia; Department of Medical Laboratory, College of Applied Medical Sciences-Shaqra, Shaqra University, 11961, Saudi Arabia
| | - Di Song
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, Jinan, 250012, China
| | - Xingbang Liu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, Jinan, 250012, China
| | - Yuetai Teng
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, Jinan, 250012, China
| | - Rumana Mowla
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA, 5000, Australia
| | - Yingang Ma
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, Jinan, 250012, China
| | - Steven W Polyak
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA, 5000, Australia
| | - Henrietta Venter
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA, 5000, Australia.
| | - Shutao Ma
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, Jinan, 250012, China.
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