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Li Y, Shi X, Zeng M, Qin P, Fu M, Luo S, Tang C, Mo C, Yu F. Effect of polyethylene microplastics on antibiotic resistance genes: A comparison based on different soil types and plant types. JOURNAL OF HAZARDOUS MATERIALS 2024; 472:134581. [PMID: 38743972 DOI: 10.1016/j.jhazmat.2024.134581] [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: 02/24/2024] [Revised: 04/13/2024] [Accepted: 05/08/2024] [Indexed: 05/16/2024]
Abstract
Microplastics (MPs) and antibiotic resistance genes (ARGs) are two types of contaminants that are widely present in the soil environment. MPs can act as carriers of microbes, facilitating the colonization and spread of ARGs and thus posing potential hazards to ecosystem safety and human health. In the present study, we explored the microbial networks and ARG distribution characteristics in different soil types (heavy metal (HM)-contaminated soil and agricultural soil planted with different plants: Bidens pilosa L., Ipomoea aquatica F., and Brassica chinensis L.) after the application of MPs and evaluated environmental factors, potential microbial hosts, and ARGs. The microbial communities in the three rhizosphere soils were closely related to each other, and the modularity of the microbial networks was greater than 0.4. Moreover, the core taxa in the microbial networks, including Actinobacteriota, Proteobacteria, and Myxococcota, were important for resisting environmental stress. The ARG resistance mechanisms were dominated by antibiotic efflux in all three rhizosphere soils. Based on the annotation results, the MP treatments induced changes in the relative abundance of microbes carrying ARGs, and the G1-5 treatment significantly increased the abundance of MuxB in Verrucomicrobia, Elusimicrobia, Actinobacteria, Planctomycetes, and Acidobacteria. Path analysis showed that changes in MP particle size and dosage may indirectly affect soil enzyme activities by changing pH, which affects microbes and ARGs. We suggest that MPs may provide surfaces for ARG accumulation, leading to ARG enrichment in plants. In conclusion, our results demonstrate that MPs, as potentially persistent pollutants, can affect different types of soil environments and that the presence of ARGs may cause substantial environmental risks.
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Affiliation(s)
- Yi Li
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, Guilin, China; College of Environment and Resources, Guangxi Normal University, Guilin, China; Guangxi Key Laboratory of Environmental Processes and Remediation in Ecologically Fragile Regions, Guangxi Normal University, Guilin, China
| | - Xinwei Shi
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, Guilin, China; College of Environment and Resources, Guangxi Normal University, Guilin, China; Guangxi Key Laboratory of Environmental Processes and Remediation in Ecologically Fragile Regions, Guangxi Normal University, Guilin, China
| | - Meng Zeng
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, Guilin, China; College of Environment and Resources, Guangxi Normal University, Guilin, China
| | - Peiqing Qin
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, Guilin, China; College of Environment and Resources, Guangxi Normal University, Guilin, China
| | - Mingyue Fu
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, Guilin, China; College of Environment and Resources, Guangxi Normal University, Guilin, China
| | - Shiyu Luo
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, Guilin, China; College of Environment and Resources, Guangxi Normal University, Guilin, China
| | - Chijian Tang
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, Guilin, China; College of Environment and Resources, Guangxi Normal University, Guilin, China
| | - Cuiju Mo
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, Guilin, China; College of Environment and Resources, Guangxi Normal University, Guilin, China
| | - Fangming Yu
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, Guilin, China; College of Environment and Resources, Guangxi Normal University, Guilin, China; Guangxi Key Laboratory of Environmental Processes and Remediation in Ecologically Fragile Regions, Guangxi Normal University, Guilin, China.
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Mahey N, Tambat R, Kalia R, Ingavale R, Kodesia A, Chandal N, Kapoor S, Verma DK, Thakur KG, Jachak S, Nandanwar H. Pyrrole-based inhibitors of RND-type efflux pumps reverse antibiotic resistance and display anti-virulence potential. PLoS Pathog 2024; 20:e1012121. [PMID: 38593161 PMCID: PMC11003683 DOI: 10.1371/journal.ppat.1012121] [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: 09/08/2023] [Accepted: 03/13/2024] [Indexed: 04/11/2024] Open
Abstract
Efflux pumps of the resistance-nodulation-cell division (RND) superfamily, particularly the AcrAB-TolC, and MexAB-OprM, besides mediating intrinsic and acquired resistance, also intervene in bacterial pathogenicity. Inhibitors of such pumps could restore the activities of antibiotics and curb bacterial virulence. Here, we identify pyrrole-based compounds that boost antibiotic activity in Escherichia coli and Pseudomonas aeruginosa by inhibiting their archetype RND transporters. Molecular docking and biophysical studies revealed that the EPIs bind to AcrB. The identified efflux pump inhibitors (EPIs) inhibit the efflux of fluorescent probes, attenuate persister formation, extend post-antibiotic effect, and diminish resistant mutant development. The bacterial membranes remained intact upon exposure to the EPIs. EPIs also possess an anti-pathogenic potential and attenuate P. aeruginosa virulence in vivo. The intracellular invasion of E. coli and P. aeruginosa inside the macrophages was hampered upon treatment with the lead EPI. The excellent efficacy of the EPI-antibiotic combination was evidenced in animal lung infection and sepsis protection models. These findings indicate that EPIs discovered herein with negligible toxicity are potential antibiotic adjuvants to address life-threatening Gram-negative bacterial infections.
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Affiliation(s)
- Nisha Mahey
- Clinical Microbiology & Antimicrobial Research Laboratory, CSIR-Institute of Microbial Technology, Sector 39-A, Chandigarh, India
- Academy of Scientific & Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, India
| | - Rushikesh Tambat
- Clinical Microbiology & Antimicrobial Research Laboratory, CSIR-Institute of Microbial Technology, Sector 39-A, Chandigarh, India
| | - Ritu Kalia
- Department of Natural Products, National Institute of Pharmaceutical Education and Research, Mohali, India
| | - Rajnita Ingavale
- Department of Natural Products, National Institute of Pharmaceutical Education and Research, Mohali, India
| | - Akriti Kodesia
- Academy of Scientific & Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, India
- Structural Biology Laboratory, CSIR-Institute of Microbial Technology, Chandigarh, India
| | - Nishtha Chandal
- Clinical Microbiology & Antimicrobial Research Laboratory, CSIR-Institute of Microbial Technology, Sector 39-A, Chandigarh, India
- Academy of Scientific & Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, India
| | - Srajan Kapoor
- Structural Biology Laboratory, CSIR-Institute of Microbial Technology, Chandigarh, India
| | - Dipesh Kumar Verma
- Structural Biology Laboratory, CSIR-Institute of Microbial Technology, Chandigarh, India
| | - Krishan Gopal Thakur
- Structural Biology Laboratory, CSIR-Institute of Microbial Technology, Chandigarh, India
| | - Sanjay Jachak
- Department of Natural Products, National Institute of Pharmaceutical Education and Research, Mohali, India
| | - Hemraj Nandanwar
- Clinical Microbiology & Antimicrobial Research Laboratory, CSIR-Institute of Microbial Technology, Sector 39-A, Chandigarh, India
- Academy of Scientific & Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, India
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Shiraliyev R, Orman MA. METABOLIC DISRUPTION IMPAIRS RIBOSOMAL PROTEIN LEVELS, RESULTING IN ENHANCED AMINOGLYCOSIDE TOLERANCE. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.12.20.572673. [PMID: 38187583 PMCID: PMC10769322 DOI: 10.1101/2023.12.20.572673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Aminoglycoside antibiotics display broad-spectrum activity against Gram-negative and Gram-positive bacteria by targeting their ribosomes. Herein, we have demonstrated that energy metabolism plays a crucial role in aminoglycoside tolerance, as knockout strains associated with the tricarboxylic acid cycle (TCA) and the electron transport chain (ETC) exhibited increased tolerance to aminoglycosides in the mid-exponential growth phase of Escherichia coli cells. Given that aminoglycoside uptake relies on the energy-driven electrochemical potential across the cytoplasmic membrane, our initial expectation was that these genetic perturbations would decrease the proton motive force (PMF), subsequently affecting the uptake of aminoglycosides. However, our results did not corroborate this assumption. We found no consistent metabolic changes, ATP levels, cytoplasmic pH variations, or membrane potential differences in the mutant strains compared to the wild type. Additionally, intracellular concentrations of fluorophore-labeled gentamicin remained similar across all strains. To uncover the mechanism responsible for the observed tolerance in mutant strains, we employed untargeted mass spectrometry to quantify the proteins within these mutants and subsequently compared them to their wild-type counterparts. Our comprehensive analysis, which encompassed protein-protein association networks and functional enrichment, unveiled a noteworthy upregulation of proteins linked to the TCA cycle in the mutant strains during the mid-exponential growth phase, suggesting that these strains compensate for the perturbation in their energy metabolism by increasing TCA cycle activity to maintain their membrane potential and ATP levels. Furthermore, our pathway enrichment analysis shed light on local network clusters displaying downregulation across all mutant strains, which were associated with both large and small ribosomal binding proteins, ribosome biogenesis, translation factor activity, and the biosynthesis of ribonucleoside monophosphates. These findings offer a plausible explanation for the observed tolerance of aminoglycosides in the mutant strains. Altogether, this research has the potential to uncover mechanisms behind aminoglycoside tolerance, paving the way for novel strategies to combat such cells.
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Affiliation(s)
- Rauf Shiraliyev
- William A. Brookshire Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX, 77204
| | - Mehmet A Orman
- William A. Brookshire Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX, 77204
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Jiang C, Zhao Z, Zhu D, Pan X, Yang Y. Rare resistome rather than core resistome exhibited higher diversity and risk along the Yangtze River. WATER RESEARCH 2024; 249:120911. [PMID: 38039820 DOI: 10.1016/j.watres.2023.120911] [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: 08/03/2023] [Revised: 11/09/2023] [Accepted: 11/21/2023] [Indexed: 12/03/2023]
Abstract
As important freshwater ecosystems, the occurrence and distribution of antibiotic resistance genes (ARGs) in rivers are relevant to public health. However, studies investigating ARGs of different environmental media in river ecosystems are limited. In this study, we analyzed the ARGs of microbes in free-living setting, particle-associated setting, sediment and bank soil of the Yangtze River using metagenomics. Twenty-six ARGs were found in all samples regardless of media (core resistome) with a diversity of 8.6 %-34.7 %, accounting for 22.7 %-89.2 % of the relative abundance of the overall ARGs. The core resistome of the Yangtze River was dominated by multidrug resistance genes consisting mainly of efflux pumps and bacitracin resistance genes. The rare resistome was dominated by multidrug, sulfonamide, and aminoglycoside resistance genes. The core resistome was more prevalent in chromosomes, implying that these ARGs with low diversity and high relative abundance may be intrinsic to microbes in the Yangtze River. The rare resistome was more prevalent in plasmids, suggesting these ARGs with high diversity and low relative abundance were acquired under environmental stresses and had transfer potential. Additionally, we found that core and rare resistome were mainly carried by specific bacteria. Noteworthily, twenty-two ARGs of high clinical concern were identified in rare resistome, especially aac(6')-I, sul1, and tetM, which were plasmid-borne and hosted by clinically relevant pathogens. Both core and rare resistome hosts showed the highest niche breadths in particle-associated setting compared to other media, and particle-associated setting could provide more stable and ideal conditions for resistome hosts to survive. This study elucidated the genetic locations of ARGs and the community assembly mechanisms of ARG hosts in freshwater environments.
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Affiliation(s)
- Chunxia Jiang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China; University of Chinese Academy of Sciences, Beijing 100049, China; Danjiangkou Wetland Ecosystem Field Scientific Observation and Research Station, Chinese Academy of Sciences & Hubei Province, Wuhan 430074, China
| | - Zelong Zhao
- Liaoning Key Laboratory of Marine Fishery Molecular Biology, Liaoning Key Lab of Germplasm Improvement and Fine Seed Breeding of Marine Aquatic Animals, Liaoning Ocean and Fisheries Science Research Institute, Dalian 116023, China
| | - Dong Zhu
- Key Laboratory of Urban Environment and Health, Ningbo Urban Environment Observation and Research Station, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Xiong Pan
- Basin Water Environmental Research Department, Changjiang River Scientific Research Institute, Wuhan, 430014, China
| | - Yuyi Yang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China; University of Chinese Academy of Sciences, Beijing 100049, China; Danjiangkou Wetland Ecosystem Field Scientific Observation and Research Station, Chinese Academy of Sciences & Hubei Province, Wuhan 430074, China.
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5
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Ricaurte D, Huang Y, Sheth RU, Gelsinger DR, Kaufman A, Wang HH. High-throughput transcriptomics of 409 bacteria-drug pairs reveals drivers of gut microbiota perturbation. Nat Microbiol 2024; 9:561-575. [PMID: 38233648 DOI: 10.1038/s41564-023-01581-x] [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: 03/06/2023] [Accepted: 12/08/2023] [Indexed: 01/19/2024]
Abstract
Many drugs can perturb the gut microbiome, potentially leading to negative health consequences. However, mechanisms of most microorganism-drug responses have not been elucidated at the genetic level. Using high-throughput bacterial transcriptomics, we systematically characterized the gene expression profiles of prevalent human gut bacteria exposed to the most frequently prescribed orally administered pharmaceuticals. Across >400 drug-microorganism pairs, significant and reproducible transcriptional responses were observed, including pathways involved in multidrug resistance, metabolite transport, tartrate metabolism and riboflavin biosynthesis. Importantly, we discovered that statin-mediated upregulation of the AcrAB-TolC efflux pump in Bacteroidales species enhances microbial sensitivity to vitamin A and secondary bile acids. Moreover, gut bacteria carrying acrAB-tolC genes are depleted in patients taking simvastatin, suggesting that drug-efflux interactions generate collateral toxicity that depletes pump-containing microorganisms from patient microbiomes. This study provides a resource to further understand the drivers of drug-mediated microbiota shifts for better informed clinical interventions.
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Affiliation(s)
- Deirdre Ricaurte
- Department of Systems Biology, Columbia University, New York, NY, USA
- Integrated Program in Cellular, Molecular, and Biomedical Studies, Columbia University, New York, NY, USA
| | - Yiming Huang
- Department of Systems Biology, Columbia University, New York, NY, USA
- Integrated Program in Cellular, Molecular, and Biomedical Studies, Columbia University, New York, NY, USA
| | - Ravi U Sheth
- Department of Systems Biology, Columbia University, New York, NY, USA
- Integrated Program in Cellular, Molecular, and Biomedical Studies, Columbia University, New York, NY, USA
| | | | - Andrew Kaufman
- Department of Systems Biology, Columbia University, New York, NY, USA
| | - Harris H Wang
- Department of Systems Biology, Columbia University, New York, NY, USA.
- Department of Pathology and Cell Biology, Columbia University, New York, NY, USA.
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6
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Tague N, Coriano-Ortiz C, Sheets MB, Dunlop MJ. Light-inducible protein degradation in E. coli with the LOVdeg tag. eLife 2024; 12:RP87303. [PMID: 38270583 PMCID: PMC10945698 DOI: 10.7554/elife.87303] [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] [Indexed: 01/26/2024] Open
Abstract
Molecular tools for optogenetic control allow for spatial and temporal regulation of cell behavior. In particular, light-controlled protein degradation is a valuable mechanism of regulation because it can be highly modular, used in tandem with other control mechanisms, and maintain functionality throughout growth phases. Here, we engineered LOVdeg, a tag that can be appended to a protein of interest for inducible degradation in Escherichia coli using blue light. We demonstrate the modularity of LOVdeg by using it to tag a range of proteins, including the LacI repressor, CRISPRa activator, and the AcrB efflux pump. Additionally, we demonstrate the utility of pairing the LOVdeg tag with existing optogenetic tools to enhance performance by developing a combined EL222 and LOVdeg system. Finally, we use the LOVdeg tag in a metabolic engineering application to demonstrate post-translational control of metabolism. Together, our results highlight the modularity and functionality of the LOVdeg tag system and introduce a powerful new tool for bacterial optogenetics.
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Affiliation(s)
- Nathan Tague
- Department of Biomedical Engineering, Boston UniversityBostonUnited States
- Biological Design Center, Boston UniversityBostonUnited States
| | - Cristian Coriano-Ortiz
- Department of Biomedical Engineering, Boston UniversityBostonUnited States
- Biological Design Center, Boston UniversityBostonUnited States
| | - Michael B Sheets
- Department of Biomedical Engineering, Boston UniversityBostonUnited States
- Biological Design Center, Boston UniversityBostonUnited States
| | - Mary J Dunlop
- Department of Biomedical Engineering, Boston UniversityBostonUnited States
- Biological Design Center, Boston UniversityBostonUnited States
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7
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Dai JS, Xu J, Shen HJ, Chen NP, Zhu BQ, Xue ZJ, Chen HH, Ding ZS, Ding R, Qian CD. The induced and intrinsic resistance of Escherichia coli to sanguinarine is mediated by AcrB efflux pump. Microbiol Spectr 2024; 12:e0323723. [PMID: 38038452 PMCID: PMC10783092 DOI: 10.1128/spectrum.03237-23] [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: 09/20/2023] [Accepted: 10/31/2023] [Indexed: 12/02/2023] Open
Abstract
IMPORTANCE The use of plant extracts is increasing as an alternative to synthetic compounds, especially antibiotics. However, there is no sufficient knowledge on the mechanisms and potential risks of antibiotic resistance induced by these phytochemicals. In the present study, we found that stable drug resistant mutants of E. coli emerged after repetitive exposure to sanguinarine and demonstrated that the AcrB efflux pump contributed to the emerging of induced and intrinsic resistance of E. coli to this phytochemical. Our results offered some insights into comprehending and preventing the onset of drug-resistant strains when utilizing products containing sanguinarine.
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Affiliation(s)
- Jian-Sheng Dai
- College of Life Sciences, Zhejiang Chinese Medical University, Hangzhou, China
| | - Jian Xu
- College of Life Sciences, Zhejiang Chinese Medical University, Hangzhou, China
| | - Hao-Jie Shen
- College of Life Sciences, Zhejiang Chinese Medical University, Hangzhou, China
| | - Ni-Pi Chen
- College of Life Sciences, Zhejiang Chinese Medical University, Hangzhou, China
| | - Bing-Qi Zhu
- College of Medical Technology, Zhejiang Chinese Medical University, Hangzhou, China
| | - Zheng-Jie Xue
- College of Life Sciences, Zhejiang Chinese Medical University, Hangzhou, China
| | - Hao-Han Chen
- College of Life Sciences, Zhejiang Chinese Medical University, Hangzhou, China
| | - Zhi-Shan Ding
- College of Medical Technology, Zhejiang Chinese Medical University, Hangzhou, China
| | - Rui Ding
- School of Life Sciences, Anhui Medical University, Hefei, China
| | - Chao-Dong Qian
- College of Life Sciences, Zhejiang Chinese Medical University, Hangzhou, China
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8
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Kyono Y, Magboo JD, Daley EA, Flowers SA. Antipsychotic quetiapine alters the mouse fecal resistome by impacting antibiotic efflux, cell membrane, and cell wall synthesis genes. Microbiol Spectr 2024; 12:e0380423. [PMID: 38099619 PMCID: PMC10782992 DOI: 10.1128/spectrum.03804-23] [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: 11/02/2023] [Accepted: 11/16/2023] [Indexed: 01/13/2024] Open
Abstract
IMPORTANCE This study significantly contributes to our understanding of how certain medications can unintentionally contribute to a major global health issue, i.e., antibiotic resistance. Quetiapine, a widely used antipsychotic medication, was found to increase key resistance mechanisms of gut bacteria to antibiotics in mice. Specifically, these data suggest that quetiapine may target elements of the bacterial cell membrane. If similar effects are found in humans, this medicine could unexpectedly make it harder to treat certain infections. This research emphasizes the importance of being mindful about not just antibiotics themselves, but also about other medications that could inadvertently contribute to this problem. Ultimately, these findings underline the necessity for more in-depth research on the broader impact of pharmaceuticals.
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Affiliation(s)
- Yasuhiro Kyono
- Department of Pharmacy Practice, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Jonathan D. Magboo
- Department of Pharmacy Practice, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Elizabeth A. Daley
- Department of Pharmacy Practice, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Stephanie A. Flowers
- Department of Pharmacy Practice, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois, USA
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9
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Vieira Da Cruz A, Jiménez-Castellanos JC, Börnsen C, Van Maele L, Compagne N, Pradel E, Müller RT, Meurillon V, Soulard D, Piveteau C, Biela A, Dumont J, Leroux F, Deprez B, Willand N, Pos KM, Frangakis AS, Hartkoorn RC, Flipo M. Pyridylpiperazine efflux pump inhibitor boosts in vivo antibiotic efficacy against K. pneumoniae. EMBO Mol Med 2024; 16:93-111. [PMID: 38177534 PMCID: PMC10897476 DOI: 10.1038/s44321-023-00007-9] [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: 07/03/2023] [Revised: 11/09/2023] [Accepted: 11/17/2023] [Indexed: 01/06/2024] Open
Abstract
Antimicrobial resistance is a global problem, rendering conventional treatments less effective and requiring innovative strategies to combat this growing threat. The tripartite AcrAB-TolC efflux pump is the dominant constitutive system by which Enterobacterales like Escherichia coli and Klebsiella pneumoniae extrude antibiotics. Here, we describe the medicinal chemistry development and drug-like properties of BDM91288, a pyridylpiperazine-based AcrB efflux pump inhibitor. In vitro evaluation of BDM91288 confirmed it to potentiate the activity of a panel of antibiotics against K. pneumoniae as well as revert clinically relevant antibiotic resistance mediated by acrAB-tolC overexpression. Using cryo-EM, BDM91288 binding to the transmembrane region of K. pneumoniae AcrB was confirmed, further validating the mechanism of action of this inhibitor. Finally, proof of concept studies demonstrated that oral administration of BDM91288 significantly potentiated the in vivo efficacy of levofloxacin treatment in a murine model of K. pneumoniae lung infection.
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Affiliation(s)
- Anais Vieira Da Cruz
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177 - Drugs and Molecules for Living Systems, F-59000, Lille, France
| | - Juan-Carlos Jiménez-Castellanos
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 9017 - CIIL - Center for Infection and Immunity of Lille, F-59000, Lille, France
| | - Clara Börnsen
- Buchmann Institute for Molecular Life Sciences and Institute for Biophysics, Goethe University Frankfurt, Max-von-Laue-Str. 15, D-60438, Frankfurt am Main, Germany
| | - Laurye Van Maele
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 9017 - CIIL - Center for Infection and Immunity of Lille, F-59000, Lille, France
| | - Nina Compagne
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177 - Drugs and Molecules for Living Systems, F-59000, Lille, France
| | - Elizabeth Pradel
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 9017 - CIIL - Center for Infection and Immunity of Lille, F-59000, Lille, France
| | - Reinke T Müller
- Institute of Biochemistry, Goethe-University Frankfurt, Max-von-Laue-Str. 9, D-60438, Frankfurt am Main, Germany
| | - Virginie Meurillon
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177 - Drugs and Molecules for Living Systems, F-59000, Lille, France
| | - Daphnée Soulard
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 9017 - CIIL - Center for Infection and Immunity of Lille, F-59000, Lille, France
| | - Catherine Piveteau
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177 - Drugs and Molecules for Living Systems, F-59000, Lille, France
| | - Alexandre Biela
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177 - Drugs and Molecules for Living Systems, F-59000, Lille, France
| | - Julie Dumont
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177 - Drugs and Molecules for Living Systems, F-59000, Lille, France
| | - Florence Leroux
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177 - Drugs and Molecules for Living Systems, F-59000, Lille, France
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur Lille, US 41-UAR 2014-PLBS, F-59000, Lille, France
| | - Benoit Deprez
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177 - Drugs and Molecules for Living Systems, F-59000, Lille, France
| | - Nicolas Willand
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177 - Drugs and Molecules for Living Systems, F-59000, Lille, France
| | - Klaas M Pos
- Institute of Biochemistry, Goethe-University Frankfurt, Max-von-Laue-Str. 9, D-60438, Frankfurt am Main, Germany.
| | - Achilleas S Frangakis
- Buchmann Institute for Molecular Life Sciences and Institute for Biophysics, Goethe University Frankfurt, Max-von-Laue-Str. 15, D-60438, Frankfurt am Main, Germany.
| | - Ruben C Hartkoorn
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 9017 - CIIL - Center for Infection and Immunity of Lille, F-59000, Lille, France.
| | - Marion Flipo
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177 - Drugs and Molecules for Living Systems, F-59000, Lille, France.
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10
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Turbant F, Esnouf E, Rosaz F, Wien F, Węgrzyn G, Chauvet H, Arluison V. Role of the Bacterial Amyloid-like Hfq in Fluoroquinolone Fluxes. Microorganisms 2023; 12:53. [PMID: 38257880 PMCID: PMC10819720 DOI: 10.3390/microorganisms12010053] [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: 11/29/2023] [Revised: 12/22/2023] [Accepted: 12/26/2023] [Indexed: 01/24/2024] Open
Abstract
Due to their two-cell membranes, Gram-negative bacteria are particularly resistant to antibiotics. Recent investigations aimed at exploring new target proteins involved in Gram-negative bacteria adaptation helped to identify environmental changes encountered during infection. One of the most promising approaches in finding novel targets for antibacterial drugs consists of blocking noncoding RNA-based regulation using the protein cofactor, Hfq. Although Hfq is important in many bacterial pathogens, its involvement in antibiotics response is still unclear. Indeed, Hfq may mediate drug resistance by regulating the major efflux system in Escherichia coli, but it could also play a role in the influx of antibiotics. Here, using an imaging approach, we addressed this problem quantitatively at the single-cell level. More precisely, we analyzed how Hfq affects the dynamic influx and efflux of ciprofloxacin, an antibiotic from the group of fluoroquinolones that is used to treat bacterial infections. Our results indicated that the absence of either whole Hfq or its C-terminal domain resulted in a more effective accumulation of ciprofloxacin, irrespective of the presence of the functional AcrAB-TolC efflux pump. However, overproduction of the MicF small regulatory RNA, which reduces the efficiency of expression of the ompF gene (coding for a porin involved in antibiotics influx) in a Hfq-dependent manner, resulted in impaired accumulation of ciprofloxacin. These results led us to propose potential mechanisms of action of Hfq in the regulation of fluoroquinolone fluxes across the E. coli envelope.
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Affiliation(s)
- Florian Turbant
- Synchrotron SOLEIL, L’Orme des Merisiers, Saint Aubin BP48, 91192 Gif-sur-Yvette, France; (F.T.); (F.W.); (H.C.)
- Laboratoire Léon Brillouin LLB, UMR12 CEA CNRS, CEA Saclay, 91191 Gif-sur-Yvette, France; (E.E.); (F.R.)
- Department of Molecular Biology, Faculty of Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland;
| | - Emeline Esnouf
- Laboratoire Léon Brillouin LLB, UMR12 CEA CNRS, CEA Saclay, 91191 Gif-sur-Yvette, France; (E.E.); (F.R.)
| | - Francois Rosaz
- Laboratoire Léon Brillouin LLB, UMR12 CEA CNRS, CEA Saclay, 91191 Gif-sur-Yvette, France; (E.E.); (F.R.)
| | - Frank Wien
- Synchrotron SOLEIL, L’Orme des Merisiers, Saint Aubin BP48, 91192 Gif-sur-Yvette, France; (F.T.); (F.W.); (H.C.)
| | - Grzegorz Węgrzyn
- Department of Molecular Biology, Faculty of Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland;
| | - Hugo Chauvet
- Synchrotron SOLEIL, L’Orme des Merisiers, Saint Aubin BP48, 91192 Gif-sur-Yvette, France; (F.T.); (F.W.); (H.C.)
| | - Véronique Arluison
- Laboratoire Léon Brillouin LLB, UMR12 CEA CNRS, CEA Saclay, 91191 Gif-sur-Yvette, France; (E.E.); (F.R.)
- UFR SDV, Université Paris Cité, 75013 Paris, France
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11
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Scheeder A, Brockhoff M, Ward EN, Kaminski Schierle GS, Mela I, Kaminski CF. Molecular Mechanisms of Cationic Fusogenic Liposome Interactions with Bacterial Envelopes. J Am Chem Soc 2023; 145:28240-28250. [PMID: 38085801 PMCID: PMC10755748 DOI: 10.1021/jacs.3c11463] [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: 10/17/2023] [Revised: 11/22/2023] [Accepted: 11/27/2023] [Indexed: 12/28/2023]
Abstract
Although fusogenic liposomes offer a promising approach for the delivery of antibiotic payloads across the cell envelope of Gram-negative bacteria, there is still a limited understanding of the individual nanocarrier interactions with the bacterial target. Using super-resolution microscopy, we characterize the interaction dynamics of positively charged fusogenic liposomes with Gram-negative (Escherichia coli) and Gram-positive (Bacillus subtilis) bacteria. The liposomes merge with the outer membrane (OM) of Gram-negative bacteria, while attachment or lipid internalization is observed in Gram-positive cells. Employing total internal reflection fluorescence microscopy, we demonstrated liposome fusion with model supported lipid bilayers. For whole E. coli cells, however, we observed heterogeneous membrane integrations, primarily involving liposome attachment and hemifusion events. With increasing lipopolysaccharide length, the likelihood of full-fusion events was reduced. The integration of artificial lipids into the OM of Gram-negative cells led to membrane destabilization, resulting in decreased bacterial vitality, membrane detachment, and improved codelivery of vancomycin─an effective antibiotic against Gram-positive cells. These findings provide significant insights into the interactions of individual nanocarriers with bacterial envelopes at the single-cell level, uncovering effects that would be missed in bulk measurements. This highlights the importance of conducting single-particle and single-cell investigations to assess the performance of next-generation drug delivery platforms.
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Affiliation(s)
- Anna Scheeder
- Department
of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge CB3 0AS, U.K.
| | - Marius Brockhoff
- Department
of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge CB3 0AS, U.K.
| | - Edward N. Ward
- Department
of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge CB3 0AS, U.K.
| | - Gabriele S. Kaminski Schierle
- Department
of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge CB3 0AS, U.K.
| | - Ioanna Mela
- Department
of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, U.K.
| | - Clemens F. Kaminski
- Department
of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge CB3 0AS, U.K.
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12
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Malekian N, Sainath S, Al-Fatlawi A, Schroeder M. Word-based GWAS harnesses the rich potential of genomic data for E. coli quinolone resistance. Front Microbiol 2023; 14:1276332. [PMID: 38152371 PMCID: PMC10751334 DOI: 10.3389/fmicb.2023.1276332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 11/16/2023] [Indexed: 12/29/2023] Open
Abstract
Quinolone resistance presents a growing global health threat. We employed word-based GWAS to explore genomic data, aiming to enhance our understanding of this phenomenon. Unlike traditional variant-based GWAS analyses, this approach simultaneously captures multiple genomic factors, including single and interacting resistance mutations and genes. Analyzing a dataset of 92 genomic E. coli samples from a wastewater treatment plant in Dresden, we identified 54 DNA unitigs significantly associated with quinolone resistance. Remarkably, our analysis not only validated known mutations in gyrA and parC genes and the results of our variant-based GWAS but also revealed new (mutated) genes such as mdfA, the AcrEF-TolC multidrug efflux system, ptrB, and hisI, implicated in antibiotic resistance. Furthermore, our study identified joint mutations in 14 genes including the known gyrA gene, providing insights into potential synergistic effects contributing to quinolone resistance. These findings showcase the exceptional capabilities of word-based GWAS in unraveling the intricate genomic foundations of quinolone resistance.
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Affiliation(s)
- Negin Malekian
- Biotechnology Center (BIOTEC), Technische Universität Dresden, Dresden, Germany
| | - Srividhya Sainath
- Biotechnology Center (BIOTEC), Technische Universität Dresden, Dresden, Germany
| | - Ali Al-Fatlawi
- Biotechnology Center (BIOTEC), Technische Universität Dresden, Dresden, Germany
- ITRDC, University of Kufa, Najaf, Iraq
| | - Michael Schroeder
- Biotechnology Center (BIOTEC), Technische Universität Dresden, Dresden, Germany
- Center for Scalable Data Analytics and Artificial Intelligence (ScaDS.AI), TU Dresden, Dresden, Germany
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13
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Chubiz LM. The Mar, Sox, and Rob Systems. EcoSal Plus 2023; 11:eesp00102022. [PMID: 37220096 DOI: 10.1128/ecosalplus.esp-0010-2022] [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: 09/14/2022] [Accepted: 03/03/2023] [Indexed: 01/28/2024]
Abstract
Environments inhabited by Enterobacteriaceae are diverse and often stressful. This is particularly true for Escherichia coli and Salmonella during host association in the gastrointestinal systems of animals. There, E. coli and Salmonella must survive exposure to various antimicrobial compounds produced or ingested by their host. A myriad of changes to cellular physiology and metabolism are required to achieve this feat. A central regulatory network responsible for sensing and responding to intracellular chemical stressors like antibiotics are the Mar, Sox, and Rob systems found throughout the Enterobacteriaceae. Each of these distinct regulatory networks controls expression of an overlapping set of downstream genes whose collective effects result in increased resistance to a wide array of antimicrobial compounds. This collection of genes is known as the mar-sox-rob regulon. This review will provide an overview of the mar-sox-rob regulon and molecular architecture of the Mar, Sox, and Rob systems.
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Affiliation(s)
- Lon M Chubiz
- Department of Biology, University of Missouri-St. Louis, St. Louis, Missouri, USA
- Biochemistry and Biotechnology Program, University of Missouri-St. Louis, St. Louis, Missouri, USA
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14
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Namikawa H, Imoto W, Yamada K, Tochino Y, Kaneko Y, Kakeya H, Shuto T. Predictors for onset of extended-spectrum beta-lactamase-producing Escherichia coli-induced bacteraemia: a systematic review and meta-analysis. J Hosp Infect 2023; 142:88-95. [PMID: 37802238 DOI: 10.1016/j.jhin.2023.09.017] [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: 06/22/2023] [Revised: 09/18/2023] [Accepted: 09/21/2023] [Indexed: 10/08/2023]
Abstract
Extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli bacteraemia can induce unfavourable clinical outcomes due to delay in appropriate antimicrobial treatment and limited therapeutic options. Therefore, elucidating the predictors of ESBL-producing E. coli-induced bacteraemia is crucial to improve clinical outcomes. However, a literature search did not reveal any studies that incorporate a meta-analysis of the predictors of ESBL-producing E. coli-induced bacteraemia. As such, this review was undertaken to assess current evidence on the predictors of ESBL-producing E. coli-induced bacteraemia. PubMed, Web of Science and Cochrane Library databases were searched for all relevant publications from January 2000 to September 2021. This systematic review evaluated 10 observational studies, comprising a total of 2325 patients with E. coli-induced bacteraemia and 850 (36.6%) ESBL-producing strains. In the meta-analysis, previous antibiotic therapy [pooled risk ratio (RR) 2.72; P<0.001], especially with cephalosporins (pooled RR 4.66; P<0.001) and quinolones (pooled RR 5.47; P<0.001), and urinary catheter use (pooled RR 3.79; P<0.001) were predictive of ESBL-producing E. coli-induced bacteraemia. Antibiotic therapy for patients with the above-mentioned risk factors should be selected considering the possibility of ESBL-producing E. coli-induced bacteraemia compared with non-ESBL-producing E. coli-induced bacteraemia. It is important to elucidate whether appropriate modulation of the identified risk factors can potentially mitigate the risk of ESBL-producing E. coli-induced bacteraemia compared with non-ESBL-producing E. coli-induced bacteraemia.
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Affiliation(s)
- H Namikawa
- Department of Medical Education and General Practice, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan.
| | - W Imoto
- Department of Infection Control Science, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan
| | - K Yamada
- Department of Infection Control Science, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan; Research Centre for Infectious Disease Sciences, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
| | - Y Tochino
- Department of Medical Education and General Practice, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan
| | - Y Kaneko
- Research Centre for Infectious Disease Sciences, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan; Department of Bacteriology, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan
| | - H Kakeya
- Department of Infection Control Science, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan; Research Centre for Infectious Disease Sciences, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
| | - T Shuto
- Department of Medical Education and General Practice, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan
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15
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Miele L, Evans RML, Cunniffe NJ, Torres-Barceló C, Bevacqua D. Evolutionary Epidemiology Consequences of Trait-Dependent Control of Heterogeneous Parasites. Am Nat 2023; 202:E130-E146. [PMID: 37963120 DOI: 10.1086/726062] [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: 11/16/2023]
Abstract
AbstractDisease control can induce both demographic and evolutionary responses in host-parasite systems. Foreseeing the outcome of control therefore requires knowledge of the eco-evolutionary feedback between control and system. Previous work has assumed that control strategies have a homogeneous effect on the parasite population. However, this is not true when control targets those traits that confer to the parasite heterogeneous levels of resistance, which can additionally be related to other key parasite traits through evolutionary trade-offs. In this work, we develop a minimal model coupling epidemiological and evolutionary dynamics to explore possible trait-dependent effects of control strategies. In particular, we consider a parasite expressing continuous levels of a trait-determining resource exploitation and a control treatment that can be either positively or negatively correlated with that trait. We demonstrate the potential of trait-dependent control by considering that the decision maker may want to minimize both the damage caused by the disease and the use of treatment, due to possible environmental or economic costs. We identify efficient strategies showing that the optimal type of treatment depends on the amount applied. Our results pave the way for the study of control strategies based on evolutionary constraints, such as collateral sensitivity and resistance costs, which are receiving increasing attention for both public health and agricultural purposes.
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16
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Tague N, Coriano-Ortiz C, Sheets MB, Dunlop MJ. Light inducible protein degradation in E. coli with the LOVdeg tag. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.25.530042. [PMID: 36865169 PMCID: PMC9980293 DOI: 10.1101/2023.02.25.530042] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
Molecular tools for optogenetic control allow for spatial and temporal regulation of cell behavior. In particular, light controlled protein degradation is a valuable mechanism of regulation because it can be highly modular, used in tandem with other control mechanisms, and maintain functionality throughout growth phases. Here, we engineered LOVdeg, a tag that can be appended to a protein of interest for inducible degradation in Escherichia coli using blue light. We demonstrate the modularity of LOVdeg by using it to tag a range of proteins, including the LacI repressor, CRISPRa activator, and the AcrB efflux pump. Additionally, we demonstrate the utility of pairing the LOVdeg tag with existing optogenetic tools to enhance performance by developing a combined EL222 and LOVdeg system. Finally, we use the LOVdeg tag in a metabolic engineering application to demonstrate post-translational control of metabolism. Together, our results highlight the modularity and functionality of the LOVdeg tag system, and introduce a powerful new tool for bacterial optogenetics.
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17
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Marchionatti E, Perreten V. Novel macrolide-lincosamide-streptogramin B resistance gene erm(56) in Trueperella pyogenes. mSphere 2023; 8:e0023923. [PMID: 37417762 PMCID: PMC10470526 DOI: 10.1128/msphere.00239-23] [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: 05/02/2023] [Accepted: 05/30/2023] [Indexed: 07/08/2023] Open
Abstract
Whole-genome sequence analysis of a macrolide, lincosamide, streptogramin B (MLSB)-resistant Trueperella pyogenes from a dog revealed a new 23S ribosomal RNA methylase gene erm(56). Expression of the cloned erm(56) confers resistance to MLSB in T. pyogenes and Escherichia coli. The erm(56) gene was flanked by two IS6100 integrated on the chromosome next to a sul1-containing class 1 integron. GenBank query revealed additional erm(56)-containing elements in another T. pyogenes and in Rothia nasimurium from livestock. IMPORTANCE A novel 23S ribosomal RNA methylase gene erm(56) flanked by insertion sequence IS6100 was identified in a Trueperella pyogenes isolated from the abscess of a dog and was also present in another T. pyogenes and in Rothia nasimurium from livestock. It was shown to confer resistance to macrolide, lincosamide, streptogramin B antibiotics in T. pyogenes and E. coli, indicating functionality in both Gram-positive and Gram-negative bacteria. The detection of erm(56) on different elements in unrelated bacteria from different animal sources and geographical origins suggests that it has been independently acquired and likely selected by the use of antibiotics in animals.
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Affiliation(s)
- Emma Marchionatti
- Division of Molecular Bacterial Epidemiology and Infectious Diseases, Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- Clinic for Ruminants, Department of Clinical Veterinary Science, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Vincent Perreten
- Division of Molecular Bacterial Epidemiology and Infectious Diseases, Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
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18
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Nazaret F, Alloing G, Mandon K, Frendo P. MarR Family Transcriptional Regulators and Their Roles in Plant-Interacting Bacteria. Microorganisms 2023; 11:1936. [PMID: 37630496 PMCID: PMC10458429 DOI: 10.3390/microorganisms11081936] [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: 06/23/2023] [Revised: 07/25/2023] [Accepted: 07/26/2023] [Indexed: 08/27/2023] Open
Abstract
The relationship between plants and associated soil microorganisms plays a major role in ecosystem functioning. Plant-bacteria interactions involve complex signaling pathways regulating various processes required by bacteria to adapt to their fluctuating environment. The establishment and maintenance of these interactions rely on the ability of the bacteria to sense and respond to biotic and abiotic environmental signals. In this context, MarR family transcriptional regulators can use these signals for transcriptional regulation, which is required to establish adapted responses. MarR-like transcriptional regulators are essential for the regulation of the specialized functions involved in plant-bacteria interactions in response to a wide range of molecules associated with the plant host. The conversion of environmental signals into changes in bacterial physiology and behavior allows the bacteria to colonize the plant and ensure a successful interaction. This review focuses on the mechanisms of plant-signal perception by MarR-like regulators, namely how they (i) allow bacteria to cope with the rhizosphere and plant endosphere, (ii) regulate the beneficial functions of Plant-Growth-Promoting Bacteria and (iii) regulate the virulence of phytopathogenic bacteria.
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Affiliation(s)
| | | | | | - Pierre Frendo
- Université Côte d’Azur, INRAE, CNRS, ISA, 06903 Sophia Antipolis, France; (F.N.); (G.A.); (K.M.)
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19
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Kato T, Okada U, Hung LW, Yamashita E, Kim HB, Kim CY, Terwilliger TC, Schweizer HP, Murakami S. Crystal structures of multidrug efflux transporters from Burkholderia pseudomallei suggest details of transport mechanism. Proc Natl Acad Sci U S A 2023; 120:e2215072120. [PMID: 37428905 PMCID: PMC10629574 DOI: 10.1073/pnas.2215072120] [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: 09/02/2022] [Accepted: 05/24/2023] [Indexed: 07/12/2023] Open
Abstract
BpeB and BpeF are multidrug efflux transporters from Burkholderia pseudomallei that enable multidrug resistance. Here, we report the crystal structures of BpeB and BpeF at 2.94 Å and 3.0 Å resolution, respectively. BpeB was found as an asymmetric trimer, consistent with the widely-accepted functional rotation mechanism for this type of transporter. One of the monomers has a distinct structure that we interpret as an intermediate along this functional cycle. Additionally, a detergent molecule bound in a previously undescribed binding site provides insights into substrate translocation through the pathway. BpeF shares structural similarities with the crystal structure of OqxB from Klebsiella pneumoniae, where both are symmetric trimers composed of three "binding"-state monomers. The structures of BpeB and BpeF further our understanding of the functional mechanisms of transporters belonging to the HAE1-RND superfamily.
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Affiliation(s)
- Takaaki Kato
- Department of Life Science and Technology, Tokyo Institute of Technology, Yokohama226-8501, Japan
| | - Ui Okada
- Department of Life Science and Technology, Tokyo Institute of Technology, Yokohama226-8501, Japan
| | - Li-Wei Hung
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM87545
| | - Eiki Yamashita
- Institute for Protein Research, Osaka University, Osaka565-0871, Japan
| | - Heung-Bok Kim
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM87545
| | - Chang-Yub Kim
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM87545
| | - Thomas C. Terwilliger
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM87545
- New Mexico Consortium, Los Alamos, NM87544
| | - Herbert P. Schweizer
- The Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ86011
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ86011
| | - Satoshi Murakami
- Department of Life Science and Technology, Tokyo Institute of Technology, Yokohama226-8501, Japan
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20
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Worley TK, Weber EA, Acott JD, Shimpi RS, Cole JM, Courcelle CT, Courcelle J. Mutations in AcrR and RNA Polymerase Confer High-Level Resistance to Psoralen-UVA Irradiation. J Bacteriol 2023; 205:e0012623. [PMID: 37249472 PMCID: PMC10294641 DOI: 10.1128/jb.00126-23] [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: 04/10/2023] [Accepted: 05/02/2023] [Indexed: 05/31/2023] Open
Abstract
DNA interstrand cross-links, such as those formed by psoralen-UVA irradiation, are highly toxic lesions in both humans and bacteria, with a single lesion being lethal in Escherichia coli. Despite the lack of effective repair, human cancers and bacteria can develop resistance to cross-linking treatments, although the mechanisms of resistance remain poorly defined. Here, we subjected E. coli to repeated psoralen-UVA exposure to isolate three independently derived strains that were >10,000-fold more resistant to this treatment than the parental strain. Analysis of these strains identified gain-of-function mutations in the transcriptional regulator AcrR and the alpha subunit of RNA polymerase that together could account for the resistance of these strains. Resistance conferred by the AcrR mutation is mediated at least in part through the regulation of the AcrAB-TolC efflux pump. Resistance via mutations in the alpha subunit of RNA polymerase occurs through a still-uncharacterized mechanism that has an additive effect with mutations in AcrR. Both acrR and rpoA mutations reduced cross-link formation in vivo. We discuss potential mechanisms in relation to the ability to repair and survive interstrand DNA cross-links. IMPORTANCE Psoralen DNA interstrand cross-links are highly toxic lesions with antimicrobial and anticancer properties. Despite the lack of effective mechanisms for repair, cells can become resistant to cross-linking agents through mechanisms that remain poorly defined. We derived resistant mutants and identified that two gain-of-function mutations in AcrR and the alpha subunit of RNA polymerase confer high levels of resistance to E. coli treated with psoralen-UVA. Resistance conferred by AcrR mutations occurs through regulation of the AcrAB-TolC efflux pump, has an additive effect with RNA polymerase mutations, acts by reducing the formation of cross-links in vivo, and reveals a novel mechanism by which these environmentally and clinically important agents are processed by the cell.
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Affiliation(s)
- Travis K. Worley
- Department of Biology, Portland State University, Portland, Oregon, USA
| | - Emma A. Weber
- Department of Biology, Portland State University, Portland, Oregon, USA
| | - Jedidiah D. Acott
- Department of Biology, Portland State University, Portland, Oregon, USA
| | - Rahul S. Shimpi
- Department of Biology, Portland State University, Portland, Oregon, USA
| | - Jessica M. Cole
- Department of Biology, Portland State University, Portland, Oregon, USA
| | | | - Justin Courcelle
- Department of Biology, Portland State University, Portland, Oregon, USA
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21
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Skalnik CJ, Cheah SY, Yang MY, Wolff MB, Spangler RK, Talman L, Morrison JH, Peirce SM, Agmon E, Covert MW. Whole-cell modeling of E. coli colonies enables quantification of single-cell heterogeneity in antibiotic responses. PLoS Comput Biol 2023; 19:e1011232. [PMID: 37327241 DOI: 10.1371/journal.pcbi.1011232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 06/01/2023] [Indexed: 06/18/2023] Open
Abstract
Antibiotic resistance poses mounting risks to human health, as current antibiotics are losing efficacy against increasingly resistant pathogenic bacteria. Of particular concern is the emergence of multidrug-resistant strains, which has been rapid among Gram-negative bacteria such as Escherichia coli. A large body of work has established that antibiotic resistance mechanisms depend on phenotypic heterogeneity, which may be mediated by stochastic expression of antibiotic resistance genes. The link between such molecular-level expression and the population levels that result is complex and multi-scale. Therefore, to better understand antibiotic resistance, what is needed are new mechanistic models that reflect single-cell phenotypic dynamics together with population-level heterogeneity, as an integrated whole. In this work, we sought to bridge single-cell and population-scale modeling by building upon our previous experience in "whole-cell" modeling, an approach which integrates mathematical and mechanistic descriptions of biological processes to recapitulate the experimentally observed behaviors of entire cells. To extend whole-cell modeling to the "whole-colony" scale, we embedded multiple instances of a whole-cell E. coli model within a model of a dynamic spatial environment, allowing us to run large, parallelized simulations on the cloud that contained all the molecular detail of the previous whole-cell model and many interactive effects of a colony growing in a shared environment. The resulting simulations were used to explore the response of E. coli to two antibiotics with different mechanisms of action, tetracycline and ampicillin, enabling us to identify sub-generationally-expressed genes, such as the beta-lactamase ampC, which contributed greatly to dramatic cellular differences in steady-state periplasmic ampicillin and was a significant factor in determining cell survival.
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Affiliation(s)
- Christopher J Skalnik
- Department of Bioengineering, Stanford University, Stanford, California, United States of America
| | - Sean Y Cheah
- Department of Bioengineering, Stanford University, Stanford, California, United States of America
| | - Mica Y Yang
- Department of Bioengineering, Stanford University, Stanford, California, United States of America
| | - Mattheus B Wolff
- Department of Bioengineering, Stanford University, Stanford, California, United States of America
| | - Ryan K Spangler
- Department of Bioengineering, Stanford University, Stanford, California, United States of America
| | - Lee Talman
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, United States of America
| | - Jerry H Morrison
- Department of Bioengineering, Stanford University, Stanford, California, United States of America
| | - Shayn M Peirce
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, United States of America
| | - Eran Agmon
- Department of Bioengineering, Stanford University, Stanford, California, United States of America
- Center for Cell Analysis and Modeling, University of Connecticut School of Medicine, Farmington, Connecticut, United States of America
| | - Markus W Covert
- Department of Bioengineering, Stanford University, Stanford, California, United States of America
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Li H, Li X, Chen T, Yang Z, Shi D, Yin J, Yang D, Zhou S, Li J, Jin M. Antidepressant exposure as a source of disinfectant resistance in waterborne bacteria. JOURNAL OF HAZARDOUS MATERIALS 2023; 452:131371. [PMID: 37030229 DOI: 10.1016/j.jhazmat.2023.131371] [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: 09/11/2022] [Revised: 03/25/2023] [Accepted: 04/03/2023] [Indexed: 05/03/2023]
Abstract
The emergence of disinfectant-resistant pathogens in water is a major threat to public health. However, whether human-consumed pharmaceuticals can induce bacterial resistance to disinfectants remains unclear. Herein, Escherichia coli was exposed to 12 antidepressants, and susceptibility of antidepressant-induced chloramphenicol (CHL)-resistant mutants to disinfectants was tested. Whole genome sequencing, global transcriptomic sequencing, and real-time quantitative polymerase chain reaction were used to elucidate the underlying mechanisms. We observed that duloxetine, fluoxetine, amitriptyline, and sertraline significantly increased the mutation frequency of E. coli against CHL by 15- to 2948-fold. The resultant mutants increased the average MIC50 of sodium hypochlorite, benzalkonium bromide, and triclosan roughly 2- to 8-fold. Consistently, marRAB and acrAB-tolC genes, together with ABC transporter genes (e.g., yddA, yadG, yojI, and mdlA), were triggered to increase the efflux of disinfectants out of the cell, while ompF was inhibited, reducing disinfectant penetration into the cell. Additionally, the occurrence of DNA mutations in marR and acrR in the mutants was observed, potentially resulting in increased synthesis of the AcrAB-TolC pump. This study indicates that pharmaceutical exposure may create disinfectant-resistant bacteria, which may then be released into water systems, providing novel insights into the potential source of water-borne disinfectant-resistant pathogens.
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Affiliation(s)
- Haibei Li
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Xinmei Li
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Tianjiao Chen
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Zhongwei Yang
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Danyang Shi
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Jing Yin
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Dong Yang
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Shuqing Zhou
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Junwen Li
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Min Jin
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China.
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Soares GG, Campanini EB, Ferreira RL, Damas MSF, Rodrigues SH, Campos LC, Galvão JD, Fuentes ASDC, Freire CCDM, Malavazi I, Pitondo-Silva A, da Cunha AF, Pranchevicius MCDS. Brevundimonas brasiliensis sp. nov.: a New Multidrug-Resistant Species Isolated from a Patient in Brazil. Microbiol Spectr 2023; 11:e0441522. [PMID: 37067439 PMCID: PMC10269605 DOI: 10.1128/spectrum.04415-22] [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: 11/03/2022] [Accepted: 02/17/2023] [Indexed: 04/18/2023] Open
Abstract
To increase knowledge on Brevundimonas pathogens, we conducted in-depth genomic and phenotypic characterization of a Brevundimonas strain isolated from the cerebrospinal fluid of a patient admitted in a neonatal intensive care unit. The strain was identified as a member of the genus Brevundimonas based on Vitek 2 system results and 16S rRNA gene sequencing and presented a multidrug resistance profile (MDR). Several molecular and biochemical tests were used to characterize and identify the species for in-depth results. The draft genome assembly of the isolate has a total length of 3,261,074 bp and a G+C of 66.86%, similar to other species of the genus. Multilocus sequence analysis, Type (Strain) Genome Server, digital DNA-DNA hybridization, and average nucleotide identity confirmed that the Brevundimonas sp. studied represents a distinct species, for which we propose the name Brevundimonas brasiliensis sp. nov. In silico analysis detected antimicrobial resistance genes (AMRGs) mediating resistance to β-lactams (penP, blaTEM-16, and blaBKC-1) and aminoglycosides [strA, strB, aac(6')-Ib, and aac(6')-Il]. We also found AMRGs encoding the AcrAB efflux pump that confers resistance to a broad spectrum of antibiotics. Colistin and quinolone resistance can be attributed to mutation in qseC and/or phoP and GyrA/GyrB, respectively. The Brevundimonas brasiliensis sp. nov. genome contained copies of type IV secretion system (T4SS)-type integrative and conjugative elements (ICEs); integrative mobilizable elements (IME); and Tn3-type and IS3, IS6, IS5, and IS1380 families, suggesting an important role in the development and dissemination of antibiotic resistance. The isolate presented a range of virulence-associated genes related to biofilm formation, adhesion, and invasion that can be relevant for its pathogenicity. Our findings provide a wealth of data to hinder the transmission of MDR Brevundimonas and highlight the need for monitoring and identifying new bacterial species in hospital environments. IMPORTANCE Brevundimonas species is considered an opportunistic human pathogen that can cause multiple types of invasive and severe infections in patients with underlying pathologies. Treatment of these pathogens has become a major challenge because many isolates are resistant to most antibiotics used in clinical practice. Furthermore, there are no consistent therapeutic results demonstrating the efficacy of antibacterial agents. Although considered a rare pathogen, recent studies have provided evidence of the emergence of Brevundimonas in clinical settings. Hence, we identified a novel pathogenic bacterium, Brevundimonas brasiliensis sp. nov., that presented a multidrug resistance (MDR) profile and carried diverse genes related to drug resistance, virulence, and mobile genetic elements. Such data can serve as a baseline for understanding the genomic diversity, adaptation, evolution, and pathogenicity of MDR Brevundimonas.
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Affiliation(s)
- Gabriela Guerrera Soares
- Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
| | - Emeline Boni Campanini
- Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
| | - Roumayne Lopes Ferreira
- Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
| | | | - Saulo Henrique Rodrigues
- Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
| | | | | | | | - Caio César de Melo Freire
- Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
| | - Iran Malavazi
- Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
| | - André Pitondo-Silva
- Programas de Pós-graduação em Odontologia e Tecnologia Ambiental, Universidade de Ribeirão Preto, Ribeirão Preto, São Paulo, Brazil
| | | | - Maria-Cristina da Silva Pranchevicius
- Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
- Centro de Ciências Biológicas e da Saúde, Biodiversidade Tropical - BIOTROP, Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
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Albicoro FJ, Vacca C, Cafiero JH, Draghi WO, Martini MC, Goulian M, Lagares A, Del Papa MF. Comparative Proteomic Analysis Revealing ActJ-Regulated Proteins in Sinorhizobium meliloti. J Proteome Res 2023; 22:1682-1694. [PMID: 37017314 PMCID: PMC10834056 DOI: 10.1021/acs.jproteome.2c00731] [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] [Indexed: 04/06/2023]
Abstract
To adapt to different environmental conditions, Sinorhizobium meliloti relies on finely tuned regulatory networks, most of which are unexplored to date. We recently demonstrated that deletion of the two-component system ActJK renders an acid-vulnerable phenotype in S. meliloti and negatively impacts bacteroid development and nodule occupancy as well. To fully understand the role of ActJ in acid tolerance, S. meliloti wild-type and S. meliloti ΔactJ proteomes were compared in the presence or absence of acid stress by nanoflow ultrahigh-performance liquid chromatography coupled to mass spectrometry. The analysis demonstrated that proteins involved in the synthesis of exopolysaccharides (EPSs) were notably enriched in ΔactJ cells in acid pH. Total EPS quantification further revealed that although EPS production was augmented at pH 5.6 in both the ΔactJ and the parental strain, the lack of ActJ significantly enhanced this difference. Moreover, several efflux pumps were found to be downregulated in the ΔactJ strain. Promoter fusion assays suggested that ActJ positively modulated its own expression in an acid medium but not at under neutral conditions. The results presented here identify several ActJ-regulated genes in S. meliloti, highlighting key components associated with ActJK regulation that will contribute to a better understanding of rhizobia adaptation to acid stress.
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Affiliation(s)
- Francisco Javier Albicoro
- Instituto de Biotecnología y Biologia Molecular -CONICET CCT La Plata - Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Carolina Vacca
- Instituto de Biotecnología y Biologia Molecular -CONICET CCT La Plata - Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Juan Hilario Cafiero
- Instituto de Biotecnología y Biologia Molecular -CONICET CCT La Plata - Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Walter Omar Draghi
- Instituto de Biotecnología y Biologia Molecular -CONICET CCT La Plata - Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - María Carla Martini
- Instituto de Biotecnología y Biologia Molecular -CONICET CCT La Plata - Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Mark Goulian
- Department of Biology, University of Pennsylvania, Philadelphia, PA. USA
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA. USA
| | - Antonio Lagares
- Instituto de Biotecnología y Biologia Molecular -CONICET CCT La Plata - Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - María Florencia Del Papa
- Instituto de Biotecnología y Biologia Molecular -CONICET CCT La Plata - Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
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25
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Huang Q, Huang Y, Li B, Li X, Guo Y, Jiang Z, Liu X, Yang Z, Ning Z, Xiao T, Jiang C, Hao L. Metagenomic analysis characterizes resistomes of an acidic, multimetal(loid)-enriched coal source mine drainage treatment system. JOURNAL OF HAZARDOUS MATERIALS 2023; 448:130898. [PMID: 36731323 DOI: 10.1016/j.jhazmat.2023.130898] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 01/07/2023] [Accepted: 01/27/2023] [Indexed: 06/18/2023]
Abstract
Heavy metal(loid) contaminations caused by mine activities are potential hot spots of antibiotic resistance genes (ARGs) because of heavy metal(loid)-induced co-selection of ARGs and heavy metal(loid) resistance genes (MRGs). This study used high-throughput metagenomic sequencing to analyze the resistome characteristics of a coal source acid mine drainage passive treatment system. The multidrug efflux mechanism dominated the antibiotic resistome, and a highly diverse heavy metal(loid) resistome was dominated by mercury-, iron-, and arsenic--associated resistance. Correlation analysis indicated that mobile gene elements had a greater influence on the dynamic of MRGs than ARGs. Among the metagenome-assembled genomes, six potential pathogens carrying multiple resistance genes resistant to several antibiotics and heavy metal(loid)s were recovered. Pseudomonas spp. contained the highest numbers of resistance genes, with resistance to two types of antibiotics and 12 types of heavy metal(loid)s. Thus, high contents of heavy metal(loid)s drove the co-selection of ARGs and MRGs. The occurrence of potential pathogens containing multiple resistance genes might increase the risk of ARG dissemination in the environment.
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Affiliation(s)
- Qiang Huang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, PR China
| | - Ye Huang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Bao Li
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Xiutong Li
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Yuan Guo
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, PR China
| | - Zhen Jiang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Xiaoling Liu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, PR China
| | - Zhenni Yang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Zengping Ning
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, PR China
| | - Tangfu Xiao
- Ministry of Education, School of Environmental Science and Engineering, Guangzhou University, Guangzhou 510006, PR China
| | - Chengying Jiang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
| | - Likai Hao
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China; CAS Center for Excellence in Quaternary Science and Global Change, Xi'an 710061, PR China.
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26
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Im H, Pearson ML, Martinez E, Cichos KH, Song X, Kruckow KL, Andrews RM, Ghanem ES, Orihuela CJ. Targeting NAD+ regeneration enhances antibiotic susceptibility of Streptococcus pneumoniae during invasive disease. PLoS Biol 2023; 21:e3002020. [PMID: 36928033 PMCID: PMC10019625 DOI: 10.1371/journal.pbio.3002020] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 02/02/2023] [Indexed: 03/18/2023] Open
Abstract
Anaerobic bacteria are responsible for half of all pulmonary infections. One such pathogen is Streptococcus pneumoniae (Spn), a leading cause of community-acquired pneumonia, bacteremia/sepsis, and meningitis. Using a panel of isogenic mutants deficient in lactate, acetyl-CoA, and ethanol fermentation, as well as pharmacological inhibition, we observed that NAD(H) redox balance during fermentation was vital for Spn energy generation, capsule production, and in vivo fitness. Redox balance disruption in fermentation pathway-specific fashion substantially enhanced susceptibility to killing in antimicrobial class-specific manner. Blocking of alcohol dehydrogenase activity with 4-methylpyrazole (fomepizole), an FDA-approved drug used as an antidote for toxic alcohol ingestion, enhanced susceptibility of multidrug-resistant Spn to erythromycin and reduced bacterial burden in the lungs of mice with pneumonia and prevented the development of invasive disease. Our results indicate fermentation enzymes are de novo targets for antibiotic development and a novel strategy to combat multidrug-resistant pathogens.
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Affiliation(s)
- Hansol Im
- Department of Microbiology, Heersink School of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Madison L. Pearson
- Department of Microbiology, Heersink School of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Eriel Martinez
- Department of Microbiology, Heersink School of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Kyle H. Cichos
- Department of Orthopaedic Surgery Arthroplasty Section, Heersink School of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Xiuhong Song
- Department of Microbiology, Heersink School of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Katherine L. Kruckow
- Department of Microbiology, Heersink School of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Rachel M. Andrews
- Department of Microbiology, Heersink School of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Elie S. Ghanem
- Department of Orthopaedic Surgery Arthroplasty Section, Heersink School of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Carlos J. Orihuela
- Department of Microbiology, Heersink School of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
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27
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RND Pump-Mediated Efflux of Amotosalen, a Compound Used in Pathogen Inactivation Technology to Enhance Safety of Blood Transfusion Products, May Compromise Its Gram-Negative Anti-Bacterial Activity. mSphere 2023; 8:e0067322. [PMID: 36853056 PMCID: PMC10117049 DOI: 10.1128/msphere.00673-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023] Open
Abstract
Pathogen inactivation is a strategy to improve the safety of transfusion products. The only pathogen reduction technology for blood products currently approved in the US utilizes a psoralen compound, called amotosalen, in combination with UVA light to inactivate bacteria, viruses, and protozoa. Psoralens have structural similarity to bacterial multidrug efflux pump substrates. As these efflux pumps are often overexpressed in multidrug-resistant pathogens, we tested whether contemporary drug-resistant pathogens might show resistance to amotosalen and other psoralens based on multidrug efflux mechanisms through genetic, biophysical, and molecular modeling analysis. The main efflux systems in Enterobacterales, Acinetobacter baumannii, and Pseudomonas aeruginosa are tripartite resistance-nodulation-cell division (RND) systems, which span the inner and outer membranes of Gram-negative pathogens, and expel antibiotics from the bacterial cytoplasm into the extracellular space. We provide evidence that amotosalen is an efflux substrate for the E. coli AcrAB, Acinetobacter baumannii AdeABC, and P. aeruginosa MexXY RND efflux pumps. Furthermore, we show that the MICs for contemporary Gram-negative bacterial isolates for these species and others in vitro approached and exceeded the concentration of amotosalen used in the approved platelet and plasma inactivation procedures. These findings suggest that otherwise safe and effective inactivation methods should be further studied to identify possible gaps in their ability to inactivate contemporary, multidrug-resistant bacterial pathogens. IMPORTANCE Pathogen inactivation is a strategy to enhance the safety of transfused blood products. We identify the compound, amotosalen, widely used for pathogen inactivation, as a bacterial multidrug efflux substrate. Specifically, experiments suggest that amotosalen is pumped out of bacteria by major efflux pumps in E. coli, Acinetobacter baumannii, and Pseudomonas aeruginosa. Such efflux pumps are often overexpressed in multidrug-resistant pathogens. Importantly, the MICs for contemporary multidrug-resistant Enterobacterales, Acinetobacter baumannii, Pseudomonas aeruginosa, Burkholderia spp., and Stenotrophomonas maltophilia isolates approached or exceeded the amotosalen concentration used in approved platelet and plasma inactivation procedures, potentially as a result of efflux pump activity. Although there are important differences in methodology between our experiments and blood product pathogen inactivation, these findings suggest that otherwise safe and effective inactivation methods should be further studied to identify possible gaps in their ability to inactivate contemporary, multidrug-resistant bacterial pathogens.
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28
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Dokla EME, Abutaleb NS, Milik SN, Kandil EAEA, Qassem OM, Elgammal Y, Nasr M, McPhillie MJ, Abouzid KAM, Seleem MN, Imming P, Adel M. SAR investigation and optimization of benzimidazole-based derivatives as antimicrobial agents against Gram-negative bacteria. Eur J Med Chem 2023; 247:115040. [PMID: 36584632 DOI: 10.1016/j.ejmech.2022.115040] [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: 09/09/2022] [Revised: 12/03/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022]
Abstract
Antibiotic-resistant bacteria represent a serious threat to modern medicine and human life. Only a minority of antibacterial agents are active against Gram-negative bacteria. Hence, the development of novel antimicrobial agents will always be a vital need. In an effort to discover new therapeutics against Gram-negative bacteria, we previously reported a structure-activity-relationship (SAR) study on 1,2-disubstituted benzimidazole derivatives. Compound III showed a potent activity against tolC-mutant Escherichia coli with an MIC value of 2 μg/mL, representing a promising lead for further optimization. Building upon this study, herein, 49 novel benzimidazole compounds were synthesized to investigate their antibacterial activity against Gram-negative bacteria. Our design focused on three main goals, to address the low permeability of our compounds and improve their cellular accumulation, to expand the SAR study to the unexplored ring C, and to optimize the lead compound (III) by modification of the methanesulfonamide moiety. Compounds (25a-d, 25f-h, 25k, 25l, 25p, 25r, 25s, and 26b) exhibited potent activity against tolC-mutant E. coli with MIC values ranging from 0.125 to 4 μg/mL, with compound 25d displaying the highest potency among the tested compounds with an MIC value of 0.125 μg/mL. As its predecessor, III, compound 25d exhibited an excellent safety profile without any significant cytotoxicity to mammalian cells. Time-kill kinetics assay indicated that 25d exhibited a bacteriostatic activity and significantly reduced E. coli JW55031 burden as compared to DMSO. Additionally, combination of 25d with colistin partially restored its antibacterial activity against Gram-negative bacterial strains (MIC values ranging from 4 to 16 μg/mL against E. coli BW25113, K. pneumoniae, A. baumannii, and P. aeruginosa). Furthermore, formulation of III and 25d as lipidic nanoparticles (nanocapsules) resulted in moderate enhancement of their antibacterial activity against Gram-negative bacterial strains (A. Baumannii, N. gonorrhoeae) and compound 25d demonstrated superior activity to the lead compound III. These findings establish compound 25d as a promising candidate for treatment of Gram-negative bacterial infections and emphasize the potential of nano-formulations in overcoming poor cellular accumulation in Gram-negative bacteria where further optimization and investigation are warranted to improve the potency and broaden the spectrum of our compounds.
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Affiliation(s)
- Eman M E Dokla
- Pharmaceutical Chemistry Department, Faculty of Pharmacy, Ain Shams University, Abbassia, Cairo, 11566, Egypt; Institute für Pharmazie, Martin-Luther-Universität Halle-Wittenberg, Wolfgang-Langenbeck-Str. 4, Halle (Saale), 06120, Germany.
| | - Nader S Abutaleb
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA; Department of Microbiology and Immunology, Zagazig University, Zagazig, 44519, Egypt
| | - Sandra N Milik
- Pharmaceutical Chemistry Department, Faculty of Pharmacy, Ain Shams University, Abbassia, Cairo, 11566, Egypt; School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Ezzat A E A Kandil
- Pharmaceutical Chemistry Department, Faculty of Pharmacy, Ain Shams University, Abbassia, Cairo, 11566, Egypt
| | - Omar M Qassem
- Pharmaceutical Chemistry Department, Faculty of Pharmacy, Ain Shams University, Abbassia, Cairo, 11566, Egypt; Purdue University Institute of Drug Discovery, Purdue University, West Lafayette, IN, 47907, USA
| | - Yehia Elgammal
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA
| | - Maha Nasr
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Ain Shams University, Abbassia, Cairo, 11566, Egypt
| | - Martin J McPhillie
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Khaled A M Abouzid
- Pharmaceutical Chemistry Department, Faculty of Pharmacy, Ain Shams University, Abbassia, Cairo, 11566, Egypt
| | - Mohamed N Seleem
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA; Center for Emerging, Zoonotic and Arthropod-borne Pathogens, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA
| | - Peter Imming
- Institute für Pharmazie, Martin-Luther-Universität Halle-Wittenberg, Wolfgang-Langenbeck-Str. 4, Halle (Saale), 06120, Germany
| | - Mai Adel
- Pharmaceutical Chemistry Department, Faculty of Pharmacy, Ain Shams University, Abbassia, Cairo, 11566, Egypt.
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29
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Holden ER, Yasir M, Turner AK, Wain J, Charles IG, Webber MA. Genome-wide analysis of genes involved in efflux function and regulation within Escherichia coli and Salmonella enterica serovar Typhimurium. MICROBIOLOGY (READING, ENGLAND) 2023; 169. [PMID: 36745554 DOI: 10.1099/mic.0.001296] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The incidence of multidrug-resistant bacteria is increasing globally, with efflux pumps being a fundamental platform limiting drug access and synergizing with other mechanisms of resistance. Increased expression of efflux pumps is a key feature of most cells that are resistant to multiple antibiotics. Whilst expression of efflux genes can confer benefits, production of complex efflux systems is energetically costly and the expression of efflux is highly regulated, with cells balancing benefits against costs. This study used TraDIS-Xpress, a genome-wide transposon mutagenesis technology, to identify genes in Escherichia coli and Salmonella Typhimurium involved in drug efflux and its regulation. We exposed mutant libraries to the canonical efflux substrate acriflavine in the presence and absence of the efflux inhibitor phenylalanine-arginine β-naphthylamide. Comparisons between conditions identified efflux-specific and drug-specific responses. Known efflux-associated genes were easily identified, including acrAB, tolC, marRA, ramRA and soxRS, confirming the specificity of the response. Further genes encoding cell envelope maintenance enzymes and products involved with stringent response activation, DNA housekeeping, respiration and glutathione biosynthesis were also identified as affecting efflux activity in both species. This demonstrates the deep relationship between efflux regulation and other cellular regulatory networks. We identified a conserved set of pathways crucial for efflux activity in these experimental conditions, which expands the list of genes known to impact on efflux efficacy. Responses in both species were similar and we propose that these common results represent a core set of genes likely to be relevant to efflux control across the Enterobacteriaceae.
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Affiliation(s)
- Emma R Holden
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, NR4 7UQ, UK
| | - Muhammad Yasir
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, NR4 7UQ, UK
| | - A Keith Turner
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, NR4 7UQ, UK
| | - John Wain
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, NR4 7UQ, UK.,Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich, Norfolk, NR4 7TJ, UK
| | - Ian G Charles
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, NR4 7UQ, UK.,Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich, Norfolk, NR4 7TJ, UK
| | - Mark A Webber
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, NR4 7UQ, UK.,Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich, Norfolk, NR4 7TJ, UK
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30
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Sharma S, Kaushik V, Kulshrestha M, Tiwari V. Different Efflux Pump Systems in Acinetobacter baumannii and Their Role in Multidrug Resistance. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023. [DOI: 10.1007/5584_2023_771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
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31
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Synthesis, antimicrobial, and antioxidant activities of disubstituted 1,2,3-triazoles with amide-hydroxyl functionality. Med Chem Res 2022. [DOI: 10.1007/s00044-022-02993-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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32
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Guo Y, Zeng C, Ma C, Cai H, Jiang X, Zhai S, Xu X, Lin M. Comparative genomics analysis of the multidrug-resistant Aeromonas hydrophila MX16A providing insights into antibiotic resistance genes. Front Cell Infect Microbiol 2022; 12:1042350. [PMID: 36405966 PMCID: PMC9669441 DOI: 10.3389/fcimb.2022.1042350] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 10/18/2022] [Indexed: 11/25/2023] Open
Abstract
In this paper, the whole genome of the multidrug-resistant Aeromonas hydrophila MX16A was comprehensively analyzed and compared after sequencing by PacBio RS II. To shed light on the drug resistance mechanism of A. hydrophila MX16A, a Kirby-Bauer disk diffusion method was used to assess the phenotypic drug susceptibility. Importantly, resistance against β-lactam, sulfonamides, rifamycins, macrolides, tetracyclines and chloramphenicols was largely consistent with the prediction analysis results of drug resistance genes in the CARD database. The varied types of resistance genes identified from A. hydrophila MX16A revealed multiple resistance mechanisms, including enzyme inactivation, gene mutation and active effusion. The publicly available complete genomes of 35 Aeromonas hydrophila strains on NCBI, including MX16A, were downloaded for genomic comparison and analysis. The analysis of 33 genomes with ANI greater than 95% showed that the pan-genome consisted of 9556 genes, and the core genes converged to 3485 genes. In summary, the obtained results showed that A. hydrophila exhibited a great genomic diversity as well as diverse metabolic function and it is believed that frequent exchanges between strains lead to the horizontal transfer of drug resistance genes.
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Affiliation(s)
- Yuxin Guo
- Fisheries College, Engineering Research Center of the Modern Technology for Eel Industry, Ministry of Education, Jimei University, Xiamen, Fujian, China
| | - Chenxi Zeng
- Fisheries College, Engineering Research Center of the Modern Technology for Eel Industry, Ministry of Education, Jimei University, Xiamen, Fujian, China
| | - Chenjie Ma
- Fisheries College, Engineering Research Center of the Modern Technology for Eel Industry, Ministry of Education, Jimei University, Xiamen, Fujian, China
| | - Hongjiao Cai
- Fisheries College, Engineering Research Center of the Modern Technology for Eel Industry, Ministry of Education, Jimei University, Xiamen, Fujian, China
| | - Xinglong Jiang
- Fisheries College, Engineering Research Center of the Modern Technology for Eel Industry, Ministry of Education, Jimei University, Xiamen, Fujian, China
| | - Shaowei Zhai
- Fisheries College, Engineering Research Center of the Modern Technology for Eel Industry, Ministry of Education, Jimei University, Xiamen, Fujian, China
| | - Xiaojin Xu
- Fisheries College, Engineering Research Center of the Modern Technology for Eel Industry, Ministry of Education, Jimei University, Xiamen, Fujian, China
| | - Mao Lin
- Fisheries College, Engineering Research Center of the Modern Technology for Eel Industry, Ministry of Education, Jimei University, Xiamen, Fujian, China
- Key Laboratory of Healthy Mariculture for the East China Sea, Ministry of Agriculture and Rural Affairs, Xiamen, Fujian, China
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Jia Y, Lu H, Zhu L. Molecular mechanism of antibiotic resistance induced by mono- and twin-chained quaternary ammonium compounds. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 832:155090. [PMID: 35398118 PMCID: PMC8985400 DOI: 10.1016/j.scitotenv.2022.155090] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/17/2022] [Accepted: 04/03/2022] [Indexed: 05/08/2023]
Abstract
The usage of quaternary ammonium compounds (QACs) as disinfectants has increased dramatically since the outbreak of COVID-19 pandemic, leading to potentially accelerated emergence of antibiotic resistance. Long-term exposure to subinhibitory level QACs can lead to multidrug resistance, but the contribution of mutagenesis to resistance evolution is obscure. In this study, we subcultured E. coli K-12 under subinhibitory (0.25 × and 0.5 × Minimum Inhibitory Concentration, MIC) or inhibitory (1 × and 2 × MIC) concentrations of benzalkonium chloride (BAC, mono-chained) or didecyldimethylammonium chloride (DDAC, twin-chained) for 60 days. The sensitivity of QAC-adapted cells to five typical antibiotics decreased significantly, and in particular, the MIC of rifampicin increased by 85 times. E. coli adapted faster to BAC but developed 20-167% higher antibiotic resistance with 56% more mutations under DDAC exposure. The broader mutations induced by QACs, including negative regulators (acrR, marR, soxR, and crp), outer membrane proteins and transporters (mipA and sbmA), and RNA polymerase (rpoB and rpoC), potentially contributed to the high multi-drug resistance. After QACs stresses were removed, the phenotypic resistance induced by subinhibitory concentrations of QACs was reversible, whereas that induced by inhibitory concentrations of QACs was irreversible. The different patterns and molecular mechanism of antibiotic resistance induced by BAC and DDAC is informative to estimating the risks of broader QACs present at varied concentrations in the environment.
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Affiliation(s)
- Yin Jia
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China
| | - Huijie Lu
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Lizhong Zhu
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China.
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Yu Z, Guo J. Non-caloric artificial sweeteners exhibit antimicrobial activity against bacteria and promote bacterial evolution of antibiotic tolerance. JOURNAL OF HAZARDOUS MATERIALS 2022; 433:128840. [PMID: 35398799 DOI: 10.1016/j.jhazmat.2022.128840] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 03/15/2022] [Accepted: 03/31/2022] [Indexed: 06/14/2023]
Abstract
Non-caloric artificial sweeteners are being widely used as safe table sugar substitutes with highly intensive sweetness but low calories. Previous studies have suggested that some of the sweeteners can alter the gut microbiota composition and promote horizontal transfer of antibiotic resistance genes across bacterial genera. However, little is known about whether these sweeteners could show antibiotic-like antimicrobial activity against bacteria, especially gut relevant bacteria. Whether they could affect evolutional trajectory of antibiotic resistance or tolerance in bacteria is also not clear yet. Here we investigated four commonly used artificial sweeteners (saccharin, sucralose, aspartame, and acesulfame potassium) against both Gram-negative (Escherichia coli and Klebsiella pneumoniae) and positive (Bacillus subtilis) strains. Results show that all four sweeteners exhibit antimicrobial effects on these strains. The antimicrobial mechanism is due to increased reactive oxygen species (ROS) and cell envelope damage. Compared to sucrose and glucose, the treatment of artificial sweeteners stimulates bacterial efflux pumps and promotes bacterial evolution of antibiotic tolerance. Collectively, our finding provides insights into roles of artificial sweeteners in the emergence of antibiotic tolerance and calls for a re-evaluation of risks due to their intensive usage.
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Affiliation(s)
- Zhigang Yu
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formly AWMC), The University of Queensland, St. Lucia, Brisbane, QLD 4072, Australia
| | - Jianhua Guo
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formly AWMC), The University of Queensland, St. Lucia, Brisbane, QLD 4072, Australia.
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Moeller AH. Metagenomic signatures of balancing selection in the human gut. Mol Ecol 2022; 32:2582-2591. [PMID: 35445474 PMCID: PMC10061541 DOI: 10.1111/mec.16474] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 03/12/2022] [Accepted: 04/12/2022] [Indexed: 11/29/2022]
Abstract
Bacterial lineages that populate the human gut microbiota contend with spatial and temporal fluctuations in numerous environmental variables, including bouts of extreme selective agents such as antibiotics. Oscillations in the adaptive landscape can impose balancing selection on populations, leaving characteristic signatures in the sequence variation of functionally significant genomic loci. Despite their potential importance for gut bacterial adaptation, the metagenomic targets of balancing selection have not been identified. Here, I present population genetic evidence that balancing selection maintains allelic diversity in multidrug efflux pumps of multiple predominant gut bacterial species. Metagenome-wide scans of 566,958 genes from 287 bacterial species represented by 118,617 metagenome-assembled genomes indicated that most genes have been conserved by purifying selection. However, dozens of core open reading frames (CORFs) displayed positive Tajima's D values that deviated significantly from their species' genomic backgrounds, indicating the action of balancing selection. Multidrug efflux pumps (MEPs) from a diversity of bacterial species were significantly enriched among the CORFs with Tajima's D values >3 in industrialized, but not nonindustrialized, human populations. The AcrB subunit of an MEP from Bacteroides dorei displayed the highest Tajima's D of any CORF. Divergent haplotypes of this CORF displayed evidence of positive selection and homology to an Escherichia coli AcrB subunit that binds tetracycline and macrolide antibiotics, suggesting functional significance and implicating medical antibiotics as an agent of selection acting on this locus. Other proteins identified as targets of balancing selection included peptidoglycan/LPS O-acetylases and ion transporters. Intriguingly, the degree of balancing selection acting on gut bacterial species was associated with species abundance in the gut based on metagenomic data, further suggesting fitness benefits of the allelic variation identified.
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Affiliation(s)
- Andrew H Moeller
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York, USA
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36
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Abstract
The recently identified proteobacterial antimicrobial compound efflux (PACE) transporters are multidrug transporters energized by the electrochemical gradient of protons. Here, we present the results of phylogenetic and functional studies on the PACE family transporter PA2880 from Pseudomonas aeruginosa. A phylogenetic analysis of the PACE family revealed that PA2880 and AceI from Acinetobacter baumannii are classified into evolutionarily distinct clades, although they both transport chlorhexidine. We demonstrate that PA2880 mainly exists as a dimer in solution, which is independent of pH, and its dimeric state is essential for its proper function. Electrogenicity studies revealed that the chlorhexidine/H+ antiport process is electrogenic. The function of several highly conserved residues was investigated. These findings provide further insights into the functional features of PACE family transporters, facilitating studies on their transport mechanisms. IMPORTANCE Pseudomonas aeruginosa is a pathogen that causes hospital-acquired (nosocomial) infections, such as ventilator-associated pneumonia and sepsis syndromes. Chlorhexidine diacetate is a disinfectant used for bacterial control in various environments potentially harboring P. aeruginosa. Therefore, investigation of the mechanism of the efflux of chlorhexidine mediated by PA2880, a PACE family transporter from P. aeruginosa, is of significance to combat bacterial infections. This study improves our understanding of the transport mechanism of PACE family transporters and will facilitate the effective utilization of chlorhexidine for P. aeruginosa control.
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Wand ME, Darby EM, Blair JMA, Sutton JM. Contribution of the efflux pump AcrAB-TolC to the tolerance of chlorhexidine and other biocides in Klebsiella spp. J Med Microbiol 2022; 71. [PMID: 35324422 PMCID: PMC9176267 DOI: 10.1099/jmm.0.001496] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Introduction. We are becoming increasingly reliant on the effectiveness of biocides to combat the spread of Gram-negative multi-drug-resistant (MDR) pathogens, including Klebsiella pneumoniae. It has been shown that chlorhexidine exposure can lead to mutations in the efflux pump repressor regulators SmvR and RamR, but the contribution of each individual efflux pump to biocide tolerance is unknown. Hypothesis. Multiple efflux pumps, including SmvA and AcrAB-TolC, are involved in increased tolerance to biocides. However, strains with upregulated AcrAB-TolC caused by biocide exposure are more problematic due to their increased MDR phenotype. Aim. To investigate the role of AcrAB-TolC in the tolerance to several biocides, including chlorhexidine, and the potential threat of cross-resistance to antibiotics through increased expression of this efflux pump. Methodology. Antimicrobial susceptibility testing was performed on K. pneumoniae isolates with ramR mutations selected for after exposure to chlorhexidine, as well as transposon mutants in components and regulators of AcrAB-TolC. RTPCR was used to detect the expression levels of this pump after biocide exposure. Strains from the globally important ST258 clade were compared for genetic differences in acrAB-TolC and its regulators and for phenotypic differences in antimicrobial susceptibility. Results. Cross-resistance to antimicrobials was observed following mutations in ramR. Exposure to chlorhexidine led to increased expression of acrA and its activator ramA, and transposon mutants in AcrAB-TolC have increased susceptibility to several biocides, including chlorhexidine. Variations in ramR within the ST258 clade led to an increase in tolerance to certain biocides, although this was strain dependent. One strain, MKP103, that had increased levels of biocide tolerance showed a unique mutation in ramR that was reflected in enhanced expression of acrA and ramA. MKP103 transposon variants were able to further enhance their tolerance to specific biocides with mutations affecting SmvA. Conclusions. Biocide tolerance in K. pneumoniae is dependent upon several components, with increased efflux through AcrAB-TolC being an important one.
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Affiliation(s)
- Matthew E Wand
- UK Health Security Agency, Research and Development, Porton Down, Salisbury, Wiltshire, SP4 0JG, UK
| | - Elizabeth M Darby
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Jessica M A Blair
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - J Mark Sutton
- UK Health Security Agency, Research and Development, Porton Down, Salisbury, Wiltshire, SP4 0JG, UK
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38
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Weldick PJ, Wang A, Halbus AF, Paunov VN. Emerging nanotechnologies for targeting antimicrobial resistance. NANOSCALE 2022; 14:4018-4041. [PMID: 35234774 DOI: 10.1039/d1nr08157h] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Antimicrobial resistance is a leading cause of mortality worldwide. Without newly approved antibiotics and antifungals being brought to the market, resistance is being developed to the ones currently available to clinicians. The reason is the applied evolutionary pressure to bacterial and fungal species due to the wide overuse of common antibiotics and antifungals in clinical practice and agriculture. Biofilms harbour antimicrobial-resistant subpopulations, which make their antimicrobial treatment even more challenging. Nanoparticle-based technologies have recently been shown to successfully overcome antimicrobial resistance in both planktonic and biofilms phenotypes. This results from the combination of novel nanomaterial research and classic antimicrobial therapies which promise to deliver a whole new generation of high-performance active nanocarrier systems. This review discusses the latest developments of promising nanotechnologies with applications against resistant pathogens and evaluates their potential and feasibility for use in novel antimicrobial therapies.
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Affiliation(s)
- Paul J Weldick
- Department of Chemistry and Biochemistry, University of Hull, Hull, HU6 7RX, UK
| | - Anheng Wang
- Department of Chemistry and Biochemistry, University of Hull, Hull, HU6 7RX, UK
| | - Ahmed F Halbus
- Department of Chemistry, College of Science, University of Babylon, Hilla, Iraq
| | - Vesselin N Paunov
- Department of Chemistry, Nazarbayev University, Kabanbay Baryr Ave. 53, Nur-sultan city, 010000, Kazakhstan.
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Shi D, Hao H, Wei Z, Yang D, Yin J, Li H, Chen Z, Yang Z, Chen T, Zhou S, Wu H, Li J, Jin M. Combined exposure to non-antibiotic pharmaceutics and antibiotics in the gut synergistically promote the development of multi-drug-resistance in Escherichia coli. Gut Microbes 2022; 14:2018901. [PMID: 35014598 PMCID: PMC8757474 DOI: 10.1080/19490976.2021.2018901] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The gut microbiota represents an important reservoir of antibiotic-resistant bacteria (ARB), which poses a significant threat to public health. However, little is known about the emergence of ARB in the gut after the combined exposure to antibiotics and non-antibiotic pharmaceutics. Here, Escherichia coli, a common opportunistic pathogen in the gut microbiota, was exposed to the antidepressant duloxetine (2.5 µg/L-25 mg/L) and/or chloramphenicol (6 µg/L-4 mg/L). The resistant strains were isolated to determine the minimum inhibition concentration (MIC) of 29 antibiotics. Then, genome-wide DNA sequencing, global transcriptomic sequencing, and real-time quantitative polymerase chain reaction were performed to quantify the synergy between duloxetine and chloramphenicol. Combined exposure synergistically increased the mutation frequency of chloramphenicol resistance by 2.45-9.01 fold compared with the independent exposure. A combination index reaching 187.7 indicated strong duloxetine and chloramphenicol synergy. The resultant mutants presented heritable enhanced resistance to 12 antibiotics and became ARB to eight antibiotics. Furthermore, combined exposure significantly increased the transcriptomic expression of acrA, acrB, and marA in E. coli, and generated a more robust oxidative stress response. Together with the occurrence of DNA mutations in marR in the mutants, stronger triggers to the AcrAB-TolC transport system and the MlaFEDB ABC transporter via reactive oxygen species (ROS)-induced mutagenesis, verified by gene knockout, contributed to the synergistic enhancement of antibiotic resistance in the combined exposure group. Regardless of whether their formation was induced by duloxetine, chloramphenicol, or their combination, the E. coli mutants showed 1.1-1.7-fold increases in the expression levels of acrA, acrB, acrZ, mdtE, and mdtF. This pattern indicated that the mutants shared the same resistance mechanisms against chloramphenicol, involving the improved efflux pumps AcrAB-TolC and mdtEF. Our findings demonstrated that antibiotics and non-antibiotic pharmaceutics synergistically accelerate the evolution of ARB and may enhance their spread.
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Affiliation(s)
- Danyang Shi
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, Tianjin, China
| | - Han Hao
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, Tianjin, China
| | - Zilin Wei
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, Tianjin, China
| | - Dong Yang
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, Tianjin, China
| | - Jing Yin
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, Tianjin, China
| | - Haibei Li
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, Tianjin, China
| | - Zhengshan Chen
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, Tianjin, China
| | - Zhongwei Yang
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, Tianjin, China
| | - Tianjiao Chen
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, Tianjin, China
| | - Shuqing Zhou
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, Tianjin, China
| | - Haiyan Wu
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, Tianjin, China
| | - Junwen Li
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, Tianjin, China
| | - Min Jin
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, Tianjin, China,CONTACT Min Jin Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, No. 1, Dali Road, Tianjin, 300050, China
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40
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Tambat R, Mahey N, Chandal N, Verma DK, Jangra M, Thakur KG, Nandanwar H. A Microbe-Derived Efflux Pump Inhibitor of the Resistance-Nodulation-Cell Division Protein Restores Antibiotic Susceptibility in Escherichia coli and Pseudomonas aeruginosa. ACS Infect Dis 2022; 8:255-270. [PMID: 35045260 DOI: 10.1021/acsinfecdis.1c00281] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The use of efflux pump inhibitors (EPIs) as potentiators along with the traditional antibiotics assists in the warfare against antibiotic-resistant superbugs. Efflux pumps of the resistance-nodulation-cell division (RND) family play crucial roles in multidrug resistance in Escherichia coli and Pseudomonas aeruginosa. Despite several efforts, clinically useful inhibitors are not available at present. This study describes ethyl 4-bromopyrrole-2-carboxylate (RP1) isolation, an inhibitor of RND transporters from the library of 4000 microbial exudates. RP1 acts synergistically with antibiotics by reducing their minimum inhibitory concentration in strains overexpressing archetype RND transporters (AcrAB-TolC and MexAB-OprM). It also improves the accumulation of Hoechst 33342 and inhibits its efflux (a hallmark of EPI functionality). The antibiotic-RP1 combinations prolong the postantibiotic effects and reduce the mutation prevention concentration of antibiotics. Additionally, from Biolayer Interferometry spectra, it appears that RP1 is bound to AcrB. RP1 displays low mammalian cytotoxicity, no Ca2+ channel inhibitory effects, and reduces the intracellular invasion of E. coli and P. aeruginosa in macrophages. Furthermore, the RP1-levofloxacin combination is nontoxic, well-tolerated, and notably effective in a murine lung infection model. In sum, RP1 is a potent EPI and worthy of further consideration as a potentiator to improve the effectiveness of existing antibiotics.
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Affiliation(s)
- Rushikesh Tambat
- Clinical Microbiology & Antimicrobial Research Laboratory, CSIR−Institute of Microbial Technology, Sector 39-A, Chandigarh 160036, India
| | - Nisha Mahey
- Clinical Microbiology & Antimicrobial Research Laboratory, CSIR−Institute of Microbial Technology, Sector 39-A, Chandigarh 160036, India
- AcSIR−Academy of Scientific & Innovative Research, Ghaziabad, Uttar Pradesh 201002, India
| | - Nishtha Chandal
- Clinical Microbiology & Antimicrobial Research Laboratory, CSIR−Institute of Microbial Technology, Sector 39-A, Chandigarh 160036, India
- AcSIR−Academy of Scientific & Innovative Research, Ghaziabad, Uttar Pradesh 201002, India
| | - Dipesh Kumar Verma
- Structural Biology Laboratory, CSIR−Institute of Microbial Technology, Sector 39-A, Chandigarh 160036, India
| | - Manoj Jangra
- Clinical Microbiology & Antimicrobial Research Laboratory, CSIR−Institute of Microbial Technology, Sector 39-A, Chandigarh 160036, India
| | - Krishan Gopal Thakur
- Structural Biology Laboratory, CSIR−Institute of Microbial Technology, Sector 39-A, Chandigarh 160036, India
| | - Hemraj Nandanwar
- Clinical Microbiology & Antimicrobial Research Laboratory, CSIR−Institute of Microbial Technology, Sector 39-A, Chandigarh 160036, India
- AcSIR−Academy of Scientific & Innovative Research, Ghaziabad, Uttar Pradesh 201002, India
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41
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Kerr R, Jabbari S, Blair JMA, Johnston IG. Dynamic Boolean modelling reveals the influence of energy supply on bacterial efflux pump expression. J R Soc Interface 2022; 19:20210771. [PMID: 35078338 PMCID: PMC8790346 DOI: 10.1098/rsif.2021.0771] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Antimicrobial resistance (AMR) is a global health issue. One key factor contributing to AMR is the ability of bacteria to export drugs through efflux pumps, which relies on the ATP-dependent expression and interaction of several controlling genes. Recent studies have shown that significant cell-to-cell ATP variability exists within clonal bacterial populations, but the contribution of intrinsic cell-to-cell ATP heterogeneity is generally overlooked in understanding efflux pumps. Here, we consider how ATP variability influences gene regulatory networks controlling expression of efflux pump genes in two bacterial species. We develop and apply a generalizable Boolean modelling framework, developed to incorporate the dependence of gene expression dynamics on available cellular energy supply. Theoretical results show that differences in energy availability can cause pronounced downstream heterogeneity in efflux gene expression. Cells with higher energy availability have a superior response to stressors. Furthermore, in the absence of stress, model bacteria develop heterogeneous pulses of efflux pump gene expression which contribute to a sustained sub-population of cells with increased efflux expression activity, potentially conferring a continuous pool of intrinsically resistant bacteria. This modelling approach thus reveals an important source of heterogeneity in cell responses to antimicrobials and sheds light on potentially targetable aspects of efflux pump-related antimicrobial resistance.
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Affiliation(s)
- Ryan Kerr
- School of Mathematics, University of Birmingham, Birmingham, UK.,Institute of Microbiology and Infection, University of Birmingham, Birmingham, UK
| | - Sara Jabbari
- School of Mathematics, University of Birmingham, Birmingham, UK.,Institute of Microbiology and Infection, University of Birmingham, Birmingham, UK
| | - Jessica M A Blair
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, UK
| | - Iain G Johnston
- Department of Mathematics, Faculty of Mathematics and Natural Sciences, University of Bergen, Bergen, Norway.,Computational Biology Unit, University of Bergen, Bergen, Norway.,CAMRIA Centre for Antimicrobial Resistance, Vestland, Norway
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42
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Ciusa ML, Marshall RL, Ricci V, Stone JW, Piddock LJV. Absence, loss-of-function, or inhibition of Escherichia coli AcrB does not increase expression of other efflux pump genes supporting the discovery of AcrB inhibitors as antibiotic adjuvants. J Antimicrob Chemother 2021; 77:633-640. [PMID: 34897478 PMCID: PMC8865010 DOI: 10.1093/jac/dkab452] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 11/11/2021] [Indexed: 11/16/2022] Open
Abstract
Objectives To determine whether expression of efflux pumps and antibiotic susceptibility are altered in Escherichia coli in response to efflux inhibition. Methods The promoter regions of nine efflux pump genes (acrAB, acrD, acrEF, emrAB, macAB, cusCFBA, mdtK, mdtABC, mdfA) were fused to gfp in pMW82 and fluorescence from each reporter construct was used as a measure of the transcriptional response to conditions in which AcrB was inhibited, absent or made non-functional. Expression was also determined by RT-qPCR. Drug susceptibility of efflux pump mutants with missense mutations known or predicted to cause loss of function of the encoded efflux pump was investigated. Results Data from the GFP reporter constructs revealed that no increased expression of the tested efflux pump genes was observed when AcrB was absent, made non-functional, or inhibited by an efflux pump inhibitor/competitive substrate, such as PAβN or chlorpromazine. This was confirmed by RT-qPCR for PAβN and chlorpromazine; however, a small but significant increase in macB gene expression was seen when acrB is deleted. Efflux inhibitors only synergized with antibiotics in the presence of a functional AcrB. When AcrB was absent or non-functional, there was no impact on MICs when other efflux pumps were also made non-functional. Conclusions Absence, loss-of-function, or inhibition of E. coli AcrB did not significantly increase expression of other efflux pump genes, which suggests there is no compensatory mechanism to overcome efflux inhibition and supports the discovery of inhibitors of AcrB as antibiotic adjuvants.
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Affiliation(s)
- Maria Laura Ciusa
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Robert L Marshall
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Vito Ricci
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Jack W Stone
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Laura J V Piddock
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
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43
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Identification of Multiple Low-Level Resistance Determinants and Coselection of Motility Impairment upon Sub-MIC Ceftriaxone Exposure in Escherichia coli. mSphere 2021; 6:e0077821. [PMID: 34787446 PMCID: PMC8597738 DOI: 10.1128/msphere.00778-21] [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] [Indexed: 11/20/2022] Open
Abstract
Resistance to third-generation cephalosporins among Gram-negative bacteria is a rapidly growing public health threat. Among the most commonly used third-generation cephalosporins is ceftriaxone. Bacterial exposure to sublethal or sub-MIC antibiotic concentrations occurs widely, from environmental residues to intermittently at the site of infection. Quality of ceftriaxone is also a concern, especially in low- and middle-income countries, with medicines having inappropriate active pharmaceutical ingredient (API) content or concentration. While focus has been largely on extended-spectrum β-lactamases and high-level resistance, there are limited data on specific chromosomal mutations and other pathways that contribute to ceftriaxone resistance under these conditions. In this work, Escherichia coli cells were exposed to a broad range of sub-MICs of ceftriaxone and mutants were analyzed using whole-genome sequencing. Low-level ceftriaxone resistance emerged after as low as 10% MIC exposure, with the frequency of resistance development increasing with concentration. Genomic analyses of mutants revealed multiple genetic bases. Mutations were enriched in genes associated with porins (envZ, ompF, ompC, and ompR), efflux regulation (marR), and the outer membrane and metabolism (galU and pgm), but none were associated with the ampC β-lactamase. We also observed selection of mgrB mutations. Notably, pleiotropic effects on motility and cell surface were selected for in multiple independent genes, which may have important consequences. Swift low-level resistance development after exposure to low ceftriaxone concentrations may result in reservoirs of bacteria with relevant mutations for survival and increased resistance. Thus, initiatives for broader surveillance of low-level antibiotic resistance and genomic resistance determinants should be pursued when resources are available. IMPORTANCE Ceftriaxone is a widely consumed antibiotic used to treat bacterial infections. Bacteria, however, are increasingly becoming resistant to ceftriaxone. Most work has focused on known mechanisms associated with high-level ceftriaxone resistance. However, bacteria are extensively exposed to low antibiotic concentrations, and there are limited data on the evolution of ceftriaxone resistance under these conditions. In this work, we observed that bacteria quickly developed low-level resistance due to both novel and previously described mutations in multiple different genes upon exposure to low ceftriaxone concentrations. Additionally, exposure also led to changes in motility and the cell surface, which can impact other processes associated with resistance and infection. Notably, low-level-resistant bacteria would be missed in the clinic, which uses set breakpoints. While they may require increased resources, this work supports continued initiatives for broader surveillance of low-level antibiotic resistance or their resistance determinants, which can serve as predictors of higher risk for clinical resistance.
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Zaknoon F, Meir O, Mor A. Mechanistic Studies of Antibiotic Adjuvants Reducing Kidney's Bacterial Loads upon Systemic Monotherapy. Pharmaceutics 2021; 13:pharmaceutics13111947. [PMID: 34834362 PMCID: PMC8621570 DOI: 10.3390/pharmaceutics13111947] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Revised: 11/11/2021] [Accepted: 11/14/2021] [Indexed: 12/01/2022] Open
Abstract
We describe the design and attributes of a linear pentapeptide-like derivative (C14(ω5)OOc10O) screened for its ability to elicit bactericidal competences of plasma constituents against Gram-negative bacteria (GNB). In simpler culture media, the lipopeptide revealed high aptitudes to sensitize resilient GNB to hydrophobic and/or efflux-substrate antibiotics, whereas in their absence, C14(ω5)OOc10O only briefly delayed bacterial proliferation. Instead, at low micromolar concentrations, the lipopeptide has rapidly lowered bacterial proton and ATP levels, although significantly less than upon treatment with its bactericidal analog. Mechanistic studies support a two-step scenario providing a plausible explanation for the lipopeptide’s biological outcomes against GNB: initially, C14(ω5)OOc10O permeabilizes the outer membrane similarly to polymyxin B, albeit in a manner not necessitating as much LPS-binding affinity. Subsequently, C14(ω5)OOc10O would interact with the inner membrane gently yet intensively enough to restrain membrane-protein functions such as drug efflux and/or ATP generation, while averting the harsher inner membrane perturbations that mediate the fatal outcome associated with bactericidal peers. Preliminary in vivo studies where skin wound infections were introduced in mice, revealed a significant efficacy in affecting bacterial viability upon topical treatment with creams containing C14(ω5)OOc10O, whereas synergistic combination therapies were able to secure the pathogen’s eradication. Further, capitalizing on the finding that C14(ω5)OOc10O plasma-potentiating concentrations were attainable in mice blood at sub-maximal tolerated doses, we used a urinary tract infection model to acquire evidence for the lipopeptide’s systemic capacity to reduce the kidney’s bacterial loads. Collectively, the data establish the role of C14(ω5)OOc10O as a compelling antibacterial potentiator and suggest its drug-like potential.
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Identified Seaweed Compound Diphenylmethane Serves as an Efflux Pump Inhibitor in Drug-Resistant Escherichia coli. Antibiotics (Basel) 2021; 10:antibiotics10111378. [PMID: 34827316 PMCID: PMC8614644 DOI: 10.3390/antibiotics10111378] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 11/06/2021] [Accepted: 11/09/2021] [Indexed: 11/17/2022] Open
Abstract
Drug efflux pumps are one of the major elements used by antibiotic-resistant bacteria. Efflux pump inhibitors (EPIs) are potential therapeutic agents for adjunctive therapy, which can restore the activity of antibiotics that are no longer effective against pathogens. This study evaluated the seaweed compound diphenylmethane (DPM) for its EPI activity. The IC50 and modulation results showed that DPM has no antibacterial activity but can potentiate the activity of antibiotics against drug-resistant E. coli. Time-kill studies reported that a combination of DPM and erythromycin exhibited greater inhibitory activity against drug-resistant Escherichia coli. Dye accumulation and dye efflux studies using Hoechst 33342 and ethidium bromide showed that the addition of DPM significantly increased dye accumulation and reduced dye efflux in drug-resistant E. coli, suggesting its interference with dye translocation by an efflux pump. Using MALDI-TOF, it was observed that the addition of DPM could continuously reduce antibiotic efflux in drug-resistant E. coli. Additionally, DPM did not seem to damage the E. coli membranes, and the cell toxicity test showed that it features mild human-cell toxicity. In conclusion, these findings showed that DPM could serve as a potential EPI for drug-resistant E. coli.
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Rodrigues GL, Matteoli FP, Gazara RK, Rodrigues PSL, Dos Santos ST, Alves AF, Pedrosa-Silva F, Oliveira-Pinheiro I, Canedo-Alvarenga D, Olivares FL, Venancio TM. Characterization of cellular, biochemical and genomic features of the diazotrophic plant growth-promoting bacterium Azospirillum sp. UENF-412522, a novel member of the Azospirillum genus. Microbiol Res 2021; 254:126896. [PMID: 34715447 DOI: 10.1016/j.micres.2021.126896] [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: 05/07/2021] [Revised: 08/11/2021] [Accepted: 10/14/2021] [Indexed: 11/19/2022]
Abstract
Given their remarkable beneficial effects on plant growth, several Azospirillum isolates currently integrate the formulations of various commercial inoculants. Our research group isolated a new strain, Azospirillum sp. UENF-412522, from passion fruit rhizoplane. This isolate uses carbon sources that are partially distinct from closely-related Azospirillum isolates. Scanning electron microscopy analysis and population counts demonstrate the ability of Azospirillum sp. UENF-412522 to colonize the surface of passion fruit roots. In vitro assays demonstrate the ability of Azospirillum sp. UENF-412522 to fix atmospheric nitrogen, to solubilize phosphate and to produce indole-acetic acid. Passion fruit plantlets inoculated with Azospirillum sp. UENF-41255 showed increased shoot and root fresh matter by 13,8% and 88,6% respectively, as well as root dry matter by 61,4%, further highlighting its biotechnological potential for agriculture. We sequenced the genome of Azospirillum sp. UENF-412522 to investigate the genetic basis of its plant-growth promotion properties. We identified the key nif genes for nitrogen fixation, the complete PQQ operon for phosphate solubilization, the acdS gene that alleviates ethylene effects on plant growth, and the napCAB operon, which produces nitrite under anoxic conditions. We also found several genes conferring resistance to common soil antibiotics, which are critical for Azospirillum sp. UENF-412522 survival in the rhizosphere. Finally, we also assessed the Azospirillum pangenome and highlighted key genes involved in plant growth promotion. A phylogenetic reconstruction of the genus was also conducted. Our results support Azospirillum sp. UENF-412522 as a good candidate for bioinoculant formulations focused on plant growth promotion in sustainable systems.
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Affiliation(s)
- Gustavo L Rodrigues
- Laboratório de Química e Função de Proteínas e Peptídeos, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Brazil
| | - Filipe P Matteoli
- Laboratório de Química e Função de Proteínas e Peptídeos, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Brazil
| | - Rajesh K Gazara
- Laboratório de Química e Função de Proteínas e Peptídeos, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Brazil
| | | | - Samuel T Dos Santos
- Núcleo de Desenvolvimento de Insumos Biológicos para a Agricultura (NUDIBA), UENF, Brazil
| | - Alice F Alves
- Núcleo de Desenvolvimento de Insumos Biológicos para a Agricultura (NUDIBA), UENF, Brazil; Laboratório de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, UENF, Brazil
| | - Francisnei Pedrosa-Silva
- Laboratório de Química e Função de Proteínas e Peptídeos, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Brazil
| | - Isabella Oliveira-Pinheiro
- Laboratório de Química e Função de Proteínas e Peptídeos, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Brazil
| | - Daniella Canedo-Alvarenga
- Laboratório de Química e Função de Proteínas e Peptídeos, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Brazil
| | - Fabio L Olivares
- Núcleo de Desenvolvimento de Insumos Biológicos para a Agricultura (NUDIBA), UENF, Brazil; Laboratório de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, UENF, Brazil.
| | - Thiago M Venancio
- Laboratório de Química e Função de Proteínas e Peptídeos, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Brazil.
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Hwang J, Park SH, Lee CW, Do H, Shin SC, Kim HW, Lee SG, Park HH, Kwon S, Lee JH. Crystal structure of a MarR family protein from the psychrophilic bacterium Paenisporosarcina sp. TG-14 in complex with a lipid-like molecule. IUCRJ 2021; 8:842-852. [PMID: 34584745 PMCID: PMC8420766 DOI: 10.1107/s2052252521005704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 06/02/2021] [Indexed: 06/13/2023]
Abstract
MarR family proteins regulate the transcription of multiple antibiotic-resistance genes and are widely found in bacteria and archaea. Recently, a new MarR family gene was identified by genome analysis of the psychrophilic bacterium Paenisporosarcina sp. TG-14, which was isolated from sediment-laden basal ice in Antarctica. In this study, the crystal structure of the MarR protein from Paenisporosarcina sp. TG-14 (PaMarR) was determined at 1.6 Å resolution. In the crystal structure, a novel lipid-type compound (palmitic acid) was found in a deep cavity, which was assumed to be an effector-binding site. Comparative structural analysis of homologous MarR family proteins from a mesophile and a hyperthermophile showed that the DNA-binding domain of PaMarR exhibited relatively high mobility, with a disordered region between the β1 and β2 strands. In addition, structural comparison with other homologous complex structures suggests that this structure constitutes a conformer transformed by palmitic acid. Biochemical analysis also demonstrated that PaMarR binds to cognate DNA, where PaMarR is known to recognize two putative binding sites depending on its molar concentration, indicating that PaMarR binds to its cognate DNA in a stoichiometric manner. The present study provides structural information on the cold-adaptive MarR protein with an aliphatic compound as its putative effector, extending the scope of MarR family protein research.
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Affiliation(s)
- Jisub Hwang
- Research Unit of Cryogenic Novel Material, Korea Polar Research Institute, Incheon 21990, Republic of Korea
- Department of Polar Sciences, University of Science and Technology, Incheon 21990, Republic of Korea
| | - Sun-Ha Park
- Research Unit of Cryogenic Novel Material, Korea Polar Research Institute, Incheon 21990, Republic of Korea
| | - Chang Woo Lee
- Research Unit of Cryogenic Novel Material, Korea Polar Research Institute, Incheon 21990, Republic of Korea
| | - Hackwon Do
- Research Unit of Cryogenic Novel Material, Korea Polar Research Institute, Incheon 21990, Republic of Korea
| | - Seung Chul Shin
- Division of Life Sciences, Korea Polar Research Institute, Incheon 21990, Republic of Korea
| | - Han-Woo Kim
- Research Unit of Cryogenic Novel Material, Korea Polar Research Institute, Incheon 21990, Republic of Korea
- Department of Polar Sciences, University of Science and Technology, Incheon 21990, Republic of Korea
| | - Sung Gu Lee
- Research Unit of Cryogenic Novel Material, Korea Polar Research Institute, Incheon 21990, Republic of Korea
- Department of Polar Sciences, University of Science and Technology, Incheon 21990, Republic of Korea
| | - Hyun Ho Park
- College of Pharmacy, Chung-Ang University, Dongjak-gu, Seoul 06974, Republic of Korea
| | - Sunghark Kwon
- Department of Biotechnology, Konkuk University, Chungju, Chungbuk 27478, Republic of Korea
| | - Jun Hyuck Lee
- Research Unit of Cryogenic Novel Material, Korea Polar Research Institute, Incheon 21990, Republic of Korea
- Department of Polar Sciences, University of Science and Technology, Incheon 21990, Republic of Korea
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Jahn LJ, Simon D, Jensen M, Bradshaw C, Ellabaan MMH, Sommer MOA. Compatibility of Evolutionary Responses to Constituent Antibiotics Drive Resistance Evolution to Drug Pairs. Mol Biol Evol 2021; 38:2057-2069. [PMID: 33480997 PMCID: PMC8097295 DOI: 10.1093/molbev/msab006] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Antibiotic combinations are considered a relevant strategy to tackle the global antibiotic resistance crisis since they are believed to increase treatment efficacy and reduce resistance evolution (WHO treatment guidelines for drug-resistant tuberculosis: 2016 update.). However, studies of the evolution of bacterial resistance to combination therapy have focused on a limited number of drugs and have provided contradictory results (Lipsitch, Levin BR. 1997; Hegreness et al. 2008; Munck et al. 2014). To address this gap in our understanding, we performed a large-scale laboratory evolution experiment, adapting eight replicate lineages of Escherichia coli to a diverse set of 22 different antibiotics and 33 antibiotic pairs. We found that combination therapy significantly limits the evolution of de novode novo resistance in E. coli, yet different drug combinations vary substantially in their propensity to select for resistance. In contrast to current theories, the phenotypic features of drug pairs are weak predictors of resistance evolution. Instead, the resistance evolution is driven by the relationship between the evolutionary trajectories that lead to resistance to a drug combination and those that lead to resistance to the component drugs. Drug combinations requiring a novel genetic response from target bacteria compared with the individual component drugs significantly reduce resistance evolution. These data support combination therapy as a treatment option to decelerate resistance evolution and provide a novel framework for selecting optimized drug combinations based on bacterial evolutionary responses.
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Affiliation(s)
- Leonie Johanna Jahn
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Daniel Simon
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Mia Jensen
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Charles Bradshaw
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
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Kunjapur AM, Napolitano MG, Hysolli E, Noguera K, Appleton EM, Schubert MG, Jones MA, Iyer S, Mandell DJ, Church GM. Synthetic auxotrophy remains stable after continuous evolution and in coculture with mammalian cells. SCIENCE ADVANCES 2021; 7:eabf5851. [PMID: 34215581 PMCID: PMC11060021 DOI: 10.1126/sciadv.abf5851] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 05/18/2021] [Indexed: 06/13/2023]
Abstract
Understanding the evolutionary stability and possible context dependence of biological containment techniques is critical as engineered microbes are increasingly under consideration for applications beyond biomanufacturing. While synthetic auxotrophy previously prevented Escherichia coli from exhibiting detectable escape from batch cultures, its long-term effectiveness is unknown. Here, we report automated continuous evolution of a synthetic auxotroph while supplying a decreasing concentration of essential biphenylalanine (BipA). After 100 days of evolution, triplicate populations exhibit no observable escape and exhibit normal growth rates at 10-fold lower BipA concentration than the ancestral synthetic auxotroph. Allelic reconstruction reveals the contribution of three genes to increased fitness at low BipA concentrations. Based on its evolutionary stability, we introduce the progenitor strain directly to mammalian cell culture and observe containment of bacteria without detrimental effects on HEK293T cells. Overall, our findings reveal that synthetic auxotrophy is effective on time scales and in contexts that enable diverse applications.
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Affiliation(s)
- Aditya M Kunjapur
- Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, NRB 238, Boston, MA 02115, USA.
- Department of Chemical and Biomolecular Engineering, University of Delaware, 150 Academy Street, CLB 215, Newark, DE 19716, USA
| | - Michael G Napolitano
- Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, NRB 238, Boston, MA 02115, USA
| | - Eriona Hysolli
- Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, NRB 238, Boston, MA 02115, USA
| | - Karen Noguera
- Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, NRB 238, Boston, MA 02115, USA
| | - Evan M Appleton
- Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, NRB 238, Boston, MA 02115, USA
| | - Max G Schubert
- Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, NRB 238, Boston, MA 02115, USA
| | - Michaela A Jones
- Department of Chemical and Biomolecular Engineering, University of Delaware, 150 Academy Street, CLB 215, Newark, DE 19716, USA
| | - Siddharth Iyer
- Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, NRB 238, Boston, MA 02115, USA
| | - Daniel J Mandell
- Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, NRB 238, Boston, MA 02115, USA
| | - George M Church
- Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, NRB 238, Boston, MA 02115, USA.
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Tam HK, Foong WE, Oswald C, Herrmann A, Zeng H, Pos KM. Allosteric drug transport mechanism of multidrug transporter AcrB. Nat Commun 2021; 12:3889. [PMID: 34188038 PMCID: PMC8242077 DOI: 10.1038/s41467-021-24151-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 06/02/2021] [Indexed: 12/27/2022] Open
Abstract
Gram-negative bacteria maintain an intrinsic resistance mechanism against entry of noxious compounds by utilizing highly efficient efflux pumps. The E. coli AcrAB-TolC drug efflux pump contains the inner membrane H+/drug antiporter AcrB comprising three functionally interdependent protomers, cycling consecutively through the loose (L), tight (T) and open (O) state during cooperative catalysis. Here, we present 13 X-ray structures of AcrB in intermediate states of the transport cycle. Structure-based mutational analysis combined with drug susceptibility assays indicate that drugs are guided through dedicated transport channels toward the drug binding pockets. A co-structure obtained in the combined presence of erythromycin, linezolid, oxacillin and fusidic acid shows binding of fusidic acid deeply inside the T protomer transmembrane domain. Thiol cross-link substrate protection assays indicate that this transmembrane domain-binding site can also accommodate oxacillin or novobiocin but not erythromycin or linezolid. AcrB-mediated drug transport is suggested to be allosterically modulated in presence of multiple drugs. Gram-negative bacteria can display intrinsic antibiotic resistance due to the action of tripartite efflux pumps, which include a H+/drug antiporter component. Here, the authors present a structure-function analysis of antiporter AcrB in intermediate states of the transport cycle, showing novel drug-binding sites and transport pathways.
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Affiliation(s)
- Heng-Keat Tam
- Institute of Biochemistry, Goethe-University Frankfurt, Frankfurt am Main, Germany. .,Hengyang Medical College, University of South China, Hengyang, Hunan Province, China.
| | - Wuen Ee Foong
- Institute of Biochemistry, Goethe-University Frankfurt, Frankfurt am Main, Germany
| | - Christine Oswald
- Institute of Biochemistry, Goethe-University Frankfurt, Frankfurt am Main, Germany.,Sosei Heptares, Steinmetz Building, Granta Park, Great Abington, Cambridge, UK
| | - Andrea Herrmann
- Institute of Biochemistry, Goethe-University Frankfurt, Frankfurt am Main, Germany
| | - Hui Zeng
- Institute of Biochemistry, Goethe-University Frankfurt, Frankfurt am Main, Germany
| | - Klaas M Pos
- Institute of Biochemistry, Goethe-University Frankfurt, Frankfurt am Main, Germany.
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