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Kraut-Cohen J, Frenkel O, Covo S, Marcos-Hadad E, Carmeli S, Belausov E, Minz D, Cytryn E. A pipeline for rapidly evaluating activity and inferring mechanisms of action of prospective antifungal compounds. PEST MANAGEMENT SCIENCE 2024; 80:2804-2816. [PMID: 38323791 DOI: 10.1002/ps.7989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 01/22/2024] [Accepted: 01/23/2024] [Indexed: 02/08/2024]
Abstract
BACKGROUND Fungal phytopathogens are a significant threat to crops and food security, and there is a constant need to develop safe and effective compounds that antagonize them. In-planta assays are complex and tedious and are thus not suitable for initial high-throughput screening of new candidate antifungal compounds. We propose an in vitro screening pipeline that integrates five rapid quantitative and qualitative methods to estimate the efficacy and mode of action of prospective antifungal compounds. RESULTS The pipeline was evaluated using five documented antifungal compounds (benomyl, catechol, cycloheximide, 2,4-diacetylphloroglucinol, and phenylacetic acid) that have different modes of action and efficacy, against the model soilborne fungal pathogen Fusarium oxysporum f. sp. radicis cucumerinum. We initially evaluated the five compounds' ability to inhibit fungal growth and metabolic activity using green fluorescent protein (GFP)-labeled F. oxysporum and PrestoBlue staining, respectively, in multiwell plate assays. We tested the compounds' inhibition of both conidial germination and hyphal elongation. We then employed FUN-1 and SYTO9/propidium iodide staining, coupled to confocal microscopy, to differentiate between fungal growth inhibition and death at the cellular level. Finally, using a reactive oxygen species (ROS)-detection assay, we were able to quantify ROS production in response to compound application. CONCLUSIONS Collectively, the proposed pipeline provides a wide array of quantitative and qualitative data on the tested compounds that can help pinpoint promising novel compounds; these can then be evaluated more vigorously using in planta screening assays. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Judith Kraut-Cohen
- Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
| | - Omer Frenkel
- Department of Plant Pathology and Weed Research, Institute of Plant Protection, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
| | - Shay Covo
- Department of Plant Pathology and Microbiology, Robert H. Smith Faculty of Agriculture, Food and Environment, Hebrew University, Rehovot, Israel
| | - Evgeniya Marcos-Hadad
- Department of Plant Pathology and Microbiology, Robert H. Smith Faculty of Agriculture, Food and Environment, Hebrew University, Rehovot, Israel
| | - Shmuel Carmeli
- Raymond and Beverly Sackler School of Chemistry, Faculty of Exact Sciences, Tel Aviv University, Ramat Aviv, Israel
| | - Eduard Belausov
- Confocal Microscopy Unit, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
| | - Dror Minz
- Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
| | - Eddie Cytryn
- Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
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2
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Herman TS, da Silva Goersch C, Bocca AL, Fernandes L. Resazurin to determine the minimum inhibitory concentration on antifungal susceptibility assays for Fonsecaea sp. using a modified EUCAST protocol. Braz J Microbiol 2024; 55:1349-1357. [PMID: 38438831 PMCID: PMC11153478 DOI: 10.1007/s42770-024-01293-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 02/27/2024] [Indexed: 03/06/2024] Open
Abstract
Chromoblastomycosis is a fungal chronic disease, which affects humans, especially in cutaneous and subcutaneous tissues. There is no standard treatment for Chromoblastomycosis, and it is a therapeutic challenge, due natural resistance of their causative agents, inadequate response of patients and common cases of relapse. Protocols for determination of antifungal drugs susceptibility are not standardized for chromoblastomycosis agents and endpoint definition is usually based on visual inspection, which depends on the analyst, making it sometimes inaccurate. We presented a colorimetric and quantitative methodology based on resazurin reduction to resofurin to determine the metabolic status of viable cells of Fonsecaea sp. Performing antifungal susceptibility assay by a modified EUCAST protocol allied to resazurin, we validated the method to identify the minimum inhibitory concentrations of itraconazole, fluconazole, amphotericin B, and terbinafine for eight Fonsecaea clinical isolates. According to our data, resazurin is a good indicator of metabolic status of viable cells, including those exposed to antifungal drugs. This work aimed to test resazurin as an indicator of the metabolic activity of Fonsecaea species in susceptibility assays to antifungal drugs. Species of this genus are the main causative agents of Chromoblastomycosis, which affects humans.
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Affiliation(s)
- Tatiana Sobianski Herman
- Postgraduate Program in Molecular Pathology, Faculty of Medicine, University of Brasília, UnB, Brasília, DF, Brazil
- Laboratory of Applied Immunology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, UnB, Room J1 28/8, Brasília, DF, 70910-900, Brazil
| | - Camila da Silva Goersch
- Laboratory of Applied Immunology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, UnB, Room J1 28/8, Brasília, DF, 70910-900, Brazil
- Postgraduate Program in Microbial Biology, Institute of Biological Science, University of Brasília, UnB, Brasília, DF, Brazil
| | - Anamelia Lorenzetti Bocca
- Postgraduate Program in Molecular Pathology, Faculty of Medicine, University of Brasília, UnB, Brasília, DF, Brazil
- Laboratory of Applied Immunology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, UnB, Room J1 28/8, Brasília, DF, 70910-900, Brazil
| | - Larissa Fernandes
- Laboratory of Applied Immunology, Department of Cell Biology, Institute of Biological Sciences, University of Brasília, UnB, Room J1 28/8, Brasília, DF, 70910-900, Brazil.
- Postgraduate Program in Microbial Biology, Institute of Biological Science, University of Brasília, UnB, Brasília, DF, Brazil.
- Faculty of Ceilândia, University of Brasília, UnB, Brasília, DF, Brazil.
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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] [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] [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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Samlali K, Alves CL, Jezernik M, Shih SCC. Droplet digital microfluidic system for screening filamentous fungi based on enzymatic activity. MICROSYSTEMS & NANOENGINEERING 2022; 8:123. [PMID: 36438986 PMCID: PMC9681769 DOI: 10.1038/s41378-022-00456-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 07/24/2022] [Accepted: 09/13/2022] [Indexed: 06/16/2023]
Abstract
Fungal cell-wall-degrading enzymes have great utility in the agricultural and food industries. These cell-wall-degrading enzymes are known to have functions that can help defend against pathogenic organisms. The existing methods used to discover these enzymes are not well adapted to fungi culture and morphology, which prevents the proper evaluation of these enzymes. We report the first droplet-based microfluidic method capable of long-term incubation and low-voltage conditions to sort filamentous fungi inside nanoliter-sized droplets. The new method was characterized and validated in solid-phase media based on colloidal chitin such that the incubation of single spores in droplets was possible over multiple days (2-4 days) and could be sorted without droplet breakage. With long-term culture, we examined the activity of cell-wall-degrading enzymes produced by fungi during solid-state droplet fermentation using three highly sensitive fluorescein-based substrates. We also used the low-voltage droplet sorter to select clones with highly active cell-wall-degrading enzymes, such as chitinases, β-glucanases, and β-N-acetylgalactosaminidases, from a filamentous fungi droplet library that had been incubated for >4 days. The new system is portable, affordable for any laboratory, and user-friendly compared to classical droplet-based microfluidic systems. We propose that this system will be useful for the growing number of scientists interested in fungal microbiology who are seeking high-throughput methods to incubate and sort a large library of fungal cells.
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Affiliation(s)
- Kenza Samlali
- Department of Electrical and Computer Engineering, Concordia University, Montréal, QC Canada
- Centre for Applied Synthetic Biology, Concordia University, Montréal, QC Canada
| | - Chiara Leal Alves
- Department of Electrical and Computer Engineering, Concordia University, Montréal, QC Canada
- Centre for Applied Synthetic Biology, Concordia University, Montréal, QC Canada
| | - Mara Jezernik
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON Canada
| | - Steve C. C. Shih
- Department of Electrical and Computer Engineering, Concordia University, Montréal, QC Canada
- Centre for Applied Synthetic Biology, Concordia University, Montréal, QC Canada
- Department of Biology, Concordia University, Montréal, QC Canada
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Greve JM, Cowan JA. Activity and Synergy of Cu-ATCUN Antimicrobial Peptides. Int J Mol Sci 2022; 23:ijms232214151. [PMID: 36430622 PMCID: PMC9692552 DOI: 10.3390/ijms232214151] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/08/2022] [Accepted: 11/11/2022] [Indexed: 11/19/2022] Open
Abstract
Antibiotic resistance demands innovative strategies and therapies. The pairs of antimicrobial peptides tested in this work show broad-spectrum synergy and are capable of interacting with diverse bacterial membranes. In most cases, the ATCUN motif enhanced the activity of peptides tested in combination. Our studies also show CP10A to be a multifaceted peptide, displaying both cell membrane and intracellular activity and acting as a chameleon, improving the activity of other peptides as needed. The results of the synergy experiments demonstrate the importance of varied modes of action and how these changes can affect the ability to combat pathogens, while also illustrating the value of the metal-binding domain in enhancing the activity of antimicrobial peptides in combination.
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7
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Zhang W, Lv Y, Yang H, Wei S, Zhang S, Li N, Hu Y. Sub3 Inhibits Mycelia Growth and Aflatoxin Production of Aspergillus Flavus. FOOD BIOPHYS 2022. [DOI: 10.1007/s11483-021-09715-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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8
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Li H, Tamang T, Nantasenamat C. Toward insights on antimicrobial selectivity of host defense peptides via machine learning model interpretation. Genomics 2021; 113:3851-3863. [PMID: 34480984 DOI: 10.1016/j.ygeno.2021.08.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 08/22/2021] [Accepted: 08/25/2021] [Indexed: 10/20/2022]
Abstract
Host defense peptides are promising candidates for the development of novel antibiotics. To realize their therapeutic potential, high levels of target selectivity is essential. This study aims to identify factors governing selectivity via the use of the random forest algorithm for correlating peptide sequence information with their bioactivity data. Satisfactory predictive models were achieved from out-of-bag prediction that yielded accuracies and Matthew's correlation coefficients in excess of 0.80 and 0.57, respectively. Model interpretation through the use of variable importance metrics and partial dependence plots indicated that the selectivity was heavily influenced by the composition and distribution patterns of molecular charge and solubility related parameters. Furthermore, the three investigated bacterial target species (Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus) likely had a significant influence on how selectivity was realized as there appears to be a similar underlying selectivity mechanism on the basis of charge-solubility properties (i.e. but which is tailored according to the target in question).
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Affiliation(s)
- Hao Li
- Center of Data Mining and Biomedical Informatics, Faculty of Medical Technology, Mahidol University, Bangkok 10700, Thailand
| | - Thinam Tamang
- Madan Bhandari Memorial College, Institute of Science and Technology, Tribhuvan University, Kathmandu 44602, Nepal
| | - Chanin Nantasenamat
- Center of Data Mining and Biomedical Informatics, Faculty of Medical Technology, Mahidol University, Bangkok 10700, Thailand.
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Riciluca KCT, Oliveira UC, Mendonça RZ, Bozelli Junior JC, Schreier S, da Silva Junior PI. Rondonin: antimicrobial properties and mechanism of action. FEBS Open Bio 2021; 11:2541-2559. [PMID: 34254458 PMCID: PMC8409319 DOI: 10.1002/2211-5463.13253] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 06/13/2021] [Accepted: 07/12/2021] [Indexed: 02/01/2023] Open
Abstract
Infectious diseases are among the major causes of death in the human population. A wide variety of organisms produce antimicrobial peptides (AMPs) as part of their first line of defense. A peptide from Acanthoscurria rondoniae plasma, rondonin—with antifungal activity, a molecular mass of 1236 Da and primary sequence IIIQYEGHKH—was previously studied (UniProt accession number B3EWP8). It showed identity with the C terminus of subunit ‘D’ of the hemocyanin of the Aphonopelma hentzi spider. This result led us to propose a new pathway of the immune system of arachnids that suggests a new function to hemocyanin: production of antimicrobial peptides. Rondonin does not interact with model membranes and was able to bind to yeast nucleic acids but not bacteria. It was not cytotoxic against mammalian cells. The antifungal activity of rondonin is pH‐dependent and peaks at pH ˜ 4–5. The peptide presents synergism with gomesin (spider hemocyte antimicrobial peptide—UniProtKB—P82358) against human yeast pathogens, suggesting a new potential alternative treatment option. Antiviral activity was detected against RNA viruses, measles, H1N1, and encephalomyocarditis. This is the first report of an arthropod hemocyanin fragment with activity against human viruses. Currently, it is vital to invest in the search for natural and synthetic antimicrobial compounds that, above all, present alternative mechanisms of action to first‐choice antimicrobials.
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Affiliation(s)
- Katie C T Riciluca
- Center of Toxins, Immune-Response and Cell Signaling - CeTICS/CEPID, Laboratory for Applied Toxinology, Butantan Institute, São Paulo, Brazil.,Post-Graduation Program Interunits in Biotechnology, USP/IPT/IBU, São Paulo, Brazil
| | - Ursula C Oliveira
- Center of Toxins, Immune-Response and Cell Signaling - CeTICS/CEPID, Laboratory for Applied Toxinology, Butantan Institute, São Paulo, Brazil
| | | | - José C Bozelli Junior
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, Brazil.,Department of Biochemistry and Biomedical Sciences, Health Sciences Centre, McMaster University, Hamilton, ON, Canada
| | - Shirley Schreier
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, Brazil
| | - Pedro I da Silva Junior
- Center of Toxins, Immune-Response and Cell Signaling - CeTICS/CEPID, Laboratory for Applied Toxinology, Butantan Institute, São Paulo, Brazil.,Post-Graduation Program Interunits in Biotechnology, USP/IPT/IBU, São Paulo, Brazil
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10
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Zhang W, Lv Y, Lv A, Wei S, Zhang S, Li C, Hu Y. Sub3 inhibits Aspergillus flavus growth by disrupting mitochondrial energy metabolism, and has potential biocontrol during peanut storage. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2021; 101:486-496. [PMID: 32643802 DOI: 10.1002/jsfa.10657] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 06/16/2020] [Accepted: 07/09/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Aspergillus flavus, a saprophytic fungus, is regularly detected in oil-enriched seeds. During colonization, this organism releases aflatoxins that pose a serious risk to food safety and human health. Therefore, an eco-friendly biological approach to inhibit the pathogen is desirable. RESULTS Experimental results indicated that A. flavus spores could not germinate in potato dextrose broth culture medium, when the concentration of Sub3 exceeded 0.15 g L-1 . Morphological evaluation performed by flow cytometry and scanning electron microscopy indicated that spores were shrunken and pitted following Sub3 exposure. Physiological assessment using propidium iodide, 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolocarbocyanine iodide, 2,7-dichlorodihydrofluorescein diacetate and 4',6-diamidino-2-phenylindole staining revealed damaged cell membranes, decreased mitochondrial membrane potential, increased intracellular reactive oxygen species levels, and elevated large nuclear condensation and DNA fragmentation. Moreover, mitochondrial dehydrogenase activity was reduced by 29.42% and 45.48% after treatment with 0.1 and 0.15 g L-1 Sub3, respectively. Additionally, colonization capacity in peanut was significantly decreased, and the number of spores on seeds treated with Sub3 was decreased by 26.86% (0.1 g L-1 ) and 77.74% (0.15 g L-1 ) compared with the control group. CONCLUSION Sub3 likely inhibits A. flavus by crossing the cell wall and targeting the cell membrane, disrupting mitochondrial energy metabolism, and inducing DNA damage, leading to spore death. Thus, Sub3 may provide a useful biocontrol strategy to control A. flavus growth in peanuts. © 2020 Society of Chemical Industry.
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Affiliation(s)
- Wei Zhang
- College of Biological Engineering, Henan University of Technology, Zhengzhou, P. R. China
| | - Yangyong Lv
- College of Biological Engineering, Henan University of Technology, Zhengzhou, P. R. China
| | - Ang Lv
- College of Biological Engineering, Henan University of Technology, Zhengzhou, P. R. China
| | - Shan Wei
- College of Biological Engineering, Henan University of Technology, Zhengzhou, P. R. China
| | - Shuaibing Zhang
- College of Biological Engineering, Henan University of Technology, Zhengzhou, P. R. China
| | - Cuixiang Li
- College of Biological Engineering, Henan University of Technology, Zhengzhou, P. R. China
| | - Yuansen Hu
- College of Biological Engineering, Henan University of Technology, Zhengzhou, P. R. China
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11
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Systematic Identification of Protein Targets of Sub5 Using Saccharomyces cerevisiae Proteome Microarrays. Int J Mol Sci 2021; 22:ijms22020760. [PMID: 33451135 PMCID: PMC7828587 DOI: 10.3390/ijms22020760] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 12/08/2020] [Accepted: 12/09/2020] [Indexed: 11/17/2022] Open
Abstract
Antimicrobial peptides (AMPs) are intensively studied in terms of alternative drugs. Sub5 is a synthetic 12-mer AMP with substitutions of five amino acids of bactenecin 2A (Bac2A), a linear-ized bactenecin variant of bovine. Sub5 is highly effective against fungi with an ability to trans-locate cell membrane, but its targets are unknown. Systematic analysis of Sub5 targets will facil-itate our understanding on its mechanism of action. In this study, we used high-throughput Saccharomyces cerevisiae proteome microarrays to explore the potential protein targets of Sub5. The screening results showed 128 potential protein targets of Sub5. Bioinformatics analysis of protein targets of Sub5 revealed significant gene ontology (GO) enrichment in actin related pro-cess of “actin filament-based process”, “actin filament organization”, “actin cortical patch or-ganization”, regulation of “actin filament bundle assembly”. Moreover, the other enriched cat-egories in GO enrichment mostly contained actin associate proteins. In total, 11 actin-associated proteins were identified in the protein targets of Sub5. Protein family (PFAM) enrichment anal-ysis shows protein domain enriched in actin binding, i.e., “Cytoskeletal-regulatory complex EF hand (helix E-loop-helix F motif)”. Being consistent with GO analysis, Search Tool for the Re-trieval of Interacting Genes/Proteins (STRING) analysis of the protein targets of Sub5 showed ac-tin network with involvement of 15 protein targets. Along with actin-network, STRING analysis showed protein–protein interaction network in ribonucleoprotein, transcription and translation, chromosome, histone, and ubiquitin related, DNA repair, and chaperone. Multiple Expression motifs for Motif Elicitation (MEME) suite provided a consensus binding motif of [ED][ED]EEE[ED][ED][ED][ED][ED], in total of 75 protein targets of Sub5. This motif was present in 9 out of 15 actin-related proteins identified among protein targets of Sub5.
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12
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Maiti BK, Govil N, Kundu T, Moura JJG. Designed Metal-ATCUN Derivatives: Redox- and Non-redox-Based Applications Relevant for Chemistry, Biology, and Medicine. iScience 2020; 23:101792. [PMID: 33294799 PMCID: PMC7701195 DOI: 10.1016/j.isci.2020.101792] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
The designed “ATCUN” motif (amino-terminal copper and nickel binding site) is a replica of naturally occurring ATCUN site found in many proteins/peptides, and an attractive platform for multiple applications, which include nucleases, proteases, spectroscopic probes, imaging, and small molecule activation. ATCUN motifs are engineered at periphery by conjugation to recombinant proteins, peptides, fluorophores, or recognition domains through chemically or genetically, fulfilling the needs of various biological relevance and a wide range of practical usages. This chemistry has witnessed significant growth over the last few decades and several interesting ATCUN derivatives have been described. The redox role of the ATCUN moieties is also an important aspect to be considered. The redox potential of designed M-ATCUN derivatives is modulated by judicious choice of amino acid (including stereochemistry, charge, and position) that ultimately leads to the catalytic efficiency. In this context, a wide range of M-ATCUN derivatives have been designed purposefully for various redox- and non-redox-based applications, including spectroscopic probes, target-based catalytic metallodrugs, inhibition of amyloid-β toxicity, and telomere shortening, enzyme inactivation, biomolecules stitching or modification, next-generation antibiotic, and small molecule activation.
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Affiliation(s)
- Biplab K Maiti
- National Institute of Technology Sikkim, Ravangla Campus, Barfung Block, Ravangla Sub Division, South Sikkim 737139, India
| | - Nidhi Govil
- National Institute of Technology Sikkim, Ravangla Campus, Barfung Block, Ravangla Sub Division, South Sikkim 737139, India
| | - Taraknath Kundu
- National Institute of Technology Sikkim, Ravangla Campus, Barfung Block, Ravangla Sub Division, South Sikkim 737139, India
| | - José J G Moura
- LAQV-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal
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13
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Basso V, Tran DQ, Ouellette AJ, Selsted ME. Host Defense Peptides as Templates for Antifungal Drug Development. J Fungi (Basel) 2020; 6:jof6040241. [PMID: 33113935 PMCID: PMC7711597 DOI: 10.3390/jof6040241] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 10/20/2020] [Accepted: 10/21/2020] [Indexed: 12/15/2022] Open
Abstract
Current treatment for invasive fungal diseases is limited to three classes of antifungal drugs: azoles, polyenes, and echinocandins. The most recently introduced antifungal class, the echinocandins, was first approved nearly 30 years ago. The limited antifungal drug portfolio is rapidly losing its clinical utility due to the inexorable rise in the incidence of invasive fungal infections and the emergence of multidrug resistant (MDR) fungal pathogens. New antifungal therapeutic agents and novel approaches are desperately needed. Here, we detail attempts to exploit the antifungal and immunoregulatory properties of host defense peptides (HDPs) in the design and evaluation of new antifungal therapeutics and discuss historical limitations and recent advances in this quest.
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Affiliation(s)
- Virginia Basso
- Department of Pathology and Laboratory Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA; (V.B.); (D.Q.T.); (A.J.O.)
| | - Dat Q. Tran
- Department of Pathology and Laboratory Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA; (V.B.); (D.Q.T.); (A.J.O.)
- Oryn Therapeutics, Vacaville, CA 95688, USA
| | - André J. Ouellette
- Department of Pathology and Laboratory Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA; (V.B.); (D.Q.T.); (A.J.O.)
- Norris Comprehensive Cancer Center of the University of Southern California, Los Angeles, CA 90089, USA
| | - Michael E. Selsted
- Department of Pathology and Laboratory Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA; (V.B.); (D.Q.T.); (A.J.O.)
- Oryn Therapeutics, Vacaville, CA 95688, USA
- Norris Comprehensive Cancer Center of the University of Southern California, Los Angeles, CA 90089, USA
- Correspondence:
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14
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Tamminen A, Happonen P, Barth D, Holmström S, Wiebe MG. High throughput, small scale methods to characterise the growth of marine fungi. PLoS One 2020; 15:e0236822. [PMID: 32764772 PMCID: PMC7413501 DOI: 10.1371/journal.pone.0236822] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 07/14/2020] [Indexed: 11/26/2022] Open
Abstract
Various marine fungi have been shown to produce interesting, bioactive compounds, but scaling up the production of these compounds can be challenging, particularly because little is generally known about how the producing organisms grow. Here we assessed the suitability of using 100-well BioScreen plates or 96-well plates incubated in a robot hotel to cultivate eight filamentous marine fungi, six sporulating and two non-sporulating, to obtain data on growth and substrate (glucose, xylose, galactose or glycerol) utilisation in a high throughput manner. All eight fungi grew in both cultivation systems, but growth was more variable and with more noise in the data in the Cytomat plate hotel than in the BioScreen. Specific growth rates between 0.01 (no added substrate) and 0.07 h-1 were measured for strains growing in the BioScreen and between 0.01 and 0.27 h-1 for strains in the plate hotel. Three strains, Dendryphiella salina LF304, Penicillium chrysogenum KF657 and Penicillium pinophilum LF458, consistently had higher specific growth rates on glucose and xylose in the plate hotel than in the BioScreen, but otherwise results were similar in the two systems. However, because of the noise in data from the plate hotel, the data obtained from it could only be used to distinguish between substrates which did or did not support growth, whereas data from BioScreen also provided information on substrate preference. Glucose was the preferred substrate for all strains, followed by xylose and galactose. Five strains also grew on glycerol. Therefore it was important to minimise the amount of glycerol introduced with the inoculum to avoid misinterpreting the results for growth on poor substrates. We concluded that both systems could provide physiological data with filamentous fungi, provided sufficient replicates are included in the measurements.
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Affiliation(s)
- Anu Tamminen
- VTT Technical Research Centre of Finland Ltd, Espoo, Finland
| | - Petrus Happonen
- VTT Technical Research Centre of Finland Ltd, Espoo, Finland
| | - Dorothee Barth
- VTT Technical Research Centre of Finland Ltd, Espoo, Finland
| | - Sami Holmström
- VTT Technical Research Centre of Finland Ltd, Espoo, Finland
| | - Marilyn G. Wiebe
- VTT Technical Research Centre of Finland Ltd, Espoo, Finland
- * E-mail:
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15
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Fernández de Ullivarri M, Arbulu S, Garcia-Gutierrez E, Cotter PD. Antifungal Peptides as Therapeutic Agents. Front Cell Infect Microbiol 2020; 10:105. [PMID: 32257965 PMCID: PMC7089922 DOI: 10.3389/fcimb.2020.00105] [Citation(s) in RCA: 115] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 02/27/2020] [Indexed: 12/17/2022] Open
Abstract
Fungi have been used since ancient times in food and beverage-making processes and, more recently, have been harnessed for the production of antibiotics and in processes of relevance to the bioeconomy. Moreover, they are starting to gain attention as a key component of the human microbiome. However, fungi are also responsible for human infections. The incidence of community-acquired and nosocomial fungal infections has increased considerably in recent decades. Antibiotic resistance development, the increasing number of immunodeficiency- and/or immunosuppression-related diseases and limited therapeutic options available are triggering the search for novel alternatives. These new antifungals should be less toxic for the host, with targeted or broader antimicrobial spectra (for diseases of known and unknown etiology, respectively) and modes of actions that limit the potential for the emergence of resistance among pathogenic fungi. Given these criteria, antimicrobial peptides with antifungal properties, i.e., antifungal peptides (AFPs), have emerged as powerful candidates due to their efficacy and high selectivity. In this review, we provide an overview of the bioactivity and classification of AFPs (natural and synthetic) as well as their mode of action and advantages over current antifungal drugs. Additionally, natural, heterologous and synthetic production of AFPs with a view to greater levels of exploitation is discussed. Finally, we evaluate the current and potential applications of these peptides, along with the future challenges relating to antifungal treatments.
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Affiliation(s)
- Miguel Fernández de Ullivarri
- APC Microbiome Ireland, University College Cork, Cork, Ireland.,Food Bioscience Department, Teagasc Food Research Centre, Fermoy, Ireland
| | - Sara Arbulu
- APC Microbiome Ireland, University College Cork, Cork, Ireland.,Food Bioscience Department, Teagasc Food Research Centre, Fermoy, Ireland
| | - Enriqueta Garcia-Gutierrez
- Food Bioscience Department, Teagasc Food Research Centre, Fermoy, Ireland.,Gut Microbes and Health, Quadram Institute Bioscience, Norwich, United Kingdom
| | - Paul D Cotter
- APC Microbiome Ireland, University College Cork, Cork, Ireland.,Food Bioscience Department, Teagasc Food Research Centre, Fermoy, Ireland
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16
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Khani S, Seyedjavadi SS, Hosseini HM, Goudarzi M, Valadbeigi S, Khatami S, Ajdary S, Eslamifar A, Amani J, Imani Fooladi AA, Razzaghi-Abyaneh M. Effects of the antifungal peptide Skh-AMP1 derived from Satureja khuzistanica on cell membrane permeability, ROS production, and cell morphology of conidia and hyphae of Aspergillus fumigatus. Peptides 2020; 123:170195. [PMID: 31704210 DOI: 10.1016/j.peptides.2019.170195] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Revised: 11/02/2019] [Accepted: 11/04/2019] [Indexed: 02/05/2023]
Abstract
Skh-AMP1 (GRTSKQELCTWERGSVRQADKTIAG) is an antifungal peptide isolated from Satureja khuzistanica which has been shown to have strong antifungal activity against Aspergillus and Candida species, but no obvious hemolytic effects or cell cytotoxicity in vitro. In the present study, Skh-AMP1 was synthesized, and its mode of action on the plasma membrane, mitochondria, and morphological and ultrastructural changes against conidia and hyphae of Aspergillus fumigatus were evaluated. The results indicated that Skh-AMP1 had sporicidal activities against the non-germinated conidia of A. fumigatus at concentrations of 40 and 80 μM. Skh-AMP1 induced the release of K+ and the uptake of propidium iodide and enhanced reactive oxygen species (ROS) production in the conidia and hyphae of the fungus. Scanning and transmission electron microscopy showed deformation and shrinkage of the hyphae and conidia, cell membrane disruption and detachment from the cell wall, microvesicle formation, vacuolation and depletion of cytoplasm and organelles of the hyphae of A. fumigatus exposed to 40-80 μM of the peptide. The results further demonstrated that the antifungal activity of Skh-AMP1 may be related to its ability to disrupt fungal cell membrane permeabilization and induce enhanced ROS production. Therefore, Skh-AMP1 can be introduced as a novel antifungal candidate for developing new therapeutic agents.
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Affiliation(s)
- Soghra Khani
- Department of Mycology, Pasteur Institute of Iran, Tehran, Iran
| | | | - Hamideh Mahmoodzadeh Hosseini
- Applied Microbiology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Mehdi Goudarzi
- Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Shohreh Khatami
- Department of Biochemistry, Pasteur Institute of Iran, Tehran, Iran
| | - Soheila Ajdary
- Department of Immunology, Pasteur Institute of Iran, Tehran, Iran
| | - Ali Eslamifar
- Department of Clinical Research, Pasteur Institute of Iran, Tehran, Iran
| | - Jafar Amani
- Applied Microbiology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Abbas Ali Imani Fooladi
- Applied Microbiology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran.
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17
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Yu Z, Cowan JA. Design and applications of catalytic metallodrugs containing the ATCUN motif. Med Chem 2020. [DOI: 10.1016/bs.adioch.2019.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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18
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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] [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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19
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Alexander JL, Thompson Z, Yu Z, Cowan JA. Cu-ATCUN Derivatives of Sub5 Exhibit Enhanced Antimicrobial Activity via Multiple Modes of Action. ACS Chem Biol 2019; 14:449-458. [PMID: 30742402 DOI: 10.1021/acschembio.8b01087] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Antimicrobial peptides (AMPs) are short, amphipathic peptides that are typically cationic in sequence and display broad-spectrum activity against bacteria, fungi, and protists. Herein, we report the effect of appending the amino terminal copper and nickel binding motif (ATCUN) to Sub5. The Cu-ATCUN derivatives show a two- to three-fold increase in antimicrobial activity for a variety of microbes, relative to Sub5, with MICs as low as 0.3 ± 0.1 μM toward Enterococcus faecium. Sub5 and the ATCUN derivatives bind both plasmid DNA and 16s A-site rRNA with low micromolar affinity. Native Sub5 and the metallopeptide derivatives were shown to promote damage against DNA to similar extents in cellular studies against both Escherichia coli and Staphylococcus epidermidis, with an almost threefold higher activity against the latter organism. Liposome experiments show that the metallopeptides have a greater affinity for model membranes of E. coli and S. aureus relative to Sub5, which correlates with their enhanced antimicrobial activity. Sub5 and the metalloderivatives also display no cytotoxicity toward adult human dermal fibroblasts. Addition of the ATCUN motif conferred the ability to promote lipid oxidation toward E. coli and S. epidermidis and enhanced membrane permeability, as evidenced by the extent of ATP leaked from cellular membranes relative to Sub5 alone. These data suggest that Cu-ATCUN derivatives inhibit microbes through multiple modes of action, resulting in an enhancement in their overall potency.
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Affiliation(s)
- Jessica L. Alexander
- Evans Laboratory of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Zechariah Thompson
- Evans Laboratory of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Zhen Yu
- Evans Laboratory of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - J. A. Cowan
- Evans Laboratory of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
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20
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e Silva KSF, da S Neto BR, Zambuzzi-Carvalho PF, de Oliveira CMA, Pires LB, Kato L, Bailão AM, Parente-Rocha JA, Hernández O, Ochoa JGM, de A Soares CM, Pereira M. Response of Paracoccidioides lutzii to the antifungal camphene thiosemicarbazide determined by proteomic analysis. Future Microbiol 2018; 13:1473-1496. [DOI: 10.2217/fmb-2018-0176] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Aim: To perform the proteomic profile of Paracoccidioides lutzii after treatment with the compound camphene thiosemicarbazide (TSC-C) in order to study its mode of action. Methods: Proteomic analysis was carried out after cells were incubated with TSC-C in a subinhibitory concentration. Validation of the proteomic results comprised the azocasein assay, western blot and determination of the susceptibility of a mutant to the compound. Results: Proteins related to metabolism, energy and protein fate were regulated after treatment. In addition, TSC-C reduces the proteolytic activity of the protein extract similarly to different types of protease inhibitors. Conclusion: TSC-C showed encouraging antifungal activity, working as a protease inhibitor and downregulating important pathways impairing the ability of the fungi cells to produce important precursors.
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Affiliation(s)
- Kleber SF e Silva
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Benedito R da S Neto
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Patrícia F Zambuzzi-Carvalho
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Cecília MA de Oliveira
- Laboratório de Produtos Naturais, Instituto de Química, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Ludmila B Pires
- Laboratório de Produtos Naturais, Instituto de Química, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Lucilia Kato
- Laboratório de Produtos Naturais, Instituto de Química, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Alexandre M Bailão
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Juliana A Parente-Rocha
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Orville Hernández
- Unidad de Biología Celular y Molecular, Corporación para Investigaciones Biológicas (CIB) & Escuela de Microbiología Universidad de Antioquia, Medellín, Colombia
| | - Juan GM Ochoa
- Unidad de Biología Celular y Molecular, Corporación para Investigaciones Biológicas (CIB) & Facultad de Medicina Universidad de Antioquia, Medellín, Colombia
| | - Célia M de A Soares
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Maristela Pereira
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
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21
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Alves TB, de Oliveira Ornela PH, de Oliveira AHC, Jorge JA, Guimarães LHS. Production and characterization of a thermostable antifungal chitinase secreted by the filamentous fungus Aspergillus niveus under submerged fermentation. 3 Biotech 2018; 8:369. [PMID: 30105194 DOI: 10.1007/s13205-018-1397-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 08/07/2018] [Indexed: 12/23/2022] Open
Abstract
The filamentous fungus Aspergillus niveus produced extracellular antifungal chitinase when cultured under submerged fermentation (SbmF) using crab shells as the carbon source. Maximal chitinase production was achieved at 192 h of cultivation using minimal medium containing 1% chitin. The enzyme was purified 1.97-fold with 40% recovery by ammonium sulfate precipitation and Sephadex G-100 gel filtration. The molecular mass was estimated to be 44 kDa by both 12% SDS-PAGE and Sepharose CL-6B gel filtration. Maximal A. niveus chitinase activity was obtained at 65 °C and pH 5.0. The enzyme was fully stable at 60 °C for up to 120 min and the enzymatic activity was increased by Mn2+. In the presence of reducing and denaturing compounds, the enzyme activity was not drastically affected. The chitinase was able to hydrolyze colloidal chitin, azure chitin, and 4-nitrophenyl N-acetyl-β-D glucosaminide; for the latter, the K0.5 and maximal velocity (Vmax) were 3.51 mM and 9.68 U/mg of protein, respectively. The A. niveus chitinase presented antifungal activity against Aspergillus niger (MIC = 84 µg/mL), A. fumigatus (MIC = 21 µg/mL), A. flavus (MIC = 24 µg/mL), A. phoenicis (MIC = 24 µg/mL), and Paecilomyces variotii (MIC = 21 µg/mL). The fungus A. niveus was able to produce a thermostable and denaturation-resistant chitinase able to inhibit fungal development, signaling its biotechnological potential.
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22
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Ravichandran G, Kumaresan V, Mahesh A, Dhayalan A, Arshad A, Arasu MV, Al-Dhabi NA, Pasupuleti M, Arockiaraj J. Bactericidal and fungistatic activity of peptide derived from GH18 domain of prawn chitinase 3 and its immunological functions during biological stress. Int J Biol Macromol 2018; 106:1014-1022. [DOI: 10.1016/j.ijbiomac.2017.08.098] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Revised: 08/16/2017] [Accepted: 08/16/2017] [Indexed: 02/06/2023]
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23
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Alexander JL, Yu Z, Cowan JA. Amino Terminal Copper and Nickel Binding Motif Derivatives of Ovispirin-3 Display Increased Antimicrobial Activity via Lipid Oxidation. J Med Chem 2017; 60:10047-10055. [PMID: 29172482 DOI: 10.1021/acs.jmedchem.7b01117] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Jessica L Alexander
- Evans Laboratory of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Zhen Yu
- Evans Laboratory of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - J. A Cowan
- Evans Laboratory of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
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24
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Recombinant Production and Antimicrobial Assessment of Beta Casein- IbAMP4 as a Novel Antimicrobial Polymeric Protein and its Synergistic Effects with Thymol. Int J Pept Res Ther 2017. [DOI: 10.1007/s10989-017-9605-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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25
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Fahimirad S, Abtahi H, Razavi SH, Alizadeh H, Ghorbanpour M. Production of Recombinant Antimicrobial Polymeric Protein Beta Casein-E 50-52 and Its Antimicrobial Synergistic Effects Assessment with Thymol. Molecules 2017; 22:molecules22060822. [PMID: 28561787 PMCID: PMC6152712 DOI: 10.3390/molecules22060822] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 05/08/2017] [Accepted: 05/11/2017] [Indexed: 01/18/2023] Open
Abstract
Accelerating emergence of antimicrobial resistance among food pathogens and consumers’ increasing demands for preservative-free foods are two contemporary challenging aspects within the food industry. Antimicrobial packaging and the use of natural preservatives are promising solutions. In the present study, we used beta-casein—one of the primary self-assembly proteins in milk with a high polymeric film production capability—as a fusion partner for the recombinant expression of E 50-52 antimicrobial peptide in Escherichia coli. The pET21a-BCN-E 50-52 construct was transformed to E. coli BL21 (DE3), and protein expression was induced under optimized conditions. Purified protein obtained from nickel affinity chromatography was refolded under optimized dialysis circumstances and concentrated to 1600 µg/mL fusion protein by ultrafiltration. Antimicrobial activities of recombinant BCN-E 50-52 performed against Escherichia coli, Salmonella typhimurium, Listeria monocytogenes, Staphylococcus aureus, Aspergillus flavus, and Candida albicans. Subsequently, the synergistic effects of BCN-E 50-52 and thymol were assayed. Results of checkerboard tests showed strong synergistic activity between two compounds. Time–kill and growth kinetic studies indicated a sharp reduction of cell viability during the first period of exposure, and SEM (scanning electron microscope) results validated the severe destructive effects of BCN E 50-52 and thymol in combination on bacterial cells.
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Affiliation(s)
- Shohreh Fahimirad
- Agriculture and Natural Resources Biotechnology Department, University of Tehran, Karaj 31587-11167, Iran; (S.F.); (S.H.R.); (H.A.)
| | - Hamid Abtahi
- Molecular and Medicine Research Center, Arak University of Medical Sciences, Arak, Molecular and Medicine Research Center, Arak University of Medical Sciences, Arak 38181-76941, Iran
- Correspondence: ; Tel.: +98-913-114-6154
| | - Seyed Hadi Razavi
- Agriculture and Natural Resources Biotechnology Department, University of Tehran, Karaj 31587-11167, Iran; (S.F.); (S.H.R.); (H.A.)
| | - Houshang Alizadeh
- Agriculture and Natural Resources Biotechnology Department, University of Tehran, Karaj 31587-11167, Iran; (S.F.); (S.H.R.); (H.A.)
| | - Mansour Ghorbanpour
- Department of Medicinal Plants, Faculty of Agriculture and Natural Resources, Arak University, Arak 3815688349, Iran;
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26
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Zhao C, Fernandez A, Avlonitis N, Vande Velde G, Bradley M, Read ND, Vendrell M. Searching for the Optimal Fluorophore to Label Antimicrobial Peptides. ACS COMBINATORIAL SCIENCE 2016; 18:689-696. [PMID: 27723293 DOI: 10.1021/acscombsci.6b00081] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
With the advent of antimicrobial resistance, there is an urgent need for new strategies to treat infectious diseases. Antimicrobial peptides are considered as promising candidates, and therefore there is a need to understand their mechanism of action in order to exploit their therapeutic potential. To this end, fluorescent analogs are powerful tools to analyze their behavior and subcellular localization in cells and in vivo. However, the conjugation of fluorophores to antimicrobial peptides, especially in short sequences, can impair their biological activity, making the selection of the fluorescent label an essential step in these studies. In the present work, we have systematically modified a model antifungal hexapeptide with a collection of fluorophores covering broad physicochemical and spectral properties. The resulting conjugates have been examined in two different fungal species, in terms of their activity and intracellular localization. The biological results confirm the influence of the different fluorescent moieties on the subcellular localization of antimicrobial sequences, and provides an insight on the optimal fluorophores to be used in the preparation of fluorescent peptides for different bioimaging assays.
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Affiliation(s)
- Can Zhao
- Manchester
Fungal Infection Group, Division of Infection, Immunity and Respiratory
Medicine, University of Manchester, CTF Building, Grafton Street, M13 9NT Manchester, United Kingdom
| | - Antonio Fernandez
- MRC/UoE
Centre for Inflammation Research, The University of Edinburgh, 47 Little
France Crescent, EH9 3FJ Edinburgh, United Kingdom
| | - Nicolaos Avlonitis
- EaStCHEM
School of Chemistry, The University of Edinburgh, West Mains Road, Edinburgh EH9 3FJ, United Kingdom
| | - Greetje Vande Velde
- Biomedical
MRI Unit/MoSAIC, Department of Imaging and Pathology, KU Leuven, Leuven, Belgium
| | - Mark Bradley
- EaStCHEM
School of Chemistry, The University of Edinburgh, West Mains Road, Edinburgh EH9 3FJ, United Kingdom
| | - Nick D. Read
- Manchester
Fungal Infection Group, Division of Infection, Immunity and Respiratory
Medicine, University of Manchester, CTF Building, Grafton Street, M13 9NT Manchester, United Kingdom
| | - Marc Vendrell
- MRC/UoE
Centre for Inflammation Research, The University of Edinburgh, 47 Little
France Crescent, EH9 3FJ Edinburgh, United Kingdom
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Chan WT, Espinosa M. The Streptococcus pneumoniae pezAT Toxin-Antitoxin System Reduces β-Lactam Resistance and Genetic Competence. Front Microbiol 2016; 7:1322. [PMID: 27610103 PMCID: PMC4997998 DOI: 10.3389/fmicb.2016.01322] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 08/10/2016] [Indexed: 12/11/2022] Open
Abstract
Chromosomally encoded Type II Toxin–Antitoxin operons are ubiquitous in bacteria and archaea. Antitoxins neutralize the toxic effect of cognate Toxins by protein–protein interactions and sequestering the active residues of the Toxin. Toxins target essential bacterial processes, mostly translation and replication. However, one class apart is constituted by the PezAT pair because the PezT toxin target cell wall biosynthesis. Here, we have examined the role of the pezAT toxin–antitoxin genes in its natural host, the pathogenic bacterium Streptococcus pneumoniae. The pezAT operon on Pneumococcal Pathogenicity Island 1 was deleted from strain R6 and its phenotypic traits were compared with those of the wild type. The mutant cells formed shorter chains during exponential phase, leading to increased colony-forming units. At stationary phase, the mutant was more resilient to lysis. Importantly, the mutant exhibited higher resistance to antibiotics targeting cell walls (β-lactams), but not to antibiotics acting at other levels. In addition, the mutants also showed enhanced genetic competence. We suggest that PezAT participates in a subtle equilibrium between loss of functions (resistance to β-lactams and genetic competence) and gain of other traits (virulence).
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Affiliation(s)
- Wai T Chan
- Bacterial Gene Expression and Gene Transfer, Molecular Microbiology and Infectious Biology, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas Madrid, Spain
| | - Manuel Espinosa
- Bacterial Gene Expression and Gene Transfer, Molecular Microbiology and Infectious Biology, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas Madrid, Spain
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Puig M, Moragrega C, Ruz L, Calderón CE, Cazorla FM, Montesinos E, Llorente I. Interaction of antifungal peptide BP15 with Stemphylium vesicarium , the causal agent of brown spot of pear. Fungal Biol 2016; 120:61-71. [DOI: 10.1016/j.funbio.2015.10.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 10/13/2015] [Accepted: 10/23/2015] [Indexed: 02/08/2023]
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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. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1858:1024-33. [PMID: 26687790 DOI: 10.1016/j.bbamem.2015.12.013] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [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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30
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Chadha S, Kale S. Simple fluorescence-based high throughput cell viability assay for filamentous fungi. Lett Appl Microbiol 2015; 61:238-44. [DOI: 10.1111/lam.12460] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 06/09/2015] [Accepted: 06/18/2015] [Indexed: 01/28/2023]
Affiliation(s)
- S. Chadha
- Nuclear Agriculture and Biotechnology Division; Bhabha Atomic Research Centre; Mumbai India
| | - S.P. Kale
- Nuclear Agriculture and Biotechnology Division; Bhabha Atomic Research Centre; Mumbai India
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Functional Analysis of Sterol Transporter Orthologues in the Filamentous Fungus Aspergillus nidulans. EUKARYOTIC CELL 2015; 14:908-21. [PMID: 26116213 DOI: 10.1128/ec.00027-15] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2015] [Accepted: 06/24/2015] [Indexed: 11/20/2022]
Abstract
Polarized growth in filamentous fungi needs a continuous supply of proteins and lipids to the growing hyphal tip. One of the important membrane compounds in fungi is ergosterol. At the apical plasma membrane ergosterol accumulations, which are called sterol-rich plasma membrane domains (SRDs). The exact roles and formation mechanism of the SRDs remained unclear, although the importance has been recognized for hyphal growth. Transport of ergosterol to hyphal tips is thought to be important for the organization of the SRDs. Oxysterol binding proteins, which are conserved from yeast to human, are involved in nonvesicular sterol transport. In Saccharomyces cerevisiae seven oxysterol-binding protein homologues (OSH1 to -7) play a role in ergosterol distribution between closely located membranes independent of vesicle transport. We found five homologous genes (oshA to oshE) in the filamentous fungi Aspergillus nidulans. The functions of OshA-E were characterized by gene deletion and subcellular localization. Each gene-deletion strain showed characteristic phenotypes and different sensitivities to ergosterol-associated drugs. Green fluorescent protein-tagged Osh proteins showed specific localization in the late Golgi compartments, puncta associated with the endoplasmic reticulum, or diffusely in the cytoplasm. The genes expression and regulation were investigated in a medically important species Aspergillus fumigatus, as well as A. nidulans. Our results suggest that each Osh protein plays a role in ergosterol distribution at distinct sites and contributes to proper fungal growth.
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Mahindra A, Bagra N, Wangoo N, Khan SI, Jacob MR, Jain R. Discovery of Short Peptides Exhibiting High Potency against Cryptococcus neoformans. ACS Med Chem Lett 2014; 5:315-20. [PMID: 24900833 DOI: 10.1021/ml500011v] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Accepted: 01/15/2014] [Indexed: 01/06/2023] Open
Abstract
Rapid increase in the emergence of resistance against existing antifungal drugs created a need to discover new structural classes of antifungal agents. In this study we describe the synthesis of a new structural class of short antifungal peptidomimetcis, their activity, and plausible mechanism of action. The results of the study show that peptides 11e and 11f are more potent than the control drug amphotericin B, with no cytotoxicity to human cancer cells and noncancerous mammalian kidney cells. The selectivity of peptides to fungus is depicted by transmission electron microscopy studies, and it revealed that 11e possibly disrupts the model membrane of the fungal pathogen.
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Affiliation(s)
- Amit Mahindra
- Department
of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S. A. S. Nagar, Punjab 160 062, India
| | - Nitin Bagra
- Department
of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S. A. S. Nagar, Punjab 160 062, India
| | - Nishima Wangoo
- Center
for Nanoscience and Nanotechnology, Panjab University, Sector 14, Chandigarh 160 014, India
| | - Shabana I. Khan
- National
Center for Natural Products Research, School of Pharmacy, The University of Mississippi, University, Mississippi 38677, United States
| | - Melissa R. Jacob
- National
Center for Natural Products Research, School of Pharmacy, The University of Mississippi, University, Mississippi 38677, United States
| | - Rahul Jain
- Department
of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S. A. S. Nagar, Punjab 160 062, India
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Fungicidal mechanisms of cathelicidins LL-37 and CATH-2 revealed by live-cell imaging. Antimicrob Agents Chemother 2014; 58:2240-8. [PMID: 24492359 DOI: 10.1128/aac.01670-13] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Antifungal mechanisms of action of two cathelicidins, chicken CATH-2 and human LL-37, were studied and compared with the mode of action of the salivary peptide histatin 5 (Hst5). Candida albicans was used as a model organism for fungal pathogens. Analysis by live-cell imaging showed that the peptides kill C. albicans rapidly. CATH-2 is the most active peptide and kills C. albicans within 5 min. Both cathelicidins induce cell membrane permeabilization and simultaneous vacuolar expansion. Minimal fungicidal concentrations (MFC) are in the same order of magnitude for all three peptides, but the mechanisms of antifungal activity are very different. The activity of cathelicidins is independent of the energy status of the fungal cell, unlike Hst5 activity. Live-cell imaging using fluorescently labeled peptides showed that both CATH-2 and LL-37 quickly localize to the C. albicans cell membrane, while Hst5 was mainly directed to the fungal vacuole. Small amounts of cathelicidins internalize at sub-MFCs, suggesting that intracellular activities of the peptide could contribute to the antifungal activity. Analysis by flow cytometry indicated that CATH-2 significantly decreases C. albicans cell size. Finally, electron microscopy showed that CATH-2 affects the integrity of the cell membrane and nuclear envelope. It is concluded that the general mechanisms of action of both cathelicidins are partially similar (but very different from that of Hst5). CATH-2 has unique features and possesses antifungal potential superior to that of LL-37.
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Torcato IM, Huang YH, Franquelim HG, Gaspar DD, Craik DJ, Castanho MARB, Henriques ST. The antimicrobial activity of Sub3 is dependent on membrane binding and cell-penetrating ability. Chembiochem 2013; 14:2013-22. [PMID: 24038773 DOI: 10.1002/cbic.201300274] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Indexed: 12/21/2022]
Abstract
Because of their high activity against microorganisms and low cytotoxicity, cationic antimicrobial peptides (AMPs) have been explored as the next generation of antibiotics. Although they have common structural features, the modes of action of AMPs are extensively debated, and a single mechanism does not explain the activity of all AMPs reported so far. Here we investigated the mechanism of action of Sub3, an AMP previously designed and optimised from high-throughput screening with bactenecin as the template. Sub3 has potent activity against Gram-negative and Gram-positive bacteria as well as against fungi, but its mechanism of action has remained elusive. By using AFM imaging, ζ potential, flow cytometry and fluorescence methodologies with model membranes and bacterial cells, we found that, although the mechanism of action involves membrane targeting, Sub3 internalises inside bacteria at lethal concentrations without permeabilising the membrane, thus suggesting that its antimicrobial activity might involve both the membrane and intracellular targets. In addition, we found that Sub3 can be internalised into human cells without being toxic. As some bacteria are able to survive intracellularly and consequently evade host defences and antibiotic treatment, our findings suggest that Sub3 could be useful as an intracellular antimicrobial agent for infections that are notoriously difficult to treat.
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Affiliation(s)
- Inês M Torcato
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Av. Prof. Egas Moniz, 1649-028 Lisbon (Portugal)
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Muñoz A, Harries E, Contreras-Valenzuela A, Carmona L, Read ND, Marcos JF. Two functional motifs define the interaction, internalization and toxicity of the cell-penetrating antifungal peptide PAF26 on fungal cells. PLoS One 2013; 8:e54813. [PMID: 23349973 PMCID: PMC3549957 DOI: 10.1371/journal.pone.0054813] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Accepted: 12/17/2012] [Indexed: 11/19/2022] Open
Abstract
The synthetic, cell penetrating hexapeptide PAF26 (RKKWFW) is antifungal at low micromolar concentrations and has been proposed as a model for cationic, cell-penetrating antifungal peptides. Its short amino acid sequence facilitates the analysis of its structure-activity relationships using the fungal models Neurospora crassa and Saccharomyces cerevisiae, and human and plant pathogens Aspergillus fumigatus and Penicillium digitatum, respectively. Previously, PAF26 at low fungicidal concentrations was shown to be endocytically internalized, accumulated in vacuoles and then actively transported into the cytoplasm where it exerts its antifungal activity. In the present study, two PAF26 derivatives, PAF95 (AAAWFW) and PAF96 (RKKAAA), were designed to characterize the roles of the N-terminal cationic and the C-terminal hydrophobic motifs in PAF26's mode-of-action. PAF95 and PAF96 exhibited substantially reduced antifungal activity against all the fungi analyzed. PAF96 localized to fungal cell envelopes and was not internalized by the fungi. In contrast, PAF95 was taken up into vacuoles of N. crassa, wherein it accumulated and was trapped without toxic effects. Also, the PAF26 resistant Δarg1 strain of S. cerevisiae exhibited increased PAF26 accumulation in vacuoles. Live-cell imaging of GFP-labelled nuclei in A. fumigatus showed that transport of PAF26 from the vacuole to the cytoplasm was followed by nuclear breakdown and dissolution. This work demonstrates that the amphipathic PAF26 possesses two distinct motifs that allow three stages in its antifungal action to be defined: (i) its interaction with the cell envelope; (ii) its internalization and transport to vacuoles mediated by the aromatic hydrophobic domain; and (iii) its transport from vacuoles to the cytoplasm. Significantly, cationic residues in PAF26 are important not only for the electrostatic attraction and interaction with the fungal cell but also for transport from the vacuole to the cytoplasm, which coincides with cell death. Peptide containment within vacuoles preserves fungal cells from peptide toxicity.
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Affiliation(s)
- Alberto Muñoz
- Fungal Cell Biology Group, Institute of Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
| | - Eleonora Harries
- Fungal Cell Biology Group, Institute of Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
- Department of Food Science, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Paterna, Valencia, Spain
| | | | - Lourdes Carmona
- Department of Food Science, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Paterna, Valencia, Spain
| | - Nick D. Read
- Fungal Cell Biology Group, Institute of Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
- * E-mail: (JFM); (NDR)
| | - Jose F. Marcos
- Department of Food Science, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Paterna, Valencia, Spain
- * E-mail: (JFM); (NDR)
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37
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Muñoz A, Gandía M, Harries E, Carmona L, Read ND, Marcos JF. Understanding the mechanism of action of cell-penetrating antifungal peptides using the rationally designed hexapeptide PAF26 as a model. FUNGAL BIOL REV 2013. [DOI: 10.1016/j.fbr.2012.10.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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38
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Muñoz A, Read ND. Live-cell imaging and analysis shed light on the complexity and dynamics of antimicrobial Peptide action. Front Immunol 2012; 3:248. [PMID: 22912634 PMCID: PMC3418630 DOI: 10.3389/fimmu.2012.00248] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 07/25/2012] [Indexed: 01/04/2023] Open
Affiliation(s)
- Alberto Muñoz
- Fungal Cell Biology Group, Institute of Cell Biology, University of Edinburgh Edinburgh, UK
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39
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Muñoz A, Marcos JF, Read ND. Concentration-dependent mechanisms of cell penetration and killing by the de novo designed antifungal hexapeptide PAF26. Mol Microbiol 2012; 85:89-106. [DOI: 10.1111/j.1365-2958.2012.08091.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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40
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Ntwasa M, Goto A, Kurata S. Coleopteran antimicrobial peptides: prospects for clinical applications. Int J Microbiol 2012; 2012:101989. [PMID: 22500175 PMCID: PMC3303552 DOI: 10.1155/2012/101989] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Revised: 11/02/2011] [Accepted: 12/05/2011] [Indexed: 12/20/2022] Open
Abstract
Antimicrobial peptides (AMPs) are activated in response to septic injury and have important roles in vertebrate and invertebrate immune systems. AMPs act directly against pathogens and have both wound healing and antitumor activities. Although coleopterans comprise the largest and most diverse order of eukaryotes and occupy an earlier branch than Drosophila in the holometabolous lineage of insects, their immune system has not been studied extensively. Initial research reports, however, indicate that coleopterans possess unique immune response mechanisms, and studies of these novel mechanisms may help to further elucidate innate immunity. Recently, the complete genome sequence of Tribolium was published, boosting research on coleopteran immunity and leading to the identification of Tribolium AMPs that are shared by Drosophila and mammals, as well as other AMPs that are unique. AMPs have potential applicability in the development of vaccines. Here, we review coleopteran AMPs, their potential impact on clinical medicine, and the molecular basis of immune defense.
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Affiliation(s)
- Monde Ntwasa
- School of Molecular and Cell Biology, University of the Witwatersrand, Wits 2050, South Africa
| | - Akira Goto
- Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai 980-8578, Japan
| | - Shoichiro Kurata
- Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai 980-8578, Japan
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Takeshita N, Diallinas G, Fischer R. The role of flotillin FloA and stomatin StoA in the maintenance of apical sterol-rich membrane domains and polarity in the filamentous fungus Aspergillus nidulans. Mol Microbiol 2012; 83:1136-52. [PMID: 22329814 DOI: 10.1111/j.1365-2958.2012.07996.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Apical sterol-rich plasma membrane domains (SRDs), which can be viewed using the sterol-binding fluorescent dye filipin, are gaining attention for their important roles in polarized growth of filamentous fungi. The microdomain scaffolding protein flotillin/reggie and related stomatin were thought to be good candidates involved in the formation of SRDs. Here, we show that the flotillin/reggie orthologue FloA tagged with GFP localized as stable dots along the plasma membrane except hyphal tips. Deletion of floA reduced the growth rate, often resulted in irregularly shaped hyphae and impaired SRDs. In contrast, the stomatin orthologue StoA, tagged with GFP, localized at the cortex of young branch tips and at the subapical cortex in long hyphal tips, and was transported bi-directionally along microtubules on endosomes. Deletion of stoA resulted in irregular hyphal morphology and increased branching especially in young hyphae, but did not obviously affect SRDs. Double deletion of floA and stoA enhanced the defects of growth and hyphal morphology. Our data suggest that the plasma membrane of hyphal tips and in subapical regions are distinct and that FloA is involved in membrane compartmentalization and probably indirectly in SRD maintenance.
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Affiliation(s)
- Norio Takeshita
- Karlsruhe Institute of Technology, Institute for Applied Biosciences, Dept. of Microbiology, Hertzstrasse 16, D-76187 Karlsruhe, Germany.
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Monteiro MC, de la Cruz M, Cantizani J, Moreno C, Tormo JR, Mellado E, De Lucas JR, Asensio F, Valiante V, Brakhage AA, Latgé JP, Genilloud O, Vicente F. A new approach to drug discovery: high-throughput screening of microbial natural extracts against Aspergillus fumigatus using resazurin. ACTA ACUST UNITED AC 2012; 17:542-9. [PMID: 22233645 DOI: 10.1177/1087057111433459] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Natural products are an inexhaustible source for drug discovery. However, the validation and selection of primary screening assays are vital to guarantee a selection of extracts or molecules with relevant pharmacological action and worthy of following up. The assay must be rapid, simple, easy to implement, and produce quick results and preferably at a low cost. In this work, we developed and validated a colorimetric microtiter assay using the resazurin viability dye. The parameters of the resazurin method for high-throughput screening (HTS) using natural extracts against Aspergillus fumigatus were optimized and set up. The extracts plus RPMI-1640 modified medium containing the spores and 0.002% resazurin were added per well. The fluorescence was read after 24 to 30 h of incubation. The resazurin proved to be as suitable as Alamar Blue for determining the minimal inhibitory concentration of different antifungals against A. fumigatus and effective to analyze fungicidal and fungistatic compounds. An HTS of 12 000 microbial extracts was carried out against two A. fumigatus strains, and 2.7% of the extracts displayed antifungal activity. Our group has been the first to use this methodology for screening a collection of natural extracts to identify compounds with antifungal activity against the medically important human pathogen A. fumigatus.
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Affiliation(s)
- Maria Cândida Monteiro
- Fundación MEDINA, Centro de Excelencia en Investigación de Medicamentos Innovadores en Andalucía, Armilla, Granada, Spain.
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López-Abarrategui C, Alba A, Silva ON, Reyes-Acosta O, Vasconcelos IM, Oliveira JTA, Migliolo L, Costa MP, Costa CR, Silva MRR, Garay HE, Dias SC, Franco OL, Otero-González AJ. Functional characterization of a synthetic hydrophilic antifungal peptide derived from the marine snail Cenchritis muricatus. Biochimie 2011; 94:968-74. [PMID: 22210491 DOI: 10.1016/j.biochi.2011.12.016] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Accepted: 12/17/2011] [Indexed: 11/18/2022]
Abstract
Antimicrobial peptides have been found in mollusks and other sea animals. In this report, a crude extract of the marine snail Cenchritis muricatus was evaluated against human pathogens responsible for multiple deleterious effects and diseases. A peptide of 1485.26 Da was purified by reversed-phase HPLC and functionally characterized. This trypsinized peptide was sequenced by MS/MS technology, and a sequence (SRSELIVHQR), named Cm-p1 was recovered, chemically synthesized and functionally characterized. This peptide demonstrated the capacity to prevent the development of yeasts and filamentous fungi. Otherwise, Cm-p1 displayed no toxic effects against mammalian cells. Molecular modeling analyses showed that this peptide possible forms a single hydrophilic α-helix and the probable cationic residue involved in antifungal activity action is proposed. The data reported here demonstrate the importance of sea animals peptide discovery for biotechnological tools development that could be useful in solving human health and agribusiness problems.
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Affiliation(s)
- Carlos López-Abarrategui
- Centro de Estudios de Proteínas, Facultad de Biología, Universidad de La Habana, Calle 25 entre J e I, Vedado, Municipio Plaza, La Habana 10400, Cuba
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