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Rouchidane Eyitayo A, Daury L, Priault M, Manon S. The membrane insertion of the pro-apoptotic protein Bax is a Tom22-dependent multi-step process: a study in nanodiscs. Cell Death Discov 2024; 10:335. [PMID: 39043635 PMCID: PMC11266675 DOI: 10.1038/s41420-024-02108-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 07/11/2024] [Accepted: 07/17/2024] [Indexed: 07/25/2024] Open
Abstract
Membrane insertion of the pro-apoptotic protein Bax was investigated by setting up cell-free synthesis of full-length Bax in the presence of pre-formed nanodiscs. While Bax was spontaneously poorly inserted in nanodiscs, co-synthesis with the mitochondrial receptor Tom22 stimulated Bax membrane insertion. The initial interaction of Bax with the lipid bilayer exposed the hydrophobic GALLL motif in Hα1 leading to Bax precipitation through hydrophobic interactions. The same motif was recognized by Tom22, triggering conformational changes leading to the extrusion and the ensuing membrane insertion of the C-terminal hydrophobic Hα9. Tom22 was also required for Bax-membrane insertion after Bax was activated either by BH3-activators or by its release from Bcl-xL by WEHI-539. The effect of Tom22 was impaired by D154Y substitution in Bax-Hα7 and T174P substitution in Bax-Hα9, which are found in several tumors. Conversely, a R9E substitution promoted a spontaneous insertion of Bax in nanodiscs, in the absence of Tom22. Both Tom22-activated Bax and BaxR9E alone permeabilized liposomes to dextran-10kDa and formed ~5-nm-diameter pores in nanodiscs. The concerted regulation of Bax membrane insertion by Tom22 and BH3-activators is discussed.
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Affiliation(s)
| | - Laetitia Daury
- CNRS, Université de Bordeaux, UMR 5248, CBMN, Pessac, France
| | - Muriel Priault
- CNRS, Université de Bordeaux, UMR 5095, IBGC, Bordeaux, France
| | - Stéphen Manon
- CNRS, Université de Bordeaux, UMR 5095, IBGC, Bordeaux, France.
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2
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Ikujuni AP, Dhar R, Cordova A, Bowman AM, Noga S, Slusky JSG. Discovery and Characterization of Two Folded Intermediates for Outer Membrane Protein TolC Biogenesis. J Mol Biol 2024; 436:168652. [PMID: 38871177 DOI: 10.1016/j.jmb.2024.168652] [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] [Received: 11/22/2023] [Revised: 05/12/2024] [Accepted: 06/06/2024] [Indexed: 06/15/2024]
Abstract
TolC is the outer membrane protein responsible for antibiotic efflux in E. coli. Compared to other outer membrane proteins it has an unusual fold and has been shown to fold independently of commonly used periplasmic chaperones, SurA and Skp. Here we find that the assembly of TolC involves the formation of two folded intermediates using circular dichroism, gel electrophoresis, site-specific disulfide bond formation and radioactive labeling. First the TolC monomer folds, and then TolC assembles into a trimer both in detergent-free buffer and in the presence of detergent micelles. We find that a TolC trimer also forms in the periplasm and is present in the periplasm before it inserts in the outer membrane. The monomeric and trimeric folding intermediates may be used in the future to develop a new approach to antibiotic efflux pump inhibition by targeting the assembly pathway of TolC.
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Affiliation(s)
- Ayotunde Paul Ikujuni
- Department of Molecular Biosciences, The University of Kansas, 1200 Sunnyside Ave, Lawrence, KS 66045, United States
| | - Rik Dhar
- Department of Molecular Biosciences, The University of Kansas, 1200 Sunnyside Ave, Lawrence, KS 66045, United States
| | - Andres Cordova
- Department of Molecular Biosciences, The University of Kansas, 1200 Sunnyside Ave, Lawrence, KS 66045, United States
| | - Alexander M Bowman
- Department of Molecular Biosciences, The University of Kansas, 1200 Sunnyside Ave, Lawrence, KS 66045, United States
| | - Sarah Noga
- Department of Molecular Biosciences, The University of Kansas, 1200 Sunnyside Ave, Lawrence, KS 66045, United States
| | - Joanna S G Slusky
- Department of Molecular Biosciences, The University of Kansas, 1200 Sunnyside Ave, Lawrence, KS 66045, United States; Computational Biology Program, The University of Kansas, 2030 Becker Dr., Lawrence, KS 66045-7534, United States.
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3
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Ammazzalorso A, Granese A, De Filippis B. Recent trends and challenges to overcome Pseudomonas aeruginosa infections. Expert Opin Ther Pat 2024; 34:493-509. [PMID: 38683024 DOI: 10.1080/13543776.2024.2348602] [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] [Received: 01/10/2024] [Accepted: 04/24/2024] [Indexed: 05/01/2024]
Abstract
INTRODUCTION Pseudomonas aeruginosa (PA) is a Gram-negative bacterium that can cause a wide range of severe infections in immunocompromised patients. The most difficult challenge is due to its ability to rapidly develop multi drug-resistance. New strategies are urgently required to improve the outcome of patients with PA infections. The present patent review highlights the new molecules acting on different targets involved in the antibiotic resistance. AREA COVERED This review offers an insight into new potential PA treatment disclosed in patent literature. From a broad search of documents claiming new PA inhibitors, we selected and summarized molecules that showed in vitro and in vivo activity against PA spp. in the period 2020 and 2023. We collected the search results basing on the targets explored. EXPERT OPINION This review examined the main patented compounds published in the last three years, with regard to the structural novelty and the identification of innovative targets. The main areas of antibiotic resistance have been explored. The compounds are structurally unrelated to earlier antibiotics, characterized by a medium-high molecular weight and the presence of heterocycle rings. Peptides and antibodies have also been reported as potential alternatives to chemical treatment, hereby expanding the therapeutic possibilities in this field.
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Affiliation(s)
| | - Arianna Granese
- Department of Drug Chemistry and Technology, "Sapienza" University of Rome, Rome, Italy
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4
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Ganjo AR, Balaky STJ, Mawlood AH, Smail SB, Shabila NP. Characterization of genes related to the efflux pump and porin in multidrug-resistant Escherichia coli strains isolated from patients with COVID-19 after secondary infection. BMC Microbiol 2024; 24:122. [PMID: 38600509 PMCID: PMC11005145 DOI: 10.1186/s12866-024-03283-8] [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] [Received: 07/28/2023] [Accepted: 03/28/2024] [Indexed: 04/12/2024] Open
Abstract
BACKGROUND Escherichia coli (E. coli) is a multidrug resistant opportunistic pathogen that can cause secondary bacterial infections in patients with COVID-19. This study aimed to determine the antimicrobial resistance profile of E. coli as a secondary bacterial infection in patients with COVID-19 and to assess the prevalence and characterization of genes related to efflux pumps and porin. METHODS A total of 50 nonduplicate E. coli isolates were collected as secondary bacterial infections in COVID-19 patients. The isolates were cultured from sputum samples. Confirmation and antibiotic susceptibility testing were conducted by Vitek 2. PCR was used to assess the prevalence of the efflux pump and porin-related genes in the isolates. The phenotypic and genotypic evolution of antibiotic resistance genes related to the efflux pump was evaluated. RESULTS The E. coli isolates demonstrated high resistance to ampicillin (100%), cefixime (62%), cefepime (62%), amoxicillin-clavulanic acid (60%), cefuroxime (60%), and ceftriaxone (58%). The susceptibility of E. coli to ertapenem was greatest (92%), followed by imipenem (88%), meropenem (86%), tigecycline (80%), and levofloxacin (76%). Regarding efflux pump gene combinations, there was a significant association between the acrA gene and increased resistance to levofloxacin, between the acrB gene and decreased resistance to meropenem and increased resistance to levofloxacin, and between the ompF and ompC genes and increased resistance to gentamicin. CONCLUSIONS The antibiotics ertapenem, imipenem, meropenem, tigecycline, and levofloxacin were effective against E. coli in patients with COVID-19. Genes encoding efflux pumps and porins, such as acrA, acrB, and outer membrane porins, were highly distributed among all the isolates. Efflux pump inhibitors could be alternative antibiotics for restoring tetracycline activity in E. coli isolates.
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Affiliation(s)
- Aryan R Ganjo
- Department of Clinical Analysis, College of Pharmacy, Hawler Medical University, Erbil, Kurdistan Region, Iraq
- Department of Medical Analysis, Faculty of Applied Science, Tishk International University, Erbil, Iraq
| | - Salah Tofik Jalal Balaky
- Department of Medical Analysis, Faculty of Applied Science, Tishk International University, Erbil, Iraq.
- Department of Medical Microbiology, College of Health Sciences, Hawler Medical University, Erbil, Kurdistan Region, Iraq.
| | - Ahang Hasan Mawlood
- Department of Medical Microbiology, College of Health Sciences, Hawler Medical University, Erbil, Kurdistan Region, Iraq
- Department of Medical Laboratory Technique, College of Medical Technology, AL-Kitab University, Kirkuk, Iraq
| | | | - Nazar P Shabila
- College of Health Sciences, Catholic University in Erbil, Erbil, Kurdistan Region, Iraq
- Department of Community Medicine, College of Medicine, Hawler Medical University, Erbil, Iraq
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5
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Dwivedi GR, Pathak N, Tiwari N, Negi AS, Kumar A, Pal A, Sharma A, Darokar MP. Synergistic Antibacterial Activity of Gallic Acid Based Chalcone Indl 2 by Inhibiting Efflux Pump Transporters. Chem Biodivers 2024; 21:e202301820. [PMID: 38372508 DOI: 10.1002/cbdv.202301820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 02/16/2024] [Accepted: 02/17/2024] [Indexed: 02/20/2024]
Abstract
As a part of novel discovery of drugs from natural resources, present study was undertaken to explore the antibacterial potential of chalcone Indl-2 in combination with different group of antibiotics. MIC of antibiotics was reduced up to eight folds against the different cultures of E. coli by both chalcones. Among the two compounds, the i. e. 1-(3', 4,'5'-trimethoxyphenyl)-3-(3-Indyl)-prop-2-enone (6, Indl-2), a chalcone derivative of gallic acid (Indl-2) was better along with tetracycline (TET) worked synergistically and was found to inhibit efflux transporters as obvious by ethidium bromide efflux confirmed by ATPase assays and docking studies. In combination, Indl-2 kills the MDREC-KG4 cells, post-antibiotic effect (PAE) of TET was prolonged and mutant prevention concentration (MPC) of TET was also decreased. In-vivo studies revealed that Indl-2 reduces the concentration of TNF-α. In acute oral toxicity study, Indl-2 was non-toxic and well tolerated up-to dose of 2000 mg/kg. Perhaps, the study is going to report gallic acid derived chalcone as synergistic agent acting via inhibiting the primary efflux pumps.
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Affiliation(s)
- Gaurav Raj Dwivedi
- Biotechnology Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Near Kukrail Picnic Spot, P.O. CIMAP, Lucknow, 226015, India
- Microbiology Department, ICMR-Regional Medical Research Centre, Gorakhpur, 273013, U.P., India
| | - Nandini Pathak
- Phytochemistry Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Near Kukrail Picnic Spot, P.O. CIMAP, Lucknow, 226015, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, U.P. - 201002, India
| | - Nimisha Tiwari
- Biotechnology Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Near Kukrail Picnic Spot, P.O. CIMAP, Lucknow, 226015, India
| | - Arvind Singh Negi
- Phytochemistry Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Near Kukrail Picnic Spot, P.O. CIMAP, Lucknow, 226015, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, U.P. - 201002, India
| | - Akhil Kumar
- Biotechnology Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Near Kukrail Picnic Spot, P.O. CIMAP, Lucknow, 226015, India
| | - Anirban Pal
- Biotechnology Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Near Kukrail Picnic Spot, P.O. CIMAP, Lucknow, 226015, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, U.P. - 201002, India
| | - Ashok Sharma
- Biotechnology Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Near Kukrail Picnic Spot, P.O. CIMAP, Lucknow, 226015, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, U.P. - 201002, India
| | - Mahendra P Darokar
- Biotechnology Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Near Kukrail Picnic Spot, P.O. CIMAP, Lucknow, 226015, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, U.P. - 201002, India
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6
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Wilhelm J, Pos KM. Molecular insights into the determinants of substrate specificity and efflux inhibition of the RND efflux pumps AcrB and AdeB. MICROBIOLOGY (READING, ENGLAND) 2024; 170:001438. [PMID: 38358391 PMCID: PMC10924465 DOI: 10.1099/mic.0.001438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 01/30/2024] [Indexed: 02/16/2024]
Abstract
Gram-negative bacterial members of the Resistance Nodulation and cell Division (RND) superfamily form tripartite efflux pump systems that span the cell envelope. One of the intriguing features of the multiple drug efflux members of this superfamily is their ability to recognize different classes of antibiotics, dyes, solvents, bile salts, and detergents. This review provides an overview of the molecular mechanisms of multiple drug efflux catalysed by the tripartite RND efflux system AcrAB-TolC from Eschericha coli. The determinants for sequential or simultaneous multiple substrate binding and efflux pump inhibitor binding are discussed. A comparison is made with the determinants for substrate binding of AdeB from Acinetobacter baumannii, which acts within the AdeABC multidrug efflux system. There is an apparent general similarity between the structures of AcrB and AdeB and their substrate specificity. However, the presence of distinct conformational states and different drug efflux capacities as revealed by single-particle cryo-EM and mutational analysis suggest that the drug binding and transport features exhibited by AcrB may not be directly extrapolated to the homolog AdeB efflux pump.
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Affiliation(s)
- Julia Wilhelm
- Institute of Biochemistry, Goethe-University Frankfurt, Max-von-Laue-Str. 9, D-60438 Frankfurt am Main, Germany
| | - Klaas Martinus Pos
- Institute of Biochemistry, Goethe-University Frankfurt, Max-von-Laue-Str. 9, D-60438 Frankfurt am Main, Germany
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7
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Smith BL, Fernando S, King MD. Escherichia coli resistance mechanism AcrAB-TolC efflux pump interactions with commonly used antibiotics: a molecular dynamics study. Sci Rep 2024; 14:2742. [PMID: 38302495 PMCID: PMC10834472 DOI: 10.1038/s41598-024-52536-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Accepted: 01/19/2024] [Indexed: 02/03/2024] Open
Abstract
While antibiotic resistance poses a threat from both Gram-positive bacteria (GPB) and Gram-negative bacteria (GNB), GNB pose a more imminent public health hazard globally. GNB are a threat to growing antibiotic resistance because of the complex makeup of the membrane. The AcrAB-TolC efflux pump is a known resistance mechanism of Escherichia coli (E. coli) cells. This study utilized molecular dynamics modeling to visualize some of the changes occurring at a molecular level when airborne bacteria are exposed to stress and antibiotics. This study was conducted to build upon previous experimental research showing that there is an increase in antibiotic resistance and efflux pump activity when exposed to aerosolization. AcrB and AcrAB-TolC proteins were simulated under standard and increased pressure to compare the effect of aerosolization on the binding to the three different antibiotics (puromycin (PUY), ampicillin (AMP) and sulfamethoxazole-trimethoprim (SXT)) to the AcrB binding site. Analysis such as root-mean-square deviation of atomic positions and root-mean-square fluctuation, the opening of TolC, and the significant molecular mechanics with generalized Born and surface area solvation (MM-GBSA) scores associated with specific ligands were recorded. Resistance in experimental data indicated a relationship between the docking scores and some ligand-protein interactions. Results showed that there was more flexibility in the proteins within simulations conducted under standard pressure for the AcrB protein and the full tripartite complex AcrAB-TolC, showing that increased pressure causes more rigidity. MM-GBSA scores, used to calculate the free energy of ligand-protein binding, did not show a significant change, but interestingly, the strongest MM-GBSA scores were for ligands that moved to another binding pocket and did not result in resistance or opening of the efflux pump. However, the ligand moved from the binding site and did not cause the opening of TolC to increase significantly, whereas PUY and AMP were bound to the binding site for the duration of all simulations. AMP ligands under increased pressure showed the largest change in opening of the TolC efflux pump and aligns with experimental data showing E. coli cells had the most resistance to AMP after aerosolization. These results, in addition to other real-time changes such as OM proteins and mutations of targets within the cell, could be used to delineate and mitigate antibiotic resistance mechanisms.
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Affiliation(s)
- Brooke L Smith
- Aerosol Technology Laboratory, Biological and Agricultural Engineering Department, Texas A&M University, College Station, TX, 77843, USA
| | - Sandun Fernando
- Aerosol Technology Laboratory, Biological and Agricultural Engineering Department, Texas A&M University, College Station, TX, 77843, USA
| | - Maria D King
- Aerosol Technology Laboratory, Biological and Agricultural Engineering Department, Texas A&M University, College Station, TX, 77843, USA.
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8
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Ching C, Maufront J, di Cicco A, Lévy D, Dezi M. C ool-contacts: Cryo-Electron Microscopy of Membrane Contact Sites and Their Components. CONTACT (THOUSAND OAKS (VENTURA COUNTY, CALIF.)) 2024; 7:25152564241231364. [PMID: 38410695 PMCID: PMC10895918 DOI: 10.1177/25152564241231364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 01/23/2024] [Indexed: 02/28/2024]
Abstract
Electron microscopy has played a pivotal role in elucidating the ultrastructure of membrane contact sites between cellular organelles. The advent of cryo-electron microscopy has ushered in the ability to determine atomic models of constituent proteins or protein complexes within sites of membrane contact through single particle analysis. Furthermore, it enables the visualization of the three-dimensional architecture of membrane contact sites, encompassing numerous copies of proteins, whether in vitro reconstituted or directly observed in situ using cryo-electron tomography. Nevertheless, there exists a scarcity of cryo-electron microscopy studies focused on the site of membrane contact and their constitutive proteins. This review provides an overview of the contributions made by cryo-electron microscopy to our understanding of membrane contact sites, outlines the associated limitations, and explores prospects in this field.
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Affiliation(s)
- Cyan Ching
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Laboratoire Physique des Cellules et Cancer, Paris, France
| | - Julien Maufront
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Laboratoire Physique des Cellules et Cancer, Paris, France
| | - Aurélie di Cicco
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Laboratoire Physique des Cellules et Cancer, Paris, France
| | - Daniel Lévy
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Laboratoire Physique des Cellules et Cancer, Paris, France
| | - Manuela Dezi
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Laboratoire Physique des Cellules et Cancer, Paris, France
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9
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Yu Z, Shi X, Wang Z. Structures and Efflux Mechanisms of the AcrAB-TolC Pump. Subcell Biochem 2024; 104:1-16. [PMID: 38963480 DOI: 10.1007/978-3-031-58843-3_1] [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: 07/05/2024]
Abstract
The global emergence of multidrug resistance (MDR) in gram-negative bacteria has become a matter of worldwide concern. MDR in these pathogens is closely linked to the overexpression of certain efflux pumps, particularly the resistance-nodulation-cell division (RND) efflux pumps. Inhibition of these pumps presents an attractive and promising strategy to combat antibiotic resistance, as the efflux pump inhibitors can effectively restore the potency of existing antibiotics. AcrAB-TolC is one well-studied RND efflux pump, which transports a variety of substrates, therefore providing resistance to a broad spectrum of antibiotics. To develop effective pump inhibitors, a comprehensive understanding of the structural aspect of the AcrAB-TolC efflux pump is imperative. Previous studies on this pump's structure have been limited to individual components or in vitro determination of fully assembled pumps. Recent advancements in cellular cryo-electron tomography (cryo-ET) have provided novel insights into this pump's assembly and functional mechanism within its native cell membrane environment. Here, we present a summary of the structural data regarding the AcrAB-TolC efflux pump, shedding light on its assembly pathway and operational mechanism.
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Affiliation(s)
- Zhili Yu
- Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, TX, USA
| | - Xiaodong Shi
- Jiangsu Province Key Laboratory of Anesthesiology and Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Zhao Wang
- Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, TX, USA.
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA.
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10
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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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11
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Giovagnorio F, De Vito A, Madeddu G, Parisi SG, Geremia N. Resistance in Pseudomonas aeruginosa: A Narrative Review of Antibiogram Interpretation and Emerging Treatments. Antibiotics (Basel) 2023; 12:1621. [PMID: 37998823 PMCID: PMC10669487 DOI: 10.3390/antibiotics12111621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Revised: 11/02/2023] [Accepted: 11/10/2023] [Indexed: 11/25/2023] Open
Abstract
Pseudomonas aeruginosa is a ubiquitous Gram-negative bacterium renowned for its resilience and adaptability across diverse environments, including clinical settings, where it emerges as a formidable pathogen. Notorious for causing nosocomial infections, P. aeruginosa presents a significant challenge due to its intrinsic and acquired resistance mechanisms. This comprehensive review aims to delve into the intricate resistance mechanisms employed by P. aeruginosa and to discern how these mechanisms can be inferred by analyzing sensitivity patterns displayed in antibiograms, emphasizing the complexities encountered in clinical management. Traditional monotherapies are increasingly overshadowed by the emergence of multidrug-resistant strains, necessitating a paradigm shift towards innovative combination therapies and the exploration of novel antibiotics. The review accentuates the critical role of accurate antibiogram interpretation in guiding judicious antibiotic use, optimizing therapeutic outcomes, and mitigating the propagation of antibiotic resistance. Misinterpretations, it cautions, can inadvertently foster resistance, jeopardizing patient health and amplifying global antibiotic resistance challenges. This paper advocates for enhanced clinician proficiency in interpreting antibiograms, facilitating informed and strategic antibiotic deployment, thereby improving patient prognosis and contributing to global antibiotic stewardship efforts.
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Affiliation(s)
- Federico Giovagnorio
- Department of Molecular Medicine, University of Padua, 35121 Padua, Italy; (F.G.); (S.G.P.)
| | - Andrea De Vito
- Unit of Infectious Diseases, Department of Medicine, Surgery and Pharmacy, University of Sassari, 07100 Sassari, Italy;
| | - Giordano Madeddu
- Unit of Infectious Diseases, Department of Medicine, Surgery and Pharmacy, University of Sassari, 07100 Sassari, Italy;
| | | | - Nicholas Geremia
- Unit of Infectious Diseases, Department of Clinical Medicine, Ospedale “dell’Angelo”, 30174 Venice, Italy
- Unit of Infectious Diseases, Department of Clinical Medicine, Ospedale Civile “S.S. Giovanni e Paolo”, 30122 Venice, Italy
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12
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Shakibaie MR, Modaresi F, Azizi O, Tadjrobehkar O, Ghaemi MM. Amphiphilic peptide Mastoparan-B induces conformational changes within the AdeB efflux pump, down-regulates adeB gene expression, and restores antibiotic susceptibility in an MDR strain of Acinetobacter baumannii. Proteins 2023; 91:1205-1221. [PMID: 37455426 DOI: 10.1002/prot.26539] [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] [Received: 12/16/2022] [Revised: 05/11/2023] [Accepted: 05/30/2023] [Indexed: 07/18/2023]
Abstract
Mastoparan B (MP-B) is an amphiphilic peptide with a potent antimicrobial activity against most Gram-negative bacteria. However, there is little information available on the inhibition of the Acinetobacter baumannii resistance-nodulation-cell-division (RND) efflux pump using this antimicrobial peptide. Here, we carried out a series of in-silico experiments to find the mechanisms underlying the anti-efflux activity of MP-B using a multi-drug resistant (MDR) strain of A. baumannii (AB). According to our findings, MP-B demonstrated a potent antibacterial activity against an MDR-AB (minimum inhibitory concentration [MIC] = 1 μg/mL) followed by a 20-fold reduction in the adeB gene expression in the presence of sub-MIC of this peptide. Using Groningen Machine for Chemicals Simulation (GROMACS) via PyMOL Graphical User Interface (GUI), (we observed that, the AdeB transporter had conserved helix-turn-helix regions and a tight pore rich in Phe and Ala residues. To understand how inhibition of the AdeB is achieved, we generated 20 apo-MP-B poses using the InterPep and SiteMap tools. The high-quality model was created by homology modeling and used for docking via AutoDock/Vina to identify the MP-B binding sites. We established that the most apo-MP-B formed H-bonds to the backbone of five amino acids in the Helix-5. As a result, the dihedral angles of the involved amino acids shift by 9.0-9.6 Ǻ, causing a change in the conformation of the AdeB protein. This led to helix conformation stereoisomerization and block the AdeB activity. MP-B presumably has dual mechanisms. (1) It blocks the AdeB transporter by changing its conformation. (2) MP-B influences the adeB gene expression by binding to G-protein which laterally controls efflux regulators like MarA, RamA, SoxS, and Rob proteins.
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Affiliation(s)
- Mohammad Reza Shakibaie
- Department of Microbiology and Virology, Kerman University of Medical Sciences, Kerman, Iran
- Gastroenterology Hepatology Research Center, Institute of Basic and Clinical Physiology, Kerman University of Medical Sciences, Kerman, Iran
| | - Farzan Modaresi
- Department of Microbiology, School of Medicine, Jahrom University of Medical Sciences, Jahrom, Iran
| | - Omid Azizi
- Department of Laboratory Sciences, and Health Sciences Research center, Torbat Heydariyeh University of Medical Sciences, Torbate Heydarieh, Iran
| | - Omid Tadjrobehkar
- Department of Microbiology and Virology, Kerman University of Medical Sciences, Kerman, Iran
| | - Mohammad Mehdi Ghaemi
- Medical Informatics Research Center, Institute for Futures Studies in Health, Kerman University of Medical Sciences, Kerman, Iran
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13
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Jang S. AcrAB-TolC, a major efflux pump in Gram negative bacteria: toward understanding its operation mechanism. BMB Rep 2023; 56:326-334. [PMID: 37254571 PMCID: PMC10315565 DOI: 10.5483/bmbrep.2023-0070] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 05/18/2023] [Accepted: 05/30/2023] [Indexed: 08/27/2023] Open
Abstract
Antibiotic resistance (AR) is a silent pandemic that kills millions worldwide. Although the development of new therapeutic agents against antibiotic resistance is in urgent demand, this has presented a great challenge, especially for Gram-negative bacteria that have inherent drug-resistance mediated by impermeable outer membranes and multidrug efflux pumps that actively extrude various drugs from the bacteria. For the last two decades, multidrug efflux pumps, including AcrAB-TolC, the most clinically important efflux pump in Gram-negative bacteria, have drawn great attention as strategic targets for re-sensitizing bacteria to the existing antibiotics. This article aims to provide a concise overview of the AcrAB-TolC operational mechanism, reviewing its architecture and substrate specificity, as well as the recent development of AcrAB-TolC inhibitors. [BMB Reports 2023; 56(6): 326-334].
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Affiliation(s)
- Soojin Jang
- Department of Discovery Biology, Antibacterial Resistance Laboratory, Institut Pasteur Korea, Seongnam 13488, Korea
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14
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Badiee SA, Isu UH, Khodadadi E, Moradi M. The Alternating Access Mechanism in Mammalian Multidrug Resistance Transporters and Their Bacterial Homologs. MEMBRANES 2023; 13:568. [PMID: 37367772 DOI: 10.3390/membranes13060568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Revised: 05/23/2023] [Accepted: 05/27/2023] [Indexed: 06/28/2023]
Abstract
Multidrug resistance (MDR) proteins belonging to the ATP-Binding Cassette (ABC) transporter group play a crucial role in the export of cytotoxic drugs across cell membranes. These proteins are particularly fascinating due to their ability to confer drug resistance, which subsequently leads to the failure of therapeutic interventions and hinders successful treatments. One key mechanism by which multidrug resistance (MDR) proteins carry out their transport function is through alternating access. This mechanism involves intricate conformational changes that enable the binding and transport of substrates across cellular membranes. In this extensive review, we provide an overview of ABC transporters, including their classifications and structural similarities. We focus specifically on well-known mammalian multidrug resistance proteins such as MRP1 and Pgp (MDR1), as well as bacterial counterparts such as Sav1866 and lipid flippase MsbA. By exploring the structural and functional features of these MDR proteins, we shed light on the roles of their nucleotide-binding domains (NBDs) and transmembrane domains (TMDs) in the transport process. Notably, while the structures of NBDs in prokaryotic ABC proteins, such as Sav1866, MsbA, and mammalian Pgp, are identical, MRP1 exhibits distinct characteristics in its NBDs. Our review also emphasizes the importance of two ATP molecules for the formation of an interface between the two binding sites of NBD domains across all these transporters. ATP hydrolysis occurs following substrate transport and is vital for recycling the transporters in subsequent cycles of substrate transportation. Specifically, among the studied transporters, only NBD2 in MRP1 possesses the ability to hydrolyze ATP, while both NBDs of Pgp, Sav1866, and MsbA are capable of carrying out this reaction. Furthermore, we highlight recent advancements in the study of MDR proteins and the alternating access mechanism. We discuss the experimental and computational approaches utilized to investigate the structure and dynamics of MDR proteins, providing valuable insights into their conformational changes and substrate transport. This review not only contributes to an enhanced understanding of multidrug resistance proteins but also holds immense potential for guiding future research and facilitating the development of effective strategies to overcome multidrug resistance, thus improving therapeutic interventions.
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Affiliation(s)
- Shadi A Badiee
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, USA
| | - Ugochi H Isu
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, USA
| | - Ehsaneh Khodadadi
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, USA
| | - Mahmoud Moradi
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, USA
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15
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Bina XR, Bina JE. Vibrio cholerae RND efflux systems: mediators of stress responses, colonization and pathogenesis. Front Cell Infect Microbiol 2023; 13:1203487. [PMID: 37256112 PMCID: PMC10225521 DOI: 10.3389/fcimb.2023.1203487] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 04/25/2023] [Indexed: 06/01/2023] Open
Abstract
Resistance Nodulation Division (RND) efflux systems are ubiquitous transporters in gram-negative bacteria that provide protection against antimicrobial agents and thereby enhance survival in virtually all environments these prokaryotes inhabit. Vibrio cholerae is a dual lifestyle enteric pathogen that spends much of its existence in aquatic environments. An unwitting encounter with a human host can lead to V. cholerae intestinal colonization by strains that encode cholera toxin and toxin co-regulated pilus virulence factors leading to potentially fatal cholera diarrhea and dissemination in the environment. Adaptive response mechanisms to host factors encountered by these pathogens are therefore critical both to engage survival mechanisms such as RND-mediated transporters and to induce timely expression of virulence factors. Sensing of cues encountered in the host may therefore activate more than protective responses such as efflux systems, but also be coordinated to initiate expression of virulence factors. This review summarizes recent advances that contribute towards the understanding of RND efflux physiological functions and how the transport systems interface with the regulation of virulence factor production in V. cholerae.
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Affiliation(s)
| | - James E. Bina
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
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16
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Ikujuni AP, Budiardjo SJ, Dhar R, Slusky JSG. Detergent headgroups control TolC folding in vitro. Biophys J 2023; 122:1185-1197. [PMID: 36772796 PMCID: PMC10111266 DOI: 10.1016/j.bpj.2023.02.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Revised: 12/29/2022] [Accepted: 02/07/2023] [Indexed: 02/11/2023] Open
Abstract
TolC is the trimeric outer membrane component of the efflux pump system in Escherichia coli that is responsible for antibiotic efflux from bacterial cells. Overexpression of efflux pumps has been reported to decrease susceptibility to antibiotics in a variety of bacterial pathogens. Reliable production of membrane proteins allows for the biophysical and structural characterization needed to better understand efflux and for the development of therapeutics. Preparation of recombinant protein for biochemical/structural studies often involves the production of proteins as inclusion body aggregates from which active proteins are recovered. Here, we find that the in vitro folding of TolC into its functional trimeric state from inclusion bodies is dependent on the headgroup composition of detergent micelles used. Nonionic detergent favors the formation of functional trimeric TolC, whereas zwitterionic detergents induce the formation of a non-native, oligomeric TolC fold. We also find that nonionic detergents with shorter alkyl lengths facilitate TolC folding. It remains to be seen whether the charges in lipid headgroups have similar effects on membrane insertion and folding in biological systems.
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Affiliation(s)
| | - S Jimmy Budiardjo
- Center for Computational Biology, The University of Kansas, Lawrence, Kansas
| | - Rik Dhar
- Department of Molecular Biosciences, The University of Kansas, Lawrence, Kansas
| | - Joanna S G Slusky
- Department of Molecular Biosciences, The University of Kansas, Lawrence, Kansas; Center for Computational Biology, The University of Kansas, Lawrence, Kansas.
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17
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Guo T, Chen Y, Chen W, Semple SJ, Gu X, Polyak SW, Sun G, Venter H, Ma S. Design and synthesis of benzochromene derivatives as AcrB inhibitors for the reversal of bacterial multidrug resistance. Eur J Med Chem 2023; 249:115148. [PMID: 36709649 DOI: 10.1016/j.ejmech.2023.115148] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 01/17/2023] [Accepted: 01/22/2023] [Indexed: 01/26/2023]
Abstract
A series of novel benzo[h]chromene compounds were designed, synthesized and evaluated for their biological activity as AcrB inhibitors. The compounds were assessed for their ability to potentiate the effect of antibiotics. Compounds with antibiotic-potentiating effects were then evaluated for inhibition of Nile Red efflux, and for off-target effects including activity on the outer and inner bacterial membranes and toxicity. Six compounds were identified to reduce the MIC values of at least one of the tested antibiotics by at least 4-fold, and further reduced the MICs in the presence of a membrane permeabilizer. The identified compounds were also able to inhibit Nile Red efflux at concentrations between 50 μM and 200 μM. The compounds did not disrupt the bacterial outer membrane nor display toxicity in a nematode model (Caenorhabditis elegans). The 4-methoxyphenoxy)propoxy derivative compound G6 possessed the most potent antibacterial potentiation with erythromycin by 8-fold even without the presence of a membrane permeabilizer. Furthermore, H6, G6, G10 and G11 completely abolished the Nile Red efflux at a concentration of 50 μM. The 3,4-dihydro-2H-benzo[h]chromen-5-yl)(morpholino)methanone core appears to be a promising chemical skeleton to be further studied in the discovery of more putative AcrB inhibitors.
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Affiliation(s)
- Ting Guo
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Wenhua Road, Jinan, 250012, China
| | - Yang Chen
- Health and Biomedical Innovation, Clinical and Health Sciences, University of South Australia, Adelaide, SA, 5000, Australia
| | - Weijin Chen
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Wenhua Road, Jinan, 250012, China
| | - Susan J Semple
- Quality Use of Medicines and Pharmacy Research Centre, Clinical and Health Sciences, University of South Australia, Adelaide, SA, 5000, Australia
| | - Xiaotong Gu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Wenhua Road, Jinan, 250012, China
| | - Steven W Polyak
- Health and Biomedical Innovation, Clinical and Health Sciences, University of South Australia, Adelaide, SA, 5000, Australia
| | - Guanglin Sun
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Wenhua Road, Jinan, 250012, China
| | - Henrietta Venter
- Health and Biomedical Innovation, Clinical and Health 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, Cheeloo College of Medicine, Shandong University, 44 West Wenhua Road, Jinan, 250012, China.
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18
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Li T, Wang Z, Guo J, de la Fuente-Nunez C, Wang J, Han B, Tao H, Liu J, Wang X. Bacterial resistance to antibacterial agents: Mechanisms, control strategies, and implications for global health. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 860:160461. [PMID: 36435256 DOI: 10.1016/j.scitotenv.2022.160461] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 11/19/2022] [Accepted: 11/20/2022] [Indexed: 06/16/2023]
Abstract
The spread of bacterial drug resistance has posed a severe threat to public health globally. Here, we cover bacterial resistance to current antibacterial drugs, including traditional herbal medicines, conventional antibiotics, and antimicrobial peptides. We summarize the influence of bacterial drug resistance on global health and its economic burden while highlighting the resistance mechanisms developed by bacteria. Based on the One Health concept, we propose 4A strategies to combat bacterial resistance, including prudent Application of antibacterial agents, Administration, Assays, and Alternatives to antibiotics. Finally, we identify several opportunities and unsolved questions warranting future exploration for combating bacterial resistance, such as predicting genetic bacterial resistance through the use of more effective techniques, surveying both genetic determinants of bacterial resistance and the transmission dynamics of antibiotic resistance genes (ARGs).
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Affiliation(s)
- Ting Li
- Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Beijing 100081, PR China; State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Biotechnology, No. 20, Dongda Street, Fengtai District, Beijing 100071, PR China
| | - Zhenlong Wang
- Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Beijing 100081, PR China
| | - Jianhua Guo
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St Lucia, Queensland 4072, Australia.
| | - Cesar de la Fuente-Nunez
- Machine Biology Group, Departments of Psychiatry and Microbiology, Institute for Biomedical Informatics, Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America; Departments of Bioengineering and Chemical and Biomolecular Engineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States of America; Penn Institute for Computational Science, University of Pennsylvania, Philadelphia, PA, United States of America.
| | - Jinquan Wang
- Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Beijing 100081, PR China
| | - Bing Han
- Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Beijing 100081, PR China
| | - Hui Tao
- Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Beijing 100081, PR China
| | - Jie Liu
- Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Beijing 100081, PR China
| | - Xiumin Wang
- Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Beijing 100081, PR China.
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19
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Wen S, Yin F, Liu C, Dang Y, Sun D, Li P. Integrated analysis of transcriptomic and protein-protein interaction data reveals cadmium stress response in Geobacter sulfurreducens. ENVIRONMENTAL RESEARCH 2023; 218:115063. [PMID: 36528045 DOI: 10.1016/j.envres.2022.115063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Revised: 11/25/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
Bacteria have evolved several mechanisms to resist Cd toxicity, which are crucial for Cd detoxication and have the potential to be used for bioremediation of Cd. Geobacter species are widely found in anaerobic environments and play important roles in natural biogeochemical cycles. However, the transcriptomic response of Geobacter sulfurreducens under Cd stress have not been fully elucidated. Through integrated analysis of transcriptomic and protein-protein interaction (PPI) data, we uncovered a global view of mRNA changes in Cd-induced cellular processes in this study. We identified 182 differentially expressed genes (|log2(fold change)| > 1, adjusted P < 0.05) in G. sulfurreducens exposed to 0.1 mM CdCl2 using RNA sequencing (RNA-seq). Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses showed that CdCl2 significantly affected sulfur compound metabolic processes. In addition, through PPI network analysis, hub genes related to molecular chaperones were identified to play important role in Cd stress response. We also identified a Cd-responsive transcriptional regulator ArsR2 (coded by GSU2149) and verified the function of ArsR2-ParsR2 regulatory circuit in Escherichia coli. This study provides new insight into Cd stress response in G. sulfurreducens, and identified a potential sensor element for Cd detection.
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Affiliation(s)
- Su Wen
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Fei Yin
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Chunmao Liu
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Yan Dang
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Dezhi Sun
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Pengsong Li
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China.
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20
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Gains AF, Lambert DW, Stafford GP. Identification of a Czc-like operon of the periodontal pathobiont P. gingivalis involved in metal ion efflux. Anaerobe 2023; 80:102696. [PMID: 36642290 DOI: 10.1016/j.anaerobe.2023.102696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 01/06/2023] [Accepted: 01/09/2023] [Indexed: 01/15/2023]
Abstract
OBJECTIVE The study aimed to investigate the role of the PGN2012 gene of the periodontitis contributing pathobiont Porphyromonas gingivalis. PGN2012 is a homolgue of TolC and is a gene our group previously showed was overexpressed in hyperinvasive cells. METHODS The study used a combination of bioinformatics, knockout mutagenesis, growth experiments, biofilm assays and human cell invation assays to investigate PGN2012 function. RESULTS Bioinformatics identified that PGN2012 is part of one of four TolC containing gene loci in P. gingivalis that we predicted may encode a metal resistance RND family tripartite pump, similar to those present in other Gram-negative bacteria, but which are not well understood in anaerobic bacteria. A ΔPGN2012 deletion displayed slightly reduced growth in liquid culture but did not effect biofilm formation or human cell invasion. When metal ions were included in the medium the mutant displayed significantly increased sensitivity to the divalent metal ions Zn2+ (500 μM), Co2+ (2 mM), and Cd2+(0.1 mM) but not Cu2+. CONCLUSIONS We propose to rename the PGN2012-2014 genes czcCBA, which we suggest plays a role in intracellular stress resistance where zinc is often employed by host cells in antibacterial defence with implications for chronic infection in humans.
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Affiliation(s)
- A F Gains
- School of Clinical Dentistry, University of Sheffield, Sheffield, S10 2TA, UK
| | - D W Lambert
- School of Clinical Dentistry, University of Sheffield, Sheffield, S10 2TA, UK
| | - G P Stafford
- School of Clinical Dentistry, University of Sheffield, Sheffield, S10 2TA, UK.
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21
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Rouchidane Eyitayo A, Giraud MF, Daury L, Lambert O, Gonzalez C, Manon S. Cell-free synthesis and reconstitution of Bax in nanodiscs: Comparison between wild-type Bax and a constitutively active mutant. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2023; 1865:184075. [PMID: 36273540 DOI: 10.1016/j.bbamem.2022.184075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 10/11/2022] [Accepted: 10/16/2022] [Indexed: 11/06/2022]
Abstract
Bax is a major player in the mitochondrial pathway of apoptosis, by making the Outer Mitochondrial Membrane (OMM) permeable to various apoptogenic factors, including cytochrome c. In order to get further insight into the structure and function of Bax when it is inserted in the OMM, we attempted to reconstitute Bax in nanodiscs. Cell-free protein synthesis in the presence of nanodiscs did not yield Bax-containing nanodiscs, but it provided a simple way to purify full-length Bax without any tag. Purified wild-type Bax (BaxWT) and a constitutively active mutant (BaxP168A) displayed biochemical properties that were in line with previous characterizations following their expression in yeast and human cells followed by their reconstitution into liposomes. Both Bax variants were then reconstituted in nanodiscs. Size exclusion chromatography, dynamic light scattering and transmission electron microscopy showed that nanodiscs formed with BaxP168A were larger than nanodiscs formed with BaxWT. This was consistent with the hypothesis that BaxP168A was reconstituted in nanodiscs as an active oligomer.
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Affiliation(s)
| | - Marie-France Giraud
- IBGC, UMR5095, CNRS, Université de Bordeaux, France; CBMN, UMR5248, CNRS, Université de Bordeaux, France
| | | | | | | | - Stéphen Manon
- IBGC, UMR5095, CNRS, Université de Bordeaux, France.
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22
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Chetri S. The culmination of multidrug-resistant efflux pumps vs. meager antibiotic arsenal era: Urgent need for an improved new generation of EPIs. Front Microbiol 2023; 14:1149418. [PMID: 37138605 PMCID: PMC10149990 DOI: 10.3389/fmicb.2023.1149418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Accepted: 03/13/2023] [Indexed: 05/05/2023] Open
Abstract
Efflux pumps function as an advanced defense system against antimicrobials by reducing the concentration of drugs inside the bacteria and extruding the substances outside. Various extraneous substances, including antimicrobials, toxic heavy metals, dyes, and detergents, have been removed by this protective barrier composed of diverse transporter proteins found in between the cell membrane and the periplasm within the bacterial cell. In this review, multiple efflux pump families have been analytically and widely outlined, and their potential applications have been discussed in detail. Additionally, this review also discusses a variety of biological functions of efflux pumps, including their role in the formation of biofilms, quorum sensing, their survivability, and the virulence in bacteria, and the genes/proteins associated with efflux pumps have also been explored for their potential relevance to antimicrobial resistance and antibiotic residue detection. A final discussion centers around efflux pump inhibitors, particularly those derived from plants.
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23
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Role of Efflux Pumps on Antimicrobial Resistance in Pseudomonas aeruginosa. Int J Mol Sci 2022; 23:ijms232415779. [PMID: 36555423 PMCID: PMC9779380 DOI: 10.3390/ijms232415779] [Citation(s) in RCA: 52] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 12/02/2022] [Accepted: 12/05/2022] [Indexed: 12/15/2022] Open
Abstract
Antimicrobial resistance is an old and silent pandemic. Resistant organisms emerge in parallel with new antibiotics, leading to a major global public health crisis over time. Antibiotic resistance may be due to different mechanisms and against different classes of drugs. These mechanisms are usually found in the same organism, giving rise to multidrug-resistant (MDR) and extensively drug-resistant (XDR) bacteria. One resistance mechanism that is closely associated with the emergence of MDR and XDR bacteria is the efflux of drugs since the same pump can transport different classes of drugs. In Gram-negative bacteria, efflux pumps are present in two configurations: a transmembrane protein anchored in the inner membrane and a complex formed by three proteins. The tripartite complex has a transmembrane protein present in the inner membrane, a periplasmic protein, and a porin associated with the outer membrane. In Pseudomonas aeruginosa, one of the main pathogens associated with respiratory tract infections, four main sets of efflux pumps have been associated with antibiotic resistance: MexAB-OprM, MexXY, MexCD-OprJ, and MexEF-OprN. In this review, the function, structure, and regulation of these efflux pumps in P. aeruginosa and their actions as resistance mechanisms are discussed. Finally, a brief discussion on the potential of efflux pumps in P. aeruginosa as a target for new drugs is presented.
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Duarte B, Figueiredo A, Ramalhosa P, Canning-Clode J, Caçador I, Fonseca VF. Unravelling the Portuguese Coastal and Transitional Waters' Microbial Resistome as a Biomarker of Differential Anthropogenic Impact. TOXICS 2022; 10:613. [PMID: 36287893 PMCID: PMC9612280 DOI: 10.3390/toxics10100613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 10/10/2022] [Accepted: 10/14/2022] [Indexed: 05/14/2023]
Abstract
Portugal mainland and Atlantic archipelagos (Madeira and Azores) provide a wide array of coastal ecosystems with varying typology and degrees of human pressure, which shape the microbial communities thriving in these habitats, leading to the development of microbial resistance traits. The samples collected on the Portuguese northeast Atlantic coast waters show an unequivocal prevalence of Bacteria over Archaea with a high prevalence of Proteobacteria, Cyanobacteria, Bacteroidetes and Actinobacteria. Several taxa, such as the Vibrio genus, showed significant correlations with anthropogenic pollution. These anthropogenic pressures, along with the differences in species diversity among the surveyed sites, lead to observed differences in the presence and resistance-related sequences' abundance (set of all metal and antibiotic resistant genes and their precursors in pathogenic and non-pathogenic bacteria). Gene ontology terms such as antibiotic resistance, redox regulation and oxidative stress response were prevalent. A higher number of significant correlations were found between the abundance of resistance-related sequences and pollution, inorganic pressures and density of nearby population centres when compared to the number of significant correlations between taxa abundance at different phylogenetic levels and the same environmental traits. This points towards predominance of the environmental conditions over the sequence abundance rather than the taxa abundance. Our data suggest that the whole resistome profile can provide more relevant or integrative answers in terms of anthropogenic disturbance of the environment, either as a whole or grouped in gene ontology groups, appearing as a promising tool for impact assessment studies which, due to the ubiquity of the sequences across microbes, can be surveyed independently of the taxa present in the samples.
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Affiliation(s)
- Bernardo Duarte
- MARE—Marine and Environmental Sciences Centre and ARNET—Aquatic Research Infrastructure Network Associated Laboratory, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisbon, Portugal
- Departamento de Biologia Vegetal, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Andreia Figueiredo
- Departamento de Biologia Vegetal, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
- BioISI—Biosystems and Integrative Sciences Institute, Plant Functional Genomics Group, Departamento de Biologia Vegetal, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Patrício Ramalhosa
- MARE—Marine and Environmental Sciences Centre and ARNET—Aquatic Research Infrastructure Network Associated Laboratory, Agência Regional para o Desenvolvimento da Investigação Tecnologia e Inovação (ARDITI), Edifício Madeira Tecnopolo Piso 0, Caminho da Penteada, 9020-105 Funchal, Portugal
- OOM—Oceanic Observatory of Madeira, Agência Regional para o Desenvolvimento da Investigação Tecnologia e Inovação (ARDITI), Edifício Madeira Tecnopolo Piso 0, Caminho da Penteada, 9020-105 Funchal, Portugal
| | - João Canning-Clode
- MARE—Marine and Environmental Sciences Centre and ARNET—Aquatic Research Infrastructure Network Associated Laboratory, Agência Regional para o Desenvolvimento da Investigação Tecnologia e Inovação (ARDITI), Edifício Madeira Tecnopolo Piso 0, Caminho da Penteada, 9020-105 Funchal, Portugal
- Smithsonian Environmental Research Center, 647 Contees Wharf Road, Edgewater, MD 21037, USA
| | - Isabel Caçador
- MARE—Marine and Environmental Sciences Centre and ARNET—Aquatic Research Infrastructure Network Associated Laboratory, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisbon, Portugal
- Departamento de Biologia Vegetal, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Vanessa F. Fonseca
- MARE—Marine and Environmental Sciences Centre and ARNET—Aquatic Research Infrastructure Network Associated Laboratory, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisbon, Portugal
- Departamento de Biologia Animal, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
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25
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Jubair N, R. M, Fatima A, Mahdi YK, Abdullah NH. Evaluation of Catechin Synergistic and Antibacterial Efficacy on Biofilm Formation and acrA Gene Expression of Uropathogenic E. coli Clinical Isolates. Antibiotics (Basel) 2022; 11:antibiotics11091223. [PMID: 36140002 PMCID: PMC9495025 DOI: 10.3390/antibiotics11091223] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/29/2022] [Accepted: 08/29/2022] [Indexed: 11/16/2022] Open
Abstract
Uropathogenic Escherichia coli has a propensity to build biofilms to resist host defense and antimicrobials. Recurrent urinary tract infection (UTI) caused by multidrug-resistant, biofilm-forming E. coli is a significant public health problem. Consequently, searching for alternative medications has become essential. This study was undertaken to investigate the antibacterial, synergistic, and antibiofilm activities of catechin isolated from Canarium patentinervium Miq. against three E. coli ATCC reference strains (ATCC 25922, ATCC 8739, and ATCC 43895) and fifteen clinical isolates collected from UTI patients in Baghdad, Iraq. In addition, the expression of the biofilm-related gene, acrA, was evaluated with and without catechin treatment. Molecular docking was performed to evaluate the binding mode between catechin and the target protein using Autodock Vina 1.2.0 software. Catechin demonstrated significant bactericidal activity with a minimum inhibitory concentration (MIC) range of 1–2 mg/mL and a minimum bactericidal concentration (MBC) range of 2–4 mg/mL and strong synergy when combined with tetracycline at the MBC value. In addition, catechin substantially reduced E. coli biofilm by downregulating the acrA gene with a reduction percent ≥ 60%. In silico analysis revealed that catechin bound with high affinity (∆G = −8.2 kcal/mol) to AcrB protein (PDB-ID: 5ENT), one of the key AcrAB-TolC efflux pump proteins suggesting that catechin might inhibit the acrA gene indirectly by docking at the active site of AcrB protein.
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Affiliation(s)
- Najwan Jubair
- Faculty of Pharmaceutical Sciences, UCSI University, Kuala Lumpur 56000, Malaysia
- Correspondence: (N.J.); (M.R.)
| | - Mogana R.
- Faculty of Pharmaceutical Sciences, UCSI University, Kuala Lumpur 56000, Malaysia
- Correspondence: (N.J.); (M.R.)
| | - Ayesha Fatima
- Beykoz Institute of Life Sciences and Biotechnology, Bezmialem Vakif University, 34820 Istanbul, Turkey
| | - Yasir K. Mahdi
- Faculty of Pharmaceutical Sciences, UCSI University, Kuala Lumpur 56000, Malaysia
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26
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Madrigal P, Singh NK, Wood JM, Gaudioso E, Hernández-Del-Olmo F, Mason CE, Venkateswaran K, Beheshti A. Machine learning algorithm to characterize antimicrobial resistance associated with the International Space Station surface microbiome. MICROBIOME 2022; 10:134. [PMID: 35999570 PMCID: PMC9400218 DOI: 10.1186/s40168-022-01332-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 07/22/2022] [Indexed: 05/07/2023]
Abstract
BACKGROUND Antimicrobial resistance (AMR) has a detrimental impact on human health on Earth and it is equally concerning in other environments such as space habitat due to microgravity, radiation and confinement, especially for long-distance space travel. The International Space Station (ISS) is ideal for investigating microbial diversity and virulence associated with spaceflight. The shotgun metagenomics data of the ISS generated during the Microbial Tracking-1 (MT-1) project and resulting metagenome-assembled genomes (MAGs) across three flights in eight different locations during 12 months were used in this study. The objective of this study was to identify the AMR genes associated with whole genomes of 226 cultivable strains, 21 shotgun metagenome sequences, and 24 MAGs retrieved from the ISS environmental samples that were treated with propidium monoazide (PMA; viable microbes). RESULTS We have analyzed the data using a deep learning model, allowing us to go beyond traditional cut-offs based only on high DNA sequence similarity and extending the catalog of AMR genes. Our results in PMA treated samples revealed AMR dominance in the last flight for Kalamiella piersonii, a bacteria related to urinary tract infection in humans. The analysis of 226 pure strains isolated from the MT-1 project revealed hundreds of antibiotic resistance genes from many isolates, including two top-ranking species that corresponded to strains of Enterobacter bugandensis and Bacillus cereus. Computational predictions were experimentally validated by antibiotic resistance profiles in these two species, showing a high degree of concordance. Specifically, disc assay data confirmed the high resistance of these two pathogens to various beta-lactam antibiotics. CONCLUSION Overall, our computational predictions and validation analyses demonstrate the advantages of machine learning to uncover concealed AMR determinants in metagenomics datasets, expanding the understanding of the ISS environmental microbiomes and their pathogenic potential in humans. Video Abstract.
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Affiliation(s)
- Pedro Madrigal
- Jeffrey Cheah Biomedical Centre, Wellcome-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge Biomedical Campus, Puddicombe Way, Cambridge, CB2 0AW, UK.
- Present Address: European Molecular Biology Laboratory, European Bioinformatics Institute, EMBL-EBI, Hinxton, CB10 1SD, UK.
| | - Nitin K Singh
- Biotechnology and Planetary Protection Group, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, 91109, USA
| | - Jason M Wood
- Biotechnology and Planetary Protection Group, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, 91109, USA
| | - Elena Gaudioso
- Department of Artificial Intelligence, Computer Science School, Universidad Nacional de Educación a Distancia (UNED), 28040, Madrid, Spain
| | - Félix Hernández-Del-Olmo
- Department of Artificial Intelligence, Computer Science School, Universidad Nacional de Educación a Distancia (UNED), 28040, Madrid, Spain
| | - Christopher E Mason
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, 10065, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, 10065, USA
- The WorldQuant Initiative for Quantitative Prediction, Weill Cornell Medicine, New York, NY, 10065, USA
- The Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Kasthuri Venkateswaran
- Biotechnology and Planetary Protection Group, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, 91109, USA
| | - Afshin Beheshti
- KBR, Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, 94035, USA
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
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27
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Evaluation of a Conformationally Constrained Indole Carboxamide as a Potential Efflux Pump Inhibitor in Pseudomonas aeruginosa. Antibiotics (Basel) 2022; 11:antibiotics11060716. [PMID: 35740123 PMCID: PMC9220351 DOI: 10.3390/antibiotics11060716] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 05/16/2022] [Accepted: 05/23/2022] [Indexed: 11/17/2022] Open
Abstract
Efflux pumps in Gram-negative bacteria such as Pseudomonas aeruginosa provide intrinsic antimicrobial resistance by facilitating the extrusion of a wide range of antimicrobials. Approaches for combating efflux-mediated multidrug resistance involve, in part, developing indirect antimicrobial agents capable of inhibiting efflux, thus rescuing the activity of antimicrobials previously rendered inactive by efflux. Herein, TXA09155 is presented as a novel efflux pump inhibitor (EPI) formed by conformationally constraining our previously reported EPI TXA01182. TXA09155 demonstrates strong potentiation in combination with multiple antibiotics with efflux liabilities against wild-type and multidrug-resistant (MDR) P. aeruginosa. At 6.25 µg/mL, TXA09155, showed ≥8-fold potentiation of levofloxacin, moxifloxacin, doxycycline, minocycline, cefpirome, chloramphenicol, and cotrimoxazole. Several biophysical and genetic studies rule out membrane disruption and support efflux inhibition as the mechanism of action (MOA) of TXA09155. TXA09155 was determined to lower the frequency of resistance (FoR) to levofloxacin and enhance the killing kinetics of moxifloxacin. Most importantly, TXA09155 outperformed the levofloxacin-potentiation activity of EPIs TXA01182 and MC-04,124 against a CDC/FDA panel of MDR clinical isolates of P. aeruginosa. TXA09155 possesses favorable physiochemical and ADME properties that warrant its optimization and further development.
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28
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Yang R, Zhang B, Xu Y, Zhang G, Liu Y, Zhang D, Zhang W, Chen T, Liu G. Genomic insights revealed the environmental adaptability of Planococcus halotolerans Y50 isolated from petroleum-contaminated soil on the Qinghai-Tibet Plateau. Gene 2022; 823:146368. [PMID: 35240255 DOI: 10.1016/j.gene.2022.146368] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 02/17/2022] [Accepted: 02/18/2022] [Indexed: 11/28/2022]
Abstract
The Tibetan Plateau niche provides unprecedented opportunities to find microbes that are functional and commercial significance. The present study investigated the physiological and genomic characteristics of Planococcus halotolerans Y50 that was isolated from a petroleum-contaminated soil sample from the Qinghai-Tibet Plateau, and it displayed psychrotolerant, antiradiation, and oil-degraded characteristics. Whole genome sequencing indicated that strain Y50 has a 3.52 Mb genome and 44.7% G + C content, and it possesses 3377 CDSs. The presence of a wide range of UV damage repair genes uvrX and uvsE, DNA repair genes radA and recN, superoxide dismutase, peroxiredoxin and dioxygenase genes provided the genomic basis for the adaptation of the plateau environment polluted by petroleum. Related experiments also verified that the Y50 strain could degrade n-alkanes from C11-C23, and approximately 30% of the total petroleum at 25 °C within 7 days. Meanwhile, strain Y50 could withstand 5 × 103 J/m2 UVC and 10 KGy gamma ray radiation, and it had strong antioxidant and high radical scavengers for superoxide anion, hydroxyl radical and DPPH. In addition, pan-genome analysis and horizontal gene transfers revealed that strains with different niches have obtained various genes through horizontal gene transfer in the process of evolution, and the more similar their geographical locations, the more similar their members are genetically and ecologically. In conclusion, P. halotolerans Y50 possesses high potential of applications in the bioremediation of alpine hydrocarbons contaminated environment.
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Affiliation(s)
- Ruiqi Yang
- College of Urban Environment, Lanzhou City University, Lanzhou 730070, China; Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Gansu Province, 730000, China
| | - Binglin Zhang
- State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy Sciences, Lanzhou 730000, China; Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Gansu Province, 730000, China.
| | - Yeteng Xu
- State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy Sciences, Lanzhou 730000, China; Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Gansu Province, 730000, China
| | - Gaosen Zhang
- Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Gansu Province, 730000, China; Key Laboratory of Desert and Desertification, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Yang Liu
- Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Gansu Province, 730000, China; Key Laboratory of Desert and Desertification, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Dongming Zhang
- School of Engineering Sciences in Chemistry, Biotechnology, and Health (CBH), KTH Royal Institute of Technology, Stockholm, Sweden
| | - Wei Zhang
- Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Gansu Province, 730000, China; Key Laboratory of Desert and Desertification, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Tuo Chen
- State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy Sciences, Lanzhou 730000, China; Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Gansu Province, 730000, China
| | - Guangxiu Liu
- Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Gansu Province, 730000, China; Key Laboratory of Desert and Desertification, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
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29
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Huang L, Wu C, Gao H, Xu C, Dai M, Huang L, Hao H, Wang X, Cheng G. Bacterial Multidrug Efflux Pumps at the Frontline of Antimicrobial Resistance: An Overview. Antibiotics (Basel) 2022; 11:antibiotics11040520. [PMID: 35453271 PMCID: PMC9032748 DOI: 10.3390/antibiotics11040520] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 04/01/2022] [Accepted: 04/08/2022] [Indexed: 02/06/2023] Open
Abstract
Multidrug efflux pumps function at the frontline to protect bacteria against antimicrobials by decreasing the intracellular concentration of drugs. This protective barrier consists of a series of transporter proteins, which are located in the bacterial cell membrane and periplasm and remove diverse extraneous substrates, including antimicrobials, organic solvents, toxic heavy metals, etc., from bacterial cells. This review systematically and comprehensively summarizes the functions of multiple efflux pumps families and discusses their potential applications. The biological functions of efflux pumps including their promotion of multidrug resistance, biofilm formation, quorum sensing, and survival and pathogenicity of bacteria are elucidated. The potential applications of efflux pump-related genes/proteins for the detection of antibiotic residues and antimicrobial resistance are also analyzed. Last but not least, efflux pump inhibitors, especially those of plant origin, are discussed.
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30
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González D, Robas M, Fernández V, Bárcena M, Probanza A, Jiménez PA. Comparative Metagenomic Study of Rhizospheric and Bulk Mercury-Contaminated Soils in the Mining District of Almadén. Front Microbiol 2022; 13:797444. [PMID: 35330761 PMCID: PMC8940170 DOI: 10.3389/fmicb.2022.797444] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 01/17/2022] [Indexed: 12/22/2022] Open
Abstract
Soil contamination by heavy metals, particularly mercury (Hg), is a problem that can seriously affect the environment, animals, and human health. Hg has the capacity to biomagnify in the food chain. That fact can lead to pathologies, of those which affect the central nervous system being the most severe. It is convenient to know the biological environmental indicators that alert of the effects of Hg contamination as well as the biological mechanisms that can help in its remediation. To contribute to this knowledge, this study conducted comparative analysis by the use of Shotgun metagenomics of the microbial communities in rhizospheric soils and bulk soil of the mining region of Almadén (Ciudad Real, Spain), one of the most affected areas by Hg in the world The sequences obtained was analyzed with MetaPhlAn2 tool and SUPER-FOCUS. The most abundant taxa in the taxonomic analysis in bulk soil were those of Actinobateria and Alphaproteobacteria. On the contrary, in the rhizospheric soil microorganisms belonging to the phylum Proteobacteria were abundant, evidencing that roots have a selective effect on the rhizospheric communities. In order to analyze possible indicators of biological contamination, a functional potential analysis was performed. The results point to a co-selection of the mechanisms of resistance to Hg and the mechanisms of resistance to antibiotics or other toxic compounds in environments contaminated by Hg. Likewise, the finding of antibiotic resistance mechanisms typical of the human clinic, such as resistance to beta-lactams and glycopeptics (vancomycin), suggests that these environments can behave as reservoirs. The sequences involved in Hg resistance (operon mer and efflux pumps) have a similar abundance in both soil types. However, the response to abiotic stress (salinity, desiccation, and contaminants) is more prevalent in rhizospheric soil. Finally, sequences involved in nitrogen fixation and metabolism and plant growth promotion (PGP genes) were identified, with higher relative abundances in rhizospheric soils. These findings can be the starting point for the targeted search for microorganisms suitable for further use in bioremediation processes in Hg-contaminated environments.
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Affiliation(s)
- Daniel González
- Department of Pharmaceutical Science and Health, CEU Universities, Boadilla del Monte, Spain
| | - Marina Robas
- Department of Pharmaceutical Science and Health, CEU Universities, Boadilla del Monte, Spain
| | - Vanesa Fernández
- Department of Pharmaceutical Science and Health, CEU Universities, Boadilla del Monte, Spain
| | - Marta Bárcena
- Department of Pharmaceutical Science and Health, CEU Universities, Boadilla del Monte, Spain
| | - Agustín Probanza
- Department of Pharmaceutical Science and Health, CEU Universities, Boadilla del Monte, Spain
| | - Pedro A Jiménez
- Department of Pharmaceutical Science and Health, CEU Universities, Boadilla del Monte, Spain
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31
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A role for the periplasmic adaptor protein AcrA in vetting substrate access to the RND efflux transporter AcrB. Sci Rep 2022; 12:4752. [PMID: 35306531 PMCID: PMC8934357 DOI: 10.1038/s41598-022-08903-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 03/14/2022] [Indexed: 11/08/2022] Open
Abstract
Tripartite resistance-nodulation-division (RND) efflux pumps, such as AcrAB-TolC of Salmonella Typhimurium, contribute to antibiotic resistance and comprise an inner membrane RND-transporter, an outer membrane factor, and a periplasmic adaptor protein (PAP). The role of the PAP in the assembly and active transport process remains poorly understood. Here, we identify the functionally critical residues involved in PAP-RND-transporter binding between AcrA and AcrB and show that the corresponding RND-binding residues in the closely related PAP AcrE, are also important for its interaction with AcrB. We also report a residue in the membrane-proximal domain of AcrA, that when mutated, differentially affects the transport of substrates utilising different AcrB efflux channels, namely channels 1 and 2. This supports a potential role for the PAP in sensing the substrate-occupied state of the proximal binding pocket of the transporter and substrate vetting. Understanding the PAP’s role 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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32
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Advances in Key Drug Target Identification and New Drug Development for Tuberculosis. BIOMED RESEARCH INTERNATIONAL 2022; 2022:5099312. [PMID: 35252448 PMCID: PMC8896939 DOI: 10.1155/2022/5099312] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Accepted: 02/14/2022] [Indexed: 12/15/2022]
Abstract
Tuberculosis (TB) is a severe infectious disease worldwide. The increasing emergence of drug-resistant Mycobacterium tuberculosis (Mtb) has markedly hampered TB control. Therefore, there is an urgent need to develop new anti-TB drugs to treat drug-resistant TB and shorten the standard therapy. The discovery of targets of drug action will lay a theoretical foundation for new drug development. With the development of molecular biology and the success of Mtb genome sequencing, great progress has been made in the discovery of new targets and their relevant inhibitors. In this review, we summarized 45 important drug targets and 15 new drugs that are currently being tested in clinical stages and several prospective molecules that are still at the level of preclinical studies. A comprehensive understanding of the drug targets of Mtb can provide extensive insights into the development of safer and more efficient drugs and may contribute new ideas for TB control and treatment.
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Budiardjo SJ, Stevens JJ, Calkins AL, Ikujuni AP, Wimalasena VK, Firlar E, Case DA, Biteen JS, Kaelber JT, Slusky JSG. Colicin E1 opens its hinge to plug TolC. eLife 2022; 11:73297. [PMID: 35199644 PMCID: PMC9020818 DOI: 10.7554/elife.73297] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 02/21/2022] [Indexed: 12/02/2022] Open
Abstract
The double membrane architecture of Gram-negative bacteria forms a barrier that is impermeable to most extracellular threats. Bacteriocin proteins evolved to exploit the accessible, surface-exposed proteins embedded in the outer membrane to deliver cytotoxic cargo. Colicin E1 is a bacteriocin produced by, and lethal to, Escherichia coli that hijacks the outer membrane proteins (OMPs) TolC and BtuB to enter the cell. Here, we capture the colicin E1 translocation domain inside its membrane receptor, TolC, by high-resolution cryo-electron microscopy to obtain the first reported structure of a bacteriocin bound to TolC. Colicin E1 binds stably to TolC as an open hinge through the TolC pore—an architectural rearrangement from colicin E1’s unbound conformation. This binding is stable in live E. coli cells as indicated by single-molecule fluorescence microscopy. Finally, colicin E1 fragments binding to TolC plug the channel, inhibiting its native efflux function as an antibiotic efflux pump, and heightening susceptibility to three antibiotic classes. In addition to demonstrating that these protein fragments are useful starting points for developing novel antibiotic potentiators, this method could be expanded to other colicins to inhibit other OMP functions. Bacteria are constantly warring with each other for space and resources. As a result, they have developed a range of molecular weapons to poison, damage or disable other cells. For instance, bacteriocins are proteins that can latch onto structures at the surface of enemy bacteria and push toxins through their outer membrane. Bacteria are increasingly resistant to antibiotics, representing a growing concern for modern healthcare. One way that they are able to survive is by using ‘efflux pumps’ studded through their external membranes to expel harmful drugs before these can cause damage. Budiardjo et al. wanted to test whether bacteriocins could interfere with this defence mechanism by blocking efflux pumps. Bacteriocins are usually formed of binding elements (which recognise specific target proteins) and of a ‘killer tail’ that can stab the cell. Experiments showed that the binding parts of a bacteriocin could effectively ‘plug’ efflux pumps in Escherichia coli bacteria: high-resolution molecular microscopy revealed how the bacteriocin fragment binds to the pump, while fluorescent markers showed that it attached to the surface of E. coli and stopped the efflux pumps from working. As a result, lower amounts of antibiotics were necessary to kill the bacteria when bacteriocins were present. The work by Budiardjo et al. could lead to new ways to combat bacteria that will reduce the need for current antibiotics. In the future, bacteriocins could also be harnessed to target other proteins than efflux pumps, allowing scientists to manipulate a range of bacterial processes.
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Affiliation(s)
- S Jimmy Budiardjo
- Center for Computational Biology, University of Kansas, Lawrence, United States
| | - Jacqueline J Stevens
- Department of Molecular Biosciences, University of Kansas, Lawrence, United States
| | - Anna L Calkins
- Department of Chemistry, University of Michigan, Ann Arbor, United States
| | - Ayotunde P Ikujuni
- Department of Molecular Biosciences, University of Kansas, Lawrence, United States
| | | | - Emre Firlar
- Institute for Quantitative Biomedicine, Rutgers University, Piscataway, United States
| | - David A Case
- Institute for Quantitative Biomedicine, Rutgers University, Piscataway, United States
| | - Julie S Biteen
- Department of Chemistry, University of Michigan, Ann Arbor, United States
| | - Jason T Kaelber
- Institute for Quantitative Biomedicine, Rutgers, The State University of New Jersey, Piscataway, United States
| | - Joanna S G Slusky
- Center for Computational Biology, University of Kansas, Lawrence, United States
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Garcia ÍR, de Oliveira Garcia FA, Pereira PS, Coutinho HDM, Siyadatpanah A, Norouzi R, Wilairatana P, de Lourdes Pereira M, Nissapatorn V, Tintino SR, Rodrigues FFG. Microbial resistance: The role of efflux pump superfamilies and their respective substrates. Life Sci 2022; 295:120391. [PMID: 35149116 DOI: 10.1016/j.lfs.2022.120391] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 02/02/2022] [Accepted: 02/06/2022] [Indexed: 12/24/2022]
Abstract
The microorganism resistance to antibiotics has become one of the most worrying issues for science due to the difficulties related to clinical treatment and the rapid spread of diseases. Efflux pumps are classified into six groups of carrier proteins that are part of the different types of mechanisms that contribute to resistance in microorganisms, allowing their survival. The present study aimed to carry out a bibliographic review on the superfamilies of carriers in order to understand their compositions, expressions, substrates, and role in intrinsic resistance. At first, a search for manuscripts was carried out in the databases Medline, Pubmed, ScienceDirect, and Scielo, using as descriptors: efflux pump, expression, pump inhibitors and efflux superfamily. For article selection, two criteria were taken into account: for inclusion, those published between 2000 and 2020, including textbooks, and for exclusion, duplicates and academic collections. In this research, 139,615 published articles were obtained, with 312 selected articles and 7 book chapters that best met the aim. From the comprehensive analysis, it was possible to consider that the chromosomes and genetic elements can contain genes encoding efflux pumps and are responsible for multidrug resistance. Even though this is a well-explored topic in the scientific community, understanding the behavior of antibiotics as substrates that increase the expression of pump-encoding genes has challenged medicine. This review study succinctly summarizes the most relevant features of these systems, as well as their contribution to multidrug resistance.
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Affiliation(s)
| | | | | | | | - Abolghasem Siyadatpanah
- Ferdows School of Paramedical and Health, Birjand University of Medical Sciences, Birjand, Iran
| | - Roghayeh Norouzi
- Department of Pathobiology, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran
| | - Polrat Wilairatana
- Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
| | - Maria de Lourdes Pereira
- CICECO-Aveiro Institute of Materials & Department of Medical Sciences, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Veeranoot Nissapatorn
- School of Allied Health Sciences and Research Excellence Center for Innovation and Health, Walailak University, Thailand
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Molecular Determinants for OMF Selectivity in Tripartite RND Multidrug Efflux Systems. Antibiotics (Basel) 2022; 11:antibiotics11020126. [PMID: 35203729 PMCID: PMC8868134 DOI: 10.3390/antibiotics11020126] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 01/13/2022] [Accepted: 01/15/2022] [Indexed: 12/10/2022] Open
Abstract
Tripartite multidrug RND efflux systems made of an inner membrane transporter, an outer membrane factor (OMF) and a periplasmic adaptor protein (PAP) form a canal to expel drugs across Gram-negative cell wall. Structures of MexA–MexB–OprM and AcrA–AcrB–TolC, from Pseudomonas aeruginosa and Escherichia coli, respectively, depict a reduced interfacial contact between OMF and PAP, making unclear the comprehension of how OMF is recruited. Here, we show that a Q93R mutation of MexA located in the α-hairpin domain increases antibiotic resistance in the MexAQ93R–MexB–OprM-expressed strain. Electron microscopy single-particle analysis reveals that this mutation promotes the formation of tripartite complexes with OprM and non-cognate components OprN and TolC. Evidence indicates that MexAQ93R self-assembles into a hexameric form, likely due to interprotomer interactions between paired R93 and D113 amino acids. C-terminal deletion of OprM prevents the formation of tripartite complexes when mixed with MexA and MexB components but not when replacing MexA with MexAQ93R. This study reveals the Q93R MexA mutation and the OprM C-terminal peptide as molecular determinants modulating the assembly process efficacy with cognate and non-cognate OMFs, even though they are outside the interfacial contact. It provides insights into how OMF selectivity operates during the formation of the tripartite complex.
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Cacciotto P, Basciu A, Oliva F, Malloci G, Zacharias M, Ruggerone P, Vargiu AV. Molecular rationale for the impairment of the MexAB-OprM efflux pump by a single mutation in MexA. Comput Struct Biotechnol J 2022; 20:252-260. [PMID: 35024097 PMCID: PMC8717590 DOI: 10.1016/j.csbj.2021.11.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 11/29/2021] [Accepted: 11/30/2021] [Indexed: 11/16/2022] Open
Abstract
Efflux pumps of the Resistance-Nodulation-cell Division (RND) superfamily contribute to intrinsic and acquired resistance in Gram-negative pathogens by expelling chemically unrelated antibiotics with high efficiency. They are tripartite systems constituted by an inner-membrane-anchored transporter, an outer membrane factor protein, and a membrane fusion protein. Multimerization of the membrane fusion protein is an essential prerequisite for full functionality of these efflux pumps. In this work, we employed complementary computational techniques to investigate the stability of a dimeric unit of MexA (the membrane fusion protein of the MexAB-OprM RND efflux pump of Pseudomonas aeruginosa), and to provide a molecular rationale for the effect of the G72S substitution, which affects MexAB-OprM functionality by impairing the assembly of MexA. Our findings indicate that: i) dimers of this protein are stable in multiple µs-long molecular dynamics simulations; ii) the mutation drastically alters the conformational equilibrium of MexA, favouring a collapsed conformation that is unlikely to form dimers or higher order assemblies. Unveiling the mechanistic aspects underlying large conformational distortions induced by minor sequence changes is informative to efforts at interfering with the activity of this elusive bacterial weapon. In this respect, our work further confirms how molecular simulations can give important contribution and useful insights to characterize the mechanism of highly complex biological systems.
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Affiliation(s)
- Pierpaolo Cacciotto
- Dipartimento di Fisica, Università degli Studi di Cagliari, S.P. Monserrato-Sestu km 0.700, I-09042 Monserrato (CA), Italy
| | - Andrea Basciu
- Dipartimento di Fisica, Università degli Studi di Cagliari, S.P. Monserrato-Sestu km 0.700, I-09042 Monserrato (CA), Italy
| | - Francesco Oliva
- Dipartimento di Fisica, Università degli Studi di Cagliari, S.P. Monserrato-Sestu km 0.700, I-09042 Monserrato (CA), Italy
| | - Giuliano Malloci
- Dipartimento di Fisica, Università degli Studi di Cagliari, S.P. Monserrato-Sestu km 0.700, I-09042 Monserrato (CA), Italy
| | - Martin Zacharias
- Physics Department, Technische Universität München, James-Franck-Str. 1, 85748 Garching, Germany
| | - Paolo Ruggerone
- Dipartimento di Fisica, Università degli Studi di Cagliari, S.P. Monserrato-Sestu km 0.700, I-09042 Monserrato (CA), Italy
| | - Attilio V Vargiu
- Dipartimento di Fisica, Università degli Studi di Cagliari, S.P. Monserrato-Sestu km 0.700, I-09042 Monserrato (CA), Italy
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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: 32] [Impact Index Per Article: 16.0] [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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Laborda P, Hernando-Amado S, Martínez JL, Sanz-García F. Antibiotic Resistance in Pseudomonas. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1386:117-143. [DOI: 10.1007/978-3-031-08491-1_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Webber A, Ratnaweera M, Harris A, Luisi BF, Ntsogo Enguéné VY. A Model for Allosteric Communication in Drug Transport by the AcrAB-TolC Tripartite Efflux Pump. Antibiotics (Basel) 2022; 11:52. [PMID: 35052929 PMCID: PMC8773123 DOI: 10.3390/antibiotics11010052] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 12/22/2021] [Accepted: 12/28/2021] [Indexed: 01/30/2023] Open
Abstract
RND family efflux pumps are complex macromolecular machines involved in multidrug resistance by extruding antibiotics from the cell. While structural studies and molecular dynamics simulations have provided insights into the architecture and conformational states of the pumps, the path followed by conformational changes from the inner membrane protein (IMP) to the periplasmic membrane fusion protein (MFP) and to the outer membrane protein (OMP) in tripartite efflux assemblies is not fully understood. Here, we investigated AcrAB-TolC efflux pump's allostery by comparing resting and transport states using difference distance matrices supplemented with evolutionary couplings data and buried surface area measurements. Our analysis indicated that substrate binding by the IMP triggers quaternary level conformational changes in the MFP, which induce OMP to switch from the closed state to the open state, accompanied by a considerable increase in the interface area between the MFP subunits and between the OMPs and MFPs. This suggests that the pump's transport-ready state is at a more favourable energy level than the resting state, but raises the puzzle of how the pump does not become stably trapped in a transport-intermediate state. We propose a model for pump allostery that includes a downhill energetic transition process from a proposed 'activated' transport state back to the resting pump.
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Affiliation(s)
- Anya Webber
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1GA, UK; (A.W.); (A.H.)
| | - Malitha Ratnaweera
- Department of Oncology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK;
| | - Andrzej Harris
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1GA, UK; (A.W.); (A.H.)
| | - Ben F. Luisi
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1GA, UK; (A.W.); (A.H.)
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Evaluation of Heterocyclic Carboxamides as Potential Efflux Pump Inhibitors in Pseudomonas aeruginosa. Antibiotics (Basel) 2021; 11:antibiotics11010030. [PMID: 35052908 PMCID: PMC8772707 DOI: 10.3390/antibiotics11010030] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 12/20/2021] [Accepted: 12/23/2021] [Indexed: 12/19/2022] Open
Abstract
The ability to rescue the activity of antimicrobials that are no longer effective against bacterial pathogens such as Pseudomonas aeruginosa is an attractive strategy to combat antimicrobial drug resistance. Herein, novel efflux pump inhibitors (EPIs) demonstrating strong potentiation in combination with levofloxacin against wild-type P. aeruginosa ATCC 27853 are presented. A structure activity relationship of aryl substituted heterocyclic carboxamides containing a pentane diamine side chain is described. Out of several classes of fused heterocyclic carboxamides, aryl indole carboxamide compound 6j (TXA01182) at 6.25 µg/mL showed 8-fold potentiation of levofloxacin. TXA01182 was found to have equally synergistic activities with other antimicrobial classes (monobactam, fluoroquinolones, sulfonamide and tetracyclines) against P. aeruginosa. Several biophysical and genetic studies rule out membrane disruption and support efflux inhibition as the mechanism of action (MOA) of TXA01182. TXA01182 was determined to lower the frequency of resistance (FoR) of the partner antimicrobials and enhance the killing kinetics of levofloxacin. Furthermore, TXA01182 demonstrated a synergistic effect with levofloxacin against several multidrug resistant P. aeruginosa clinical isolates.
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Koderi Valappil S, Shetty P, Deim Z, Terhes G, Urbán E, Váczi S, Patai R, Polgár T, Pertics BZ, Schneider G, Kovács T, Rákhely G. Survival Comes at a Cost: A Coevolution of Phage and Its Host Leads to Phage Resistance and Antibiotic Sensitivity of Pseudomonas aeruginosa Multidrug Resistant Strains. Front Microbiol 2021; 12:783722. [PMID: 34925289 PMCID: PMC8678094 DOI: 10.3389/fmicb.2021.783722] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Accepted: 11/08/2021] [Indexed: 01/12/2023] Open
Abstract
The increasing ineffectiveness of traditional antibiotics and the rise of multidrug resistant (MDR) bacteria have necessitated the revival of bacteriophage (phage) therapy. However, bacteria might also evolve resistance against phages. Phages and their bacterial hosts coexist in nature, resulting in a continuous coevolutionary competition for survival. We have isolated several clinical strains of Pseudomonas aeruginosa and phages that infect them. Among these, the PIAS (Phage Induced Antibiotic Sensitivity) phage belonging to the Myoviridae family can induce multistep genomic deletion in drug-resistant clinical strains of P. aeruginosa, producing a compromised drug efflux system in the bacterial host. We identified two types of mutant lines in the process: green mutants with SNPs (single nucleotide polymorphisms) and smaller deletions and brown mutants with large (∼250 kbp) genomic deletion. We demonstrated that PIAS used the MexXY-OprM system to initiate the infection. P. aeruginosa clogged PIAS phage infection by either modifying or deleting these receptors. The green mutant gaining phage resistance by SNPs could be overcome by evolved PIASs (E-PIASs) with a mutation in its tail-fiber protein. Characterization of the mutant phages will provide a deeper understanding of phage-host interaction. The coevolutionary process continued with large deletions in the same regions of the bacterial genomes to block the (E-)PIAS infection. These mutants gained phage resistance via either complete loss or substantial modifications of the phage receptor, MexXY-OprM, negating its essential role in antibiotic resistance. In vitro and in vivo studies indicated that combined use of PIAS and antibiotics could effectively inhibit P. aeruginosa growth. The phage can either eradicate bacteria or induce antibiotic sensitivity in MDR-resistant clinical strains. We have explored the potential use of combination therapy as an alternative approach against MDR P. aeruginosa infection.
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Affiliation(s)
| | - Prateek Shetty
- Institute of Plant Biology, Biological Research Center, Szeged, Hungary
- Doctoral School of Biology, University of Szeged, Szeged, Hungary
| | - Zoltán Deim
- Department of Biotechnology, University of Szeged, Szeged, Hungary
| | - Gabriella Terhes
- Department of Clinical Microbiology, University of Szeged, Szeged, Hungary
| | - Edit Urbán
- Department of Clinical Microbiology, University of Szeged, Szeged, Hungary
| | - Sándor Váczi
- Department of Pathophysiology, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Roland Patai
- Institute of Biophysics, Biological Research Center, Szeged, Hungary
| | - Tamás Polgár
- Institute of Biophysics, Biological Research Center, Szeged, Hungary
- Doctoral School of Theoretical Medicine, University of Szeged, Szeged, Hungary
| | | | - György Schneider
- Department of Medical Microbiology and Immunology, University of Pécs, Pécs, Hungary
| | - Tamás Kovács
- Department of Biotechnology, Nanophagetherapy Center, Enviroinvest Corp., Pécs, Hungary
- Biopesticide Ltd., Pécs, Hungary
| | - Gábor Rákhely
- Department of Biotechnology, University of Szeged, Szeged, Hungary
- Institute of Biophysics, Biological Research Center, Szeged, Hungary
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Adrien V, Rayan G, Astafyeva K, Broutin I, Picard M, Fuchs P, Urbach W, Taulier N. How to best estimate the viscosity of lipid bilayers. Biophys Chem 2021; 281:106732. [PMID: 34844029 DOI: 10.1016/j.bpc.2021.106732] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 10/19/2021] [Accepted: 11/19/2021] [Indexed: 11/02/2022]
Abstract
The viscosity of lipid bilayers is a property relevant to biological function, as it affects the diffusion of membrane macromolecules. To determine its value, and hence portray the membrane, various literature-reported techniques lead to significantly different results. Herein we compare the results issuing from two widely used techniques to determine the viscosity of membranes: the Fluorescence Lifetime Imaging Microscopy (FLIM), and Fluorescence Recovery After Photobleaching (FRAP). FLIM relates the time of rotation of a molecular rotor inserted into the membrane to the macroscopic viscosity of a fluid. Whereas FRAP measures molecular diffusion coefficients. This approach is based on a hydrodynamic model connecting the mobility of a membrane inclusion to the viscosity of the membrane. We show that: This article emphasizes the pitfalls to be avoided and the rules to be observed in order to obtain a value of the bilayer viscosity that characterizes the bilayer instead of interactions between the bilayer and the embedded probe.
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Affiliation(s)
- Vladimir Adrien
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France; Université de Paris, CNRS, Laboratoire CiTCoM, 75006 Paris, France; Sorbonne Université, AP-HP Department of Psychiatry, Hôpital Saint-Antoine, Paris, France
| | - Gamal Rayan
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France.
| | - Ksenia Astafyeva
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France
| | - Isabelle Broutin
- Université de Paris, CNRS, Laboratoire CiTCoM, 75006 Paris, France
| | - Martin Picard
- Université de Paris, Laboratoire de Biologie Physico-Chimique des Protéines Membranaires, CNRS UMR 7099, F-75005 Paris, France; Institut de Biologie Physico-Chimique, Fondation Edmond de Rothschild pour le développement de la recherche Scientifique, F-75005 Paris, France
| | - Patrick Fuchs
- Sorbonne Université, Ecole Normale Supérieure, PSL University, CNRS, Laboratoire des Biomolécules (LBM), 75005 Paris, France; Université de Paris, UFR Sciences du Vivant, 75013 Paris, France
| | - Wladimir Urbach
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France; Sorbonne Université, CNRS, INSERM, Laboratoire d'Imagerie Biomédicale, LIB, F-75006 Paris, France
| | - Nicolas Taulier
- Sorbonne Université, CNRS, INSERM, Laboratoire d'Imagerie Biomédicale, LIB, F-75006 Paris, France
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Gumbart JC, Ferreira JL, Hwang H, Hazel AJ, Cooper CJ, Parks JM, Smith JC, Zgurskaya HI, Beeby M. Lpp positions peptidoglycan at the AcrA-TolC interface in the AcrAB-TolC multidrug efflux pump. Biophys J 2021; 120:3973-3982. [PMID: 34411576 DOI: 10.1016/j.bpj.2021.08.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 07/02/2021] [Accepted: 08/11/2021] [Indexed: 01/07/2023] Open
Abstract
The multidrug efflux pumps of Gram-negative bacteria are a class of complexes that span the periplasm, coupling both the inner and outer membranes to expel toxic molecules. The best-characterized example of these tripartite pumps is the AcrAB-TolC complex of Escherichia coli. However, how the complex interacts with the peptidoglycan (PG) cell wall, which is anchored to the outer membrane (OM) by Braun's lipoprotein (Lpp), is still largely unknown. In this work, we present molecular dynamics simulations of a complete, atomistic model of the AcrAB-TolC complex with the inner membrane, OM, and PG layers all present. We find that the PG localizes to the junction of AcrA and TolC, in agreement with recent cryo-tomography data. Free-energy calculations reveal that the positioning of PG is determined by the length and conformation of multiple Lpp copies anchoring it to the OM. The distance between the PG and OM measured in cryo-electron microscopy images of wild-type E. coli also agrees with the simulation-derived spacing. Sequence analysis of AcrA suggests a conserved role for interactions with PG in the assembly and stabilization of efflux pumps, one that may extend to other trans-envelope complexes as well.
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Affiliation(s)
- James C Gumbart
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia.
| | - Josie L Ferreira
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Hyea Hwang
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia
| | - Anthony J Hazel
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia
| | - Connor J Cooper
- UT/ORNL Center for Molecular Biophysics, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee
| | - Jerry M Parks
- UT/ORNL Center for Molecular Biophysics, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee
| | - Jeremy C Smith
- UT/ORNL Center for Molecular Biophysics, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee; Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee
| | - Helen I Zgurskaya
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma
| | - Morgan Beeby
- Department of Life Sciences, Imperial College London, London, United Kingdom
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Khare T, Mahalunkar S, Shriram V, Gosavi S, Kumar V. Embelin-loaded chitosan gold nanoparticles interact synergistically with ciprofloxacin by inhibiting efflux pumps in multidrug-resistant Pseudomonas aeruginosa and Escherichia coli. ENVIRONMENTAL RESEARCH 2021; 199:111321. [PMID: 33989619 DOI: 10.1016/j.envres.2021.111321] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Revised: 04/30/2021] [Accepted: 05/08/2021] [Indexed: 05/20/2023]
Abstract
A global upsurge in emergence and spread of antibiotic resistance (ABR) in bacterial populations is a serious threat for human health. Unfortunately, ABR is no longer confined to nosocomial environments and is frequently reported from community microbes as well. The ABR is resulting in shrinking potent antibiotics pool and thus necessitating novel and alternative therapies and therapeutics. Current investigation was aimed to assess the synergistic potential of a synthesized, phytomolecule-loaded, polysaccharide-stabilized metallic nanoparticles (NPs) against Pseudomonas aeruginosa (PA) and Escherichia coli (EC) isolated from river waters. ABR profiling of these strains characterized them as multidrug resistant (MDR). Synthesized embelin (Emb, isolated from Embelia tsjeriam-cottam)-loaded, chitosan-gold (Emb-Chi-Au) NPs were assessed for their potential synergistic activity with ciprofloxacin (CIP) via checker-board assay and time-kill curve analysis. The NPs reduced the minimal inhibitory concentration (MIC) of CIP by 16- and 4-fold against MDR PA (PA-r) and EC (EC-r) strains, respectively. Fractional inhibitory concentration (FIC) indices with ≤0.5 values confirmed the synergy between the Emb-Chi-Au NPs and CIP, which was further confirmed at ½ MICs in both PA-r and EC-r via time-kill curve analysis. In order to decipher the mode of action, efflux pump inhibitory effects of Emb-Chi-Au NPs were evaluated in terms of the increase in the EtBr mediated fluorescence in control versus NP-treated MDR strains. Molecular docking based in silico simulations were used to predict the interactions between Emb and the active sites of the efflux pump related proteins in PA-r (MexA, MexB and OprM) and EC-r (AcrA, AcrB and TolC), which revealed the probable bond formation between Emb and respective amino acid residues.
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Affiliation(s)
- Tushar Khare
- Department of Biotechnology, Modern College of Arts, Science and Commerce (Savitribai Phule Pune University), Ganeshkhind, Pune, 411016, India; Department of Environmental Science, Savitribai Phule Pune University, Pune, 411007, India
| | - Sneha Mahalunkar
- School of Basic Medical Science, Savitribai Phule Pune University, Pune, 411007, India
| | - Varsha Shriram
- Department of Botany, Prof. Ramkrishna More Arts, Commerce and Science College (Savitribai Phule Pune University), Pune, 411044, India
| | - Suresh Gosavi
- School of Basic Medical Science, Savitribai Phule Pune University, Pune, 411007, India; Department of Physics, Savitribai Phule Pune University, Pune, 411007, India.
| | - Vinay Kumar
- Department of Biotechnology, Modern College of Arts, Science and Commerce (Savitribai Phule Pune University), Ganeshkhind, Pune, 411016, India; Department of Environmental Science, Savitribai Phule Pune University, Pune, 411007, India.
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Scoffone VC, Trespidi G, Barbieri G, Irudal S, Perrin E, Buroni S. Role of RND Efflux Pumps in Drug Resistance of Cystic Fibrosis Pathogens. Antibiotics (Basel) 2021; 10:863. [PMID: 34356783 PMCID: PMC8300704 DOI: 10.3390/antibiotics10070863] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 07/01/2021] [Accepted: 07/13/2021] [Indexed: 01/21/2023] Open
Abstract
Drug resistance represents a great concern among people with cystic fibrosis (CF), due to the recurrent and prolonged antibiotic therapy they should often undergo. Among Multi Drug Resistance (MDR) determinants, Resistance-Nodulation-cell Division (RND) efflux pumps have been reported as the main contributors, due to their ability to extrude a wide variety of molecules out of the bacterial cell. In this review, we summarize the principal RND efflux pump families described in CF pathogens, focusing on the main Gram-negative bacterial species (Pseudomonas aeruginosa, Burkholderia cenocepacia, Achromobacter xylosoxidans, Stenotrophomonas maltophilia) for which a predominant role of RND pumps has been associated to MDR phenotypes.
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Affiliation(s)
- Viola Camilla Scoffone
- Department of Biology and Biotechnology “Lazzaro Spallanzani”, University of Pavia, 27100 Pavia, Italy; (V.C.S.); (G.T.); (G.B.); (S.I.)
| | - Gabriele Trespidi
- Department of Biology and Biotechnology “Lazzaro Spallanzani”, University of Pavia, 27100 Pavia, Italy; (V.C.S.); (G.T.); (G.B.); (S.I.)
| | - Giulia Barbieri
- Department of Biology and Biotechnology “Lazzaro Spallanzani”, University of Pavia, 27100 Pavia, Italy; (V.C.S.); (G.T.); (G.B.); (S.I.)
| | - Samuele Irudal
- Department of Biology and Biotechnology “Lazzaro Spallanzani”, University of Pavia, 27100 Pavia, Italy; (V.C.S.); (G.T.); (G.B.); (S.I.)
| | - Elena Perrin
- Department of Biology, University of Florence, 50019 Sesto Fiorentino, Italy
| | - Silvia Buroni
- Department of Biology and Biotechnology “Lazzaro Spallanzani”, University of Pavia, 27100 Pavia, Italy; (V.C.S.); (G.T.); (G.B.); (S.I.)
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Rajapaksha P, Ojo I, Yang L, Pandeya A, Abeywansha T, Wei Y. Insight into the AcrAB-TolC Complex Assembly Process Learned from Competition Studies. Antibiotics (Basel) 2021; 10:antibiotics10070830. [PMID: 34356751 PMCID: PMC8300762 DOI: 10.3390/antibiotics10070830] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 06/30/2021] [Accepted: 07/06/2021] [Indexed: 11/16/2022] Open
Abstract
The RND family efflux pump AcrAB-TolC in E. coli and its homologs in other Gram-negative bacteria are major players in conferring multidrug resistance to the cells. While the structure of the pump complex has been elucidated with ever-increasing resolution through crystallography and Cryo-EM efforts, the dynamic assembly process remains poorly understood. Here, we tested the effect of overexpressing functionally defective pump components in wild type E. coli cells to probe the pump assembly process. Incorporation of a defective component is expected to reduce the efflux efficiency of the complex, leading to the so called "dominant negative" effect. Being one of the most intensively studied bacterial multidrug efflux pumps, many AcrA and AcrB mutations have been reported that disrupt efflux through different mechanisms. We examined five groups of AcrB and AcrA mutants, defective in different aspects of assembly and substrate efflux. We found that none of them demonstrated the expected dominant negative effect, even when expressed at concentrations many folds higher than their genomic counterpart. The assembly of the AcrAB-TolC complex appears to have a proof-read mechanism that effectively eliminated the formation of futile pump complex.
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Zwama M, Nishino K. Ever-Adapting RND Efflux Pumps in Gram-Negative Multidrug-Resistant Pathogens: A Race against Time. Antibiotics (Basel) 2021; 10:774. [PMID: 34201908 PMCID: PMC8300642 DOI: 10.3390/antibiotics10070774] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 06/11/2021] [Accepted: 06/14/2021] [Indexed: 01/13/2023] Open
Abstract
The rise in multidrug resistance (MDR) is one of the greatest threats to human health worldwide. MDR in bacterial pathogens is a major challenge in healthcare, as bacterial infections are becoming untreatable by commercially available antibiotics. One of the main causes of MDR is the over-expression of intrinsic and acquired multidrug efflux pumps, belonging to the resistance-nodulation-division (RND) superfamily, which can efflux a wide range of structurally different antibiotics. Besides over-expression, however, recent amino acid substitutions within the pumps themselves-causing an increased drug efflux efficiency-are causing additional worry. In this review, we take a closer look at clinically, environmentally and laboratory-evolved Gram-negative bacterial strains and their decreased drug sensitivity as a result of mutations directly in the RND-type pumps themselves (from Escherichia coli, Salmonella enterica, Neisseria gonorrhoeae, Pseudomonas aeruginosa, Acinetobacter baumannii and Legionella pneumophila). We also focus on the evolution of the efflux pumps by comparing hundreds of efflux pumps to determine where conservation is concentrated and where differences in amino acids can shed light on the broad and even broadening drug recognition. Knowledge of conservation, as well as of novel gain-of-function efflux pump mutations, is essential for the development of novel antibiotics and efflux pump inhibitors.
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Affiliation(s)
- Martijn Zwama
- SANKEN (The Institute of Scientific and Industrial Research), Osaka University, Ibaraki, Osaka 567-0047, Japan
| | - Kunihiko Nishino
- SANKEN (The Institute of Scientific and Industrial Research), Osaka University, Ibaraki, Osaka 567-0047, Japan
- Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565-0871, Japan
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48
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Huang P, Wang Z, Cai K, Wei L, Chu Y, Guo M, Fan E. Targeting Bacterial Membrane Proteins to Explore the Beneficial Effects of Natural Products: New Antibiotics against Drug Resistance. Curr Med Chem 2021; 29:2109-2126. [PMID: 34126882 DOI: 10.2174/0929867328666210614121222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 04/27/2021] [Accepted: 04/30/2021] [Indexed: 11/22/2022]
Abstract
Antibiotic resistance is currently a world health crisis that urges the development of new antibacterial substances. To this end, natural products, including flavonoids, alkaloids, terpenoids, steroids, peptides and organic acids that play a vital role in the development of medicines and thus constitute a rich source in clinical practices, provide an important source of drugs directly or for the screen of lead compounds for new antibiotic development. Because membrane proteins, which comprise more than 60% of the current clinical drug targets, play crucial roles in signal transduction, transport, bacterial pathogenicity and drug resistance, as well as immunogenicity, it is our aim to summarize those natural products with different structures that target bacterial membrane proteins, such as efflux pumps and enzymes, to provide an overview for the development of new antibiotics to deal with antibiotic resistance.
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Affiliation(s)
- Piying Huang
- State Key Laboratory of Medical Molecular Biology, Department of Microbiology and Parasitology, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Zhe Wang
- State Key Laboratory of Medical Molecular Biology, Department of Microbiology and Parasitology, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Kun Cai
- State Key Laboratory of Medical Molecular Biology, Department of Microbiology and Parasitology, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Liangwan Wei
- State Key Laboratory of Medical Molecular Biology, Department of Microbiology and Parasitology, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Yindi Chu
- State Key Laboratory of Medical Molecular Biology, Department of Microbiology and Parasitology, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Mingquan Guo
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Sino-Africa Joint Research Center, Chinese Academy of Sciences, Wuhan, China
| | - Enguo Fan
- State Key Laboratory of Medical Molecular Biology, Department of Microbiology and Parasitology, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
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49
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Alav I, Kobylka J, Kuth MS, Pos KM, Picard M, Blair JMA, Bavro VN. Structure, Assembly, and Function of Tripartite Efflux and Type 1 Secretion Systems in Gram-Negative Bacteria. Chem Rev 2021; 121:5479-5596. [PMID: 33909410 PMCID: PMC8277102 DOI: 10.1021/acs.chemrev.1c00055] [Citation(s) in RCA: 96] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Indexed: 12/11/2022]
Abstract
Tripartite efflux pumps and the related type 1 secretion systems (T1SSs) in Gram-negative organisms are diverse in function, energization, and structural organization. They form continuous conduits spanning both the inner and the outer membrane and are composed of three principal components-the energized inner membrane transporters (belonging to ABC, RND, and MFS families), the outer membrane factor channel-like proteins, and linking the two, the periplasmic adaptor proteins (PAPs), also known as the membrane fusion proteins (MFPs). In this review we summarize the recent advances in understanding of structural biology, function, and regulation of these systems, highlighting the previously undescribed role of PAPs in providing a common architectural scaffold across diverse families of transporters. Despite being built from a limited number of basic structural domains, these complexes present a staggering variety of architectures. While key insights have been derived from the RND transporter systems, a closer inspection of the operation and structural organization of different tripartite systems reveals unexpected analogies between them, including those formed around MFS- and ATP-driven transporters, suggesting that they operate around basic common principles. Based on that we are proposing a new integrated model of PAP-mediated communication within the conformational cycling of tripartite systems, which could be expanded to other types of assemblies.
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Affiliation(s)
- Ilyas Alav
- Institute
of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Jessica Kobylka
- Institute
of Biochemistry, Biocenter, Goethe Universität
Frankfurt, Max-von-Laue-Straße 9, D-60438 Frankfurt, Germany
| | - Miriam S. Kuth
- Institute
of Biochemistry, Biocenter, Goethe Universität
Frankfurt, Max-von-Laue-Straße 9, D-60438 Frankfurt, Germany
| | - Klaas M. Pos
- Institute
of Biochemistry, Biocenter, Goethe Universität
Frankfurt, Max-von-Laue-Straße 9, D-60438 Frankfurt, Germany
| | - Martin Picard
- Laboratoire
de Biologie Physico-Chimique des Protéines Membranaires, CNRS
UMR 7099, Université de Paris, 75005 Paris, France
- Fondation
Edmond de Rothschild pour le développement de la recherche
Scientifique, Institut de Biologie Physico-Chimique, 75005 Paris, France
| | - Jessica M. A. Blair
- Institute
of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Vassiliy N. Bavro
- School
of Life Sciences, University of Essex, Colchester, CO4 3SQ United Kingdom
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50
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Zgurskaya HI, Malloci G, Chandar B, Vargiu AV, Ruggerone P. Bacterial efflux transporters' polyspecificity - a gift and a curse? Curr Opin Microbiol 2021; 61:115-123. [PMID: 33940284 DOI: 10.1016/j.mib.2021.03.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 03/26/2021] [Accepted: 03/30/2021] [Indexed: 12/24/2022]
Abstract
All mechanisms of clinical antibiotic resistance benefit from activities of polyspecific efflux pumps acting to reduce intracellular accumulation of toxins and antibiotics. In Gram-negative bacteria, the major polyspecific efflux transporters belong to the Resistance-Nodulation-cell Division (RND) superfamily of proteins, which are capable of expelling thousands of structurally diverse compounds. Recent structural and functional advances generated novel insights into mechanisms underlying the biochemical versatility of RND transporters. This opinion article reviews these mechanisms and discusses implications of the polyspecificity of RND transporters for bacterial survival and for the development of efflux pump inhibitors effective in clinics.
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Affiliation(s)
- Helen I Zgurskaya
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK 73072, United States.
| | - Giuliano Malloci
- Department of Physics, University of Cagliari, 09042 Monserrato (Cagliari), Italy
| | - Brinda Chandar
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK 73072, United States
| | - Attilio V Vargiu
- Department of Physics, University of Cagliari, 09042 Monserrato (Cagliari), Italy
| | - Paolo Ruggerone
- Department of Physics, University of Cagliari, 09042 Monserrato (Cagliari), Italy
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