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de Lima FCG, de Araújo AR, do Nascimento AV, Bezerra Cavalcanti CDL, Oliveira Júnior JB, Sandes JM, da Silva EM, de Freitas CF, Veras DL, Alves LC, Brayner FA. In vitro evaluation of human intravenous immunoglobulin in combination with antimicrobials and human serum against multidrug-resistant isolates of Acinetobacter baumannii. Braz J Microbiol 2023; 54:2845-2856. [PMID: 37904004 PMCID: PMC10689330 DOI: 10.1007/s42770-023-01153-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 10/12/2023] [Indexed: 11/01/2023] Open
Abstract
The high incidence of multidrug-resistant (MDR) Acinetobacter baumannii has been a challenge for health worldwide, due to the reduction of therapeutic options, making the use of antimicrobial combinations necessary for the treatment, such as meropenem, amikacin, and colistin. Antibodies against bacterial species, mainly immunoglobulins G (IgG), are produced for acting as effector mechanisms (neutralization, opsonization, phagocytosis, and complement system activation). Some studies have demonstrated promising results of IgG in combination with antimicrobial preparations against bacterial infections, in which the direct action of IgG has restored the immune system balance. Serious problem caused by the increase of MDR A. baumannii isolates results in a constant search for therapeutic alternatives to defeat these infections. However, this study aims to verify in vitro the phagocytosis rate of the A. baumannii-infected human monocytes, as well as to analyze possible morphological changes induced by intravenous immunoglobulin G (IVIG) with human serum in association with antimicrobials. The phagocytosis rate and bacterial cell binding capacity of IVIG were determined for two A. baumannii isolates submitted to 4 mg/mL of human IVIG alone and in combination with different sub-minimum inhibitory concentrations (sub-MICs) of meropenem, amikacin, and colistin and processed for indirect immunofluorescence. Subsequently, these isolates were resubmitted and coupled with human serum and processed for scanning electron microscopy. There was no statistical difference for phagocytosis rates in the isolates tested. Bacterial isolates showed alterations in cell morphology when exposed to IVIG/human serum alone and in combination with antimicrobials such as alteration in shape, wrinkling, membrane depression, and especially cell rupture with extravasation of cytoplasmic material. The isolates visually differed in the IVIG binding to the bacterial cell, with higher fluorescence intensity, which corresponds to the highest IVIG binding, in the isolate more sensitive to meropenem, amikacin, and colistin. No differences between treatments were observed in the IVIG binding to the bacterial cell. The combined action of IVIG with meropenem, amikacin, and colistin against A. baumannii MDR isolates induced several bacterial cell damages. And when associated with human serum, a massive destruction of cells can be observed. These results may suggest the analysis of the use of IgG preparations for the treatment of A. baumannii MDR infections.
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Affiliation(s)
| | - Alberon Ribeiro de Araújo
- Laboratory of Molecular and Cellular Biology, and Laboratory of Leishmaniasis and Mutagenesis, Department of Parasitology, Aggeu Magalhães Institute (FIOCRUZ/PE), Recife, Pernambuco, Brazil
| | | | | | - Jorge Belém Oliveira Júnior
- Laboratory of Molecular and Cellular Biology, and Laboratory of Leishmaniasis and Mutagenesis, Department of Parasitology, Aggeu Magalhães Institute (FIOCRUZ/PE), Recife, Pernambuco, Brazil.
| | - Jana Messias Sandes
- Electronic Microscopy Laboratory, Keizo Asami Institute, Federal Universidad of Pernambuco, Recife, Pernambuco, Brazil
| | - Everton Morais da Silva
- Bachelor's Degree in Pharmacy From Federal Universidad of Pernambuco, Recife, Pernambuco, Brazil
| | | | - Dyana Leal Veras
- Laboratory of Molecular and Cellular Biology, and Laboratory of Leishmaniasis and Mutagenesis, Department of Parasitology, Aggeu Magalhães Institute (FIOCRUZ/PE), Recife, Pernambuco, Brazil
| | - Luis Carlos Alves
- Laboratory of Molecular and Cellular Biology, and Laboratory of Leishmaniasis and Mutagenesis, Department of Parasitology, Aggeu Magalhães Institute (FIOCRUZ/PE), Recife, Pernambuco, Brazil
- Electronic Microscopy Laboratory, Keizo Asami Institute, Federal Universidad of Pernambuco, Recife, Pernambuco, Brazil
| | - Fábio André Brayner
- Laboratory of Molecular and Cellular Biology, and Laboratory of Leishmaniasis and Mutagenesis, Department of Parasitology, Aggeu Magalhães Institute (FIOCRUZ/PE), Recife, Pernambuco, Brazil
- Electronic Microscopy Laboratory, Keizo Asami Institute, Federal Universidad of Pernambuco, Recife, Pernambuco, Brazil
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de Oliveira ÉM, Beltrão EMB, Pimentel MIS, Lopes ACDS. Occurrence of high-risk clones of Klebsiella pneumoniae ST11, ST340, and ST855 carrying the blaKPC-2, blaNDM-1, blaNDM-5, and blaNDM-7 genes from colonized and infected patients in Brazil. J Appl Microbiol 2023; 134:lxad242. [PMID: 37880999 DOI: 10.1093/jambio/lxad242] [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: 08/16/2023] [Revised: 09/28/2023] [Accepted: 10/24/2023] [Indexed: 10/27/2023]
Abstract
AIMS Determine which sequence type (ST) clones were carrying the blaKPC, blaNDM, blaVIM, blaIMP, and blaGES genes and their variants in clinical isolates of multidrug-resistant Klebsiella pneumoniae. METHODS AND RESULTS Ten K. pneumoniae isolates were obtained from the colonized and infected patients in a public hospital in the city of Recife-PE, in northeastern Brazil, and were further analyzed. The detection of carbapenem resistance genes and the seven housekeeping genes [for multilocus sequence typing (MLST) detection] were done with PCR and sequencing. The blaKPC and blaNDM genes were detected concomitantly in all isolates, with variants being detected blaNDM-1, blaNDM-5, blaNDM-7, and blaKPC-2. The blaKPC-2 and blaNDM-1 combination being the most frequent. Molecular typing by MLST detected three types of high-risk ST clones, associated with the clonal complex 258, ST11/CC258 in eight isolates, and ST855/CC258 and ST340/CC258 in the other two isolates. CONCLUSIONS These findings are worrying, as they have a negative impact on the scenario of antimicrobial resistance, and show the high genetic variability of K. pneumoniae and its ability to mutate resistance genes and risk of dissemination via different ST clones.
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Affiliation(s)
- Érica Maria de Oliveira
- Departamento de Medicina Tropical, Universidade Federal de Pernambuco-UFPE, Recife, PE 50732-970, Brazil
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Posada V, Espejo BF, Orduz S. De novo design of short antimicrobial lipopeptides. AN ACAD BRAS CIENC 2021; 93:e20210362. [PMID: 34817038 DOI: 10.1590/0001-3765202120210362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 08/05/2021] [Indexed: 11/21/2022] Open
Abstract
The increase in bacterial resistance to antibiotics available leads to the search for new compounds with antimicrobial potential, such as peptides and lipopeptides. In this work, eight short lipopeptides with the structural pattern Cn-X1 X2 X3-NH2 were de novo designed, synthesized by Fmoc solid phase and characterized by instrumental techniques. The results of the in vitro tests indicated that two of them, LIP 4 and LIP 12 display antibacterial activity against 4 pathogenic bacteria with minimum inhibitory concentrations (MIC) between 9.50 and 100 μM and between 8.50 and 10.0 μM, respectively; they did not displayed toxicity to human erythrocytes at concentrations between 3.13 and 50.0 μM. The antibacterial mechanism of action observed by scanning electron microscopy indicate that the cell membrane was the target, causing the formation of blisters and vesicles, with size ranging from 100 to 120 nm. The lipopeptide LIP 12, with higher activity, was stable to proteases of human blood serum.
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Affiliation(s)
- Vanessa Posada
- Universidad Nacional de Colombia, Sede Medellin, Escuela de Química, Facultad de Ciencias, Carrera 65, No. 59A - 110, 050034, Medellin, Colombia
| | - Blanca Fabiola Espejo
- Universidad Nacional de Colombia, Sede Medellin, Escuela de Química, Facultad de Ciencias, Carrera 65, No. 59A - 110, 050034, Medellin, Colombia
| | - Sergio Orduz
- Universidad Nacional de Colombia, Sede Medellin, Escuela de Biociencias, Facultad de Ciencias, Carrera 65, No. 59A - 110, 050034, Medellin, Colombia
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Goode A, Yeh V, Bonev BB. Interactions of polymyxin B with lipopolysaccharide-containing membranes. Faraday Discuss 2021; 232:317-329. [PMID: 34550139 PMCID: PMC8704168 DOI: 10.1039/d1fd00036e] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Bacterial resistance to antibiotics constantly remodels the battlefront between infections and antibiotic therapy. Polymyxin B, a cationic peptide with an anti-Gram-negative spectrum of activity is re-entering use as a last resort measure and as an adjuvant. We use fluorescence dequenching to investigate the role of the rough chemotype bacterial lipopolysaccharide from E. coli BL21 as a molecular facilitator of membrane disruption by LPS. The minimal polymyxin B/lipid ratio required for leakage onset increased from 5.9 × 10−4 to 1.9 × 10−7 in the presence of rLPS. We confirm polymyxin B activity against E. coli BL21 by the agar diffusion method and determined a MIC of 291 μg ml−1. Changes in lipid membrane stability and dynamics in response to polymyxin and the role of LPS are investigated by 31P NMR and high resolution 31P MAS NMR relaxation is used to monitor selective molecular interactions between polymyxin B and rLPS within bilayer lipid membranes. We observe a strong facilitating effect from rLPS on the membrane lytic properties of polymyxin B and a specific, pyrophosphate-mediated process of molecular recognition of LPS by polymyxin B. Polymyxin B uses bacterial LPS as docking receptor to cross the outer membrane.![]()
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Affiliation(s)
- Alice Goode
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, NG7 2UH, UK.
| | - Vivien Yeh
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, NG7 2UH, UK.
| | - Boyan B Bonev
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, NG7 2UH, UK.
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Rodríguez-Santiago J, Cornejo-Juárez P, Silva-Sánchez J, Garza-Ramos U. Polymyxin resistance in Enterobacterales: overview and epidemiology in the Americas. Int J Antimicrob Agents 2021; 58:106426. [PMID: 34419579 DOI: 10.1016/j.ijantimicag.2021.106426] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 08/07/2021] [Accepted: 08/15/2021] [Indexed: 12/30/2022]
Abstract
The worldwide spread of carbapenem- and polymyxin-resistant Enterobacterales represents an urgent public-health threat. However, for most countries in the Americas, the available data are limited, although Latin America has been suggested as a silent spreading reservoir for isolates carrying plasmid-mediated polymyxin resistance mechanisms. This work provides an overall update on polymyxin and polymyxin resistance and focuses on uses, availability and susceptibility testing. Moreover, a comprehensive review of the current polymyxin resistance epidemiology in the Americas is provided. We found that reports in the English and Spanish literature show widespread carbapenemase-producing and colistin-resistant Klebsiella pneumoniae in the Americas determined by the clonal expansion of the pandemic clone ST258 and mgrB-mediated colistin resistance. In addition, widespread IncI2 and IncX4 plasmids carrying mcr-1 in Escherichia coli come mainly from human sources; however, plasmid-mediated colistin resistance in the Americas is underreported in the veterinary sector. These findings demonstrate the urgent need for the implementation of polymyxin resistance surveillance in Enterobacterales as well as appropriate regulatory measures for antimicrobial use in veterinary medicine.
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Affiliation(s)
- J Rodríguez-Santiago
- Instituto Nacional de Salud Pública (INSP), Centro de Investigación sobre Enfermedades Infecciosas (CISEI), Laboratorio de Resistencia Bacteriana, Cuernavaca, Morelos, México; Programa de Doctorado en Ciencias Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México, México
| | - P Cornejo-Juárez
- Departamento de Infectología, Instituto Nacional de Cancerología (INCan), Ciudad de México, México
| | - J Silva-Sánchez
- Instituto Nacional de Salud Pública (INSP), Centro de Investigación sobre Enfermedades Infecciosas (CISEI), Laboratorio de Resistencia Bacteriana, Cuernavaca, Morelos, México
| | - U Garza-Ramos
- Instituto Nacional de Salud Pública (INSP), Centro de Investigación sobre Enfermedades Infecciosas (CISEI), Laboratorio de Resistencia Bacteriana, Cuernavaca, Morelos, México.
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Oliveira ÉMD, Beltrão EMB, Scavuzzi AML, Barros JF, Lopes ACS. High plasmid variability, and the presence of IncFIB, IncQ, IncA/C, IncHI1B, and IncL/M in clinical isolates of Klebsiella pneumoniae with bla KPC and bla NDM from patients at a public hospital in Brazil. Rev Soc Bras Med Trop 2020; 53:e20200397. [PMID: 33111914 PMCID: PMC7580274 DOI: 10.1590/0037-8682-0397-2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 08/05/2020] [Indexed: 12/15/2022] Open
Abstract
INTRODUCTION Antibiotic resistance in carbapenemase-producing Klebsiella
pneumoniae is acquired and disseminated mainly by plasmids.
Therefore, we aimed to investigate the occurrence of carbapenemase genes,
analyze the genetic diversity by ERIC-PCR, and examine the most common
plasmid incompatibility groups (Incs) in clinical isolates of K.
pneumoniae from colonization and infection in patients from a
hospital in Brazil. METHODS Twenty-seven isolates of carbapenem-resistant K. pneumoniae
were selected and screened for the presence of carbapenemase genes and Incs
by PCR, followed by amplicon sequencing. RESULTS The blaKPC and blaNDM genes were detected in 24 (88.8 %) and 16 (59.2 %) of the
isolates, respectively. Thirteen isolates (48.1 %) were positive for both
genes. The IncFIB (92.6 %) and IncQ (88.8 %) were the most frequent
plasmids, followed by IncA/C, IncHI1B, and IncL/M, indicating that plasmid
variability existed in these isolates. To our knowledge, this is the first
report of IncHI1B in Brazil. We found eight isolates with clonal
relationship distributed in different sectors of the hospital. CONCLUSIONS The accumulation of resistance determinants, the variability of plasmid
Incs, and the clonal dissemination detected in K.
pneumoniae isolates demonstrate their potential for infection,
colonization, and the dissemination of different resistance genes and
plasmids.
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Affiliation(s)
- Érica Maria de Oliveira
- Universidade Federal de Pernambuco, Centro de Ciências Médicas, Área de Medicina Tropical, Recife, PE, Brasil
| | | | | | | | - Ana Catarina Souza Lopes
- Universidade Federal de Pernambuco, Centro de Ciências Médicas, Área de Medicina Tropical, Recife, PE, Brasil
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Ultrastructural changes caused by the combination of intravenous immunoglobulin with meropenem, amikacin and colistin in multidrug-resistant Acinetobacter baumannii. Microb Pathog 2020; 149:104437. [PMID: 33045338 DOI: 10.1016/j.micpath.2020.104437] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 07/24/2020] [Accepted: 08/03/2020] [Indexed: 01/23/2023]
Abstract
Acinetobacter baumannii is an opportunistic pathogen associated with increased morbidity and mortality in Healthcare-associated infections (HAI). Combination antimicrobial therapy, meropenem, amikacin and colistin, has been used as an alternative in multidrug-resistant (MDR) A. baumannii infections due to reduced treatment options. However, these combinations are not always effective and exhibit high toxicity. Empiric therapy of intravenous immunoglobulin (IVIG) associated with antimicrobials has shown promising results in bacterial infections, considering the immunomodulatory action of IVIG. Thus, the aim of this study was to determine the combined antimicrobial action and to describe the ultrastructural changes caused in ten MDR A. baumannii isolates submitted to IVIG alone and in combination with colistin, meropenem and amikacin. Minimum Inhibitory Concentration (MIC) of antimicrobials and checkerboard were determined. Isolates were submitted to 4 mg/mL of IVIG alone and in combination with different synergistic sub-MIC of antimicrobials tested, and processed for scanning electron microscopy. Nine bacterial isolates showed meropenem-resistant, two isolates had colistin-intermediate, and four isolates were considered intermediate to amikacin. Synergism in five isolates for meropenem/amikacin and meropenem/colistin were observed. Bacterial cells submitted to IVIG and meropenem, amikacin and colistin presented several ultrastructural changes, such as cell elongation and rupture, membrane roughness, incomplete cell division, cell surface "bubbles" and "depression". A. baumannii isolates presented high resistance to meropenem and synergism among evaluated antimicrobials. In addition, it was possible to verify in vitro that IVIG associated with meropenem, amikacin and colistin is a promising alternative for MDR A. baumannii infections. Thus, these data support the continued empirical use and stimulate in vivo analyzes with IVIG to search for new therapeutic options for HAI.
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Yin L, Chen J, Wang K, Geng Y, Lai W, Huang X, Chen D, Guo H, Fang J, Chen Z, Tang L, Huang C, Li N, Ouyang P. Study the antibacterial mechanism of cinnamaldehyde against drug-resistant Aeromonas hydrophila in vitro. Microb Pathog 2020; 145:104208. [PMID: 32325237 DOI: 10.1016/j.micpath.2020.104208] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 04/12/2020] [Accepted: 04/14/2020] [Indexed: 12/22/2022]
Abstract
Aeromonas hydrophila, a highly infectious pathogen, causes several infections in aquatic animals and huge economic losses. Antibiotics are often used to treat A. hydrophila infections. However, overuse and irrational usage of antibiotics has led to severe antibiotic residues and emergence of resistance. There is therefore an urgent need for a new sustainable drug to control bacterial infection. Cinnamaldehyde, a plant-derived ingredient, has been found to have good antibacterial activity against A. hydrophila in vitro, but its mechanism of action remains unknown. In this study, we investigated the mechanism of cinnamaldehyde against A. hydrophila by evaluating the effects of cinnamaldehyde on A. hydrophila cell growth, cell morphology, electrical conductivity, lactate dehydrogenase (LDH), protein metabolism and DNA. The minimal inhibitory concentration and minimum bactericidal concentration of cinnamaldehyde were 256 and 512 μg/mL, respectively. Microscopy results showed disrupted cell wall and membrane, loss of cytoplasm, interior cavitation and unusual binary fission in the cinnamaldehyde-treated group. Electrical conductivity, LDH activity content and DNA extravasation in cinnamaldehyde-treated A. hydrophila increased by 7.14%, 16.75% and 20.29 μg/mL, respectively. Furthermore, nucleic acid fluorescence intensity and density decreased over time in the cinnamaldehyde-treated group. Taken together, these findings suggest that cinnamaldehyde can inhibit the growth of A. hydrophila by disrupting cell membranes and affecting protein metabolism.
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Affiliation(s)
- Lizi Yin
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Jiehao Chen
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Kaiyu Wang
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Yi Geng
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Weiming Lai
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Xiaoli Huang
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Defang Chen
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Hongrui Guo
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Jing Fang
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Zhengli Chen
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Li Tang
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Chao Huang
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
| | - Ningqiu Li
- Key Laboratory of Fishery Drug Development, Ministry of Agriculture, Key Laboratory of Aquatic Animal Immune Technology, Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510380, PR China.
| | - Ping Ouyang
- Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.
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Galbadage T, Liu D, Alemany LB, Pal R, Tour JM, Gunasekera RS, Cirillo JD. Molecular Nanomachines Disrupt Bacterial Cell Wall, Increasing Sensitivity of Extensively Drug-Resistant Klebsiella pneumoniae to Meropenem. ACS NANO 2019; 13:14377-14387. [PMID: 31815423 PMCID: PMC6933815 DOI: 10.1021/acsnano.9b07836] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 12/09/2019] [Indexed: 05/22/2023]
Abstract
Multidrug resistance in pathogenic bacteria is an increasing problem in patient care and public health. Molecular nanomachines (MNMs) have the ability to open cell membranes using nanomechanical action. We hypothesized that MNMs could be used as antibacterial agents by drilling into bacterial cell walls and increasing susceptibility of drug-resistant bacteria to recently ineffective antibiotics. We exposed extensively drug-resistant Klebsiella pneumoniae to light-activated MNMs and found that MNMs increase the susceptibility to Meropenem. MNMs with Meropenem can effectively kill K. pneumoniae that are considered Meropenem-resistant. We examined the mechanisms of MNM action using permeability assays and transmission electron microscopy, finding that MNMs disrupt the cell wall of extensively drug-resistant K. pneumoniae, exposing the bacteria to Meropenem. These observations suggest that MNMs could be used to make conventional antibiotics more efficacious against multi-drug-resistant pathogens.
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Affiliation(s)
- Thushara Galbadage
- Department of Microbial
Pathogenesis and Immunology, Texas A&M
Health Science Center, Bryan, Texas 77807, United States
| | - Dongdong Liu
- Department of Chemistry, Department of Materials
Science and NanoEngineering, Smalley-Curl Institute, NanoCarbon Center, Department of BioSciences, and Shared Equipment
Authority, Rice University, Houston, Texas 77005, United States
| | - Lawrence B. Alemany
- Department of Chemistry, Department of Materials
Science and NanoEngineering, Smalley-Curl Institute, NanoCarbon Center, Department of BioSciences, and Shared Equipment
Authority, Rice University, Houston, Texas 77005, United States
| | - Robert Pal
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - James M. Tour
- Department of Chemistry, Department of Materials
Science and NanoEngineering, Smalley-Curl Institute, NanoCarbon Center, Department of BioSciences, and Shared Equipment
Authority, Rice University, Houston, Texas 77005, United States
- E-mail:
| | - Richard S. Gunasekera
- Department of Chemistry, Department of Materials
Science and NanoEngineering, Smalley-Curl Institute, NanoCarbon Center, Department of BioSciences, and Shared Equipment
Authority, Rice University, Houston, Texas 77005, United States
- Department Biological Science, Biola University, La Mirada, California 90639, United States
- E-mail:
| | - Jeffrey D. Cirillo
- Department of Microbial
Pathogenesis and Immunology, Texas A&M
Health Science Center, Bryan, Texas 77807, United States
- E-mail:
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