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Karas JA, Chen F, Schneider-Futschik EK, Kang Z, Hussein M, Swarbrick J, Hoyer D, Giltrap AM, Payne RJ, Li J, Velkov T. Synthesis and structure-activity relationships of teixobactin. Ann N Y Acad Sci 2019; 1459:86-105. [PMID: 31792983 DOI: 10.1111/nyas.14282] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 11/04/2019] [Accepted: 11/10/2019] [Indexed: 12/15/2022]
Abstract
The discovery of antibiotics has led to the effective treatment of bacterial infections that were otherwise fatal and has had a transformative effect on modern medicine. Teixobactin is an unusual depsipeptide natural product that was recently discovered from a previously unculturable soil bacterium and found to possess potent antibacterial activity against several Gram positive pathogens, including methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococci. One of the key features of teixobactin as an antibiotic lead is that resistance could not be generated in a laboratory setting. This is proposed to be a result of a mechanism of action that involves binding to essential cell wall synthesis building blocks, lipid II and lipid III. Since the initial isolation report in 2015, significant efforts have been made to understand its unique mechanism of action, develop efficient synthetic routes for its production, and thus enable the generation of analogues for structure-activity relationship studies and optimization of its pharmacological properties. Our review provides a comprehensive treatise on the progress in understanding teixobactin chemistry, structure-activity relationships, and mechanisms of antibacterial activity. Teixobactin represents an exciting starting point for the development of new antibiotics that can be used to combat multidrug-resistant bacterial ("superbug") infections.
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Affiliation(s)
- John A Karas
- Department of Pharmacology & Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, the University of Melbourne, Parkville, Victoria, Australia
| | - Fan Chen
- Department of Pharmacology & Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, the University of Melbourne, Parkville, Victoria, Australia
| | - Elena K Schneider-Futschik
- Department of Pharmacology & Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, the University of Melbourne, Parkville, Victoria, Australia.,Lung Health Research Centre, Department of Pharmacology & Therapeutics, the University of Melbourne, Parkville, Victoria, Australia
| | - Zhisen Kang
- Department of Pharmacology & Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, the University of Melbourne, Parkville, Victoria, Australia
| | - Maytham Hussein
- Department of Pharmacology & Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, the University of Melbourne, Parkville, Victoria, Australia
| | - James Swarbrick
- Department of Pharmacology & Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, the University of Melbourne, Parkville, Victoria, Australia
| | - Daniel Hoyer
- Department of Pharmacology & Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, the University of Melbourne, Parkville, Victoria, Australia.,The Florey Institute of Neuroscience and Mental Health, the University of Melbourne, Parkville, Victoria, Australia.,Department of Molecular Medicine, the Scripps Research Institute, La Jolla, California
| | - Andrew M Giltrap
- School of Chemistry, the University of Sydney, Sydney, New South Wales, Australia
| | - Richard J Payne
- School of Chemistry, the University of Sydney, Sydney, New South Wales, Australia
| | - Jian Li
- Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Tony Velkov
- Department of Pharmacology & Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, the University of Melbourne, Parkville, Victoria, Australia
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Yu Z, Tang J, Khare T, Kumar V. The alarming antimicrobial resistance in ESKAPEE pathogens: Can essential oils come to the rescue? Fitoterapia 2019; 140:104433. [PMID: 31760066 DOI: 10.1016/j.fitote.2019.104433] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Revised: 11/15/2019] [Accepted: 11/19/2019] [Indexed: 01/23/2023]
Abstract
Antibiotics, considered as a backbone of modern clinical-medicines, are facing serious threats from emerging antimicrobial-resistance (AMR) in several bacteria from nosocomial and community origins and is posing a serious human-health concern. Recent commitment by the Heads of States at the United Nations General Assembly (UNGA, 2016) for coordinated efforts to curb such infections illustrates the scale of this problem. Amongst the drug-resistant microbes, major threat is posed by the group named as ESKAPEE, an acronym for Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter spp., and Escherichia coli, comprising high to critical drug-resistant, World Health Organization Critical Priority I and II pathogens. The drying pipeline of effective and new antibiotics has worsened the situation with looming threat of heading to a 'post-antibiotic era'. This necessitates novel and effective approaches to combat this life-threatening issue. Medicinal and aromatic plants are hailed as the reservoir of bioactive compounds and can serve as a source of antimicrobial compounds, and some recent leads show that essential oils (EOs) may provide an effective solution for tackling AMR. EOs have shown wide-spectrum antimicrobial potentials via targeting the major determinants of pathogenicity, drug-resistance and its spread including cell membrane, drug efflux pumps, quorum sensing, biofilms and R-plasmids. Latest reports confirm the EOs having strong direct-killing or re-sensitizing potentials to replace or rejuvenate otherwise fading antibiotics arsenal. We discuss herein possibilities of using EOs directly for antimicrobial potentials or in combination with antibiotics to potentiate the later for combating AMR in ESKAPEE pathogens. The current understandings, success stories and challenges for translational success have also been discussed.
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Affiliation(s)
- Zhihui Yu
- Jilin Agricultural Science and Technology College, School of Agronomy, Jilin 132101, China; College of New Energy and Environment, Jilin University, Changchun 130012, China
| | - Jie Tang
- College of New Energy and Environment, Jilin University, Changchun 130012, China.
| | - Tushar Khare
- Department of Biotechnology, Modern College of Arts, Science and Commerce (Savitribai Phule Pune University), Ganeshkhind, Pune 411016, India; Department of Environmental Science, Savitribai Phule Pune University, Pune 411007, India
| | - Vinay Kumar
- Department of Biotechnology, Modern College of Arts, Science and Commerce (Savitribai Phule Pune University), Ganeshkhind, Pune 411016, India; Department of Environmental Science, Savitribai Phule Pune University, Pune 411007, India.
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Molechan C, Amoako DG, Abia ALK, Somboro AM, Bester LA, Essack SY. Molecular epidemiology of antibiotic-resistant Enterococcus spp. from the farm-to-fork continuum in intensive poultry production in KwaZulu-Natal, South Africa. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 692:868-878. [PMID: 31539992 DOI: 10.1016/j.scitotenv.2019.07.324] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 07/19/2019] [Accepted: 07/19/2019] [Indexed: 06/10/2023]
Abstract
The poultry industry is among the main protein suppliers worldwide. Thus, this study determined the antibiotic resistance and virulence profiles of Enterococcus spp. along the farm-to-fork production chain of an intensive poultry system in the uMgungundlovu District, Kwazulu-Natal, South Africa. Overall, 162 samples along the continuum (growth phase, transport and post-slaughter) were evaluated for the presence of Enterococcus spp. using selective media, biochemical tests and polymerase chain reaction (PCR). Resistance profiles were assessed by Kirby-Bauer disk diffusion method following the WHO-AGISAR recommended antibiotics panel for Enterococcus spp. Antibiotic resistance and virulence genes were detected using real-time PCR. Clonal relatedness was evaluated by REP-PCR. Overall, 131 isolates were recovered across the continuum, (34% E. faecalis, 32% E. faecium, 2% E. gallinarum and 32% other Enterococcus spp.). Resistance to tetracycline (79%), erythromycin (70%), nitrofurantoin (18%), ampicillin (15%), streptomycin (15%), chloramphenicol (10%), ciprofloxacin (4%), tigecycline (4%), gentamicin (4%), teicoplanin (3%) was observed among all Enterococcus spp.; no vancomycin resistance (0%) was recorded. Also, 24% of E. faecium were resistant to quinupristin-dalfopristin. Twenty-four multidrug resistance (MDR) antibiograms were observed across all species; E. faecium (43%) showed the highest frequency of MDR. The most frequently observed antibiotic resistomes were tetM (76%) and ermB (66%) while smaller percentages were noted for aph(3')-IIIa (12%) and vanC1 (1%). Virulence genes efaAFs (100%), cpd (96%) and gelE (80%) were more prevalent in E. faecalis. Clonality revealed that isolates along the continuum were highly diverse with major REP-types consisting of isolates from the same sampling point. This study highlights the diversity of MDR Enterococcus in the food chain with isolates harbouring resistance and virulence genes. These could be reservoirs for the potential transfer of pathogenic enterococci carrying these genes from poultry to humans through the food chain continuum, thus, underscoring the need for routine antibiotic resistance surveillance in food animals.
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Affiliation(s)
- Chantal Molechan
- Antimicrobial Research Unit, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Daniel G Amoako
- Antimicrobial Research Unit, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa; Biomedical Resource Unit, School of Laboratory Medicine and Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Akebe Luther King Abia
- Antimicrobial Research Unit, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa.
| | - Anou M Somboro
- Antimicrobial Research Unit, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa; Biomedical Resource Unit, School of Laboratory Medicine and Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Linda A Bester
- Biomedical Resource Unit, School of Laboratory Medicine and Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Sabiha Y Essack
- Antimicrobial Research Unit, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
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Bock LJ. Bacterial biocide resistance: a new scourge of the infectious disease world? Arch Dis Child 2019; 104:1029-1033. [PMID: 30705078 DOI: 10.1136/archdischild-2018-315090] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 12/27/2018] [Accepted: 01/04/2019] [Indexed: 12/17/2022]
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Serwer P, Wright ET, Lee JC. High murine blood persistence of phage T3 and suggested strategy for phage therapy. BMC Res Notes 2019; 12:560. [PMID: 31488211 PMCID: PMC6729040 DOI: 10.1186/s13104-019-4597-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 08/31/2019] [Indexed: 12/11/2022] Open
Abstract
OBJECTIVE Our immediate objective is to determine whether infectivity of lytic podophage T3 has a relatively high persistence in the blood of a mouse, as suggested by previous data. Secondarily, we determine whether the T3 surface has changed during this mouse passage. The surface is characterized by native agarose gel electrophoresis (AGE). Beyond our current data, the long-term objective is optimization of phages chosen for therapy of all bacteremias and associated sepsis. RESULTS We find that the persistence of T3 in mouse blood is higher by over an order of magnitude than the previously reported persistence of (1) lysogenic phages lambda and P22, and (2) lytic phage T7, a T3 relative. We explain these differences via the lysogenic character of lambda and P22, and the physical properties of T7. For the future, we propose testing a new, AGE-based strategy for rapidly screening for high-persistence, lytic, environmental podophages that have phage therapy-promoting physical properties.
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Affiliation(s)
- Philip Serwer
- Department of Biochemistry and Structural Biology, The University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900 USA
| | - Elena T. Wright
- Department of Biochemistry and Structural Biology, The University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900 USA
| | - John C. Lee
- Department of Biochemistry and Structural Biology, The University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900 USA
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Xu D, Wang J, Guo C, Peng XX, Li H. Elevated biosynthesis of palmitic acid is required for zebrafish against Edwardsiella tarda infection. FISH & SHELLFISH IMMUNOLOGY 2019; 92:508-518. [PMID: 31247319 DOI: 10.1016/j.fsi.2019.06.041] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 06/22/2019] [Accepted: 06/23/2019] [Indexed: 06/09/2023]
Abstract
Mechanisms by which vaccines enhance immunity to combat bacterial pathogens are not fully understood. Recently, we have found that live Edwardsiella tarda vaccine enhances ability against the bacterial challenge by metabolic modulation in zebrafish. Here we first explored the metabolic modulation promoted by inactivated E. tarda to eliminate the pathogen. Inactivated E. tarda vaccine modulated a similar metabolome to combat with the pathogen in zebrafish as live E. tarda vaccine did. Specifically, both vaccines promoted biosynthesis of unsaturated fatty acids and the TCA cycle. However, due to relatively higher activated TCA cycle in inactivated vaccine than live vaccine, live vaccine promoted higher abundance of palmitate than inactivated vaccine. Consistently, the protection against E. tarda challenge was palmitate dose-dependent. Live vaccine activated higher expression of IL-1β, IL-8,Cox-2 genes and lower expression of IL-15, IL-21 genes than inactivated vaccine, which is similar to the results stimulated by high and low doses of palmitate, respectively. These findings indicate live and inactivated E. tarda vaccines stimulate differential abundances of palmitate that contribute to differential innate immunities against bacterial infection. Thus, metabolic environment contributes to immune response.
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Affiliation(s)
- Di Xu
- Center for Proteomics and Metabolomics, State Key Laboratory of Bio-Control, Sun Yat-sen University, University City, Guangzhou, 510006, People's Republic of China
| | - Jie Wang
- Center for Proteomics and Metabolomics, State Key Laboratory of Bio-Control, Sun Yat-sen University, University City, Guangzhou, 510006, People's Republic of China
| | - Chang Guo
- Center for Proteomics and Metabolomics, State Key Laboratory of Bio-Control, Sun Yat-sen University, University City, Guangzhou, 510006, People's Republic of China
| | - Xuan-Xian Peng
- Center for Proteomics and Metabolomics, State Key Laboratory of Bio-Control, Sun Yat-sen University, University City, Guangzhou, 510006, People's Republic of China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, People's Republic of China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519000, People's Republic of China
| | - Hui Li
- Center for Proteomics and Metabolomics, State Key Laboratory of Bio-Control, Sun Yat-sen University, University City, Guangzhou, 510006, People's Republic of China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, People's Republic of China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519000, People's Republic of China.
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Velkov T, Swarbrick JD, Hussein MH, Schneider-Futschik EK, Hoyer D, Li J, Karas JA. The impact of backbone N-methylation on the structure-activity relationship of Leu 10 -teixobactin. J Pept Sci 2019; 25:e3206. [PMID: 31389086 DOI: 10.1002/psc.3206] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 06/29/2019] [Accepted: 07/03/2019] [Indexed: 11/07/2022]
Abstract
Antimicrobial resistance is a serious threat to global human health; therefore, new anti-infective therapeutics are required. The cyclic depsi-peptide teixobactin exhibits potent antimicrobial activity against several Gram-positive pathogens. To study the natural product's mechanism of action and improve its pharmacological properties, efficient chemical methods for preparing teixobactin analogues are required to expedite structure-activity relationship studies. Described herein is a synthetic route that enables rapid access to analogues. Furthermore, our new N-methylated analogues highlight that hydrogen bonding along the N-terminal tail is likely to be important for antimicrobial activity.
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Affiliation(s)
- Tony Velkov
- Department of Pharmacology and Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, Victoria, Australia
| | - James D Swarbrick
- Department of Pharmacology and Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Maytham H Hussein
- Department of Pharmacology and Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Elena K Schneider-Futschik
- Department of Pharmacology and Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, Victoria, Australia
- Lung Health Research Centre, Department of Pharmacology and Therapeutics, The University of Melbourne, Parkville, Victoria, Australia
| | - Daniel Hoyer
- Department of Pharmacology and Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, Victoria, Australia
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California
| | - Jian Li
- Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - John A Karas
- Department of Pharmacology and Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, Victoria, Australia
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Prevention of urinary catheter-associated infections by coating antimicrobial peptides from crowberry endophytes. Sci Rep 2019; 9:10753. [PMID: 31341199 PMCID: PMC6656713 DOI: 10.1038/s41598-019-47108-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 06/24/2019] [Indexed: 11/08/2022] Open
Abstract
Urinary catheters are extensively used in hospitals, being responsible for about 75% of hospital-acquired infections. In this work, a de novo designed antimicrobial peptide (AMP) Chain201D was studied in the context of urinary catheter-associated infections. Chain201D showed excellent antimicrobial activity against relevant ATCC strains and clinical isolates of bacteria and yeast and demonstrated high stability in a wide range of temperatures, pH and salt concentrations. Moreover, the bactericidal activity of Chain201D immobilized on a model surface was studied against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), some of the most prevalent strains found in urinary catheter-associated infections. Chain201D was successfully tethered to ((1-mercapto-11-undecyl)-(tetra(ethylene glycol) (EG4)) terminated self-assembled monolayers (SAMs), (EG4-SAMs), activated by 1,1'-Carbonyldiimidazole (CDI) at different concentrations. Chain201D surfaces can bind and kill by contact a high percentage of adherent bacteria. These achievements are obtained without any peptide modification (for chemoselective conjugation) and without the use of a spacer. Moreover, increased amounts of immobilized AMP lead to higher numbers of adhered/dead bacteria, revealing a concentration-dependent behaviour and demonstrating that Chain201D has excellent potential for developing antimicrobial urinary catheters.
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Matougui N, Groo AC, Umerska A, Cassisa V, Saulnier P. A comparison of different strategies for antimicrobial peptides incorporation onto/into lipid nanocapsules. Nanomedicine (Lond) 2019; 14:1647-1662. [DOI: 10.2217/nnm-2018-0337] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Aim: Over the last decade, antimicrobial peptides (AMPs) have emerged as a promising alternative for the treatment of various infections. The aim of this work is to explore the potential of lipid nanocapsules for the delivery of AMPs. Three approaches were compared in terms of encapsulation efficiency, peptide activity and protection against proteases: peptide encapsulation, surface adsorption or covalent attachment of three selected AMPs. Results: A potentiation of the antimicrobial activity and a partial protection of the peptides after adsorption were demonstrated compared with native peptides. Conversely, encapsulation allowed better peptide stability, correlated with higher encapsulation efficiencies and a preservation of the activity. Finally, the covalent attachment strategy turned out to be less conclusive due to peptide inactivation. Conclusion: In brief, a lipid nanocapsule-based platform appears suitable to deliver AMPs.
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Affiliation(s)
- Nada Matougui
- Micro & Nanomédecines Translationelles-MINT, UNIV Angers, INSERM U1066, CNRS UMR 6021, UBL Universite Bretagne Loire, Angers F-49933, France
| | - Anne-Claire Groo
- Normandie Univ, UNICAEN, CERMN – EA 4258, FR CNRS 3038 INC3M, SF 4206 ICORE, Caen, France
| | - Anita Umerska
- Micro & Nanomédecines Translationelles-MINT, UNIV Angers, INSERM U1066, CNRS UMR 6021, UBL Universite Bretagne Loire, Angers F-49933, France
- Université de Lorraine, CITHEFOR, Nancy, France
| | - Viviane Cassisa
- Equipe 7b, ATIP Avenir, ATOMyca, U892, CRCNA, CHU Angers, France
| | - Patrick Saulnier
- Micro & Nanomédecines Translationelles-MINT, UNIV Angers, INSERM U1066, CNRS UMR 6021, UBL Universite Bretagne Loire, Angers F-49933, France
- University Hospital Department of Biostatistics and Methodology, Angers University Hospital, Angers, France
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Imani Rad H, Peeri H, Amani M, Mohammadnia A, Ogunniyi AD, Khazandi M, Venter H, Arzanlou M. Allicin prevents the formation of Proteus-induced urinary crystals and the blockage of catheter in a bladder model in vitro. Microb Pathog 2019; 132:293-301. [PMID: 31082531 DOI: 10.1016/j.micpath.2019.05.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 05/08/2019] [Accepted: 05/09/2019] [Indexed: 10/26/2022]
Abstract
Stone formation and catheter blockage are major complications of Proteus UTIs. In this study, we investigated the ability of allicin to inhibit P. mirabilis-induced struvite crystallization and catheter blockage using a synthetic bladder model. Struvite crystallization inhibition study was carried out using P. mirabilis lysate as urease enzyme source in synthetic urine (SU). Struvite productions were monitored by phase contrast light microscopy and measurements of pH, Mg2+ and Ca2+ precipitation and turbidity. A catheter blockage study was performed in a synthetic bladder model mimicking natural UTI in the presence of allicin at sub-MIC concentrations (MIC = 64 μg/ml). The results of crystallization study showed that allicin inhibited pH rise and consequently turbidity and precipitation of ions in a dose-dependent manner. The results of catheter blockage study showed that allicin at sub-MIC concentrations (2, 4, 8 μg/ml) significantly increased the time for catheter blockage to occur to 61, 74 and 92 h respectively compared to allicin-free control (48 h). In a similar way, the results showed that allicin delayed the increase of SU pH level in bladder model in a dose-dependent manner compared to allicin-free control. The results also showed that following the increase of allicin concentration, Mg2+ and Ca2+ deposition in catheters were much lower compared to allicin-free control, further confirmed by direct observation of the catheters' eyehole and cross sections. We conclude that allicin prevents the formation of Proteus-induced urinary crystals and the blockage of catheters by delaying pH increase and lowering Mg2+ and Ca2+ deposition in a dose-dependent manner.
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Affiliation(s)
- Hamed Imani Rad
- Department of Microbiology, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran
| | - Hadi Peeri
- Department of Microbiology, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran
| | - Mojtaba Amani
- Department of Clinical Chemistry, School of Pharmacy, Ardabil University of Medical Sciences, Ardabil, Iran; Department of Biochemistry, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran
| | - Alireza Mohammadnia
- Department of Information Technologies, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran
| | - Abiodun David Ogunniyi
- Australian Centre for Antimicrobial Resistance Ecology, School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, South Australia, Australia
| | - Manouchehr Khazandi
- Australian Centre for Antimicrobial Resistance Ecology, School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, South Australia, Australia
| | - Henrietta Venter
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, 5000, Australia
| | - Mohsen Arzanlou
- Department of Microbiology, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran.
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Venter H. Reversing resistance to counter antimicrobial resistance in the World Health Organisation's critical priority of most dangerous pathogens. Biosci Rep 2019; 39:BSR20180474. [PMID: 30910848 PMCID: PMC6465202 DOI: 10.1042/bsr20180474] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 03/18/2019] [Accepted: 03/22/2019] [Indexed: 02/07/2023] Open
Abstract
The speed at which bacteria develop antimicrobial resistance far outpace drug discovery and development efforts resulting in untreatable infections. The World Health Organisation recently released a list of pathogens in urgent need for the development of new antimicrobials. The organisms that are listed as the most critical priority are all Gram-negative bacteria resistant to the carbapenem class of antibiotics. Carbapenem resistance in these organisms is typified by intrinsic resistance due to the expression of antibiotic efflux pumps and the permeability barrier presented by the outer membrane, as well as by acquired resistance due to the acquisition of enzymes able to degrade β-lactam antibiotics. In this perspective article we argue the case for reversing resistance by targeting these resistance mechanisms - to increase our arsenal of available antibiotics and drastically reduce antibiotic discovery times - as the most effective way to combat antimicrobial resistance in these high priority pathogens.
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Affiliation(s)
- Henrietta Venter
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia
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62
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Cieplik F, Jakubovics NS, Buchalla W, Maisch T, Hellwig E, Al-Ahmad A. Resistance Toward Chlorhexidine in Oral Bacteria - Is There Cause for Concern? Front Microbiol 2019; 10:587. [PMID: 30967854 PMCID: PMC6439480 DOI: 10.3389/fmicb.2019.00587] [Citation(s) in RCA: 195] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 03/07/2019] [Indexed: 12/20/2022] Open
Abstract
The threat of antibiotic resistance has attracted strong interest during the last two decades, thus stimulating stewardship programs and research on alternative antimicrobial therapies. Conversely, much less attention has been given to the directly related problem of resistance toward antiseptics and biocides. While bacterial resistances toward triclosan or quaternary ammonium compounds have been considered in this context, the bis-biguanide chlorhexidine (CHX) has been put into focus only very recently when its use was associated with emergence of stable resistance to the last-resort antibiotic colistin. The antimicrobial effect of CHX is based on damaging the bacterial cytoplasmic membrane and subsequent leakage of cytoplasmic material. Consequently, mechanisms conferring resistance toward CHX include multidrug efflux pumps and cell membrane changes. For instance, in staphylococci it has been shown that plasmid-borne qac ("quaternary ammonium compound") genes encode Qac efflux proteins that recognize cationic antiseptics as substrates. In Pseudomonas stutzeri, changes in the outer membrane protein and lipopolysaccharide profiles have been implicated in CHX resistance. However, little is known about the risk of resistance toward CHX in oral bacteria and potential mechanisms conferring this resistance or even cross-resistances toward antibiotics. Interestingly, there is also little awareness about the risk of CHX resistance in the dental community even though CHX has been widely used in dental practice as the gold-standard antiseptic for more than 40 years and is also included in a wide range of oral care consumer products. This review provides an overview of general resistance mechanisms toward CHX and the evidence for CHX resistance in oral bacteria. Furthermore, this work aims to raise awareness among the dental community about the risk of resistance toward CHX and accompanying cross-resistance to antibiotics. We propose new research directions related to the effects of CHX on bacteria in oral biofilms.
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Affiliation(s)
- Fabian Cieplik
- Department of Conservative Dentistry and Periodontology, University Medical Center Regensburg, Regensburg, Germany
| | - Nicholas S Jakubovics
- Centre for Oral Health Research, School of Dental Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Wolfgang Buchalla
- Department of Conservative Dentistry and Periodontology, University Medical Center Regensburg, Regensburg, Germany
| | - Tim Maisch
- Department of Dermatology, University Medical Center Regensburg, Regensburg, Germany
| | - Elmar Hellwig
- Department of Operative Dentistry and Periodontology, Center for Dental Medicine, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
| | - Ali Al-Ahmad
- Department of Operative Dentistry and Periodontology, Center for Dental Medicine, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
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Antonova NP, Vasina DV, Lendel AM, Usachev EV, Makarov VV, Gintsburg AL, Tkachuk AP, Gushchin VA. Broad Bactericidal Activity of the Myoviridae Bacteriophage Lysins LysAm24, LysECD7, and LysSi3 against Gram-Negative ESKAPE Pathogens. Viruses 2019; 11:v11030284. [PMID: 30901901 PMCID: PMC6466606 DOI: 10.3390/v11030284] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 03/18/2019] [Accepted: 03/19/2019] [Indexed: 11/30/2022] Open
Abstract
The extremely rapid spread of multiple-antibiotic resistance among Gram-negative pathogens threatens to move humankind into the so-called “post-antibiotic era” in which the most efficient and safe antibiotics will not work. Bacteriophage lysins represent promising alternatives to antibiotics, as they are capable of digesting bacterial cell wall peptidoglycans to promote their osmotic lysis. However, relatively little is known regarding the spectrum of lysin bactericidal activity against Gram-negative bacteria. In this study, we present the results of in vitro activity assays of three putative and newly cloned Myoviridae bacteriophage endolysins (LysAm24, LysECD7, and LysSi3). The chosen proteins represent lysins with diverse domain organization (single-domain vs. two-domain) and different predicted mechanisms of action (lysozyme vs. peptidase). The enzymes were purified, and their properties were characterized. The enzymes were tested against a panel of Gram-negative clinical bacterial isolates comprising all Gram-negative representatives of the ESKAPE group. Despite exhibiting different structural organizations, all of the assayed lysins were shown to be capable of lysing Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella pneumoniae, Escherichia coli, and Salmonella typhi strains. Less than 50 μg/mL was enough to eradicate growing cells over more than five orders of magnitude. Thus, LysAm24, LysECD7, and LysSi3 represent promising therapeutic agents for drug development.
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Affiliation(s)
- Nataliia P Antonova
- N.F. Gamaleya Federal Research Centre for Epidemiology and Microbiology, Ministry of Health of the Russian Federation, 123098 Moscow, Russia.
- Lomonosov Moscow State University, 119991 Moscow, Russia.
| | - Daria V Vasina
- N.F. Gamaleya Federal Research Centre for Epidemiology and Microbiology, Ministry of Health of the Russian Federation, 123098 Moscow, Russia.
| | | | - Evgeny V Usachev
- N.F. Gamaleya Federal Research Centre for Epidemiology and Microbiology, Ministry of Health of the Russian Federation, 123098 Moscow, Russia.
| | - Valentine V Makarov
- Center for Strategic Planning of the Ministry of Health of the Russian Federation, 119435 Moscow, Russia.
| | - Alexander L Gintsburg
- N.F. Gamaleya Federal Research Centre for Epidemiology and Microbiology, Ministry of Health of the Russian Federation, 123098 Moscow, Russia.
| | - Artem P Tkachuk
- N.F. Gamaleya Federal Research Centre for Epidemiology and Microbiology, Ministry of Health of the Russian Federation, 123098 Moscow, Russia.
| | - Vladimir A Gushchin
- N.F. Gamaleya Federal Research Centre for Epidemiology and Microbiology, Ministry of Health of the Russian Federation, 123098 Moscow, Russia.
- Lomonosov Moscow State University, 119991 Moscow, Russia.
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64
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Skoufos I, Tzora A, Giannenas I, Bonos E, Tsinas A, ΜcCartney Ε, Lester H, Christaki E, Florou-Paneri P, Mahdavi J, Soultanas P. Evaluation of in-field efficacy of dietary ferric tyrosine on performance, intestinal health and meat quality of broiler chickens exposed to natural Campylobacter jejuni challenge. Livest Sci 2019. [DOI: 10.1016/j.livsci.2019.01.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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65
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Groo AC, Matougui N, Umerska A, Saulnier P. Reverse micelle-lipid nanocapsules: a novel strategy for drug delivery of the plectasin derivate AP138 antimicrobial peptide. Int J Nanomedicine 2018; 13:7565-7574. [PMID: 30532539 PMCID: PMC6241861 DOI: 10.2147/ijn.s180040] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Introduction Resistance to traditional antibiotics is an increasingly serious problem. Antimicrobial peptides (AMPs) have emerged as a new therapeutic class with great potential against infectious diseases, as they are less prone to induce resistance. Nanotechnology-based delivery strategies can improve the efficiency and stability of AMPs, particularly against proteolytic degradation. Lipid nanocapsules (LNCs) are a new generation of biomimetic nanocarriers and were used in this study to deliver peptides. Methods AMP-loaded reverse micelles (RM) were developed and incorpo rated into LNCs by the phase inversion process and the antimicrobial activity of the AMPs-loaded LNC was evaluated by the minimum inhibitory concentration method. We studied the activity of AMP solutions and AMP-loaded LNCs against Gram-positive and Gram-negative bacterial strains and then evaluated the encapsulation of a new cationic AMP called AP138. Finally, we analyzed the effect of enzymatic attack on AP138 and AP138-RM-LNCs after incubation with trypsin. Results AP138 was efficiently encapsulated in the LNCs (encapsulation efficiency = 97.8% at a drug loading of 0.151%), resulting in protection against degradation by proteases and the preservation of antimicrobial activity against Staphylococcus aureus, including methicillin-resistant Staphylococcus aureus. Conclusion This study shows that RM-LNCs are an excellent candidate system to deliver AMPs.
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Affiliation(s)
- Anne-Claire Groo
- Normandie Univ, UNICAEN, CERMN - EA 4258, FR CNRS 3038 INC3M, SF 4206 ICORE, Caen, France,
| | - Nada Matougui
- Micro & Nanomédecines Translationelles-MINT, UNIV Angers, INSERM U1066, CNRS UMR 6021, UBL Universite Bretagne Loire, Angers, France
| | - Anita Umerska
- Micro & Nanomédecines Translationelles-MINT, UNIV Angers, INSERM U1066, CNRS UMR 6021, UBL Universite Bretagne Loire, Angers, France.,Université de Lorraine, CITHEFOR, Nancy, France
| | - Patrick Saulnier
- Micro & Nanomédecines Translationelles-MINT, UNIV Angers, INSERM U1066, CNRS UMR 6021, UBL Universite Bretagne Loire, Angers, France.,Angers University Hospital, Angers, France
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66
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Wen PC, Vanegas JM, Rempe SB, Tajkhorshid E. Probing key elements of teixobactin-lipid II interactions in membranes. Chem Sci 2018; 9:6997-7008. [PMID: 30210775 PMCID: PMC6124899 DOI: 10.1039/c8sc02616e] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Accepted: 07/19/2018] [Indexed: 12/18/2022] Open
Abstract
Two binding poses of the teixobactin–lipid II complex were captured with MD simulations at the membrane surface.
Teixobactin (Txb) is a recently discovered antibiotic against Gram-positive bacteria that induces no detectable resistance. The bactericidal mechanism is believed to be the inhibition of cell wall biosynthesis by Txb binding to lipid II and lipid III. Txb binding specificity likely arises from targeting of the shared lipid component, the pyrophosphate moiety. Despite synthesis and functional assessment of numerous chemical analogs of Txb, and consequent identification of the Txb pharmacophore, the detailed structural information of Txb–substrate binding is still lacking. Here, we use molecular modeling and microsecond-scale molecular dynamics simulations to capture the formation of Txb–lipid II complexes at a membrane surface. Two dominant binding conformations were observed, both showing characteristic lipid II phosphate binding by the Txb backbone amides near the C-terminal cyclodepsipeptide (d-Thr8–Ile11) ring. Additionally, binding by Txb also involved the side chain hydroxyl group of Ser7, as well as a secondary phosphate binding provided by the side chain of l-allo-enduracididine. Interestingly, those conformations differ by swapping two groups of hydrogen bond donors that coordinate the two phosphate moieties of lipid II, resulting in opposite orientations of lipid II binding. In addition, residues d-allo-Ile5 and Ile6 serve as the membrane anchors in both Txb conformations, regardless of the detailed phosphate binding interactions near the cyclodepsipeptide ring. The role of hydrophobic residues in Txb activity is primarily for its membrane insertion, and subsidiarily to provide non-polar interactions with the lipid II tail. Based on the Txb–lipid II interactions captured in their complexes, as well as their partitioning depths into the membrane, we propose that the bactericidal mechanism of Txb is to arrest cell wall synthesis by selectively inhibiting the transglycosylation of peptidoglycan, while possibly leaving the transpeptidation step unaffected. The observed “pyrophosphate caging” mechanism of lipid II inhibition appears to be similar to some lantibiotics, but different from that of vancomycin or bacitracin.
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Affiliation(s)
- Po-Chao Wen
- Department of Biochemistry , Center for Biophysics and Quantitative Biology , Beckman Institute for Advanced Science and Technology , University of Illinois at Urbana-Champaign , Urbana , Illinois 61801 , USA . ;
| | - Juan M Vanegas
- Department of Nanobiology , Center for Biological and Engineering Sciences , Sandia National Laboratories , Albuquerque , NM 87185 , USA .
| | - Susan B Rempe
- Department of Nanobiology , Center for Biological and Engineering Sciences , Sandia National Laboratories , Albuquerque , NM 87185 , USA .
| | - Emad Tajkhorshid
- Department of Biochemistry , Center for Biophysics and Quantitative Biology , Beckman Institute for Advanced Science and Technology , University of Illinois at Urbana-Champaign , Urbana , Illinois 61801 , USA . ;
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Jutkina J, Marathe NP, Flach CF, Larsson DGJ. Antibiotics and common antibacterial biocides stimulate horizontal transfer of resistance at low concentrations. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 616-617:172-178. [PMID: 29112840 DOI: 10.1016/j.scitotenv.2017.10.312] [Citation(s) in RCA: 176] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 10/28/2017] [Accepted: 10/30/2017] [Indexed: 05/08/2023]
Abstract
There is a rising concern that antibiotics, and possibly other antimicrobial agents, can promote horizontal transfer of antibiotic resistance genes. For most types of antimicrobials their ability to induce conjugation below minimal inhibitory concentrations (MICs) is still unknown. Our aim was therefore to explore the potential of commonly used antibiotics and antibacterial biocides to induce horizontal transfer of antibiotic resistance. Effects of a wide range of sub-MIC concentrations of the antibiotics cefotaxime, ciprofloxacin, gentamicin, erythromycin, sulfamethoxazole, trimethoprim and the antibacterial biocides chlorhexidine digluconate, hexadecyltrimethylammoniumchloride and triclosan were investigated using a previously optimized culture-based assay with a complex bacterial community as a donor of mobile resistance elements and a traceable Escherichia coli strain as a recipient. Chlorhexidine (24.4μg/L), triclosan (0.1mg/L), gentamicin (0.1mg/L) and sulfamethoxazole (1mg/L) significantly increased the frequencies of transfer of antibiotic resistance whereas similar effects were not observed for any other tested antimicrobial compounds. This corresponds to 200 times below the MIC of the recipient for chlorhexidine, 1/20 of the MIC for triclosan, 1/16 of the MIC for sulfamethoxazole and right below the MIC for gentamicin. To our best knowledge, this is the first study showing that triclosan and chlorhexidine could stimulate the horizontal transfer of antibiotic resistance. Together with recent research showing that tetracycline is a potent inducer of conjugation, our results indicate that several antimicrobials including both common antibiotics and antibacterial biocides at low concentrations could contribute to antibiotic resistance development by facilitating the spread of antibiotic resistance between bacteria.
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Affiliation(s)
- J Jutkina
- Centre for Antibiotic Resistance Research (CARe) at University of Gothenburg, Sweden; Department of Infectious Diseases, Institute of Biomedicine, The Sahlgrenska Academy at University of Gothenburg, Sweden
| | - N P Marathe
- Centre for Antibiotic Resistance Research (CARe) at University of Gothenburg, Sweden; Department of Infectious Diseases, Institute of Biomedicine, The Sahlgrenska Academy at University of Gothenburg, Sweden
| | - C-F Flach
- Centre for Antibiotic Resistance Research (CARe) at University of Gothenburg, Sweden; Department of Infectious Diseases, Institute of Biomedicine, The Sahlgrenska Academy at University of Gothenburg, Sweden
| | - D G J Larsson
- Centre for Antibiotic Resistance Research (CARe) at University of Gothenburg, Sweden; Department of Infectious Diseases, Institute of Biomedicine, The Sahlgrenska Academy at University of Gothenburg, Sweden.
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68
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Nanomaterials for the Abatement of Pharmaceuticals and Personal Care Products from Wastewater. APPLIED SCIENCES-BASEL 2018. [DOI: 10.3390/app8020170] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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69
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Ma Q, Fu Y, Sun H, Huang Y, Li L, Yu Q, Dinnyes A, Sun Q. Antimicrobial resistance of Lactobacillus spp. from fermented foods and human gut. Lebensm Wiss Technol 2017. [DOI: 10.1016/j.lwt.2017.07.059] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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70
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Mowla R, Wang Y, Ma S, Venter H. Kinetic analysis of the inhibition of the drug efflux protein AcrB using surface plasmon resonance. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1860:878-886. [PMID: 28890187 DOI: 10.1016/j.bbamem.2017.08.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 08/19/2017] [Accepted: 08/31/2017] [Indexed: 11/24/2022]
Abstract
Multidrug efflux protein complexes such as AcrAB-TolC from Escherichia coli are paramount in multidrug resistance in Gram-negative bacteria and are also implicated in other processes such as virulence and biofilm formation. Hence efflux pump inhibition, as a means to reverse antimicrobial resistance in clinically relevant pathogens, has gained increased momentum over the past two decades. Significant advances in the structural and functional analysis of AcrB have informed the selection of efflux pump inhibitors (EPIs). However, an accurate method to determine the kinetics of efflux pump inhibition was lacking. In this study we standardised and optimised surface plasmon resonance (SPR) to probe the binding kinetics of substrates and inhibitors to AcrB. The SPR method was also combined with a fluorescence drug binding method by which affinity of two fluorescent AcrB substrates were determined using the same conditions and controls as for SPR. Comparison of the results from the fluorescent assay to those of the SPR assay showed excellent correlation and provided validation for the methods and conditions used for SPR. The kinetic parameters of substrate (doxorubicin, novobiocin and minocycline) binding to AcrB were subsequently determined. Lastly, the kinetics of inhibition of AcrB were probed for two established inhibitors (phenylalanine arginyl β-naphthylamide and 1-1-naphthylmethyl-piperazine) and three novel EPIs: 4-isobutoxy-2-naphthamide (A2), 4-isopentyloxy-2-naphthamide (A3) and 4-benzyloxy-2-naphthamide (A9) have also been probed. The kinetic data obtained could be correlated with inhibitor efficacy and mechanism of action. This study is the first step in the quantitative analysis of the kinetics of inhibition of the clinically important RND-class of multidrug efflux pumps and will allow the design of improved and more potent inhibitors of drug efflux pumps. This article is part of a Special Issue entitled: Beyond the Structure-Function Horizon of Membrane Proteins edited by Ute Hellmich, Rupak Doshi and Benjamin McIlwain.
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Affiliation(s)
- Rumana Mowla
- School of Pharmacy and Medical Sciences, Sansom Institute for Health Research, University of South Australia, SA 5000, Australia
| | - Yinhu Wang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology, School of Pharmaceutical Sciences, Shandong University, Jinan 250012, China
| | - Shutao Ma
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology, School of Pharmaceutical Sciences, Shandong University, Jinan 250012, China
| | - Henrietta Venter
- School of Pharmacy and Medical Sciences, Sansom Institute for Health Research, University of South Australia, SA 5000, Australia.
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Skariyachan S, Garka S, Puttaswamy S, Shanbhogue S, Devaraju R, Narayanappa R. Environmental monitoring and assessment of antibacterial metabolite producing actinobacteria screened from marine sediments in south coastal regions of Karnataka, India. ENVIRONMENTAL MONITORING AND ASSESSMENT 2017; 189:283. [PMID: 28534309 DOI: 10.1007/s10661-017-5999-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 05/09/2017] [Indexed: 06/07/2023]
Abstract
Assessment of the therapeutic potential of secondary metabolite producing microorganisms from the marine coastal areas imparts scope and application in the field of environmental monitoring. The present study aims to screen metabolites with antibacterial potential from actionbacteria associated with marine sediments collected from south coastal regions of Karnataka, India. The actinobacteria were isolated and characterized from marine sediments by standard protocol. The metabolites were extracted, and antibacterial potential was analyzed against eight hospital associated bacteria. The selected metabolites were partially characterized by proximate analysis, SDS-PAGE, and FTIR-spectroscopy. The antibiogram of the test clinical isolates revealed that they were emerged as multidrug-resistant strains (P ≤ 0.05). Among six actinobacteria (IS1-1S6) screened, 100 μl-1 metabolite from IS1 showed significant antibacterial activities against all the clinical isolates except Pseudomonas aeruginosa. IS2 demonstrated antimicrobial potential towards Proteus mirabilis, Streptococcus pyogenes, and Escherichia coli. The metabolite from IS3 showed activity against Strep. pyogenes and E. coli. The metabolites from IS4, IS5, and IS6 exhibited antimicrobial activities against Ps. aeruginosa (P ≤ 0.05). The two metabolites that depicted highest antibacterial activities against the test strains were suggested to be antimicrobial peptides with low molecular weight. These isolates were characterized and designated as Streptomyces sp. strain mangaluru01 and Streptomyces sp. mangaloreK01 by 16S ribosomal DNA (rDNA) sequencing. This study suggests that south coastal regions of Karnataka, India, are one of the richest sources of antibacterial metabolites producing actinobacteria and monitoring of these regions for therapeutic intervention plays profound role in healthcare management.
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Affiliation(s)
- Sinosh Skariyachan
- R & D Centre, Department of Biotechnology, Dayananda Sagar College of Engineering, Bangalore, Karnataka, 560078, India.
| | - Shruthi Garka
- R & D Centre, Department of Biotechnology, Dayananda Sagar College of Engineering, Bangalore, Karnataka, 560078, India
| | - Sushmitha Puttaswamy
- R & D Centre, Department of Biotechnology, Dayananda Sagar College of Engineering, Bangalore, Karnataka, 560078, India
| | - Shobitha Shanbhogue
- R & D Centre, Department of Biotechnology, Dayananda Sagar College of Engineering, Bangalore, Karnataka, 560078, India
| | - Raksha Devaraju
- R & D Centre, Department of Biotechnology, Dayananda Sagar College of Engineering, Bangalore, Karnataka, 560078, India
| | - Rajeswari Narayanappa
- R & D Centre, Department of Biotechnology, Dayananda Sagar College of Engineering, Bangalore, Karnataka, 560078, India
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Rasigade JP. Catching the evader: Can monoclonal antibodies interfere with Staphylococcus aureus immune escape? Virulence 2017; 9:1-4. [PMID: 28441093 PMCID: PMC5955477 DOI: 10.1080/21505594.2017.1320012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
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