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Hilpert K, Munshi T, López-Pérez PM, Sequeira-Garcia J, Bull TJ. Redefining Peptide 14D: Substitutional Analysis for Accelerated TB Diagnosis and Enhanced Activity against Mycobacterium tuberculosis. Microorganisms 2024; 12:177. [PMID: 38258003 PMCID: PMC10819809 DOI: 10.3390/microorganisms12010177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 01/08/2024] [Accepted: 01/12/2024] [Indexed: 01/24/2024] Open
Abstract
Tuberculosis (TB) caused by Mycobacterium tuberculosis remains a predominant cause of mortality, especially in low- and middle-income nations. Recently, antimicrobial peptides have been discovered that at low concentrations could stimulate the growth of M. tuberculosis (hormetic response). In this study, such a peptide was used to investigate the effects on the time to positivity (TTP). A systematic substitution analysis of peptide 14D was synthesized using Spot synthesis technology, resulting in 171 novel peptides. Our findings revealed a spectrum of interactions, with some peptides accelerating M. tuberculosis growth, potentially aiding in faster diagnostics, while others exhibited inhibitory effects. Notably, peptide NH2-wkivfiwrr-CONH2 significantly reduced the TTP by 25 h compared to the wild-type peptide 14D, highlighting its potential in improving TB diagnostics by culture. Several peptides demonstrated potent antimycobacterial activity, with a minimum inhibitory concentration (MIC) of 20 µg/mL against H37Rv and a multidrug-resistant M. tuberculosis strain. Additionally, for two peptides, a strongly diminished formation of cord-like structures was observed, which is indicative of reduced virulence and transmission potential. This study underscores the multifaceted roles of antimicrobial peptides in TB management, from enhancing diagnostic efficiency to offering therapeutic avenues against M. tuberculosis.
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Affiliation(s)
- Kai Hilpert
- Institute of Infection and Immunity, St George’s, University of London, Cranmer Terrace, London SW17 0RE, UK
| | - Tulika Munshi
- Institute of Infection and Immunity, St George’s, University of London, Cranmer Terrace, London SW17 0RE, UK
| | | | | | - Tim J. Bull
- Institute of Infection and Immunity, St George’s, University of London, Cranmer Terrace, London SW17 0RE, UK
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Bull TJ, Munshi T, Lopez-Perez PM, Tran AC, Cosgrove C, Bartolf A, Menichini M, Rindi L, Parigger L, Malanovic N, Lohner K, Wang CJH, Fatima A, Martin LL, Esin S, Batoni G, Hilpert K. Specific Cationic Antimicrobial Peptides Enhance the Recovery of Low-Load Quiescent Mycobacterium tuberculosis in Routine Diagnostics. Int J Mol Sci 2023; 24:17555. [PMID: 38139385 PMCID: PMC10743970 DOI: 10.3390/ijms242417555] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 12/07/2023] [Accepted: 12/11/2023] [Indexed: 12/24/2023] Open
Abstract
The culture confirmation of Mycobacterium tuberculosis (MTB) remains the gold standard for the diagnosis of Tuberculosis (TB) with culture conversion representing proof of cure. However, over 40% of TB samples fail to isolate MTB even though many patients remain infectious due to the presence of viable non-culturable forms. Previously, we have shown that two short cationic peptides, T14D and TB08L, induce a hormetic response at low concentrations, leading to a stimulation of growth in MTB and the related animal pathogen Mycobacterium bovis (bTB). Here, we examine these peptides showing they can influence the mycobacterial membrane integrity and function through membrane potential reduction. We also show this disruption is associated with an abnormal reduction in transcriptomic signalling from specific mycobacterial membrane sensors that normally monitor the immediate cellular environment and maintain the non-growing phenotype. We observe that exposing MTB or bTB to these peptides at optimal concentrations rapidly represses signalling mechanisms maintaining dormancy phenotypes, which leads to the promotion of aerobic metabolism and conversion into a replicative phenotype. We further show a practical application of these peptides as reagents able to enhance conventional routine culture methods by stimulating mycobacterial growth. We evaluated the ability of a peptide-supplemented sample preparation and culture protocol to isolate the MTB against a gold standard routine method tested in parallel on 255 samples from 155 patients with suspected TB. The peptide enhancement increased the sample positivity rate by 46% and decreased the average time to sample positivity of respiratory/faecal sampling by seven days. The most significant improvements in isolation rates were from sputum smear-negative low-load samples and faeces. The peptide enhancement increased sampling test sensitivity by 19%, recovery in samples from patients with a previously culture-confirmed TB by 20%, and those empirically treated for TB by 21%. We conclude that sample decontamination and culture enhancement with D-enantiomer peptides offer good potential for the much-needed improvement of the culture confirmation of TB.
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Affiliation(s)
- Tim J. Bull
- Institute of Infection and Immunity, St. George’s, University of London, Cranmer Terrace, London SW17 0RE, UK (K.H.)
| | - Tulika Munshi
- Institute of Infection and Immunity, St. George’s, University of London, Cranmer Terrace, London SW17 0RE, UK (K.H.)
| | | | - Andy C. Tran
- Institute of Infection and Immunity, St. George’s, University of London, Cranmer Terrace, London SW17 0RE, UK (K.H.)
| | - Catherine Cosgrove
- St. George’s Hospital NHS Trust, Cranmer Terrace, London SW17 0RE, UK; (C.C.)
| | - Angela Bartolf
- St. George’s Hospital NHS Trust, Cranmer Terrace, London SW17 0RE, UK; (C.C.)
| | - Melissa Menichini
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy (L.R.); (S.E.); (G.B.)
| | - Laura Rindi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy (L.R.); (S.E.); (G.B.)
| | - Lena Parigger
- Institute of Molecular Biosciences, Biophysics Division, University of Graz, Humboldstrasse 50/III, 800 Graz, Austria; (L.P.); (K.L.)
| | - Nermina Malanovic
- Institute of Molecular Biosciences, Biophysics Division, University of Graz, Humboldstrasse 50/III, 800 Graz, Austria; (L.P.); (K.L.)
| | - Karl Lohner
- Institute of Molecular Biosciences, Biophysics Division, University of Graz, Humboldstrasse 50/III, 800 Graz, Austria; (L.P.); (K.L.)
| | - Carl J. H. Wang
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia (A.F.); (L.L.M.)
| | - Anam Fatima
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia (A.F.); (L.L.M.)
| | - Lisandra L. Martin
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia (A.F.); (L.L.M.)
| | - Semih Esin
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy (L.R.); (S.E.); (G.B.)
| | - Giovanna Batoni
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy (L.R.); (S.E.); (G.B.)
| | - Kai Hilpert
- Institute of Infection and Immunity, St. George’s, University of London, Cranmer Terrace, London SW17 0RE, UK (K.H.)
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Hilpert K, Munshi T, López-Pérez PM, Sequeira-Garcia J, Hofmann S, Bull TJ. Discovery of Antimicrobial Peptides That Can Accelerate Culture Diagnostics of Slow-Growing Mycobacteria Including Mycobacterium tuberculosis. Microorganisms 2023; 11:2225. [PMID: 37764069 PMCID: PMC10536189 DOI: 10.3390/microorganisms11092225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 08/24/2023] [Accepted: 08/30/2023] [Indexed: 09/29/2023] Open
Abstract
Antimicrobial peptides (AMPs) can directly kill Gram-positive bacteria, Gram-negative bacteria, mycobacteria, fungi, enveloped viruses, and parasites. At sublethal concentrations, some AMPs and also conventional antibiotics can stimulate bacterial response increasing their resilience, also called the hormetic response. This includes stimulation of growth, mobility, and biofilm production. Here, we describe the discovery of AMPs that stimulate the growth of certain mycobacteria. Peptide 14 showed a growth stimulating effect on Mycobacteria tuberculosis (MTB), M. bovis, M. avium subsp. paratuberculosis (MAP), M. marinum, M. avium-intracellulare, M. celatum, and M. abscessus. The effect was more pronounced at low bacterial inocula. The peptides induce a faster transition from the lag phase to the log phase and keep the bacteria longer in the log phase before entering stationary phase when compared to nontreated controls. In some cases, an increase in the division rate was observed. An initial screen using MAP and a collection of 75 peptides revealed 13 peptides with a hormetic effect. For MTB, a collection of 25 artificial peptides were screened and 13 were found to reduce the time to positivity (TTP) by at least 5%, improving growth. A screen of 43 naturally occurring peptides, 11 fragments of naturally occurring peptides and 5 designed peptides, all taken from the database APD3, identified a further 44 peptides that also lowered TTP by at least 5%. Lasioglossin LL-III (Bee) and Ranacyclin E (Frog) were the most active natural peptides, and the human cathelicidin LL37 fragment GF-17 and a porcine cathelicidin protegrin-1 fragment were the most active fragments of naturally occurring peptides. Peptide 14 showed growth-stimulating activity between 10 ng/mL and 10 µg/mL, whereas the stability-optimised Peptide 14D had a narrow activity range of 0.1-1 µg/mL. Peptides identified in this study are currently in commercial use to improve recovery and culture for the diagnostics of mycobacteria in humans and animals.
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Affiliation(s)
- Kai Hilpert
- Institute of Infection and Immunity, St George’s, University of London, Cranmer Terrace, London SW17 0RE, UK (T.J.B.)
| | - Tulika Munshi
- Institute of Infection and Immunity, St George’s, University of London, Cranmer Terrace, London SW17 0RE, UK (T.J.B.)
| | | | | | - Sven Hofmann
- Institute of Infection and Immunity, St George’s, University of London, Cranmer Terrace, London SW17 0RE, UK (T.J.B.)
| | - Tim J. Bull
- Institute of Infection and Immunity, St George’s, University of London, Cranmer Terrace, London SW17 0RE, UK (T.J.B.)
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Hilpert K, Rumancev C, Gani J, Collis DWP, Lopez-Perez PM, Garamus VM, Mikut R, Rosenhahn A. Can BioSAXS detect ultrastructural changes of antifungal compounds in Candida albicans?-an exploratory study. Front Pharmacol 2023; 14:1141785. [PMID: 37533629 PMCID: PMC10393279 DOI: 10.3389/fphar.2023.1141785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 07/06/2023] [Indexed: 08/04/2023] Open
Abstract
The opportunistic yeast Candida albicans is the most common cause of candidiasis. With only four classes of antifungal drugs on the market, resistance is becoming a problem in the treatment of fungal infections, especially in immunocompromised patients. The development of novel antifungal drugs with different modes of action is urgent. In 2016, we developed a groundbreaking new medium-throughput method to distinguish the effects of antibacterial agents. Using small-angle X-ray scattering for biological samples (BioSAXS), it is now possible to screen hundreds of new antibacterial compounds and select those with the highest probability for a novel mode of action. However, yeast (eukaryotic) cells are highly structured compared to bacteria. The fundamental question to answer was if the ultrastructural changes induced by the action of an antifungal drug can be detected even when most structures in the cell stay unchanged. In this exploratory work, BioSAXS was used to measure the ultrastructural changes of C. albicans that were directly or indirectly induced by antifungal compounds. For this, the well-characterized antifungal drug Flucytosine was used. BioSAXS measurements were performed on the synchrotron P12 BioSAXS beamline, EMBL (DESY, Hamburg) on treated and untreated yeast C. albicans. BioSAXS curves were analysed using principal component analysis (PCA). The PCA showed that Flucytosine-treated and untreated yeast were separated. Based on that success further measurements were performed on five antifungal peptides {1. Cecropin A-melittin hybrid [CA (1-7) M (2-9)], KWKLFKKIGAVLKVL; 2. Lasioglossin LL-III, VNWKKILGKIIKVVK; 3. Mastoparan M, INLKAIAALAKKLL; 4. Bmkn2, FIGAIARLLSKIFGKR; and 5. optP7, KRRVRWIIW}. The ultrastructural changes of C. albicans indicate that the peptides may have different modes of action compared to Flucytosine as well as to each other, except for the Cecropin A-melittin hybrid [CA (1-7) M (2-9)] and optP7, showing very similar effects on C. albicans. This very first study demonstrates that BioSAXS shows promise to be used for antifungal drug development. However, this first study has limitations and further experiments are necessary to establish this application.
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Affiliation(s)
- Kai Hilpert
- Institute of Infection and Immunology, St. George’s, University of London (SGUL), London, United Kingdom
| | - Christoph Rumancev
- Laboratory Analytical Chemistry—Biointerfaces, Ruhr-University Bochum, Bochum, Germany
| | - Jurnorain Gani
- Institute of Infection and Immunology, St. George’s, University of London (SGUL), London, United Kingdom
| | | | | | | | - Ralf Mikut
- Institute for Automation and Applied Informatics (IAI), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Axel Rosenhahn
- Laboratory Analytical Chemistry—Biointerfaces, Ruhr-University Bochum, Bochum, Germany
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Rumancev C, Rosenhahn A, Hilpert K. BioSAXS–an emerging method to accelerate, enrich and de-risk antimicrobial drug development. Front Pharmacol 2022; 13:947005. [PMID: 36081947 PMCID: PMC9445215 DOI: 10.3389/fphar.2022.947005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 06/27/2022] [Indexed: 11/13/2022] Open
Abstract
Antimicrobial resistance is a worldwide threat to modern health care. Low-profit margin and high risk of cross-resistance resulted in a loss of interest in big pharma, contributing to the increasing threat. Strategies to address the problem are starting to emerge. Novel antimicrobial compounds with novel modes of action are especially valued because they have a lower risk of cross-resistance. Up to now determining the mode of action has been very time and resource consuming and will be performed once drug candidates were already progressed in preclinical development. BioSAXS is emerging as a new method to test up to thousands of compounds to classify them into groups based on ultra-structural changes that correlate to their modes of action. First experiments in E. coli (gram-negative) have demonstrated that using conventional and experimental antimicrobials a classification of compounds according to their mode of action was possible. Results were backed up by transmission electron microscopy. Further work showed that also gram-positive bacteria (Staphylococcus aureus) can be used and the effects of novel antimicrobial peptides on both types of bacteria were studied. Preliminary experiments also show that BioSAXS can be used to classify antifungal drugs, demonstrated on Candida albicans. In summary, BioSAXS can accelerate and enrich the discovery of antimicrobial compounds from screening projects with a novel mode of action and hence de-risk the development of urgently needed antimicrobial drugs.
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Affiliation(s)
- Christoph Rumancev
- Analytical Chemistry, Biointerfaces, Ruhr-University Bochum, Bochum, Germany
| | - Axel Rosenhahn
- Analytical Chemistry, Biointerfaces, Ruhr-University Bochum, Bochum, Germany
- *Correspondence: Axel Rosenhahn,
| | - Kai Hilpert
- Institute of Infection and Immunology, University of London, London, United Kingdom
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Oyama LB, Olleik H, Teixeira ACN, Guidini MM, Pickup JA, Hui BYP, Vidal N, Cookson AR, Vallin H, Wilkinson T, Bazzolli DMS, Richards J, Wootton M, Mikut R, Hilpert K, Maresca M, Perrier J, Hess M, Mantovani HC, Fernandez-Fuentes N, Creevey CJ, Huws SA. In silico identification of two peptides with antibacterial activity against multidrug-resistant Staphylococcus aureus. NPJ Biofilms Microbiomes 2022; 8:58. [PMID: 35835775 PMCID: PMC9283466 DOI: 10.1038/s41522-022-00320-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Accepted: 06/21/2022] [Indexed: 12/29/2022] Open
Abstract
Here we report two antimicrobial peptides (AMPs), HG2 and HG4 identified from a rumen microbiome metagenomic dataset, with activity against multidrug-resistant (MDR) bacteria, especially methicillin-resistant Staphylococcus aureus (MRSA) strains, a major hospital and community-acquired pathogen. We employed the classifier model design to analyse, visualise, and interpret AMP activities. This approach allowed in silico discrimination of promising lead AMP candidates for experimental evaluation. The lead AMPs, HG2 and HG4, are fast-acting and show anti-biofilm and anti-inflammatory activities in vitro and demonstrated little toxicity to human primary cell lines. The peptides were effective in vivo within a Galleria mellonella model of MRSA USA300 infection. In terms of mechanism of action, HG2 and HG4 appear to interact with the cytoplasmic membrane of target cells and may inhibit other cellular processes, whilst preferentially binding to bacterial lipids over human cell lipids. Therefore, these AMPs may offer additional therapeutic templates for MDR bacterial infections.
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Affiliation(s)
- Linda B. Oyama
- grid.4777.30000 0004 0374 7521Institute for Global Food Security, School of Biological Sciences, Queen’s University Belfast, 19 Chlorine Gardens, Belfast, Northern Ireland BT9 5DL UK
| | - Hamza Olleik
- grid.6227.10000000121892165CNRS Enzyme and Cell Engineering Laboratory, Université de Technologie de Compiègne, Sorbonne Universités, Rue du Docteur Schweitzer, CS 60319, CEDEX, 60203 Compiègne, France
| | - Ana Carolina Nery Teixeira
- grid.12799.340000 0000 8338 6359Departamento de Microbiologia, Universidade Federal de Viçosa, Viçosa, 36570-900 Brasil
| | - Matheus M. Guidini
- grid.12799.340000 0000 8338 6359Departamento de Microbiologia, Universidade Federal de Viçosa, Viçosa, 36570-900 Brasil
| | - James A. Pickup
- grid.4777.30000 0004 0374 7521Institute for Global Food Security, School of Biological Sciences, Queen’s University Belfast, 19 Chlorine Gardens, Belfast, Northern Ireland BT9 5DL UK
| | - Brandon Yeo Pei Hui
- University College Fairview (UCF), 4178, Jalan 1/27D, Section 6, Wangsa Maju, 53300 Kuala Lumpur, Malaysia
| | - Nicolas Vidal
- grid.5399.60000 0001 2176 4817Yelen Analytics, Aix-Marseille University ICR, 13013 Marseille, France
| | - Alan R. Cookson
- grid.8186.70000 0001 2168 2483Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, Wales SY23 3DA UK
| | - Hannah Vallin
- grid.8186.70000 0001 2168 2483Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, Wales SY23 3DA UK
| | - Toby Wilkinson
- grid.4305.20000 0004 1936 7988The Roslin Institute and R(D)SVS, University of Edinburgh, Edinburgh, United Kingdom
| | - Denise M. S. Bazzolli
- grid.12799.340000 0000 8338 6359Departamento de Microbiologia, Universidade Federal de Viçosa, Viçosa, 36570-900 Brasil
| | - Jennifer Richards
- grid.241103.50000 0001 0169 7725Specialist Antimicrobial Chemotherapy Unit, Public Health Wales, University Hospital of Wales, Heath Park, Cardiff, CF14 4XW UK
| | - Mandy Wootton
- grid.241103.50000 0001 0169 7725Specialist Antimicrobial Chemotherapy Unit, Public Health Wales, University Hospital of Wales, Heath Park, Cardiff, CF14 4XW UK
| | - Ralf Mikut
- grid.7892.40000 0001 0075 5874Karlsruhe Institute of Technology, Institute for Automation and Applied Informatics, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein, Leopoldshafen Germany
| | - Kai Hilpert
- grid.4464.20000 0001 2161 2573Institute of Infection and Immunity, St George’s, University of London, Cranmer Terrace, London, SW17 0RE UK
| | - Marc Maresca
- grid.5399.60000 0001 2176 4817Aix Marseille University, CNRS, Centrale Marseille, iSm2, Marseille, France
| | - Josette Perrier
- grid.5399.60000 0001 2176 4817Aix Marseille University, CNRS, Centrale Marseille, iSm2, Marseille, France
| | - Matthias Hess
- grid.27860.3b0000 0004 1936 9684UC Davis, College of Agricultural and Environmental Sciences, California, 95616 CA USA
| | - Hilario C. Mantovani
- grid.12799.340000 0000 8338 6359Departamento de Microbiologia, Universidade Federal de Viçosa, Viçosa, 36570-900 Brasil
| | - Narcis Fernandez-Fuentes
- grid.8186.70000 0001 2168 2483Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, Wales SY23 3DA UK
| | - Christopher J. Creevey
- grid.4777.30000 0004 0374 7521Institute for Global Food Security, School of Biological Sciences, Queen’s University Belfast, 19 Chlorine Gardens, Belfast, Northern Ireland BT9 5DL UK
| | - Sharon A. Huws
- grid.4777.30000 0004 0374 7521Institute for Global Food Security, School of Biological Sciences, Queen’s University Belfast, 19 Chlorine Gardens, Belfast, Northern Ireland BT9 5DL UK
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Hilpert K, Gani J, Rumancev C, Simpson N, Lopez-Perez PM, Garamus VM, von Gundlach AR, Markov P, Scocchi M, Mikut R, Rosenhahn A. Rational Designed Hybrid Peptides Show up to a 6-Fold Increase in Antimicrobial Activity and Demonstrate Different Ultrastructural Changes as the Parental Peptides Measured by BioSAXS. Front Pharmacol 2021; 12:769739. [PMID: 34966279 PMCID: PMC8711299 DOI: 10.3389/fphar.2021.769739] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 11/12/2021] [Indexed: 11/27/2022] Open
Abstract
Antimicrobial peptides (AMPs) are a promising class of compounds being developed against multi-drug resistant bacteria. Hybridization has been reported to increase antimicrobial activity. Here, two proline-rich peptides (consP1: VRKPPYLPRPRPRPL-CONH2 and Bac5-v291: RWRRPIRRRPIRPPFWR-CONH2) were combined with two arginine-isoleucine-rich peptides (optP1: KIILRIRWR-CONH2 and optP7: KRRVRWIIW-CONH2). Proline-rich antimicrobial peptides (PrAMPs) are known to inhibit the bacterial ribosome, shown also for Bac5-v291, whereas it is hypothesized a “dirty drug” model for the arginine-isoleucine-rich peptides. That hypothesis was underpinned by transmission electron microscopy and biological small-angle X-ray scattering (BioSAXS). The strength of BioSAXS is the power to detect ultrastructural changes in millions of cells in a short time (seconds) in a high-throughput manner. This information can be used to classify antimicrobial compounds into groups according to the ultrastructural changes they inflict on bacteria and how the bacteria react towards that assault. Based on previous studies, this correlates very well with different modes of action. Due to the novelty of this approach direct identification of the target of the antimicrobial compound is not yet fully established, more research is needed. More research is needed to address this limitation. The hybrid peptides showed a stronger antimicrobial activity compared to the proline-rich peptides, except when compared to Bac5-v291 against E. coli. The increase in activity compared to the arginine-isoleucine-rich peptides was up to 6-fold, however, it was not a general increase but was dependent on the combination of peptides and bacteria. BioSAXS experiments revealed that proline-rich peptides and arginine-isoleucine-rich peptides induce very different ultrastructural changes in E. coli, whereas a hybrid peptide (hyP7B5GK) shows changes, different to both parental peptides and the untreated control. These different ultrastructural changes indicated that the mode of action of the parental peptides might be different from each other as well as from the hybrid peptide hyP7B5GK. All peptides showed very low haemolytic activity, some of them showed a 100-fold or larger therapeutic window, demonstrating the potential for further drug development.
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Affiliation(s)
- Kai Hilpert
- Institute of Infection and Immunology, St. George's, University of London, London, United Kingdom
| | - Jurnorain Gani
- Institute of Infection and Immunology, St. George's, University of London, London, United Kingdom
| | - Christoph Rumancev
- Laboratory Analytical Chemistry - Biointerfaces, Ruhr University Bochum, Bochum, Germany
| | - Nathan Simpson
- Institute of Infection and Immunology, St. George's, University of London, London, United Kingdom
| | | | | | | | - Petar Markov
- European Molecular Biology Laboratory, Hamburg Outstation, Hamburg, Germany
| | - Marco Scocchi
- Department of Life Sciences, University of Trieste, Trieste, Italy
| | - Ralf Mikut
- Institute for Automation and Applied Informatics (IAI), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Axel Rosenhahn
- Laboratory Analytical Chemistry - Biointerfaces, Ruhr University Bochum, Bochum, Germany
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Hilpert K, Mikut R. Is There a Connection Between Gut Microbiome Dysbiosis Occurring in COVID-19 Patients and Post-COVID-19 Symptoms? Front Microbiol 2021; 12:732838. [PMID: 34603261 PMCID: PMC8485028 DOI: 10.3389/fmicb.2021.732838] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 08/13/2021] [Indexed: 01/07/2023] Open
Affiliation(s)
- Kai Hilpert
- Institute of Infection and Immunology, St George's, University of London, London, United Kingdom
| | - Ralf Mikut
- Institute for Automation and Applied Informatics (IAI), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
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Yu K, Alzahrani A, Khoddami S, Cheng JTJ, Mei Y, Gill A, Luo HD, Haney EF, Hilpert K, Hancock REW, Lange D, Kizhakkedathu JN. Rapid Assembly of Infection-Resistant Coatings: Screening and Identification of Antimicrobial Peptides Works in Cooperation with an Antifouling Background. ACS Appl Mater Interfaces 2021; 13:36784-36799. [PMID: 34328312 DOI: 10.1021/acsami.1c07515] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Bacterial adhesion and the succeeding biofilm formation onto surfaces are responsible for implant- and device-associated infections. Bifunctional coatings integrating both nonfouling components and antimicrobial peptides (AMPs) are a promising approach to develop potent antibiofilm coatings. However, the current approaches and chemistry for such coatings are time-consuming and dependent on substrates and involve a multistep process. Also, the information is limited on the influence of the coating structure or its components on the antibiofilm activity of such AMP-based coatings. Here, we report a new strategy to rapidly assemble a stable, potent, and substrate-independent AMP-based antibiofilm coating in a nonfouling background. The coating structure allowed for the screening of AMPs in a relevant nonfouling background to identify optimal peptide combinations that work in cooperation to generate potent antibiofilm activity. The structure of the coating was changed by altering the organization of the hydrophilic polymer chains within the coatings. The coatings were thoroughly characterized using various surface analytical techniques and correlated with the efficiency to prevent biofilm formation against diverse bacteria. The coating method that allowed the conjugation of AMPs without altering the steric protection ability of hydrophilic polymer structure results in a bifunctional surface coating with excellent antibiofilm activity. In contrast, the conjugation of AMPs directly to the hydrophilic polymer chains resulted in a surface with poor antibiofilm activity and increased adhesion of bacteria. Using this coating approach, we further established a new screening method and identified a set of potent surface-tethered AMPs with high activity. The success of this new peptide screening and coating method is demonstrated using a clinically relevant mouse infection model to prevent catheter-associated urinary tract infection (CAUTI).
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Affiliation(s)
- Kai Yu
- Centre for Blood Research and Department of Pathology & Laboratory Medicine, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Amal Alzahrani
- The Stone Centre at VGH, Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia V5Z 1M9, Canada
| | - Sara Khoddami
- The Stone Centre at VGH, Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia V5Z 1M9, Canada
| | - John T J Cheng
- Department of Microbiology and Immunology and Centre for Microbial Diseases and Immunity Research, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Yan Mei
- Centre for Blood Research and Department of Pathology & Laboratory Medicine, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Arshdeep Gill
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Haiming D Luo
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Evan F Haney
- Department of Microbiology and Immunology and Centre for Microbial Diseases and Immunity Research, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Kai Hilpert
- Institute of Infection and Immunology, St. George's University of London (SGUL), London SW17 0RE, United Kingdom
| | - Robert E W Hancock
- Department of Microbiology and Immunology and Centre for Microbial Diseases and Immunity Research, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Dirk Lange
- The Stone Centre at VGH, Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia V5Z 1M9, Canada
| | - Jayachandran N Kizhakkedathu
- Centre for Blood Research and Department of Pathology & Laboratory Medicine, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
- The School of Biomedical Engineering, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
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10
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Biggart M, Hilpert K, Tarren R, Baines D. Antimicrobial Activity Of A Histone Derived Peptide In The Airway Surface Liquid. FASEB J 2021. [DOI: 10.1096/fasebj.2021.35.s1.03655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Matthew Biggart
- Infection and Immunity Research InstituteSt George's University of LondonTooting
| | - Kai Hilpert
- Infection and Immunity Research InstituteSt George's University of LondonTooting
| | - Robert Tarren
- Cell Biology & PhysiologyUniversity of North Carolina, Chapel HillChapel HillNC
| | - Deborah Baines
- Infection and Immunity Research InstituteSt George's University of LondonTooting
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11
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Mardirossian M, Sola R, Beckert B, Valencic E, Collis DWP, Borišek J, Armas F, Di Stasi A, Buchmann J, Syroegin EA, Polikanov YS, Magistrato A, Hilpert K, Wilson DN, Scocchi M. Peptide Inhibitors of Bacterial Protein Synthesis with Broad Spectrum and SbmA-Independent Bactericidal Activity against Clinical Pathogens. J Med Chem 2020; 63:9590-9602. [PMID: 32787108 DOI: 10.1021/acs.jmedchem.0c00665] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Proline-rich antimicrobial peptides (PrAMPs) are promising lead compounds for developing new antimicrobials; however, their narrow spectrum of action is limiting. PrAMPs kill bacteria binding to their ribosomes and inhibiting protein synthesis. In this study, 133 derivatives of the PrAMP Bac7(1-16) were synthesized to identify the crucial residues for ribosome inactivation and antimicrobial activity. Then, five new Bac7(1-16) derivatives were conceived and characterized by antibacterial and membrane permeabilization assays, X-ray crystallography, and molecular dynamics simulations. Some derivatives displayed broad spectrum activity, encompassing Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa, and Staphylococcus aureus. Two peptides out of five acquired a weak membrane-perturbing activity while maintaining the ability to inhibit protein synthesis. These derivatives became independent of the SbmA transporter, commonly used by native PrAMPs, suggesting that they obtained a novel route to enter bacterial cells. PrAMP-derived compounds could become new-generation antimicrobials to combat antibiotic-resistant pathogens.
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Affiliation(s)
- Mario Mardirossian
- Department of Medical Sciences, University of Trieste, 34125 Trieste, Italy
| | - Riccardo Sola
- Department of Life Sciences, University of Trieste, 34127 Trieste, Italy
| | - Bertrand Beckert
- Institut für Biochemie und Molekularbiologie, University of Hamburg, 20146 Hamburg, Germany
| | - Erica Valencic
- Institute for Maternal and Child Health-IRCCS "Burlo Garofolo", 30137 Trieste, Italy
| | | | | | - Federica Armas
- Department of Life Sciences, University of Trieste, 34127 Trieste, Italy
| | - Adriana Di Stasi
- Department of Life Sciences, University of Trieste, 34127 Trieste, Italy
| | - Jan Buchmann
- Institut für Biochemie und Molekularbiologie, University of Hamburg, 20146 Hamburg, Germany.,Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois 60607, United States
| | - Egor A Syroegin
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois 60607, United States
| | - Yury S Polikanov
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois 60607, United States.,Department of Pharmaceutical Sciences, University of Illinois at Chicago, Chicago, Illinois 60607, United States
| | | | - Kai Hilpert
- Institute of Infection and Immunology, St. George's, University of London, SW 17 0RE London, U.K
| | - Daniel N Wilson
- Institut für Biochemie und Molekularbiologie, University of Hamburg, 20146 Hamburg, Germany
| | - Marco Scocchi
- Department of Life Sciences, University of Trieste, 34127 Trieste, Italy
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12
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Biggart MGS, Ling X, Simpson N, Gani J, Wrobel J, Hilpert K, Chen X, Tarran R, Baines D. Identification Of A Novel Histone Derived Antimicrobial Peptide In Airway Surface Liquid. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.02889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | - Nathan Simpson
- St George’s University Of London
- London School of Hygiene & Tropical Medicine
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13
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Grimsey E, Collis DWP, Mikut R, Hilpert K. The effect of lipidation and glycosylation on short cationic antimicrobial peptides. Biochim Biophys Acta Biomembr 2020; 1862:183195. [PMID: 32130974 DOI: 10.1016/j.bbamem.2020.183195] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 01/08/2020] [Accepted: 01/10/2020] [Indexed: 01/16/2023]
Abstract
The global health threat surrounding bacterial resistance has resulted in antibiotic researchers shifting their focus away from 'traditional' antibiotics and concentrating on other antimicrobial agents, including antimicrobial peptides. These low molecular weight "mini-proteins" exhibit broad-spectrum activity against bacteria, including multi-drug resistant strains, viruses, fungi and protozoa and constitute a major element of the innate-immune system of many multicellular organisms. Some naturally occurring antimicrobial peptides are lipidated and/or glycosylated and almost all antimicrobial peptides in clinical use are either lipopeptides (Daptomycin and Polymyxin E and B) or glycopeptides (Vancomycin). Lipidation, glycosylation and PEGylation are an option for improving stability and activity in serum and for reducing the rapid clearing via the kidneys and liver. Two broad-spectrum antimicrobial peptides NH2-RIRIRWIIR-CONH2 (A1) and NH2-KRRVRWIIW-CONH2 (B1) were conjugated via a linker, producing A2 and B2, to individual fatty acids of C8, C10, C12 and C14 and in addition, A2 was conjugated to either glucose, N-acetyl glucosamine, galactose, mannose, lactose or polyethylene glycol (PEG). Antimicrobial activity against two Gram-positive strains (methicillin resistant Staphylococcus aureus (MRSA) and vancomycin resistant Enterococcus faecalis (VRE)) and three Gram-negative strains (Salmonella typhimurium, E. coli and Pseudomonas aeruginosa) were determined. Activity patterns for the lipidated versions are very complex, dependent on sequence, bacteria and fatty acid. Two reciprocal effects were measured; compared to the parental peptides, some combinations led to a 16-fold improvement whereas other combinations let to a 32-fold reduction in antimicrobial activity. Glycosylation decreased antimicrobial activity by 2 to 16-fold in comparison to A1, respectively on the sugar-peptide combination. PEGylation rendered the peptide inactive. Antimicrobial activity in the presence of 25% human serum of A1 and B1 was reduced 32-fold and 8-fold, respectively. The longer chain fatty acids almost completely restored this activity; however, these fatty acids increased hemolytic activity. B1 modified with C8 increased the therapeutic index by 2-fold for four bacterial strains. Our results suggest that finding the right lipid-peptide combination can lead to improved activity in the presence of serum and potentially more effective drug candidates for animal studies. Glycosylation with the optimal sugar and numbers of sugars at the right peptide position could be an alternative route or could be used in addition to lipidation to counteract solubility and toxicity issues.
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Affiliation(s)
- Elizabeth Grimsey
- Institute for Infection and Immunity, St. George's University of London, London, UK
| | | | - Ralf Mikut
- Karlsruhe Institute of Technology (KIT), Institute for Automation and Applied Informatics (IAI), Eggenstein-Leopoldshafen, Germany
| | - Kai Hilpert
- Institute for Infection and Immunity, St. George's University of London, London, UK.
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14
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Mardirossian M, Sola R, Beckert B, Collis DWP, Di Stasi A, Armas F, Hilpert K, Wilson DN, Scocchi M. Proline-Rich Peptides with Improved Antimicrobial Activity against E. coli, K. pneumoniae, and A. baumannii. ChemMedChem 2019; 14:2025-2033. [PMID: 31692278 PMCID: PMC6973051 DOI: 10.1002/cmdc.201900465] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 10/16/2019] [Indexed: 01/08/2023]
Abstract
Proline-rich antimicrobial peptides (PrAMPs) are promising agents to combat multi-drug resistant pathogens due to a high antimicrobial activity, yet low cytotoxicity. A library of derivatives of the PrAMP Bac5(1-17) was synthesized and screened to identify which residues are relevant for its activity. In this way, we discovered that two central motifs -PIRXP- cannot be modified, while residues at N- and C- termini tolerated some variations. We found five Bac5(1-17) derivatives bearing 1-5 substitutions, with an increased number of arginine and/or tryptophan residues, exhibiting improved antimicrobial activity and broader spectrum of activity while retaining low cytotoxicity toward eukaryotic cells. Transcription/translation and bacterial membrane permeabilization assays showed that these new derivatives still retained the ability to strongly inhibit bacterial protein synthesis, but also acquired permeabilizing activity to different degrees. These new Bac5(1-17) derivatives therefore show a dual mode of action which could hinder the selection of bacterial resistance against these molecules.
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Affiliation(s)
| | - Riccardo Sola
- Department of Life SciencesUniversity of Trieste34128TriesteItaly
| | - Bertrand Beckert
- Institute for Biochemistry and Molecular BiologyUniversity of Hamburg20146HamburgGermany
| | | | - Adriana Di Stasi
- Department of Life SciencesUniversity of Trieste34128TriesteItaly
| | - Federica Armas
- Department of Life SciencesUniversity of Trieste34128TriesteItaly
| | - Kai Hilpert
- St GeorgesUniversity of LondonLondonSW17 0REUK
| | - Daniel N. Wilson
- Institute for Biochemistry and Molecular BiologyUniversity of Hamburg20146HamburgGermany
| | - Marco Scocchi
- Department of Life SciencesUniversity of Trieste34128TriesteItaly
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15
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Mardirossian M, Sola R, Beckert B, Collis DWP, Di Stasi A, Armas F, Hilpert K, Wilson DN, Scocchi M. Front Cover: Proline‐Rich Peptides with Improved Antimicrobial Activity against
E. coli
,
K. pneumoniae
, and
A. baumannii
(ChemMedChem 24/2019). ChemMedChem 2019. [DOI: 10.1002/cmdc.201900670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
| | - Riccardo Sola
- Department of Life SciencesUniversity of Trieste 34128 Trieste Italy
| | - Bertrand Beckert
- Institute for Biochemistry and Molecular BiologyUniversity of Hamburg 20146 Hamburg Germany
| | | | - Adriana Di Stasi
- Department of Life SciencesUniversity of Trieste 34128 Trieste Italy
| | - Federica Armas
- Department of Life SciencesUniversity of Trieste 34128 Trieste Italy
| | - Kai Hilpert
- St GeorgesUniversity of London London SW17 0RE UK
| | - Daniel N. Wilson
- Institute for Biochemistry and Molecular BiologyUniversity of Hamburg 20146 Hamburg Germany
| | - Marco Scocchi
- Department of Life SciencesUniversity of Trieste 34128 Trieste Italy
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16
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Ruden S, Rieder A, Chis Ster I, Schwartz T, Mikut R, Hilpert K. Synergy Pattern of Short Cationic Antimicrobial Peptides Against Multidrug-Resistant Pseudomonas aeruginosa. Front Microbiol 2019; 10:2740. [PMID: 31849888 PMCID: PMC6901909 DOI: 10.3389/fmicb.2019.02740] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 11/11/2019] [Indexed: 12/18/2022] Open
Abstract
With the rise of various multidrug-resistant (MDR) pathogenic bacteria, worldwide health care is under pressure to respond. Conventional antibiotics are failing and the development of novel classes and alternative strategies is a major priority. Antimicrobial peptides (AMPs) cannot only kill MDR bacteria, but also can be used synergistically with conventional antibiotics. We selected 30 short AMPs from different origins and measured their synergy in combination with polymyxin B, piperacillin, ceftazidime, cefepime, meropenem, imipenem, tetracycline, erythromycin, kanamycin, tobramycin, amikacin, gentamycin, and ciprofloxacin. In total, 403 unique combinations were tested against an MDR Pseudomonas aeruginosa isolate (PA910). As a measure of the synergistic effects, fractional inhibitory concentrations (FICs) were determined using microdilution assays with FICs ranges between 0.25 and 2. A high number of combinations between peptides and polymyxin B, erythromycin, and tetracycline were found to be synergistic. Novel variants of indolicidin also showed a high frequency in synergist interaction. Single amino acid substitutions within the peptides can have a very strong effect on the ability to synergize, making it possible to optimize future drugs toward synergistic interaction.
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Affiliation(s)
- Serge Ruden
- Institute of Biological Interfaces, Karlsruhe Institute of Technology, Karlsruhe, Germany.,Institute of Functional Interfaces, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Annika Rieder
- Institute of Functional Interfaces, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Irina Chis Ster
- Institute of Infection and Immunity, St George's, University of London, London, United Kingdom
| | - Thomas Schwartz
- Institute of Functional Interfaces, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Ralf Mikut
- Institute for Automation and Applied Informatics, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Kai Hilpert
- Institute of Functional Interfaces, Karlsruhe Institute of Technology, Karlsruhe, Germany.,Institute of Infection and Immunity, St George's, University of London, London, United Kingdom.,Institute of Microstructure Technology, Karlsruhe Institute of Technology, Karlsruhe, Germany
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17
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von Gundlach A, Ashby MP, Gani J, Lopez-Perez PM, Cookson AR, Ann Huws S, Rumancev C, Garamus VM, Mikut R, Rosenhahn A, Hilpert K. BioSAXS Measurements Reveal That Two Antimicrobial Peptides Induce Similar Molecular Changes in Gram-Negative and Gram-Positive Bacteria. Front Pharmacol 2019; 10:1127. [PMID: 31616307 PMCID: PMC6775230 DOI: 10.3389/fphar.2019.01127] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 08/30/2019] [Indexed: 01/10/2023] Open
Abstract
Two highly active short broad-spectrum AMPs (14D and 69D) with unknown mode of action have been investigated in regards to their effect against the Gram-negative bacteria Escherichia coli and the Gram-positive bacteria methicillin-resistant Staphylococcus aureus (MRSA). Minimal inhibitory concentration (MIC) measurements using a cell density of 108 cfu/ml resulted in values between 16 and 32 µg/ml. Time-kill experiments using 108 cfu/ml revealed complete killing, except for 69D in combination with MRSA, where bacterial load was reduced a million times. Small-angle X-ray scattering of biological samples (BioSAXS) at 108 cfu/ml was applied to investigate the ultrastructural changes in E. coli and MRSA in response to these two broad-spectrum AMPs. In addition, electron microscopy (EM) was performed to visualize the treated and non-treated bacteria. As expected, the scattering curves generated using BioSAXS show the ultrastructure of the Gram-positive and Gram-negative bacteria to be very different (BioSAXS is not susceptible to the outer shape). After treatment with either peptide, the scattering curves of E. coli and MRSA cells are much more alike. Whereas in EM, it is notoriously difficult to observe changes for spherical Gram-positives; the BioSAXS results are superior and reveal strongly similar effects for both peptides induced in Gram-positive as well as Gram-negative bacteria. Given the high-throughput possibility and robust statistics, BioSAXS can support and speed up mode of action research in AMPs and other antimicrobial compounds, making a contribution toward the development of urgently needed drugs against resistant bacteria.
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Affiliation(s)
| | - Martin P Ashby
- Institute of Infection and Immunology, St. George's University of London (SGUL), London, United Kingdom
| | - Jurnorain Gani
- Institute of Infection and Immunology, St. George's University of London (SGUL), London, United Kingdom
| | | | - Alan Roy Cookson
- Institute of Biological, Environmental & Rural Sciences (IBERS), Aberystwyth University, Aberystwyth, United Kingdom
| | - Sharon Ann Huws
- Institute of Global Food Security, School of Biological Sciences, Queens University Belfast, Medical Biology Centre, Belfast, United Kingdom
| | - Christoph Rumancev
- Analytical Chemistry - Biointerfaces, Ruhr-University Bochum, Bochum, Germany
| | - Vasil M Garamus
- Helmholtz-Zentrum Geesthacht, Zentrum für Material- und Küstenforschung GmbH, Geesthacht, Germany
| | - Ralf Mikut
- Institute for Automation and Applied Informatics (IAI), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Axel Rosenhahn
- Analytical Chemistry - Biointerfaces, Ruhr-University Bochum, Bochum, Germany
| | - Kai Hilpert
- Institute of Infection and Immunology, St. George's University of London (SGUL), London, United Kingdom
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18
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Thomas B, Gani J, Creevey C, Hilpert K. The Savage Dawn Peptide: an antibiotic woven from 12th century Welsh poetry. Access Microbiol 2019. [DOI: 10.1099/acmi.ac2019.po0559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Benjamin Thomas
- 2Queen’s University, Belfast, United Kingdom
- 1Aberystwyth University, Aberystwyth, United Kingdom
| | | | | | - Kai Hilpert
- 3St. George’s Hospital, London, United Kingdom
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19
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Oyama L, Olleik H, Carolina Nery Teixeira A, Guidini MM, Pickup JA, Cookson AR, Vallin H, Wilkinson T, Bazzolli D, Richards J, Wootton M, Mikut R, Hilpert K, Maresca M, Perrier J, Hess M, Mantovani HC, Fernandez-Fuentes N, Creevey CJ, Huws SA. In silico identification of two novel antimicrobial peptides with antibacterial activity against multi-drug resistant Staphylococcus aureus. Access Microbiol 2019. [DOI: 10.1099/acmi.ac2019.po0240] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Linda Oyama
- 1Queen’s University Belfast, Belfast, United Kingdom
| | | | | | | | | | | | - Hannah Vallin
- 4Aberystwyth University, Aberystwyth, United Kingdom
| | | | | | | | | | - Ralf Mikut
- 7Karlsruhe Institute of Technology, Leopoldshafen, Germany
| | - Kai Hilpert
- 8St. George’s University of London, London, United Kingdom
| | | | | | - Matthias Hess
- 10UC Davis, College of Agricultural and Environmental Sciences, California, USA
| | | | | | | | - Sharon A Huws
- 1Queen’s University Belfast, Belfast, United Kingdom
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20
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Mardirossian M, Pérébaskine N, Benincasa M, Gambato S, Hofmann S, Huter P, Müller C, Hilpert K, Innis CA, Tossi A, Wilson DN. The Dolphin Proline-Rich Antimicrobial Peptide Tur1A Inhibits Protein Synthesis by Targeting the Bacterial Ribosome. Cell Chem Biol 2018; 25:530-539.e7. [PMID: 29526712 PMCID: PMC6219704 DOI: 10.1016/j.chembiol.2018.02.004] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2017] [Revised: 01/08/2018] [Accepted: 02/05/2018] [Indexed: 12/22/2022]
Abstract
Proline-rich antimicrobial peptides (PrAMPs) internalize into susceptible bacteria using specific transporters and interfere with protein synthesis and folding. To date, mammalian PrAMPs have so far been identified only in artiodactyls. Since cetaceans are co-phyletic with artiodactyls, we mined the genome of the bottlenose dolphin Tursiops truncatus, leading to the identification of two PrAMPs, Tur1A and Tur1B. Tur1A, which is orthologous to the bovine PrAMP Bac7, is internalized into Escherichia coli, without damaging the membranes, using the inner membrane transporters SbmA and YjiL/MdM. Furthermore, like Bac7, Tur1A also inhibits bacterial protein synthesis by binding to the ribosome and blocking the transition from the initiation to the elongation phase. By contrast, Tur1B is a poor inhibitor of protein synthesis and may utilize another mechanism of action. An X-ray structure of Tur1A bound within the ribosomal exit tunnel provides a basis to develop these peptides as novel antimicrobial agents.
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Affiliation(s)
- Mario Mardirossian
- Gene Center, Department for Biochemistry and Center for Integrated Protein Sciences, Munich (CiPSM), University of Munich, 81377 Munich, Germany
| | - Natacha Pérébaskine
- ARNA Laboratory, University of Bordeaux, Inserm U1212, CNRS UMR 5320, IECB, 33607 Pessac, France
| | - Monica Benincasa
- Antimicrobial Peptides Laboratory, Department of Life Sciences, University of Trieste, 34127 Trieste, Italy
| | - Stefano Gambato
- Antimicrobial Peptides Laboratory, Department of Life Sciences, University of Trieste, 34127 Trieste, Italy
| | - Sven Hofmann
- Institute of Infection and Immunity, St George's, University of London, SW17 0RE London, UK
| | - Paul Huter
- Gene Center, Department for Biochemistry and Center for Integrated Protein Sciences, Munich (CiPSM), University of Munich, 81377 Munich, Germany; Institute for Biochemistry and Molecular Biology, University of Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg, Germany
| | - Claudia Müller
- Gene Center, Department for Biochemistry and Center for Integrated Protein Sciences, Munich (CiPSM), University of Munich, 81377 Munich, Germany; Institute for Biochemistry and Molecular Biology, University of Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg, Germany
| | - Kai Hilpert
- Institute of Infection and Immunity, St George's, University of London, SW17 0RE London, UK
| | - C Axel Innis
- ARNA Laboratory, University of Bordeaux, Inserm U1212, CNRS UMR 5320, IECB, 33607 Pessac, France
| | - Alessandro Tossi
- Antimicrobial Peptides Laboratory, Department of Life Sciences, University of Trieste, 34127 Trieste, Italy
| | - Daniel N Wilson
- Gene Center, Department for Biochemistry and Center for Integrated Protein Sciences, Munich (CiPSM), University of Munich, 81377 Munich, Germany; Institute for Biochemistry and Molecular Biology, University of Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg, Germany.
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21
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Oyama LB, Girdwood SE, Cookson AR, Fernandez-Fuentes N, Privé F, Vallin HE, Wilkinson TJ, Golyshin PN, Golyshina OV, Mikut R, Hilpert K, Richards J, Wootton M, Edwards JE, Maresca M, Perrier J, Lundy FT, Luo Y, Zhou M, Hess M, Mantovani HC, Creevey CJ, Huws SA. The rumen microbiome: an underexplored resource for novel antimicrobial discovery. NPJ Biofilms Microbiomes 2017; 3:33. [PMID: 29214045 PMCID: PMC5711939 DOI: 10.1038/s41522-017-0042-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 10/04/2017] [Accepted: 11/06/2017] [Indexed: 12/27/2022] Open
Abstract
Antimicrobial peptides (AMPs) are promising drug candidates to target multi-drug resistant bacteria. The rumen microbiome presents an underexplored resource for the discovery of novel microbial enzymes and metabolites, including AMPs. Using functional screening and computational approaches, we identified 181 potentially novel AMPs from a rumen bacterial metagenome. Here, we show that three of the selected AMPs (Lynronne-1, Lynronne-2 and Lynronne-3) were effective against numerous bacterial pathogens, including methicillin-resistant Staphylococcus aureus (MRSA). No decrease in MRSA susceptibility was observed after 25 days of sub-lethal exposure to these AMPs. The AMPs bound preferentially to bacterial membrane lipids and induced membrane permeability leading to cytoplasmic leakage. Topical administration of Lynronne-1 (10% w/v) to a mouse model of MRSA wound infection elicited a significant reduction in bacterial counts, which was comparable to treatment with 2% mupirocin ointment. Our findings indicate that the rumen microbiome may provide viable alternative antimicrobials for future therapeutic application. Anti-microbial molecules made by microbes in the gut of ruminant animals could become new weapons against antibiotic-resistant infections. An international team of researchers led by Sharon Huws at Queen’s University Belfast, UK, identified three anti-microbial peptides in the rumen of animals such as cattle, sheep and goats. The peptides—short proteins—were highly active in laboratory trials against several clinically important drug-resistant infections. These included methicillin resistant Staphylococcus aureus (MRSA), a notorious cause of life-threatening infections, especially in patients with weakened immunity. There is growing interest in using peptides as alternatives to existing antibiotics. The findings, initiated by examining a ‘library’ of molecular data, suggest that the rumen is an under-explored resource that may harbor many medically useful antimicrobials. The possibilities should be investigated further, with promising molecules being tested in clinical conditions.
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Affiliation(s)
- Linda B Oyama
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, Wales, SY23 3DA UK
| | - Susan E Girdwood
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, Wales, SY23 3DA UK
| | - Alan R Cookson
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, Wales, SY23 3DA UK
| | - Narcis Fernandez-Fuentes
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, Wales, SY23 3DA UK
| | - Florence Privé
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, Wales, SY23 3DA UK
| | - Hannah E Vallin
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, Wales, SY23 3DA UK
| | - Toby J Wilkinson
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, Wales, SY23 3DA UK
| | | | | | - Ralf Mikut
- Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein, Leopoldshafen, Germany
| | - Kai Hilpert
- Institute of Infection and Immunity, St. George's University of London, Cranmer Terrace, London, SW17 0RE UK
| | - Jennifer Richards
- Specialist Antimicrobial Chemotherapy Unit, Public Health Wales, University Hospital of Wales, Heath Park, Cardiff, CF14 4XW UK
| | - Mandy Wootton
- Specialist Antimicrobial Chemotherapy Unit, Public Health Wales, University Hospital of Wales, Heath Park, Cardiff, CF14 4XW UK
| | - Joan E Edwards
- Wageningen University & Research, 6708 WE, Wageningen, Netherlands
| | - Marc Maresca
- Aix Marseille Université, CNRS, Central Marseille, iSm2, Marseille, France
| | - Josette Perrier
- Aix Marseille Université, CNRS, Central Marseille, iSm2, Marseille, France
| | - Fionnuala T Lundy
- Centre for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, Northern Ireland, BT9 7BL UK
| | - Yu Luo
- Centre for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, Northern Ireland, BT9 7BL UK
| | - Mei Zhou
- School of Pharmacy, Queens's University Belfast, Belfast, BT9 7BL, Northern Ireland, UK
| | - Matthias Hess
- UC Davis, College of Agricultural and Environmental Sciences, California, 95616 USA
| | - Hilario C Mantovani
- Department of Microbiology, Universidade Federal de Viçosa, Viçosa, 36570-900 Brazil
| | - Christopher J Creevey
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, Wales, SY23 3DA UK
| | - Sharon A Huws
- Institute for Global Food Security, School of Biological Sciences, Medical Biology Centre, Queen's University Belfast, 97 Lisburn Road, Belfast, Northern Ireland, BT9 7BL UK
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22
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Oyama LB, Crochet JA, Edwards JE, Girdwood SE, Cookson AR, Fernandez-Fuentes N, Hilpert K, Golyshin PN, Golyshina OV, Privé F, Hess M, Mantovani HC, Creevey CJ, Huws SA. Buwchitin: A Ruminal Peptide with Antimicrobial Potential against Enterococcus faecalis. Front Chem 2017; 5:51. [PMID: 28748180 PMCID: PMC5506224 DOI: 10.3389/fchem.2017.00051] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 06/27/2017] [Indexed: 11/14/2022] Open
Abstract
Antimicrobial peptides (AMPs) are gaining popularity as alternatives for treatment of bacterial infections and recent advances in omics technologies provide new platforms for AMP discovery. We sought to determine the antibacterial activity of a novel antimicrobial peptide, buwchitin, against Enterococcus faecalis. Buwchitin was identified from a rumen bacterial metagenome library, cloned, expressed and purified. The antimicrobial activity of the recombinant peptide was assessed using a broth microdilution susceptibility assay to determine the peptide's killing kinetics against selected bacterial strains. The killing mechanism of buwchitin was investigated further by monitoring its ability to cause membrane depolarization (diSC3(5) method) and morphological changes in E. faecalis cells. Transmission electron micrographs of buwchitin treated E. faecalis cells showed intact outer membranes with blebbing, but no major damaging effects and cell morphology changes. Buwchitin had negligible cytotoxicity against defibrinated sheep erythrocytes. Although no significant membrane leakage and depolarization was observed, buwchitin at minimum inhibitory concentration (MIC) was bacteriostatic against E. faecalis cells and inhibited growth in vitro by 70% when compared to untreated cells. These findings suggest that buwchitin, a rumen derived peptide, has potential for antimicrobial activity against E. faecalis.
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Affiliation(s)
- Linda B Oyama
- Institute of Biological Environmental and Rural Sciences, Aberystwyth UniversityAberystwyth, United Kingdom
| | - Jean-Adrien Crochet
- Institute of Biological Environmental and Rural Sciences, Aberystwyth UniversityAberystwyth, United Kingdom
| | - Joan E Edwards
- Institute of Biological Environmental and Rural Sciences, Aberystwyth UniversityAberystwyth, United Kingdom
| | - Susan E Girdwood
- Institute of Biological Environmental and Rural Sciences, Aberystwyth UniversityAberystwyth, United Kingdom
| | - Alan R Cookson
- Institute of Biological Environmental and Rural Sciences, Aberystwyth UniversityAberystwyth, United Kingdom
| | - Narcis Fernandez-Fuentes
- Institute of Biological Environmental and Rural Sciences, Aberystwyth UniversityAberystwyth, United Kingdom
| | - Kai Hilpert
- Institute of Infection and Immunity, St George's University of LondonLondon, United Kingdom
| | - Peter N Golyshin
- School of Biological Sciences, Bangor UniversityBangor, United Kingdom
| | - Olga V Golyshina
- School of Biological Sciences, Bangor UniversityBangor, United Kingdom
| | - Florence Privé
- Institute of Biological Environmental and Rural Sciences, Aberystwyth UniversityAberystwyth, United Kingdom
| | - Matthias Hess
- College of Agricultural and Environmental Sciences, University of California, DavisDavis, CA, United States
| | | | - Christopher J Creevey
- Institute of Biological Environmental and Rural Sciences, Aberystwyth UniversityAberystwyth, United Kingdom
| | - Sharon A Huws
- Medical Biology Centre, School of Biological Sciences, Queen's University BelfastBelfast, United Kingdom
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23
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Hilpert K, Odoj R, Nürnberg HW. Mass Spectrometric Study of the Potential of Al2O3/SiO2Additives for the Retention of Cesium in Coated Particles. NUCL TECHNOL 2017. [DOI: 10.13182/nt83-a33144] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- K. Hilpert
- Nuclear Research Center Jülich, Institute of Applied Physical Chemistry Postfach 1913, D-5170 Jülich, Federal Republic of Germany
| | - R. Odoj
- Nuclear Research Center Jülich, Institute of Applied Physical Chemistry Postfach 1913, D-5170 Jülich, Federal Republic of Germany
| | - H. W. Nürnberg
- Nuclear Research Center Jülich, Institute of Applied Physical Chemistry Postfach 1913, D-5170 Jülich, Federal Republic of Germany
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24
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López-Pérez PM, Grimsey E, Bourne L, Mikut R, Hilpert K. Screening and Optimizing Antimicrobial Peptides by Using SPOT-Synthesis. Front Chem 2017; 5:25. [PMID: 28447030 PMCID: PMC5388751 DOI: 10.3389/fchem.2017.00025] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 03/29/2017] [Indexed: 11/14/2022] Open
Abstract
Peptide arrays on cellulose are a powerful tool to investigate peptide interactions with a number of different molecules, for examples antibodies, receptors or enzymes. Such peptide arrays can also be used to study interactions with whole cells. In this review, we focus on the interaction of small antimicrobial peptides with bacteria. Antimicrobial peptides (AMPs) can kill multidrug-resistant (MDR) human pathogenic bacteria and therefore could be next generation antibiotics targeting MDR bacteria. We describe the screen and the result of different optimization strategies of peptides cleaved from the membrane. In addition, screening of antibacterial activity of peptides that are tethered to the surface is discussed. Surface-active peptides can be used to protect surfaces from bacterial infections, for example implants.
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Affiliation(s)
| | - Elizabeth Grimsey
- Institute for Infection and Immunity, St. George's University of LondonLondon, UK
| | - Luc Bourne
- Institute for Infection and Immunity, St. George's University of LondonLondon, UK
| | - Ralf Mikut
- Karlsruhe Institute of Technology (KIT), Institute for Applied Computer Science (IAI)Eggenstein-Leopoldshafen, Germany
| | - Kai Hilpert
- TiKa Diagnostics LtdLondon, UK.,Institute for Infection and Immunity, St. George's University of LondonLondon, UK
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25
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Ashby M, Petkova A, Gani J, Mikut R, Hilpert K. Use of Peptide Libraries for Identification and Optimization of Novel Antimicrobial Peptides. Curr Top Med Chem 2017; 17:537-553. [PMID: 27411326 DOI: 10.2174/1568026616666160713125555] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 11/02/2015] [Accepted: 11/14/2015] [Indexed: 11/22/2022]
Abstract
The increasing rates of resistance among bacteria and to a lesser extent fungi have resulted in an urgent need to find new molecules that hold therapeutic promise against multidrug-resistant strains. Antimicrobial peptides have proven very effective against a variety of multidrug-resistant bacteria. Additionally, the low levels of resistance reported towards these molecules are an attractive feature for antimicrobial drug development. Here we summarise information on diverse peptide libraries used to discover or to optimize antimicrobial peptides. Chemical synthesized peptide libraries, for example split and mix method, tea bag method, multi-pin method and cellulose spot method are discussed. In addition biological peptide library screening methods are summarized, like phage display, bacterial display, mRNA-display and ribosomal display. A few examples are given for small peptide libraries, which almost exclusively follow a rational design of peptides of interest rather than a combinatorial approach.
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Affiliation(s)
| | | | | | | | - Kai Hilpert
- Institute of Infection and Immunity, St George's University of London, Jenner Wing, Second floor, Room 2.215C, Cranmer Terrace, London, SW17 0RE, UK
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26
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Bull TJ, Munshi T, Mikkelsen H, Hartmann SB, Sørensen MR, Garcia JS, Lopez-Perez PM, Hofmann S, Hilpert K, Jungersen G. Improved Culture Medium (TiKa) for Mycobacterium avium Subspecies Paratuberculosis (MAP) Matches qPCR Sensitivity and Reveals Significant Proportions of Non-viable MAP in Lymphoid Tissue of Vaccinated MAP Challenged Animals. Front Microbiol 2017; 7:2112. [PMID: 28101082 PMCID: PMC5209360 DOI: 10.3389/fmicb.2016.02112] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2016] [Accepted: 12/14/2016] [Indexed: 11/13/2022] Open
Abstract
The quantitative detection of viable pathogen load is an important tool in determining the degree of infection in animals and contamination of foodstuffs. Current conventional culture methods are limited in their ability to determine these levels in Mycobacterium avium subspecies paratuberculosis (MAP) due to slow growth, clumping and low recoverability issues. The principle goal of this study was to evaluate a novel culturing process (TiKa) with unique ability to stimulate MAP growth from low sample loads and dilutions. We demonstrate it was able to stimulate a mean 29-fold increase in recoverability and an improved sensitivity of up to three logs when compared with conventional culture. Using TiKa culture, MAP clumping was minimal and produced visible colonies in half the time required by standard culture methods. Parallel quantitative evaluation of the TiKa culture approach and qPCR on MAP loads in tissue and gut mucosal samples from a MAP vaccine-challenge study, showed good correlations between colony counts (cfu) and qPCR derived genome equivalents (Geq) over a large range of loads with a 30% greater sensitivity for TiKa culture approach at low loads (two logs). Furthermore, the relative fold changes in Geq and cfu from the TiKa culture approach suggests that non-mucosal tissue loads from MAP infected animals contained a reduced proportion of non-viable MAP (mean 19-fold) which was reduced significantly further (mean 190-fold) in vaccinated “reactor” calves. This study shows TiKa culture equates well with qPCR and provides important evidence that accuracy in estimating viable MAP load using DNA tests alone may vary significantly between samples of mucosal and lymphatic origin.
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Affiliation(s)
- Tim J Bull
- Institute of Infection and Immunity, St George's University of London London, UK
| | - Tulika Munshi
- Institute of Infection and Immunity, St George's University of London London, UK
| | - Heidi Mikkelsen
- National Veterinary Institute, Technical University of Denmark (DTU) Kongens Lyngby, Denmark
| | - Sofie B Hartmann
- National Veterinary Institute, Technical University of Denmark (DTU) Kongens Lyngby, Denmark
| | - Maria R Sørensen
- National Veterinary Institute, Technical University of Denmark (DTU) Kongens Lyngby, Denmark
| | - Joanna S Garcia
- Institute of Infection and Immunity, St George's University of London London, UK
| | - Paula M Lopez-Perez
- Institute of Infection and Immunity, St George's University of London London, UK
| | - Sven Hofmann
- Institute of Infection and Immunity, St George's University of London London, UK
| | - Kai Hilpert
- Institute of Infection and Immunity, St George's University of London London, UK
| | - Gregers Jungersen
- National Veterinary Institute, Technical University of Denmark (DTU) Kongens Lyngby, Denmark
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27
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von Gundlach AR, Garamus VM, Willey TM, Ilavsky J, Hilpert K, Rosenhahn A. Use of small-angle X-ray scattering to resolve intracellular structure changes of Escherichia coli cells induced by antibiotic treatment. J Appl Crystallogr 2016; 49:2210-2216. [PMID: 27980516 PMCID: PMC5139998 DOI: 10.1107/s1600576716018562] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 11/19/2016] [Indexed: 12/22/2022] Open
Abstract
The application of small-angle X-ray scattering (SAXS) to whole Escherichia coli cells is challenging owing to the variety of internal constituents. To resolve their contributions, the outer shape was captured by ultra-small-angle X-ray scattering and combined with the internal structure resolved by SAXS. Building on these data, a model for the major structural components of E. coli was developed. It was possible to deduce information on the occupied volume, occurrence and average size of the most important intracellular constituents: ribosomes, DNA and proteins. E. coli was studied after treatment with three different antibiotic agents (chloramphenicol, tetracycline and rifampicin) and the impact on the intracellular constituents was monitored.
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Affiliation(s)
- A. R. von Gundlach
- Analytical Chemistry – Biointerfaces, Ruhr-University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - V. M. Garamus
- Helmholtz-Zentrum Geesthacht, Zentrum für Material- und Küstenforschung GmbH, Max-Planck-Strasse 1, 21502 Geesthacht, Germany
| | - T. M. Willey
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550, USA
| | - J. Ilavsky
- X-ray Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA
| | - K. Hilpert
- Institute of Infection and Immunity, St George’s University of London (SGUL), Cranmer Terrace, London SW17 0RE, UK
| | - A. Rosenhahn
- Analytical Chemistry – Biointerfaces, Ruhr-University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
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28
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Abstract
Epithelial senescence is a complex process depending on intrinsic as well as extrinsic factors (e.g., UV or IR light, tobacco smoke) and must be seen in the context of the aging process especially of the corium and the subcutis. Morphological alterations become apparent in the form of epithelial atrophy, structural changes within the basal membrane, and a decrease in cell count of melanocytes and Langerhans cells. Signs of cellular senescence are reduced proliferation of keratinocytes, cumulation of dysplastic keratinocytes, various mutations (e.g., c-Fos/c-Jun, STAT3, FoxO1), as well as multiple lipid or amino acid metabolic aberrations (e.g., production of advanced glycation endproducts). This causes functional changes within the physical (lipid deficiency, water distribution dysfunction, lack of hygroscopic substances), chemical (pH conditions, oxygen radicals), and immunological barrier. Prophylactically, barrier-protective care products, antioxidant substances (e.g., vitamin C, B3, E, polyphenols, flavonoids), sunscreen products/measurements, and retinoids are used. For correcting alterations in aged epidermis, chemical peelings (fruit acids, β-hydroxy acid, trichloroacetic acid, phenolic compounds), non-ablative (IPL, PDL, Nd:YAG) as well as ablative (CO2, Erbium-YAG) light-assisted methods are used.
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Affiliation(s)
- J Wohlrab
- Universitätsklinik und Poliklinik für Dermatologie und Venerologie, Martin-Luther-Universität Halle-Wittenberg, Ernst-Grube-Straße 40, 06097, Halle (Saale), Deutschland. .,An-Institut für angewandte Dermatopharmazie, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Deutschland.
| | - K Hilpert
- Universitätsklinik und Poliklinik für Dermatologie und Venerologie, Martin-Luther-Universität Halle-Wittenberg, Ernst-Grube-Straße 40, 06097, Halle (Saale), Deutschland
| | - L Wolff
- Universitätsklinik und Poliklinik für Dermatologie und Venerologie, Martin-Luther-Universität Halle-Wittenberg, Ernst-Grube-Straße 40, 06097, Halle (Saale), Deutschland
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29
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Affiliation(s)
- Karl Lohner
- Institute of Molecular Biosciences, Biophysics Division, University of Graz, NAWI Graz, Austria; BioTechMed-Graz, Austria.
| | - Kai Hilpert
- Institute of Infection and Immunity, St. George's University of London, London, United Kingdom.
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30
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Czaplewski L, Bax R, Clokie M, Dawson M, Fairhead H, Fischetti VA, Foster S, Gilmore BF, Hancock REW, Harper D, Henderson IR, Hilpert K, Jones BV, Kadioglu A, Knowles D, Ólafsdóttir S, Payne D, Projan S, Shaunak S, Silverman J, Thomas CM, Trust TJ, Warn P, Rex JH. Alternatives to antibiotics-a pipeline portfolio review. Lancet Infect Dis 2016; 16:239-51. [PMID: 26795692 DOI: 10.1016/s1473-3099(15)00466-1] [Citation(s) in RCA: 524] [Impact Index Per Article: 65.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 11/06/2015] [Accepted: 11/10/2015] [Indexed: 01/21/2023]
Abstract
Antibiotics have saved countless lives and enabled the development of modern medicine over the past 70 years. However, it is clear that the success of antibiotics might only have been temporary and we now expect a long-term and perhaps never-ending challenge to find new therapies to combat antibiotic-resistant bacteria. A broader approach to address bacterial infection is needed. In this Review, we discuss alternatives to antibiotics, which we defined as non-compound approaches (products other than classic antibacterial agents) that target bacteria or any approaches that target the host. The most advanced approaches are antibodies, probiotics, and vaccines in phase 2 and phase 3 trials. This first wave of alternatives to antibiotics will probably best serve as adjunctive or preventive therapies, which suggests that conventional antibiotics are still needed. Funding of more than £1·5 billion is needed over 10 years to test and develop these alternatives to antibiotics. Investment needs to be partnered with translational expertise and targeted to support the validation of these approaches in phase 2 trials, which would be a catalyst for active engagement and investment by the pharmaceutical and biotechnology industry. Only a sustained, concerted, and coordinated international effort will provide the solutions needed for the future.
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Affiliation(s)
- Lloyd Czaplewski
- Chemical Biology Ventures, Abingdon, Oxfordshire, UK; Abgentis, Edgbaston, Birmingham, UK; Persica Pharmaceuticals, Canterbury, Kent, UK.
| | | | - Martha Clokie
- Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, UK
| | - Mike Dawson
- Novacta Biosystems, Welwyn Garden City, Hertfordshire, UK; Cantab Anti-infectives, Welwyn Garden City, Hertfordshire, UK
| | | | - Vincent A Fischetti
- Laboratory of Bacterial Pathogenesis and Immunology, The Rockefeller University, New York, NY, USA
| | - Simon Foster
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK; Absynth Biologics, Liverpool, UK
| | | | - Robert E W Hancock
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | - David Harper
- Evolution Biotechnologies, Ampthill, Bedfordshire, UK
| | - Ian R Henderson
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, Birmingham, UK
| | - Kai Hilpert
- Institute of Infection and Immunity, St George's, University of London, London, UK; TiKa Diagnostics, London, UK
| | - Brian V Jones
- School of Pharmacy and Biomolecular Sciences, University of Brighton, Brighton, UK; Queen Victoria Hospital NHS Foundation Trust, East Grinstead, West Sussex, UK
| | - Aras Kadioglu
- Institute of Infection and Global Health, University of Liverpool, Liverpool, UK
| | - David Knowles
- Absynth Biologics, Liverpool, UK; Procarta Biosystems, Norwich, UK
| | | | - David Payne
- GlaxoSmithKline, Collegeville, Pennsylvania, PA, USA
| | | | - Sunil Shaunak
- Department of Medicine, Imperial College London, London, UK
| | | | - Christopher M Thomas
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, Birmingham, UK; Plasgene, Edgbaston, Birmingham, UK
| | - Trevor J Trust
- Pan-Provincial Vaccine Enterprise, Saskatoon, SK, Canada
| | | | - John H Rex
- AstraZeneca, Boston, MA, USA; F2G, Manchester, UK
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31
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von Gundlach AR, Garamus VM, Gorniak T, Davies HA, Reischl M, Mikut R, Hilpert K, Rosenhahn A. Small angle X-ray scattering as a high-throughput method to classify antimicrobial modes of action. Biochim Biophys Acta 2015; 1858:918-25. [PMID: 26730877 DOI: 10.1016/j.bbamem.2015.12.022] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 12/17/2015] [Accepted: 12/20/2015] [Indexed: 10/22/2022]
Abstract
Multi-drug resistant bacteria are currently undermining our health care system worldwide. While novel antimicrobial drugs, such as antimicrobial peptides, are urgently needed, identification of new modes of action is money and time consuming, and in addition current approaches are not available in a high throughput manner. Here we explore how small angle X-ray scattering (SAXS) as high throughput method can contribute to classify the mode of action for novel antimicrobials and therefore supports fast decision making in drug development. Using data bases for natural occurring antimicrobial peptides or predicting novel artificial peptides, many candidates can be discovered that will kill a selected target bacterium. However, in order to narrow down the selection it is important to know if these peptides follow all the same mode of action. In addition, the mode of action should be different from conventional antibiotics, in consequence peptide candidates can be developed further into drugs against multi-drug resistant bacteria. Here we used one short antimicrobial peptide with unknown mode of action and compared the ultrastructural changes of Escherichia coli cells after treatment with the peptide to cells treated with classic antibiotics. The key finding is that SAXS as a structure sensitive tool provides a rapid feedback on drug induced ultrastructural alterations in whole E. coli cells. We could demonstrate that ultrastructural changes depend on the used antibiotics and their specific mode of action. This is demonstrated using several well characterized antimicrobial compounds and the analysis of resulting SAXS curves by principal component analysis. To understand the result of the PCA analysis, the data is correlated with TEM images. In contrast to real space imaging techniques, SAXS allows to obtain nanoscale information averaged over approximately one million cells. The measurement takes only seconds, while conventional tests to identify a mode of action require days or weeks per single substance. The antimicrobial peptide showed a different mode of action as all tested antibiotics including polymyxin B and is therefore a good candidate for further drug development. We envision SAXS to become a useful tool within the high-throughput screening pipeline of modern drug discovery. This article is part of a Special Issue entitled: Antimicrobial peptides edited by Karl Lohner and Kai Hilpert.
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Affiliation(s)
- A R von Gundlach
- Analytical Chemistry - Biointerfaces, Ruhr-University Bochum, NC4, Universitätsstr, 150, 44780 Bochum, Germany
| | - V M Garamus
- Helmholtz-Zentrum Geesthacht, Zentrum für Material- und Küstenforschung GmbH, Max-Planck-Straße 1, 21502 Geesthacht, Germany
| | - T Gorniak
- Analytical Chemistry - Biointerfaces, Ruhr-University Bochum, NC4, Universitätsstr, 150, 44780 Bochum, Germany
| | - H A Davies
- Life Health and Chemical Sciences, Open University, Walton Hall, Milton Keynes MK7 6AA, United Kingdom
| | - M Reischl
- Institute for Applied Computer Science (IAI), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - R Mikut
- Institute for Applied Computer Science (IAI), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - K Hilpert
- Institute of Infection and Immunology, St. George's University of London (SGUL), Cranmer Terrace, London SW17 0RE, United Kingdom
| | - A Rosenhahn
- Analytical Chemistry - Biointerfaces, Ruhr-University Bochum, NC4, Universitätsstr, 150, 44780 Bochum, Germany
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32
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Mikut R, Ruden S, Reischl M, Breitling F, Volkmer R, Hilpert K. Improving short antimicrobial peptides despite elusive rules for activity. Biochim Biophys Acta 2015; 1858:1024-33. [PMID: 26687790 DOI: 10.1016/j.bbamem.2015.12.013] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 11/25/2015] [Accepted: 12/09/2015] [Indexed: 10/22/2022]
Abstract
Antimicrobial peptides (AMPs) can effectively kill a broad range of life threatening multidrug-resistant bacteria, a serious threat to public health worldwide. However, despite great hopes novel drugs based on AMPs are still rare. To accelerate drug development we studied different approaches to improve the antibacterial activity of short antimicrobial peptides. Short antimicrobial peptides seem to be ideal drug candidates since they can be synthesized quickly and easily, modified and optimized. In addition, manufacturing a short peptide drug will be more cost efficient than long and structured ones. In contrast to longer and structured peptides short AMPs seem hard to design and predict. Here, we designed, synthesized and screened five different peptide libraries, each consisting of 600 9-mer peptides, against Pseudomonas aeruginosa. Each library is presenting a different approach to investigate effectiveness of an optimization strategy. The data for the 3000 peptides were analyzed using models based on fuzzy logic bioinformatics and plausible descriptors. The rate of active or superior active peptides was improved from 31.0% in a semi-random library from a previous study to 97.8% in the best new designed library. This article is part of a Special Issue entitled: Antimicrobial peptides edited by Karl Lohner and Kai Hilpert.
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Affiliation(s)
- Ralf Mikut
- Karlsruhe Institute of Technology (KIT), Institute for Applied Computer Science, P.O. Box 3640, 76021 Karlsruhe, Germany
| | - Serge Ruden
- Karlsruhe Institute of Technology (KIT), Institute of Functional Interfaces and Institute of Biological Interfaces 2, P.O. Box 3640, 76021 Karlsruhe, Germany
| | - Markus Reischl
- Karlsruhe Institute of Technology (KIT), Institute for Applied Computer Science, P.O. Box 3640, 76021 Karlsruhe, Germany
| | - Frank Breitling
- Karlsruhe Institute of Technology (KIT), Institute of Microstructure Technology, P.O. Box 3640, 76021 Karlsruhe, Germany
| | - Rudolf Volkmer
- Institute of Medical Immunology, Universitätsklinikum Charité, Humboldt-Universität zu Berlin, Schumannstr. 20-21, 10117 Berlin, Germany
| | - Kai Hilpert
- Karlsruhe Institute of Technology (KIT), Institute of Functional Interfaces and Institute of Biological Interfaces 2, P.O. Box 3640, 76021 Karlsruhe, Germany; Karlsruhe Institute of Technology (KIT), Institute of Microstructure Technology, P.O. Box 3640, 76021 Karlsruhe, Germany; Institute of Infection and Immunity, St. George's University of London, Cranmer Terrace, London, SW17 0RE, United Kingdom.
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Yu K, Lai BFL, Gani J, Mikut R, Hilpert K, Kizhakkedathu JN. Interaction of blood components with cathelicidins and their modified versions. Biomaterials 2015; 69:201-11. [PMID: 26295533 DOI: 10.1016/j.biomaterials.2015.08.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2015] [Revised: 07/30/2015] [Accepted: 08/02/2015] [Indexed: 12/21/2022]
Abstract
Cationic antimicrobial peptides (cAMPs) serve as effective components of the innate host defense against microbial infections. cAMPs often show broad-spectrum antimicrobial activity, but narrow-band activity is also observed. Despite their great potential, the polycationic nature of cAMPs could cause serious side effects once in the bloodstream which may limit their applications. However, there is very limited knowledge available on AMPs interaction with blood components in spite of the fact that the most likely route of administration to treat systemic microbial infections for these peptides is intravenous, where they immediately come in contact with all blood components. In order to evaluate the therapeutic potential of cAMPs as new alternative to antibiotics, we investigated the impact of cathelicidin related cAMPs on red blood cell lysis, aggregation, platelet activation, blood coagulation, and complement activation. The influence of cAMPs on blood depends on hydrophobicity and number of charges in the peptides. The hemolytic activity of cathelicidin (bactenecin) variants was much less than that of indolicidin due to their lower hydrophobicity. Except indolicidin, none of the peptides induce platelet activation. Some of bactenecin variants (R3, Sub3 and W3) with higher charge inhibited the blood coagulation. The cAMPs did not activate or inhibit complement at the concentrations studied, expect for the peptide (Sub3). Our data shows that it is important to investigate cAMP-based drug candidates regarding their interaction with blood components early on in the development process. We anticipate that this new knowledge on blood interaction of antimicrobial peptides will help to design peptides with a better therapeutic window and with less side effects.
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Affiliation(s)
- Kai Yu
- Centre for Blood Research and Department of Pathology & Laboratory Medicine, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Benjamin F L Lai
- Centre for Blood Research and Department of Pathology & Laboratory Medicine, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Jurnorain Gani
- Institute of Infection and Immunity, St George's University of London, Cranmer Terrace, London SW17 0RE, UK
| | - Ralf Mikut
- Karlsruhe Institute of Technology, Institute for Applied Computer Science, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Kai Hilpert
- Institute of Infection and Immunity, St George's University of London, Cranmer Terrace, London SW17 0RE, UK.
| | - Jayachandran N Kizhakkedathu
- Centre for Blood Research and Department of Pathology & Laboratory Medicine, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada; Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada.
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Abstract
The change in the population's age structure in most industrial countries, as in Germany, requires geriatric medicine to play an increasingly important role. Dermatology also has to meet the new challenges by expert discussion and ethical considerations. The physiological aging process is influenced by intrinsic and extrinsic factors and causes a variety of morphological and functional alterations in the skin. Those alterations are the cause for an increasing prevalence of many dermatoses. Infections, wound healing disorders, inflammatory diseases, tumors and associated paraneoplastic syndromes are of particular importance. The structural and functional characteristics of aging skin in combination with the reduced mobility and declining cognitive abilities in elder patients require specific recommendations for skin protection as well as qualified advice about topical and systemic use of medications.
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Affiliation(s)
- J Wohlrab
- Universitätsklinik und Poliklinik für Dermatologie und Venerologie, Martin-Luther-Universität Halle-Wittenberg, Ernst-Grube-Straße 40, 06097, Halle (Saale), Deutschland,
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Abstract
The Al-Ni phase diagram has been investigated in the com position range xNi = 0.70 to 0.97. Phase boundaries were determined by using differential thermal analysis and Knudsen effusion mass spectrometry. The measurements were carried out in the temperature range between 1409 and 1730K. An Al-Ni phase diagram is obtained for xNi ≧ 0.70 by combining the data from this work with selected data from the literature. This diagram deviates from that recommended by phase diagram compilations and used generally in the literature to date; it agrees reasonably well with a diagram which has been rejected in the literature.
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Affiliation(s)
- K. Hilpert
- Institute for Reactor Materials, Nuclear Research Centre (KFA) Jülich, Federal Republic of Germany
| | - D. Kobertz
- Institute for Reactor Materials, Nuclear Research Centre (KFA) Jülich, Federal Republic of Germany
| | - V. Venugopal
- Fuel Chemistry Division, Bhabha Atomic Research Centre, Bombay 400085, India
| | - M. Miller
- Technical University of Wrocław, Wybrzeże S. Wyspiańskiego 27, 50-370 Wrocław, Poland
| | - H. Gerads
- Institute for Reactor Materials, Nuclear Research Centre (KFA) Jülich, Federal Republic of Germany
| | - F. J. Bremer
- Institute for Solid State Physics, Nuclear Research Centre (KFA) Jülich
| | - H. Nickel
- Institute for Solid State Physics, Nuclear Research Centre (KFA) Jülich
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Odoj R, Hilpert K. Mass Spectrometric Investigations of the Evaporation of Crystalline Compounds of the System Cs2O-Al2O3-SiO2 Part II: The Compounds CsAlSiO4 and CsAlSi5O12. ACTA ACUST UNITED AC 2014. [DOI: 10.1515/zna-1980-0103] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract The evaporation of the synthetic compounds CsAlSiO4 and CsAlSi5O12 was studied by high temperature mass spectrometry. The measurements were carried out under equilibrium conditions with Knudsen cells in the temperature ranges 1242 to 1567 K (CsAlSiO4) and 1542 to 1803 K (CsAlSi5O12). The obtained Cs partial pressures are given by the equations
log p (Pa)=-18497/T(K)+11.85(CsAlSiO4)and
log p (Pa)=-26 974/T(K)+14.6(CsAlSi5012).
The probable uncertainty of the vapor pressures is ± 43%. The following enthalpies of sublimation of Cs (g) were computed:
⊿Sub H°1405 (CsAlSiO4) =353.6 ± 9.8 kJ mol-1 and
⊿Sub H°1673 (CsAlSi5O12) =516.3 ± 18 kJ mol-1.
The Cs partial pressures over CsAlSiO4, CsAlSi5O12 and CsAlSi2O6 (see part I of this work [1]) are discussed with respect to their consequences for the final storage of high level radioactive waste.
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Affiliation(s)
- R. Odoj
- Institut für Chemie der Kernforschungsanlage Jülich, Institut 4: Angewandte Physikalische Chemie
| | - K. Hilpert
- Institut für Chemie der Kernforschungsanlage Jülich, Institut 4: Angewandte Physikalische Chemie
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Hilpert K, Gerads H, Kobertz D, Miller M. Composition and thermochemistry of the equilibrium vapour of the systems NaI-FeI2and NaI-PbI2. ACTA ACUST UNITED AC 2014. [DOI: 10.1002/bbpc.19870910308] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Cornejo A, Oliveira CRD, Wurtele M, Chung J, Hilpert K, Schenkman S. A novel monoclonal antibody against the C-terminus of β-tubulin recognizes endocytic organelles in Trypanosoma cruzi. Protein Pept Lett 2012; 19:636-43. [PMID: 22519535 DOI: 10.2174/092986612800494075] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Revised: 09/03/2011] [Accepted: 11/16/2011] [Indexed: 11/22/2022]
Abstract
Microtubule cytoskeleton is a dynamic structure involved in the maintenance of eukaryote cell shape, motion of cilia and flagellum, and intracellular movement of vesicles and organelles. Many antibodies against tubulins have been described, most of them against the C-terminal portion, which is exposed at the outside of the microtubules. By generating a novel set of monoclonal antibodies against the cytoskeleton of Trypanosoma cruzi, a flagellate protozoan that causes Chagas' disease, we selected a clone (mAb 3G4) that recognizes β-tubulin. The epitope for mAb 3G4 was mapped by pepscan to a highly conserved sequence motif found between α-helices 11 and 12 of the C-terminus of β-tubulin in eukaryotes. It labels vesicular structures in both T. cruzi and mammalian cells, colocalizing respectively with a major cysteine protease (Cruzipain) and lysosome associated protein (LAMP2) respectively, but it does not label regular microtubules on these cellular models. We propose that the epitope recognized by mAb 3G4 is exposed only in a form of tubulin associated with endosomes.
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Affiliation(s)
- Alberto Cornejo
- Center of Study of Social Insects, Department of Biology, Institute of Biosciences of Rio Claro, São Paulo State University, UNESP--Univ. Estadual Paulista, Rio Claro, SP, Brazil
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Gao G, Lange D, Hilpert K, Kindrachuk J, Zou Y, Cheng JT, Kazemzadeh-Narbat M, Yu K, Wang R, Straus SK, Brooks DE, Chew BH, Hancock RE, Kizhakkedathu JN. The biocompatibility and biofilm resistance of implant coatings based on hydrophilic polymer brushes conjugated with antimicrobial peptides. Biomaterials 2011; 32:3899-909. [DOI: 10.1016/j.biomaterials.2011.02.013] [Citation(s) in RCA: 254] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Accepted: 02/09/2011] [Indexed: 01/18/2023]
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Hilpert K. Identifying Novel Antimicrobial Peptides with Therapeutic Potential Against Multidrug-Resistant Bacteria by Using the SPOT Synthesis. MINI-REV ORG CHEM 2011. [DOI: 10.2174/157019311795177781] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Wieczorek M, Jenssen H, Kindrachuk J, Scott WRP, Elliott M, Hilpert K, Cheng JTJ, Hancock REW, Straus SK. Structural studies of a peptide with immune modulating and direct antimicrobial activity. ACTA ACUST UNITED AC 2011; 17:970-80. [PMID: 20851346 DOI: 10.1016/j.chembiol.2010.07.007] [Citation(s) in RCA: 122] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2010] [Revised: 07/03/2010] [Accepted: 07/07/2010] [Indexed: 01/17/2023]
Abstract
The structure and function of the synthetic innate defense regulator peptide 1018 was investigated. This 12 residue synthetic peptide derived by substantial modification of the bovine cathelicidin bactenecin has enhanced innate immune regulatory and moderate direct antibacterial activities. The solution state NMR structure of 1018 in zwitterionic dodecyl phosphocholine (DPC) micelles indicated an α-helical conformation, while secondary structures, based on circular dichroism measurements, in anionic sodium dodecyl sulfate (SDS) and phospholipid vesicles (POPC/PG in a 1:1 molar ratio) and simulations revealed that 1018 can adopt a variety of folds, tailored to its different functions. The structural data are discussed in light of the ability of 1018 to potently induce chemokine responses, suppress the LPS-induced TNF-α response, and directly kill both Gram-positive and Gram-negative bacteria.
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Affiliation(s)
- Michal Wieczorek
- Chemistry Department, University of British Columbia, Vancouver, BC, Canada
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Abstract
Peptide arrays are a widely used tool in proteomic research for investigations of drug development and molecular interactions including protein-protein or protein-peptide interactions. Most peptide synthesis techniques are able to simultaneously synthesize only up to a few hundred single peptides. Using the SPOT™ technique, it is possible to synthesize and screen in parallel up to 8,000 peptides or peptide mixtures. In addition, such peptides can be released from the membrane and transferred onto peptide microarrays. Here we present protocols for the peptides synthesis on cellulose including the preparation of different cellulose membranes and easy-to-use detection methods on these peptide macroarrays. In addition, a protocol to produce and screen peptide microarray using the SPOT technology is provided.
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Affiliation(s)
- Dirk F H Winkler
- Peptide Facility, Kinexus Bioinformatics Corporation, Vancouver, BC, Canada
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Hilpert K. Study of the Vaporization of Amalgams with a New Knudsen Cell - Mass Spectrometer System. Part II: The Compounds Mg5Hg3, Mg2Hg, Mg5Hg2, and Mg3Hg and the Formation Enthalpies of All Compounds of the Mg - Hg System. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bbpc.19840880110] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Hilpert K, Bencivenni L, Saha B. Molecular Composition and Thermochemistry of Tin(II), Lead(II), and Scandium(III) Iodide Vapours. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bbpc.19850891210] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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