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Alav I, Pordelkhaki P, de Resende PE, Partington H, Gibbons S, Lord RM, Buckner MMC. Cobalt complexes modulate plasmid conjugation in Escherichia coli and Klebsiella pneumoniae. Sci Rep 2024; 14:8103. [PMID: 38582880 PMCID: PMC10998897 DOI: 10.1038/s41598-024-58895-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 04/04/2024] [Indexed: 04/08/2024] Open
Abstract
Antimicrobial resistance genes (ARG), such as extended-spectrum β-lactamase (ESBL) and carbapenemase genes, are commonly carried on plasmids. Plasmids can transmit between bacteria, disseminate globally, and cause clinically important resistance. Therefore, targeting plasmids could reduce ARG prevalence, and restore the efficacy of existing antibiotics. Cobalt complexes possess diverse biological activities, including antimicrobial and anticancer properties. However, their effect on plasmid conjugation has not been explored yet. Here, we assessed the effect of four previously characterised bis(N-picolinamido)cobalt(II) complexes lacking antibacterial activity on plasmid conjugation in Escherichia coli and Klebsiella pneumoniae. Antimicrobial susceptibility testing of these cobalt complexes confirmed the lack of antibacterial activity in E. coli and K. pneumoniae. Liquid broth and solid agar conjugation assays were used to screen the activity of the complexes on four archetypical plasmids in E. coli J53. The cobalt complexes significantly reduced the conjugation of RP4, R6K, and R388 plasmids, but not pKM101, on solid agar in E. coli J53. Owing to their promising activity, the impact of cobalt complexes was tested on the conjugation of fluorescently tagged extended-spectrum β-lactamase encoding pCTgfp plasmid in E. coli and carbapenemase encoding pKpQILgfp plasmid in K. pneumoniae, using flow cytometry. The complexes significantly reduced the conjugation of pKpQILgfp in K. pneumoniae but had no impact on pCTgfp conjugation in E. coli. The cobalt complexes did not have plasmid-curing activity, suggesting that they target conjugation rather than plasmid stability. To our knowledge, this is the first study to report reduced conjugation of clinically relevant plasmids with cobalt complexes. These cobalt complexes are not cytotoxic towards mammalian cells and are not antibacterial, therefore they could be optimised and employed as inhibitors of plasmid conjugation.
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Affiliation(s)
- Ilyas Alav
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Parisa Pordelkhaki
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Pedro Ernesto de Resende
- School of Pharmacy, Faculty of Science, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Hannah Partington
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Simon Gibbons
- Natural & Medical Sciences Research Center, University of Nizwa, Birkat Al Mauz, P.O. Box 33, Nizwa, 616, Oman
| | - Rianne M Lord
- School of Chemistry, Faculty of Science, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Michelle M C Buckner
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK.
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Munshi T, Gupta A, Evangelopoulos D, Guzman JD, Gibbons S, Keep NH, Bhakta S. Correction: Characterisation of ATP-Dependent Mur Ligases Involved in the Biogenesis of Cell Wall Peptidoglycan in Mycobacterium tuberculosis. PLoS One 2024; 19:e0301375. [PMID: 38530839 DOI: 10.1371/journal.pone.0301375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024] Open
Abstract
[This corrects the article DOI: 10.1371/journal.pone.0060143.].
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3
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Gibbons S, Dexter F, Loftus RW, Brown JR, Wanta BT, Charnin JE. The relative efficacy of multiple syringe tip disinfection techniques against virulent staphylococcus contamination. J Hosp Infect 2024; 145:142-147. [PMID: 38272124 DOI: 10.1016/j.jhin.2024.01.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 12/19/2023] [Accepted: 01/11/2024] [Indexed: 01/27/2024]
Abstract
BACKGROUND A recent study confirmed significant contamination of syringe tips following routine anaesthesia practice of at least 6 h in duration. AIM We assessed the relative efficacy of clinically relevant syringe tip disinfection techniques following contamination with the hyper transmissible and more pathogenic Staphylococcus aureus sequence type 5 (S. aureus ST5) strain characteristic associated with increased strength of biofilm formation and greater desiccation tolerance. METHODS Syringe tips (N=40) contaminated with S. aureus ST5 were randomized to 70% isopropyl pads with 10 or 60 s of drying time, scrubbing alcohol disinfection caps with 10 or 60 s of dwell time, or to non-scrubbing alcohol disinfection caps with 60 s of dwell time. The primary outcome was residual 24-h colony forming units (cfu) >10. RESULTS Scrubbing disinfection caps were more effective than alcohol pads (25% (12/48) <10 cfu for scrubbing caps (10- or 60-s dwell times) vs 0% (0/48) <10 cfu for alcohol pads (10 or 60 s of drying time), Holm-Sidak adjusted P=0.0016). Scrubbing disinfection caps were more effective than non-scrubbing alcohol disinfection caps (25% (12/48) <10 cfu for scrubbing alcohol caps (10- or 60-s dwell times) vs 2% (1/48) for non-scrubbing alcohol caps (60-s dwell time), adjusted P=0.0087). CONCLUSIONS Scrubbing alcohol caps are more effective than alcohol pads or non-scrubbing disinfecting caps for microbial reduction of syringe tips contaminated with the more pathogenic S. aureus ST5.
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Affiliation(s)
- S Gibbons
- Department of Anesthesia, University of Iowa, Iowa City, IA, USA
| | - F Dexter
- Department of Anesthesia, University of Iowa, Iowa City, IA, USA
| | - R W Loftus
- Department of Anesthesia, University of Iowa, Iowa City, IA, USA; Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA
| | - J R Brown
- Dartmouth Center for Implementation Science, Departments of Epidemiology Biomedical Data Science, Health Policy and Clinical Practice, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - B T Wanta
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA
| | - J E Charnin
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA.
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Xiao CY, Lan JE, Liu X, Sun ZL, Li XJ, Yin YH, Gibbons S, Mu Q. Acetylenic spiroketal enol ethers from Artemisia rupestris and their synergistic antibacterial effects on methicillin-resistant Staphylococcus aureus. Nat Prod Res 2024; 38:589-593. [PMID: 36855235 DOI: 10.1080/14786419.2023.2183952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 02/19/2023] [Indexed: 03/02/2023]
Abstract
Synergistic bioassay-guided isolation of the extracts of Artemisia rupestris L, which belongs to the family Asteraceae, afforded two acetylenic spiroketal enol ethers, namely rupesdiynes A (1) and B (2). Their structures were determined based on spectroscopic analysis and experimental and calculated ECD investigations. The two compounds exhibited synergistic activity and were able to reduce the minimum inhibitory concentration (MIC) of oxacillin four-fold, with a fractional inhibitory concentration index (FICI) of 0.5 in combination with oxacillin against the oxacillin-resistant EMRSA-16. Biofilm formation inhibitory and Ethidium bromide (EtBr) efflux assay were further employed to verify the possible mechanism of the synergistic antibacterial effect. Additionally, molecular docking studies were conducted to investigate the binding affinities of the two compounds with penicillin-binding protein 2a (PBP2a) of EMRSA-16. Taken together, rupesdiynes A (1) and rupesdiyne B (2) showed moderate synergistic activity against EMRSA-16 with oxacillin via inhibiting biofilm formation and efflux pump activity, respectively.
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Affiliation(s)
| | - Jiang-Er Lan
- School of Pharmacy, Fudan University, Shanghai, China
| | - Xiao Liu
- School of Pharmacy, Fudan University, Shanghai, China
| | - Zhong-Lin Sun
- School of Pharmacy, Fudan University, Shanghai, China
| | - Xiao-Jin Li
- Traditional Chinese Medicine and Ethnomedicine Institute of Xinjiang, Wulumuqi, China
| | - Yi-Han Yin
- School of Pharmacy, Fudan University, Shanghai, China
| | - Simon Gibbons
- Centre for Natural Products Discovery, School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Qing Mu
- School of Pharmacy, Fudan University, Shanghai, China
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Xiao CY, Huang J, Liu X, Sun ZL, Li RS, Li LY, Gibbons S, Mu Q. Natural Product BO-1 as an Inner Responsive Molecule Inhibits Antimicrobial-Resistant Staphylococcus aureus via Synergism. ACS Infect Dis 2023; 9:1523-1533. [PMID: 37417322 DOI: 10.1021/acsinfecdis.3c00066] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/08/2023]
Abstract
Multidrug-resistant Staphylococcus aureus, a Gram-positive bacterium that causes several difficult-to-treat human infections, is a considerable threat to global healthcare. We hypothesize that there exist inner responsive molecules (IRMs) which can function synergistically with antibiotics to restore the sensitivity of resistant bacteria to existing antibiotics without inducing new antibiotic resistance. An investigation of the extracts of the Chinese medicinal herb Piper betle L. led to the isolation of six benzoate esters, BO-1-BO-6. Among these, BO-1 as a distinct IRM displayed considerable synergism by potentiating antibacterial activity against five antibiotic-resistant S. aureus strains. Mechanistic studies demonstrated that BO-1 acted as a suppressing drug resistance IRM via inhibiting efflux activity. A combination of BO-1 with ciprofloxacin significantly inhibited resistance to this antibiotic and reversed its resistance in the S. aureus strain. Furthermore, BO-1 effectively enhanced the activity of ciprofloxacin against the efflux fluoroquinolone-resistant S. aureus strain SA1199B that caused infection in two animal models and significantly decreased the inflammatory factors IL-6 and C-reactive protein of the infected mice, thereby showing the practice utility of this approach.
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Affiliation(s)
- Chuan-Yun Xiao
- School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Jiao Huang
- School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Xiao Liu
- School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Zhong-Lin Sun
- School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Rong-Sheng Li
- School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Ling-Yun Li
- School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Simon Gibbons
- Centre for Natural Products Discovery, School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool L3 3AF, U.K
| | - Qing Mu
- School of Pharmacy, Fudan University, Shanghai 201203, China
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Alqahtani O, Stapleton P, Gibbons S. Production of antibacterial compounds using Bacillus spp. isolated from thermal springs in Saudi Arabia. Saudi Pharm J 2023; 31:1237-1243. [PMID: 37284417 PMCID: PMC10239688 DOI: 10.1016/j.jsps.2023.05.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 05/12/2023] [Indexed: 06/08/2023] Open
Abstract
Seventeen water samples were collected from four different thermal springs in Saudi Arabia. Microbiological assays were used to assess the antibacterial activities of bacterial colonies against antibiotic-resistant and susceptible-bacterial strains, and 16S rRNA gene sequencing was used to identify the genus and species of these antibiotic-producing bacteria. Chromatography and spectroscopy were used to separate the active compounds and help figuring out what their structures were. Four compounds were isolated using bacteria: N-acetyltryptamine (1), isovaleric acid (2), ethyl-4-ethoxybenzoate (3) and phenylacetic acid (4). Compounds 1, 2 and 4 were produced from Bacillus pumilus and 3 was from Bacillus licheniformis (AH-E1). The outcomes of the minimum inhibitory concentrations (MICs) showed that all pure compounds produced in this work had antibacterial activities against Gram-positive pathogens (between 128 mg/L and 512 mg/L compared to the control) and compound 2 had activity against E. coli.
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Affiliation(s)
- Omaish Alqahtani
- Department of Pharmacognosy, College of Pharmacy, Najran University, Najran, Saudi Arabia
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK
| | - Paul Stapleton
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK
| | - Simon Gibbons
- Centre for Natural Products Discovery (CNPD), Liverpool John Moores University, Liverpool L3 3AF, England, UK
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de Resende PE, Nisler J, Voller J, Kadlecová A, Gibbons S. Antimicrobial and anthelmintic activities of aryl urea agents. J Glob Antimicrob Resist 2023; 33:114-119. [PMID: 36906171 DOI: 10.1016/j.jgar.2023.02.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 01/03/2023] [Accepted: 02/23/2023] [Indexed: 03/12/2023] Open
Abstract
OBJECTIVES This study aimed to characterise compounds with activity against carbapenemase-expressing Gram-negative bacteria and nematodes and evaluate their cytotoxicity to non-cancerous human cells. METHODS The antimicrobial activity and toxicity of a series of phenyl-substituted urea derivatives were evaluated using broth microdilution, chitinase, and resazurin reduction assays. RESULTS The effects of different substitutions present on the nitrogen atoms of the urea backbone were investigated. Several compounds were active against Staphylococcus aureus and Escherichia coli control strains. Specifically, derivatives 7b, 11b, and 67d exhibited antimicrobial activity against Klebsiella pneumoniae 16, a carbapenemase-producing Enterobacteriaceae species, with minimum inhibitory concentration (MIC) values of 100, 50, and 72 µM (32, 64, and 32 mg/L), respectively. In addition, the MICs obtained against a multidrug-resistant E. coli strain were 100, 50, and 36 µM (32, 16, and 16 mg/L) for the same compounds, respectively. Furthermore, the urea derivatives 18b, 29b, 50c, 51c, 52c, 55c-59c, and 62c were very active towards the nematode Caenorhabditis elegans. CONCLUSIONS Testing on non-cancerous human cell lines suggested that some of the compounds have the potential to affect bacteria, especially helminths, with limited cytotoxicity to humans. Given the simplicity of synthesis for this class of compounds and their potency against Gram-negative, carbapenemase-expressing K. pneumoniae, aryl ureas possessing the 3,5-dichloro-phenyl group certainly warrant further investigation to exploit their selectivity.
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Affiliation(s)
- Pedro Ernesto de Resende
- School of Pharmacy, Faculty of Science, University of East Anglia, Norwich Research Park, Norwich, United Kingdom.
| | - Jaroslav Nisler
- Isotope Laboratory, Institute of Experimental Botany, The Czech Academy of Sciences, Prague, Czech Republic
| | - Jiří Voller
- Department of Experimental Biology, Faculty of Science, Palacký University, Olomouc, Czech Republic; Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University, Olomouc, Czech Republic
| | - Alena Kadlecová
- Department of Experimental Biology, Faculty of Science, Palacký University, Olomouc, Czech Republic
| | - Simon Gibbons
- Centre for Natural Products Discovery (CNPD), School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, United Kingdom
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Hanafi MMM, Yaakob H, Gibbons S, Prieto JM. In Vitro Pro-Apoptotic and Anti-Migratory Effects of Marantodes pumilum (syn. Labisia pumila) Extracts on Human Prostate Cancer Cell Lines: Bioguided Isolation of 5-Henicosene-1-yl-resorcinol. Plants (Basel) 2023; 12:1576. [PMID: 37050202 PMCID: PMC10097395 DOI: 10.3390/plants12071576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 03/17/2023] [Accepted: 03/28/2023] [Indexed: 06/19/2023]
Abstract
This study aims to evaluate the in vitro cytotoxic and anti-migratory effects of Marantodes pumilum Blume Kuntze plant extracts on prostate cancer cells, identify the active compound/s, and characterize their mechanism of action. The crude methanolic extract was partitioned into n-hexane (MPh), chloroform (MPc), and aqueous (MPa) extracts. Antiproliferative fractions (IC50 < 30 μg/mL based on SRB staining of LNCaP and PC3 cell lines) were further fractionated. Active compound/s were identified using spectroscopic methods. In vitro mechanistic studies on PC3 cells included: annexin V-FITC staining, mitochondrial membrane potential (MMP) depolarization measurements, the activity of caspases 3 and 7, nuclear DNA fragmentation, cell cycle analysis, modulation of Bax, Bcl-2, Smac/Diablo, Alox-5, VEGF-A, CXCR4, and CXCL12 mRNA gene expression via RT-PCR, 2D migration (scratch assay), and 3D invasion (Boyden chamber). MPc extract was the most active, inducing cell death (p < 0.05) via apoptosis, as evidenced by nuclear DNA fragmentation and an increase in MMP depolarization (p < 0.05) as well as the activation of caspases 3/7 (MPc p < 0.01) in both PC3 and LNCaP cell lines. In addition, MPc upregulated Bax and Smac/DIABLO, downregulated Bcl-2 (p < 0.05), and inhibited ALOX-5 mRNA gene expression (p < 0.001). MPc was not cytotoxic against normal human fibroblast cells (HDFa) at the tested concentrations. Moreover, MPc inhibited migration and invasion of PC3 cells (p < 0.01). These effects were accompanied by the downregulation of both VEGF-A and CXCL-12 gene expressions (p < 0.001). A monounsaturated 5-alkyl resorcinol was isolated as the active compound in the MPc extract and identified as 5-henicosene-1-yl-resorcinol.
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Affiliation(s)
- Mohd Mukrish Mohd Hanafi
- Department of Pharmaceutical and Biological Chemistry, U.C.L. School of Pharmacy, London WC1N 1AX, UK; (M.M.M.H.); (S.G.)
| | - Harisun Yaakob
- Institute of Bioproduct Development (IBD), Universiti Teknologi Malaysia, Johor Bahru 81310, Malaysia;
| | - Simon Gibbons
- Department of Pharmaceutical and Biological Chemistry, U.C.L. School of Pharmacy, London WC1N 1AX, UK; (M.M.M.H.); (S.G.)
- School of Pharmacy, University of East Anglia, Norwich NR4 7TJ, UK
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool L3 3AF, UK
| | - Jose M. Prieto
- Department of Pharmaceutical and Biological Chemistry, U.C.L. School of Pharmacy, London WC1N 1AX, UK; (M.M.M.H.); (S.G.)
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool L3 3AF, UK
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Stelmasiewicz M, Świątek Ł, Gibbons S, Ludwiczuk A. Bioactive Compounds Produced by Endophytic Microorganisms Associated with Bryophytes—The “Bryendophytes”. Molecules 2023; 28:molecules28073246. [PMID: 37050009 PMCID: PMC10096483 DOI: 10.3390/molecules28073246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 03/31/2023] [Accepted: 04/03/2023] [Indexed: 04/08/2023] Open
Abstract
The mutualistic coexistence between the host and endophyte is diverse and complex, including host growth regulation, the exchange of substances like nutrients or biostimulants, and protection from microbial or herbivore attack. The latter is commonly associated with the production by endophytes of bioactive natural products, which also possess multiple activities, including antibacterial, insecticidal, antioxidant, antitumor, and antidiabetic properties, making them interesting and valuable model substances for future development into drugs. The endophytes of higher plants have been extensively studied, but there is a dearth of information on the biodiversity of endophytic microorganisms associated with bryophytes and, more importantly, their bioactive metabolites. For the first time, we name bryophyte endophytes “bryendophytes” to elaborate on this important and productive source of biota. In this review, we summarize the current knowledge on the diversity of compounds produced by endophytes, emphasizing bioactive molecules from bryendophytes. Moreover, the isolation methods and biodiversity of bryendophytes from mosses, liverworts, and hornworts are described.
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Affiliation(s)
- Mateusz Stelmasiewicz
- Department of Pharmacognosy with the Medicinal Plant Garden, Medical University of Lublin, 20-093 Lublin, Poland
| | - Łukasz Świątek
- Department of Virology with Viral Diagnostics Laboratory, Medical University of Lublin, 20-093 Lublin, Poland
| | - Simon Gibbons
- Centre for Natural Products Discovery (CNPD), Liverpool John Moores University, Liverpool L3 3AF, UK
| | - Agnieszka Ludwiczuk
- Department of Pharmacognosy with the Medicinal Plant Garden, Medical University of Lublin, 20-093 Lublin, Poland
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de Resende PE, Soares S, Zloh M, Gibbons S, Stapleton P. LY2183240 regioisomers act as competitive and selective inhibitors of class C β-lactamases. Int J Antimicrob Agents 2023; 61:106774. [PMID: 36893812 DOI: 10.1016/j.ijantimicag.2023.106774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 02/21/2023] [Accepted: 03/01/2023] [Indexed: 03/09/2023]
Abstract
The regioisomers of the anandamide-acting drug LY2183240 exhibited specific potent and competitive inhibitory activities against class C β-lactamases. More explicitly, the 1,5- and 2,5-regioisomers inhibited AmpC from Enterobacter hormaechei (formerly Enterobacter cloacae) with Ki values of 1.8 µM and 2.45 µM, respectively. Structural molecular modelling studies revealed the interaction of the regioisomers with the relevant residues of the catalytic site of cephalosporinase from E. hormaechei P99, which included Tyr150, Lys315 and Thr316.
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Affiliation(s)
- Pedro Ernesto de Resende
- UCL School of Pharmacy, Research Department of Pharmaceutical and Biological Chemistry, University College London, 29-39 Brunswick Square, London, WC1N 1AX..
| | - Sarah Soares
- UCL School of Pharmacy, Research Department of Pharmaceutical and Biological Chemistry, University College London, 29-39 Brunswick Square, London, WC1N 1AX
| | - Mire Zloh
- UCL School of Pharmacy, Research Department of Pharmaceutical and Biological Chemistry, University College London, 29-39 Brunswick Square, London, WC1N 1AX
| | - Simon Gibbons
- UCL School of Pharmacy, Research Department of Pharmaceutical and Biological Chemistry, University College London, 29-39 Brunswick Square, London, WC1N 1AX.; Centre for Natural Products Discovery (CNPD), Liverpool John Moores University, Liverpool L3 3AF, England, UK
| | - Paul Stapleton
- UCL School of Pharmacy, Research Department of Pharmaceutical and Biological Chemistry, University College London, 29-39 Brunswick Square, London, WC1N 1AX
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AlQathama A, Bader A, Al-Rehaily A, Gibbons S, Prieto JM. In vitro cytotoxic activities of selected Saudi medicinal plants against human malignant melanoma cells (A375) and the isolation of their active principles. Eur J Integr Med 2022. [DOI: 10.1016/j.eujim.2021.102083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Xiao CY, Sun ZL, Huang J, Li RS, He JM, Gibbons S, Ju DW, Mu Q. Neolignans from Piper betle Have Synergistic Activity against Antibiotic-Resistant Staphylococcus aureus. J Org Chem 2021; 86:11072-11085. [PMID: 33439020 DOI: 10.1021/acs.joc.0c02682] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A phytochemical investigation of an extract of the leaves of Piper betle, guided by a synergistic antibacterial screen, led to the isolation and structural elucidation of 10 new neolignans, Pibeneolignan A-J (1-10), together with 11 known compounds. The structures and absolute configurations of the new compounds were elucidated on the basis of spectroscopic data, single-crystal X-ray diffraction analysis, and experimental and calculated ECD investigations. Compounds 1 and 2 are new naturally occurring neolignan skeletons, based on the cyclohept-2-ene-1,4-dione framework. We propose that these natural products are biosynthetically formed from bicyclic [3.2.1] neolignans by oxidative cleavage and ring opening at C-1' and C-2'. Among these compounds, 9, 13, 15, and 16, in combination with norfloxacin against an effluxing S. aureus strain (SA1199B), exhibited significant synergistic activity with fractional inhibitory concentration indices (FICIs) of 0.078, 0.156, 0.125, and 0.25, respectively. Bacterial growth curves, ethidium bromide (EtBr) efflux, and qRt-PCR were further employed to verify their synergistic antibacterial mechanism. Furthermore, computational molecular modeling suggested the binding of compounds 14-17 and 19 to the active site of the modeled structure of the NorA efflux pump, which is the main efflux pump in SA1199B.
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Affiliation(s)
- Chuan-Yun Xiao
- School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Zhong-Lin Sun
- School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Jiao Huang
- School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Rong-Sheng Li
- School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Jian-Ming He
- School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Simon Gibbons
- School of Pharmacy, University of East Anglia, Norwich NR4 7TJ, U.K
| | - Dian-Wen Ju
- School of Pharmacy, Fudan University, Shanghai 201203, China.,Shanghai Engineering Research Center of ImmunoTherapeutics, Shanghai 201203, China
| | - Qing Mu
- School of Pharmacy, Fudan University, Shanghai 201203, China
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13
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Balunas MJ, Cragg GM, Gibbons S, Mata R. Professor A. Douglas Kinghorn. A Lifetime Career Dedicated to Outstanding Service to Natural Product Sciences. J Nat Prod 2021; 84:549-552. [PMID: 33765769 DOI: 10.1021/acs.jnatprod.0c01371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Affiliation(s)
- Marcy J Balunas
- University of Connecticut, Storrs, Connecticut, United States
| | - Gordon M Cragg
- NIH Special Volunteer, Gaithersburg, Maryland, United States
| | - Simon Gibbons
- University of East Anglia, Norwich Research Park, Norwich, U.K
| | - Rachel Mata
- National Autonomous University of Mexico, Mexico City, Mexico
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Teo SP, Bhakta S, Stapleton P, Gibbons S. Bioactive Compounds from the Bornean Endemic Plant Goniothalamus longistipetes. Antibiotics (Basel) 2020; 9:antibiotics9120913. [PMID: 33339285 PMCID: PMC7767169 DOI: 10.3390/antibiotics9120913] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 12/08/2020] [Accepted: 12/15/2020] [Indexed: 11/24/2022] Open
Abstract
The present study aimed to screen plants for bioactive compounds with potential antibacterial activities. In our efforts to evaluate plants from Borneo, we isolated and elucidated the structures of four natural products from the bioactive fraction of a chloroform extract of Goniothalamus longistipetes using various chromatographic and spectroscopic techniques. The bioactive compounds were identified as a known styryllactone, (+)-altholactone ((2S,3R,3aS,7aS)-3-hydroxy-2-phenyl-2,3,3a,7a-tetrahydrobenzo-5(4H)-5-one) (1), a new styryllactone, (2S,3R,3aS,7aS)-3-hydroxy-2-phenyl-2,3,3a,7a-tetrahydrobenzo-5(4H)-5-one) (2) as well as a new alkaloid, 2,6-dimethoxyisonicotinaldehyde (3) and a new alkenyl-5-hydroxyl-phenyl benzoic acid (4). 1 and 4 showed broad-spectrum anti-bacterial activities against Gram-positive and Gram-negative bacteria as well as acid-fast model selected for this study. Compound 2 only demonstrated activities against Gram-positive bacteria whilst 3 displayed selective inhibitory activities against Gram-positive bacterial strains. Additionally, their mechanisms of anti-bacterial action were also investigated. Using Mycobacterium smegmatis as a fast-growing model of tubercle bacilli, compounds 1, 2 and 4 demonstrated inhibitory activities against whole-cell drug efflux and biofilm formation; two key intrinsic mechanisms of antibiotic resistance. Interestingly, the amphiphilic compound 4 exhibited inhibitory activity against the conjugation of plasmid pKM101 in Escherichia coli using a plate conjugation assay. Plasmid conjugation is a mechanism by which Gram-positive and Gram-negative-bacteria acquire drug resistance and virulence. These results indicated that bioactive compounds isolated from Goniothalamus longistipetes can be potential candidates as ‘hits’ for further optimisation.
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Affiliation(s)
- Stephen P. Teo
- Research Department of Pharmaceutical and Biological Chemistry, School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK; (P.S.); (S.G.)
- Department of Biological Sciences, Institute of Structural and Molecular Biology, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK;
- Forest Department Sarawak, Wisma Sumber Alam, Petra Jaya, Kuching 93600, Malaysia
- Correspondence:
| | - Sanjib Bhakta
- Department of Biological Sciences, Institute of Structural and Molecular Biology, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK;
| | - Paul Stapleton
- Research Department of Pharmaceutical and Biological Chemistry, School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK; (P.S.); (S.G.)
| | - Simon Gibbons
- Research Department of Pharmaceutical and Biological Chemistry, School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK; (P.S.); (S.G.)
- School of Pharmacy, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
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15
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AlQathama A, Shao L, Bader A, Khondkar P, Gibbons S, M Prieto J. Differential Anti-Proliferative and Anti-Migratory Activities of Ursolic Acid, 3- O-Acetylursolic Acid and Their Combination Treatments with Quercetin on Melanoma Cells. Biomolecules 2020; 10:E894. [PMID: 32545262 PMCID: PMC7356947 DOI: 10.3390/biom10060894] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Revised: 06/10/2020] [Accepted: 06/10/2020] [Indexed: 01/02/2023] Open
Abstract
We evaluate how 3-acetylation modulates the in vitro activity of ursolic acid in melanoma cells alone or in combination treatments with quercetin. Anti-proliferative studies on A375 cells and adult human dermal fibroblasts included analyses on cell cycle distribution, caspase activity, phosphatidylserine translocation, cell morphology and Bax/Bcl-2 protein expression. Then, 2D and 3D migration of B16F10 cells were studied using scratch and Transwell assays, respectively. Ursolic acid and 3-O-acetylursolic acid have shown similar GI50 on A375 cells (26 µM vs. 32 µM, respectively) significantly increased both early and late apoptotic populations, activated caspases 3/7 (48-72 h), and enhanced Bax whilst attenuating Bcl-2 expression. Ursolic acid caused elevation of the sub-G1 population whilst its 3-acetyl derivative arrested cell cycle at S phase and induced strong morphological changes. Combination treatments showed that ursolic acid and quercetin act synergistically in migration assays but not against cell proliferation. In summary, 3-O-acetylursolic acid maintains the potency and overall apoptotic mechanism of the parent molecule with a more aggressive influence on the morphology of A375 melanoma cells but the 3-acetylation suppresses its anti-migratory properties. We also found that ursolic acid can act in synergy with quercetin to reduce cell migration.
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Affiliation(s)
- Aljawharah AlQathama
- School of Pharmacy, University College London, London WC1N 1AX, UK; (L.S.); (P.K.); (S.G.)
- Department of Pharmacognosy, Pharmacy College, Umm Al-Qura University, Makkah 21955, Saudi Arabia;
| | - Luying Shao
- School of Pharmacy, University College London, London WC1N 1AX, UK; (L.S.); (P.K.); (S.G.)
| | - Ammar Bader
- Department of Pharmacognosy, Pharmacy College, Umm Al-Qura University, Makkah 21955, Saudi Arabia;
| | - Proma Khondkar
- School of Pharmacy, University College London, London WC1N 1AX, UK; (L.S.); (P.K.); (S.G.)
| | - Simon Gibbons
- School of Pharmacy, University College London, London WC1N 1AX, UK; (L.S.); (P.K.); (S.G.)
- School of Pharmacy, University East Anglia, Norwich NR4 7TJ, UK
| | - Jose M Prieto
- School of Pharmacy, University College London, London WC1N 1AX, UK; (L.S.); (P.K.); (S.G.)
- Centre for Natural Products Discovery, School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool L3 3AF, UK
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16
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Abstract
The isolation of two diarylnonanoids from Dioscorea cotinifolia possessing antibiotic-potentiating activity against resistant strains of S. aureus are reported. The diarylnonanoids are a class of natural products similar in structure to the diarylheptanoids, which have a wide spectrum of reported biological activities. One of the diarylnonanoids (1) isolated possesses a chiral center, and to deduce its configuration, the modified Mosher ester method was used. Using both 1D and 2D NMR data, as many protons as possible were assigned to both the R- and S-MTPA esters, and the configuration of the chiral center in 1 was determined to be R. Both the chiral and achiral diarylnonanoid (2) exhibited potent antibiotic-potentiating activity with the chiral natural product showing a greater tetracycline-potentiating activity than 2. Interestingly, 2 gave a higher norfloxacin-potentiating activity with a resultant higher efflux pump inhibitory activity. Manipulation of the structure of the diarylnonanoids through synthesis could lead to improved biological activity.
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Affiliation(s)
- Gugu F Sibandze
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, United Kingdom
- Eswatini Institute for Research in Traditional Medicine, Medicinal and Indigenous Food Plants, University of Eswatini, Private Bag 4, Kwaluseni M201, Eswatini
| | - Paul Stapleton
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, United Kingdom
| | - Simon Gibbons
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, United Kingdom
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17
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Xiao CY, Mu Q, Gibbons S. The Phytochemistry and Pharmacology of Hypericum. Progress in the Chemistry of Organic Natural Products 112 2020; 112:85-182. [DOI: 10.1007/978-3-030-52966-6_2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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18
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Oyedemi BO, Kotsia EM, Stapleton PD, Gibbons S. Capsaicin and gingerol analogues inhibit the growth of efflux-multidrug resistant bacteria and R-plasmids conjugal transfer. J Ethnopharmacol 2019; 245:111871. [PMID: 31022566 DOI: 10.1016/j.jep.2019.111871] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 04/06/2019] [Accepted: 04/07/2019] [Indexed: 06/09/2023]
Abstract
ETHNOPHARMACOLOGICAL IMPORTANCE Capsicum and ginger are used widely in human diets and in folklore medicines. Chemically, gingerol is a relative of capsaicin and both classes of compounds are notable for their spiciness and characteristic pungent aroma. Previous studies have demonstrated that these compounds contain antimicrobial compounds with robust pharmacological importance. AIM The present study evaluated the in vitro antibacterial activities of capsaicinoids and gingerols against a panel of clinical MRSA strains and their inhibitory effect on the conjugal transfer of R-plasmids harboured in E. coli. MATERIALS AND METHODS Crude methanol extract of C. annum was fractionated using solid phase extraction (SPE) and screened for R-plasmid transfer inhibition: TP114, PUB 307, PKM 101, R6K and R7K. The bio-guided assay led to the isolation of bioactive compounds with strong R-plasmid transfer inhibition. The compounds were identified using Nuclear Magnetic resonance (NMR) and Mass spectroscopy (MS). Capsaicin analogues nonivamide, 6-gingerol, 6-shogaol, capsaicin and dihydrocapsaicin were screened for antimicrobial activity against a panel of methicillin-resistant Staphylococcus aureus (MRSA) and Gram-negative bacteria strains using microdilution method while the plasmid transfer inhibition assay of the compounds was determined by broth mating method. RESULTS The bioactive fraction Ca-11 showed good inhibition rates (8.57-25.52%) against three R-plasmids PUB307, PKM 101, TP114 followed by the crude extract of C. annum (8.59%) respectively leading to the bioassay-guided isolation of capsaicin and dihydrocapsaicin as the bioactive principles. The antiplasmid effect of pure capsaicin and dihydrocapsaicin were broad and within active ranges (5.03-31.76%) against the various antibiotic resistance-conferring plasmids including R6K, R7K. Capsaicin, 6-gingerol and 6-shogaol had good broad antibacterial activity with MIC values ranging from 8 to 256 mg/L against effluxing MRSA strains SA1199B (NorA), XU212 (TetK) and RN4220 (MsrA). While they exhibited moderate antibacterial activity (128-512 mg/L) against the Gram-negative bacteria. The effect of 6-gingerol, 6-shogaol and nonivamide on the plasmids were very active on PKM 101 (6.24-22.16%), PUB 307 (1.22-45.63%) and TP114 (0.1-7.19%) comparative to the positive control plumbagin (5.70-31.76%). CONCLUSION These results are suggestive that the R-plasmids could possess substrate for capsaicinoids-like compounds and for their ability to inhibit the plasmid conjugation processes. Plant natural products possess the potential value of antibacterial and mechanistic antiplasmid activity as demonstrated by the compounds and should be evaluated in developing antimicrobial leads to novel mechanism against multidrug-resistant bacteria.
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Affiliation(s)
- Blessing Om Oyedemi
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, London, UK
| | - E M Kotsia
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, London, UK
| | - Paul D Stapleton
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, London, UK
| | - Simon Gibbons
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, London, UK.
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19
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Yeung AWK, Tzvetkov NT, Gupta VK, Gupta SC, Orive G, Bonn GK, Fiebich B, Bishayee A, Efferth T, Xiao J, Silva AS, Russo GL, Daglia M, Battino M, Orhan IE, Nicoletti F, Heinrich M, Aggarwal BB, Diederich M, Banach M, Weckwerth W, Bauer R, Perry G, Bayer EA, Huber LA, Wolfender JL, Verpoorte R, Macias FA, Wink M, Stadler M, Gibbons S, Cifuentes A, Ibanez E, Lizard G, Müller R, Ristow M, Atanasov AG. Current research in biotechnology: Exploring the biotech forefront. Current Research in Biotechnology 2019. [DOI: 10.1016/j.crbiot.2019.08.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
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20
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Lan JE, Li XJ, Zhu XF, Sun ZL, He JM, Zloh M, Gibbons S, Mu Q. Flavonoids from Artemisia rupestris and their synergistic antibacterial effects on drug-resistant Staphylococcus aureus. Nat Prod Res 2019; 35:1881-1886. [PMID: 31303068 DOI: 10.1080/14786419.2019.1639182] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
This study seeks to discover flavonoids from a traditional Chinese herb, Artemisia rupestris L., with synergistic antibacterial effects against multidrug-resistant Staphylococcus aureus. Five flavonoids, artemetin (1), chrysosplenetin (2), pachypodol (3), penduletin (4) and chrysoeriol (5) were obtained by various column chromatographic methods. Their chemical structures were determined on the basis of comprehensive spectroscopic analysis and comparison with literature data. Three of the compounds (2, 4 and 5) exhibited synergistic activity when combined with norfloxacin against SA1199B, an effluxing fluoroquinolone-resistant strain. The fractional inhibitory concentration indices (FICIs) of 2, 4 and 5 in combination with norfloxacin were 0.375, 0.079 and 0.266 respectively, suggesting synergy. Compound 5 also showed synergistic effects against EMRSA-15 and EMRSA-16 when combined with ciprofloxacin and oxacillin exhibiting FICIs of 0.024 and 0.375 respectively. Real time ethidium bromide (EtBr) efflux assay, qRT-PCR and molecular docking were employed to explore the mechanisms of the synergistic effects.
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Affiliation(s)
- Jiang-Er Lan
- School of Pharmacy, Fudan University, Shanghai, 201203, China
| | - Xiao-Jin Li
- Traditional Chinese Medicine and Ethno Medicine Institute of Xinjiang, Wulumuqi, 800002, China
| | - Xiao-Feng Zhu
- School of Pharmacy, Fudan University, Shanghai, 201203, China
| | - Zhong-Lin Sun
- School of Pharmacy, Fudan University, Shanghai, 201203, China
| | - Jian-Ming He
- School of Pharmacy, Fudan University, Shanghai, 201203, China
| | - Mire Zloh
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, London, WC1N 1AX, United Kingdom
| | - Simon Gibbons
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, London, WC1N 1AX, United Kingdom
| | - Qing Mu
- School of Pharmacy, Fudan University, Shanghai, 201203, China
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21
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Gibbons S, Fleming A, Fairhurst A, Ford C, Barth J. Clinical and analytical evaluation of LC-MS methods for plasma renin activity and aldosterone. Clin Chim Acta 2019. [DOI: 10.1016/j.cca.2019.03.744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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22
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Walker T, Stapleton P, Gibbons S. Identification of novel antimicrobial-producing bacteria from an ancient water source by Oxford Nanopore Whole Genome Sequencing and Natural Product Chemistry. Access Microbiol 2019. [DOI: 10.1099/acmi.ac2019.po0214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Tim Walker
- University College London, London, United Kingdom
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23
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Kwapong AA, Stapleton P, Gibbons S. Inhibiting plasmid mobility: The effect of isothiocyanates on bacterial conjugation. Int J Antimicrob Agents 2019; 53:629-636. [PMID: 30685311 DOI: 10.1016/j.ijantimicag.2019.01.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 12/12/2018] [Accepted: 01/20/2019] [Indexed: 01/13/2023]
Abstract
Bacterial conjugation is the main mechanism for the transfer of multiple antimicrobial resistance genes among pathogenic micro-organisms. This process may be controlled by compounds that inhibit bacterial conjugation. In this study, the effects of allyl isothiocyanate, l-sulforaphane, benzyl isothiocyanate, phenylethyl isothiocyanate and 4-methoxyphenyl isothiocyanate on the conjugation of broad-host-range plasmids harbouring various antimicrobial resistance genes in Escherichia coli were investigated, namely plasmids pKM101 (IncN), TP114 (IncI2), pUB307 (IncP) and the low-copy-number plasmid R7K (IncW). Benzyl isothiocyanate (32 mg/L) significantly reduced conjugal transfer of pKM101, TP114 and pUB307 to 0.3 ± 0.6%, 10.7 ± 3.3% and 6.5 ± 1.0%, respectively. l-sulforaphane (16 mg/L; transfer frequency 21.5 ± 5.1%) and 4-methoxyphenyl isothiocyanate (100 mg/L; transfer frequency 5.2 ± 2.8%) were the only compounds showing anti-conjugal specificity by actively reducing the transfer of R7K and pUB307, respectively.
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Affiliation(s)
- Awo Afi Kwapong
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK; Department of Pharmaceutics and Microbiology, School of Pharmacy, University of Ghana, Accra, Ghana
| | - Paul Stapleton
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK
| | - Simon Gibbons
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK.
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24
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Rakovitsky N, Bar Oz M, Goldberg K, Gibbons S, Zimhony O, Barkan D. The Unexpected Essentiality of glnA2 in Mycobacterium smegmatis Is Salvaged by Overexpression of the Global Nitrogen Regulator glnR, but Not by L-, D- or Iso-Glutamine. Front Microbiol 2018; 9:2143. [PMID: 30271391 PMCID: PMC6142876 DOI: 10.3389/fmicb.2018.02143] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 08/21/2018] [Indexed: 01/14/2023] Open
Abstract
Nitrogen metabolism plays a central role in the physiology of microorganisms, and Glutamine Synthetase (GS) genes are present in virtually all bacteria. In M. tuberculosis, four GS genes are present, but only glnA1 is essential, whereas glnA2 was shown to be non-essential for in-vitro as well as in-vivo growth and pathogenesis, and is postulated to be involved in D-glutamine and iso-glutamine synthesis. Whilst investigating the activity of an antimicrobial compound in M. smegmatis, we found a spontaneous temperature-sensitive mutant in glnA2 (I133F), and used it to investigate the role of glnA2 in M. smegmatis. We deleted the native glnA2 and replaced it with a mutated allele. This re-created the temperature sensitivity—as after 3–4 seemingly normal division cycles, glnA2 became essential for growth. This essentiality could not be salvaged by neither L, D- nor iso-glutamine, suggesting an additional role of glnA2 in M. smegmatis over its role in M. tuberculosis. We also found that overexpression of the global nitrogen regulator glnR enabled bypassing the essentiality of glnA2, allowing the creation of a complete deletion mutant. The discrepancy between the importance of glnA2 in Mtb and M. smegmatis stresses the caution in which results in one are extrapolated to the other.
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Affiliation(s)
- Nadya Rakovitsky
- Koret School of Veterinary Medicine, The Robert H. Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Michal Bar Oz
- Koret School of Veterinary Medicine, The Robert H. Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Karin Goldberg
- Department of Pharmaceutical Engineering, Azrieli College of Engineering, Jerusalem, Israel
| | - Simon Gibbons
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, London, United Kingdom
| | - Oren Zimhony
- Kaplan Medical Center, Rehovot, Israel.,The Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Daniel Barkan
- Koret School of Veterinary Medicine, The Robert H. Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Jerusalem, Israel
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25
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Moorthie S, Blencowe H, Darlison MW, Lawn J, Morris JK, Modell B, Bittles AH, Blencowe H, Christianson A, Cousens S, Darlison MW, Gibbons S, Hamamy H, Khoshnood B, Howson CP, Lawn J, Mastroiacovo P, Modell B, Moorthie S, Morris JK, Mossey PA, Neville AJ, Petrou M, Povey S, Rankin J, Schuler-Faccini L, Wren C, Yunnis KA. Estimating the birth prevalence and pregnancy outcomes of congenital malformations worldwide. J Community Genet 2018; 9:387-396. [PMID: 30218347 PMCID: PMC6167261 DOI: 10.1007/s12687-018-0384-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 08/29/2018] [Indexed: 12/22/2022] Open
Abstract
Congenital anomaly registries have two main surveillance aims: firstly to define baseline epidemiology of important congenital anomalies to facilitate programme, policy and resource planning, and secondly to identify clusters of cases and any other epidemiological changes that could give early warning of environmental or infectious hazards. However, setting up a sustainable registry and surveillance system is resource-intensive requiring national infrastructure for recording all cases and diagnostic facilities to identify those malformations that that are not externally visible. Consequently, not all countries have yet established robust surveillance systems. For these countries, methods are needed to generate estimates of prevalence of these disorders which can act as a starting point for assessing disease burden and service implications. Here, we describe how registry data from high-income settings can be used for generating reference rates that can be used as provisional estimates for countries with little or no observational data on non-syndromic congenital malformations.
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Affiliation(s)
| | - Hannah Blencowe
- Centre for Maternal, Adolescent, Reproductive, and Child Health, London School of Hygiene and Tropical Medicine, London, UK
| | - Matthew W Darlison
- Centre for Health Informatics and Multiprofessional Education (CHIME), University College London, London, UK.
| | - Joy Lawn
- Centre for Maternal, Adolescent, Reproductive, and Child Health, London School of Hygiene and Tropical Medicine, London, UK
| | - Joan K Morris
- Centre for Environmental and Preventive Medicine, Wolfson Institute of Preventive Medicine, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Bernadette Modell
- Centre for Health Informatics and Multiprofessional Education (CHIME), University College London, London, UK
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26
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Skalicka-Woźniak K, Walasek M, Aljarba TM, Stapleton P, Gibbons S, Xiao J, Łuszczki JJ. The anticonvulsant and anti-plasmid conjugation potential of Thymus vulgaris chemistry: An in vivo murine and in vitro study. Food Chem Toxicol 2018; 120:472-478. [PMID: 30055314 DOI: 10.1016/j.fct.2018.07.045] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 06/28/2018] [Accepted: 07/24/2018] [Indexed: 02/08/2023]
Abstract
The high-performance counter-current chromatography was used for the efficient purification of single constituents from Thymus vulgaris essential oil. Mixtures of n-heptane, ethyl acetate, methanol, and water (5:2:5:2 and 4:1:4:1 v/v), allowed purification of eugenol, 1-octen-3- ol, borneol, thymol, terpinen-4-ol, and camphor, while n-hexane, acetonitrile, and tert-butyl methyl ether (1:1:0.1 v/v) yielded carvacrol, borneol, linalyl acetate, caryophyllene oxide, p-cymene, and eucalyptol. The anticonvulsant activities were evaluated in the maximal electroshock-induced seizure test in mice model (systemic i. p. administration). The oil exerted protection against MES-induced seizures when administered 15 and 30 min before the tests (50 and 62.5%, respectively). Among the isolates, borneol, thymol, and eugenol exerted the strongest protection against seizures. Moreover, linalool had the ability to reduce the transfer of the pKM101 plasmid by 84%, what has the potential to reduce virulence and resistance spread in E. coli. No acute toxic effects towards the CNS were noticed either for the essential oil or for single compounds, in the chimney and grip-strength tests. The preclinical screening of Thymus vulgaris EO, as well as isolated terpenoids, provides evidence that the EO has partial protective activity against seizures and HPCCC technique is suitable for its large scale isolation.
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Affiliation(s)
- Krystyna Skalicka-Woźniak
- Department of Pharmacognosy with Medicinal Plant Unit, Medical University of Lublin, Chodzki 1, PL 20-093, Lublin, Poland.
| | - Magdalena Walasek
- Department of Pharmacognosy with Medicinal Plant Unit, Medical University of Lublin, Chodzki 1, PL 20-093, Lublin, Poland
| | - Tariq M Aljarba
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, London, WC1N 1AX, UK
| | - Paul Stapleton
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, London, WC1N 1AX, UK
| | - Simon Gibbons
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, London, WC1N 1AX, UK
| | - Jianbo Xiao
- Institute of Chinese Medical Sciences, University of Macau, Taipa, Macau
| | - Jarogniew J Łuszczki
- Department of Pathophysiology, Medical University of Lublin, Jaczewskiego 8b, PL 20-090, Lublin, Poland; Isobolographic Analysis Laboratory, Institute of Rural Health, Jaczewskiego 2, PL 20-950, Lublin, Poland
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27
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Rahman MM, Shiu WKP, Gibbons S, Malkinson JP. Total synthesis of acylphloroglucinols and their antibacterial activities against clinical isolates of multi-drug resistant (MDR) and methicillin-resistant strains of Staphylococcus aureus. Eur J Med Chem 2018; 155:255-262. [PMID: 29890387 DOI: 10.1016/j.ejmech.2018.05.038] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 05/22/2018] [Accepted: 05/24/2018] [Indexed: 10/16/2022]
Abstract
Bioassay-directed drug discovery efforts focusing on various species of the genus Hypericum led to the discovery of a number of new acylphloroglucinols including (S,E)-1-(2-((3,7-dimethylocta-2,6-dien-1-yl)oxy)-4,6-dihydroxyphenyl)-2-methylbutan-1-one (6, olympicin A) from H. olympicum, with MICs ranging from 0.5 to 1 mg/L against a series of clinical isolates of multi-drug-resistant (MDR) and methicillin-resistant Staphylococcus aureus (MRSA) strains. The promising activity and interesting chemistry of olympicin A prompted us to carry out the total synthesis of 6 and a series of analogues in order to assess their structure-activity profile as a new group of antibacterial agents. Following the synthesis of 6 and structurally-related acylphloroglucinols 7-15 and 18-24, their antibacterial activities against a panel of S. aureus strains were evaluated. The presence of an alkyloxy group consisting of 8-10 carbon atoms ortho to a five-carbon acyl substituent on the phloroglucinol core are important structural features for promising anti-staphylococcal activity.
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Affiliation(s)
- M Mukhlesur Rahman
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK; Medicine Research Group, School of Health, Sport and Bioscience, University of East London, Stratford Campus, Water Lane, London, E15 4LZ, UK
| | - Winnie K P Shiu
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK
| | - Simon Gibbons
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK
| | - John P Malkinson
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK.
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Gulsoy-Toplan G, Goger F, Yildiz-Pekoz A, Gibbons S, Sariyar G, Mat A. Chemical Constituents of the Different Parts of Colchicum micranthum and C. chalcedonicum and their Cytotoxic Activities. Nat Prod Commun 2018. [DOI: 10.1177/1934578x1801300506] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Colchicum species, which have been widely used as a medication for years, still remain important in treatment of Familial Mediterranean Fever, gout and Behcet's Disease. In the present work, alkaloids, phenolic compounds and cytotoxic activities from different parts of two Colchicum species, namely C. chalcedonicum and C. micranthum were investigated for the first time. From different parts of two species, alkaloids were isolated and colchicine concentrations were also determined by HPLC. The methanol extracts were investigated for their cytotoxic activity against the A549 cell line using the MTT and LDH methods. Additionally, the phenolic compounds of each extract were investigated by LC–MS/MS. Six alkaloids, namely colchicine, colchifoline, 2-demethylcolchicine, demecolcine, 4-hydroxycolchicine and N-deacetyl- N-formylcolchicine were isolated from different parts of two species. The autumn corm of C. micranthum possessed the highest amount of colchicine among all extracts. All extracts showed high cytotoxicity, while the highest toxicity was determined in the seed extract. According to the LC–MS/MS analysis, 19 phenolic compounds were shown to be present. This is the first study which highlights that the seeds of C. chalcedonicum and autumn corms of C. micranthum could be valuable for the pharmaceutical industry to obtain colchicine and other tropolone alkaloids.
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Affiliation(s)
- Gizem Gulsoy-Toplan
- Department of Pharmacognosy, Faculty of Pharmacy, Istanbul University, Istanbul, Turkey
| | - Fatih Goger
- Department of Pharmacognosy, Faculty of Pharmacy, Anadolu University, Eskisehir, Turkey
| | - Ayca Yildiz-Pekoz
- Department of Pharmaceutic Technology, Faculty of Pharmacy, Istanbul University, Istanbul, Turkey
| | - Simon Gibbons
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, London, UK
| | - Gunay Sariyar
- Faculty of Pharmacy, Cyprus International University, Lefkosa, Turkish Republic of Northern Cyprus
| | - Afife Mat
- Department of Pharmacognosy, Faculty of Pharmacy, Istanbul University, Istanbul, Turkey
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Roth BL, Gibbons S, Arunotayanun W, Huang XP, Setola V, Treble R, Iversen L. Correction: The Ketamine Analogue Methoxetamine and 3- and 4-Methoxy Analogues of Phencyclidine Are High Affinity and Selective Ligands for the Glutamate NMDA Receptor. PLoS One 2018; 13:e0194984. [PMID: 29566092 PMCID: PMC5864080 DOI: 10.1371/journal.pone.0194984] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Danquah CA, Kakagianni E, Khondkar P, Maitra A, Rahman M, Evangelopoulos D, McHugh TD, Stapleton P, Malkinson J, Bhakta S, Gibbons S. Analogues of Disulfides from Allium stipitatum Demonstrate Potent Anti-tubercular Activities through Drug Efflux Pump and Biofilm Inhibition. Sci Rep 2018; 8:1150. [PMID: 29348586 PMCID: PMC5773482 DOI: 10.1038/s41598-017-18948-w] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 12/19/2017] [Indexed: 11/24/2022] Open
Abstract
Disulfides from Allium stipitatum, commonly known as Persian shallot, were previously reported to possess antibacterial properties. Analogues of these compounds, produced by S-methylthiolation of appropriate thiols using S-methyl methanethiosulfonate, exhibited antimicrobial activity, with one compound inhibiting the growth of Mycobacterium tuberculosis at 17 µM (4 mg L-1) and other compounds inhibiting Escherichia coli and multi-drug-resistant (MDR) Staphylococcus aureus at concentrations ranging between 32-138 µM (8-32 mg L-1). These compounds also displayed moderate inhibitory effects on Klebsiella and Proteus species. Whole-cell phenotypic bioassays such as the spot-culture growth inhibition assay (SPOTi), drug efflux inhibition, biofilm inhibition and cytotoxicity assays were used to evaluate these compounds. Of particular note was their ability to inhibit mycobacterial drug efflux and biofilm formation, while maintaining a high selectivity towards M. tuberculosis H37Rv. These results suggest that methyl disulfides are novel scaffolds which could lead to the development of new drugs against tuberculosis (TB).
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Affiliation(s)
- Cynthia A Danquah
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK
- Department of Biological Sciences, Institute of Structural and Molecular Biology, Birkbeck, University of London, Malet Street, London, WC1E 7HX, UK
| | - Eleftheria Kakagianni
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK
| | - Proma Khondkar
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK
- Department of Pharmaceutical, Chemical and Environmental Sciences, University of Greenwich, Central Avenue, Chatham Maritime, ME4 4TB, UK
| | - Arundhati Maitra
- Department of Biological Sciences, Institute of Structural and Molecular Biology, Birkbeck, University of London, Malet Street, London, WC1E 7HX, UK
| | - Mukhlesur Rahman
- Medicine Research Group, School of Health, Sport and Bioscience, University of East London, Water Lane, London, E15 4LZ, UK
| | | | - Timothy D McHugh
- Centre for Clinical Microbiology, UCL Royal Free Hospital, Rowland Hill, London, NW3 2PF, UK
| | - Paul Stapleton
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK
| | - John Malkinson
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK
| | - Sanjib Bhakta
- Department of Biological Sciences, Institute of Structural and Molecular Biology, Birkbeck, University of London, Malet Street, London, WC1E 7HX, UK.
| | - Simon Gibbons
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK.
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Cvijetić IN, Verbić TŽ, Ernesto de Resende P, Stapleton P, Gibbons S, Juranić IO, Drakulić BJ, Zloh M. Design, synthesis and biological evaluation of novel aryldiketo acids with enhanced antibacterial activity against multidrug resistant bacterial strains. Eur J Med Chem 2017; 143:1474-1488. [PMID: 29133041 DOI: 10.1016/j.ejmech.2017.10.045] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 10/04/2017] [Accepted: 10/15/2017] [Indexed: 01/05/2023]
Abstract
Antimicrobial resistance (AMR) is a major health problem worldwide, because of ability of bacteria, fungi and viruses to evade known therapeutic agents used in treatment of infections. Aryldiketo acids (ADK) have shown antimicrobial activity against several resistant strains including Gram-positive Staphylococcus aureus bacteria. Our previous studies revealed that ADK analogues having bulky alkyl group in ortho position on a phenyl ring have up to ten times better activity than norfloxacin against the same strains. Rational modifications of analogues by introduction of hydrophobic substituents on the aromatic ring has led to more than tenfold increase in antibacterial activity against multidrug resistant Gram positive strains. To elucidate a potential mechanism of action for this potentially novel class of antimicrobials, several bacterial enzymes were identified as putative targets according to literature data and pharmacophoric similarity searches for potent ADK analogues. Among the seven bacterial targets chosen, the strongest favorable binding interactions were observed between most active analogue and S. aureus dehydrosqualene synthase and DNA gyrase. Furthermore, the docking results in combination with literature data suggest that these novel molecules could also target several other bacterial enzymes, including prenyl-transferases and methionine aminopeptidase. These results and our statistically significant 3D QSAR model could be used to guide the further design of more potent derivatives as well as in virtual screening for novel antibacterial agents.
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Affiliation(s)
- Ilija N Cvijetić
- Innovation Center of the Faculty of Chemistry, University of Belgrade, Studentski trg 16, Belgrade, Serbia.
| | - Tatjana Ž Verbić
- Faculty of Chemistry, University of Belgrade, Studentski trg 16, Belgrade, Serbia
| | | | - Paul Stapleton
- UCL School of Pharmacy, University College London, London, UK
| | - Simon Gibbons
- UCL School of Pharmacy, University College London, London, UK
| | - Ivan O Juranić
- Institute of Chemistry, Technology and Metallurgy, Department of Chemistry, University of Belgrade, Njegoševa 12, Belgrade, Serbia
| | - Branko J Drakulić
- Institute of Chemistry, Technology and Metallurgy, Department of Chemistry, University of Belgrade, Njegoševa 12, Belgrade, Serbia
| | - Mire Zloh
- University of Hertfordshire, College Lane, Hatfield, AL10 9AB, UK.
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Al-Qathama A, Gibbons S, Prieto JM. Differential modulation of Bax/Bcl-2 ratio and onset of caspase-3/7 activation induced by derivatives of Justicidin B in human melanoma cells A375. Oncotarget 2017; 8:95999-96012. [PMID: 29221182 PMCID: PMC5707076 DOI: 10.18632/oncotarget.21625] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 08/26/2017] [Indexed: 12/26/2022] Open
Abstract
Diphyllin and its derivatives are well known cytotoxic natural products structurally related to the anti-cancer drug podophyllotoxin. We here study their structure-activity relationship upon human melanoma cells for first time. To this end, human melanoma A375 cells were incubated with Justicidin B and its 4-methoxylated or 4-glycosylated derivatives to evaluate their selective cytotoxicity and study their effects on cell cycle distribution, caspase activation, apoptosis induction using Annexin V-FITC/PI staining, cell morphology and western blot analysis. Diphyllin methyl ether (GI50 = 3.66 μM) and Justicidin B (GI50 = 1.70 μM) caused an elevation of both early and late apoptosis populations whereas Diphyllin apioside (GI50 = 0.84 μM) and its acetate (GI50= 0.39 μM) enhanced late apoptosis population only (Annexin V-positive/PI-positive). All induced cell cycle arrest at S phase and classic morphological indicators of apoptosis (blebbing, apoptotic bodies, and nuclear fragmentation) accompanied with an elevation of cells with low DNA content (sub-G1). All compounds increased the Bax/Bcl-2 ratio by enhancing Bax expression which evidences the involvement of the mitochondria (intrinsic pathway) in the apoptotic process. These caspase-3/7 results evidence that 4-methoxylation or 4-O-glycosylation of Justicidin B -a caspase independent mitochondrial apoptosis-inducer- triggers caspase-3/7 activation at different times (24h vs. 48h, respectively). Interestingly, the methoxylation causes attenuation of Bcl-2 protein expression contrarily to Diphyllin methyl ether or the O-glycosylated derivatives. Finally, the compounds exhibited significantly less toxicity when tested in adult human dermal fibroblasts and their GI50 in melanoma Sk-Mel-5 cells was not influenced by MDR1/Pgp inhibitors. This study may inform the synthesis of future Diphyllin derivatives with different apoptosis mechanism of action towards human melanoma cells.
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Affiliation(s)
- Aljawharah Al-Qathama
- Centre for Pharmacognosy and Phytotherapy, University College London School of Pharmacy, London WC1N 1AX, United Kingdom.,Department of Pharmacognosy, Faculty of Pharmacy, Umm Al-Qura University, Makkah 21955, Saudi Arabia
| | - Simon Gibbons
- Centre for Pharmacognosy and Phytotherapy, University College London School of Pharmacy, London WC1N 1AX, United Kingdom
| | - Jose M Prieto
- Centre for Pharmacognosy and Phytotherapy, University College London School of Pharmacy, London WC1N 1AX, United Kingdom
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Beharry S, Gibbons S. An overview of emerging and new psychoactive substances in the United Kingdom. Forensic Sci Int 2016; 267:25-34. [DOI: 10.1016/j.forsciint.2016.08.013] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 08/01/2016] [Accepted: 08/04/2016] [Indexed: 01/02/2023]
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Sharifi-Rad M, Iriti M, Sharifi-Rad M, Gibbons S, Sharifi-Rad J. Anti-methicillin-resistant Staphylococcus aureus (MRSA) activity of Rubiaceae, Fabaceae and Poaceae plants: A search for new sources of useful alternative antibacterials against MRSA infections. Cell Mol Biol (Noisy-le-grand) 2016; 62:39-45. [PMID: 27585260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Accepted: 08/14/2016] [Indexed: 06/06/2023]
Abstract
In this study, we evaluated the effects of the extracts of the leaves of species from the Rubiaceae (Galium aparine L. and Asperula arvensis L.), Fabaceae (Lathyrus aphaca L. and Vicia narbonensis L.) and Poaceae (Digitaria sanguinalis (L.) Scop. and Hordeum murinum L.) plant families on a wide and extensive panel of isolated methicillin-resistant Staphylococcus aureus strains (MRSA). The effects of the methanolic leaf extracts of Rubiaceae, Fabaceae and Poaceae plants on MRSA were evaluated by the disc diffusion assay and the broth dilution method. Among a total of 177 S. aureus isolates, 92 (51.97%) were found to be methicillin-resistant in an antibiogram and this was confirmed by the presence of the mecA gene in polymerase chain reaction method. All MRSA isolates were sensitive to all extracts. There were dose-dependent inhibitions on tested microorganisms for all plant extracts which showed maximum inhibition zones at a concentration of 300 mg/L. L. aphaca, G. aparine and H. murinum exhibited the highest antibacterial activity on the MRSA strains compared to the positive control (P < 0.05), as well as higher total polyphenol and flavonoid contents than other plant extracts. Minimum inhibitory concentrations on MRSA isolates ranged from 388.4 ± 0.2 mg/L, in D. sanguinalis, to 5.5 ± 0.1 mg/L, in L. aphaca. The methanolic extracts of L. aphaca (Fabaceae), G. aparine (Rubiaceae), and H. murinum (Poaceae) proved to have high antibacterial activity on MRSA isolates, thus representing promising antimicrobial agents in clinical settings.
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Affiliation(s)
| | - M Iriti
- Milan State University Department of Agricultural and Environmental Sciences Milan Italy
| | - M Sharifi-Rad
- University of Zabol Department of Range and Watershed Management, Faculty of Natural Resources Zabol Iran
| | - S Gibbons
- UCL School of Pharmacy Research Department of Pharmaceutical and Biological Chemistry London UK
| | - J Sharifi-Rad
- Zabol University of Medical Sciences Zabol Medicinal Plants Research Center Zabol Iran
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Affiliation(s)
- Simon Gibbons
- Department of Pharmaceutical and Biological Chemistry UCL School of Pharmacy London WC1N 1AX UK
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Affiliation(s)
- Simon Gibbons
- Research Department of Pharmaceutical and Biological Chemistry UCL School of Pharmacy London WC1N 1AX UK
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Coqueiro A, Choi YH, Verpoorte R, Gupta KBSS, De Mieri M, Hamburger M, Young MCM, Stapleton P, Gibbons S, Bolzani VDS. Antistaphylococcal Prenylated Acylphoroglucinol and Xanthones from Kielmeyera variabilis. J Nat Prod 2016; 79:470-6. [PMID: 26900954 DOI: 10.1021/acs.jnatprod.5b00858] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Bioactivity-guided fractionation of the EtOH extract of the branches of Kielmeyera variabilis led to the isolation of a new acylphoroglucinol (1), which was active against all the MRSA strains tested herein, with pronounced activity against strain EMRSA-16. Compound 1 displayed an MIC of 0.5 mg/L as compared with an MIC of 128 mg/L for the control antibiotic norfloxacin. The structure of the new compound was elucidated by 1D and 2D NMR spectroscopic analysis and mass spectrometry, and experimental and calculated ECD were used to determine the absolute configurations. The compounds β-sitosterol (2), stigmasterol (3), ergost-5-en-3-ol (4), and osajaxanthone (5) also occurred in the n-hexane fraction. The EtOAc fraction contained nine known xanthones: 3,6-dihydroxy-1,4,8-trimethoxyxanthone (6), 3,5-dihydroxy-4-methoxyxanthone (7), 3,4-dihydroxy-6,8-dimethoxyxanthone (8), 3,4-dihydroxy-2-methoxyxanthone (9), 5-hydroxy-1,3-dimethoxyxanthone (10), 4-hydroxy-2,3-dimethoxyxanthone (11), kielcorin (12), 3-hydroxy-2-methoxyxanthone (13), and 2-hydroxy-1-methoxyxanthone (14), which showed moderate to low activity against the tested MRSA strains.
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Affiliation(s)
- Aline Coqueiro
- Natural Products Laboratory, Institute of Biology, Leiden University , Sylviusweg 72, Leiden, 2333 BE, The Netherlands
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy , 29-39 Brunswick Square, London, WC1N 1AX, United Kingdom
- Department of Organic Chemistry, Institute of Chemistry, São Paulo State University , Prof. Francisco Degni 55, Araraquara, 14800-900, Brazil
| | - Young H Choi
- Natural Products Laboratory, Institute of Biology, Leiden University , Sylviusweg 72, Leiden, 2333 BE, The Netherlands
| | - Robert Verpoorte
- Natural Products Laboratory, Institute of Biology, Leiden University , Sylviusweg 72, Leiden, 2333 BE, The Netherlands
| | - Karthick B S S Gupta
- NMR Facility, Leiden Institute of Chemistry, Leiden University , Einsteinweg 55, Leiden, 2333 CC, The Netherlands
| | - Maria De Mieri
- Division of Pharmaceutical Biology, University of Basel , Klingelbergstrasse 50, Basel, CH-4056, Switzerland
| | - Matthias Hamburger
- Division of Pharmaceutical Biology, University of Basel , Klingelbergstrasse 50, Basel, CH-4056, Switzerland
| | - Maria C M Young
- Section of Plant Physiology and Biochemistry, Institute of Botany , São Paulo, 01061-970, Brazil
| | - Paul Stapleton
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy , 29-39 Brunswick Square, London, WC1N 1AX, United Kingdom
| | - Simon Gibbons
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy , 29-39 Brunswick Square, London, WC1N 1AX, United Kingdom
| | - Vanderlan da S Bolzani
- Department of Organic Chemistry, Institute of Chemistry, São Paulo State University , Prof. Francisco Degni 55, Araraquara, 14800-900, Brazil
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Danquah CA, Maitra A, Gibbons S, Faull J, Bhakta S. HT-SPOTi: A Rapid Drug Susceptibility Test (DST) to Evaluate Antibiotic Resistance Profiles and Novel Chemicals for Anti-Infective Drug Discovery. ACTA ACUST UNITED AC 2016; 40:17.8.1-17.8.12. [PMID: 26855282 DOI: 10.1002/9780471729259.mc1708s40] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Antibiotic resistance is one of the major threats to global health and well-being. The past decade has seen an alarming rise in the evolution and spread of drug-resistant strains of pathogenic microbes. The emergence of extensively drug resistant (XDR) strains of Mycobacterium tuberculosis and antimicrobial resistance among the ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa, and Enterobacter species) as well as fungal pathogens (such as certain species of Candida, Aspergillus, Cryptococcus, and Trichophyton) poses a significant 21st century scientific challenge. With an extremely limited arsenal of efficacious antibiotics, techniques that can (a) identify novel antimicrobials and (b) detect antimicrobial resistance are becoming increasingly important. In this article, we illustrate the HT-SPOTi, an assay that is principally based on the growth of an organism on agar medium containing a range of different concentrations of drugs or inhibitors. The simple methodology makes this assay ideal for evaluating novel antimicrobial compounds as well as profiling an organism's antibiotic resistance profile.
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Affiliation(s)
- Cynthia A Danquah
- Department of Biological Sciences, Institute of Structural and Molecular Biology, Birkbeck, University of London, London, United Kingdom.,Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, London, United Kingdom.,These authors contributed equally
| | - Arundhati Maitra
- Department of Biological Sciences, Institute of Structural and Molecular Biology, Birkbeck, University of London, London, United Kingdom.,These authors contributed equally
| | - Simon Gibbons
- Research Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, London, United Kingdom
| | - Jane Faull
- Department of Biological Sciences, Institute of Structural and Molecular Biology, Birkbeck, University of London, London, United Kingdom
| | - Sanjib Bhakta
- Department of Biological Sciences, Institute of Structural and Molecular Biology, Birkbeck, University of London, London, United Kingdom
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Sun ZL, He JM, Wang SY, Ma R, Khondkar P, Kaatz GW, Gibbons S, Mu Q. Benzocyclohexane oxide derivatives and neolignans from Piper betle inhibit efflux-related resistance in Staphylococcus aureus. RSC Adv 2016. [DOI: 10.1039/c6ra10199b] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Six active compounds were isolated fromPiper betleunder the guide of synergistic effects combined with antibiotic norfloxacin. The synergistic mechanism was explored and significant inhibition effects for EtBr efflux in SA1199B were found.
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Affiliation(s)
- Zhong-Lin Sun
- School of Pharmacy
- Fudan University
- Shanghai 201203
- China
| | - Jian-Ming He
- School of Pharmacy
- Fudan University
- Shanghai 201203
- China
| | | | - Ru Ma
- School of Pharmacy
- Fudan University
- Shanghai 201203
- China
| | - Proma Khondkar
- Research Department of Pharmaceutical and Biological Chemistry
- UCL School of Pharmacy
- London WC1N 1AX
- UK
| | - Glenn W. Kaatz
- The John D. Dingell Department of Veteran's Affairs Medical Centre and Department of Internal Medicine
- Division of Infectious Diseases
- School of Medicine
- Wayne State University
- Detroit
| | - Simon Gibbons
- Research Department of Pharmaceutical and Biological Chemistry
- UCL School of Pharmacy
- London WC1N 1AX
- UK
| | - Qing Mu
- School of Pharmacy
- Fudan University
- Shanghai 201203
- China
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Raj N, Voegeli R, Rawlings AV, Gibbons S, Munday MR, Summers B, Lane ME. Variation in stratum corneum protein content as a function of anatomical site and ethnic group. Int J Cosmet Sci 2015; 38:224-31. [DOI: 10.1111/ics.12274] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 09/02/2015] [Indexed: 11/30/2022]
Affiliation(s)
- N. Raj
- School of Pharmacy; University College London; London U.K
| | - R. Voegeli
- DSM Nutritional Products Ltd.; Kaiseraugst Switzerland
| | - A. V. Rawlings
- School of Pharmacy; University College London; London U.K
| | - S. Gibbons
- School of Pharmacy; University College London; London U.K
| | - M. R. Munday
- School of Pharmacy; University College London; London U.K
| | - B. Summers
- Photobiology Laboratory; Sefako Makgatho University; Mednusa South Africa
| | - M. E. Lane
- School of Pharmacy; University College London; London U.K
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Gibbons S. Novel psychoactive substances: A chemical overview for the toxicologist. Toxicol Lett 2015. [DOI: 10.1016/j.toxlet.2015.08.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Lehtola V, Luomajoki H, Leinonen V, Gibbons S, Airaksinen O. Efficacy of movement control exercise versus general exercise on recurrent sub-acute low back pain: a randomized controlled trial. Physiotherapy 2015. [DOI: 10.1016/j.physio.2015.03.1679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Liu T, Wang S, Xu L, Fu W, Gibbons S, Mu Q. Sesquiterpenoids with Anti-MDRStaphylococcus aureusActivities fromFerula ferulioides. Chem Biodivers 2015; 12:599-614. [DOI: 10.1002/cbdv.201400150] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Indexed: 11/10/2022]
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46
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Schiavone B, Verotta L, Rosato A, Marilena M, Gibbons S, Bombardelli E, Franchini C, Corbo F. Anticancer and Antibacterial Activity of Hyperforin and Its Derivatives. Anticancer Agents Med Chem 2014; 14:1397-1401. [DOI: 10.2174/1871520614999140829122803] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 08/09/2014] [Accepted: 08/22/2014] [Indexed: 11/22/2022]
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Hussain H, Al-Harrasi A, Al-Rawahi A, Green IR, Gibbons S. Fruitful decade for antileishmanial compounds from 2002 to late 2011. Chem Rev 2014; 114:10369-428. [PMID: 25253511 DOI: 10.1021/cr400552x] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Hidayat Hussain
- UoN Chair of Oman's Medicinal Plants and Marine Natural Products, University of Nizwa , P.O. Box 33, Birkat Al Mauz, Nizwa 616, Sultanate of Oman
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Said MM, Gibbons S, Moffat AC, Zloh M. Rapid detection of sildenafil analogue in Eurycoma longifolia products using a new two-tier procedure of the near infrared (NIR) spectra database. Food Chem 2014; 158:296-301. [DOI: 10.1016/j.foodchem.2014.02.125] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 09/28/2013] [Accepted: 02/23/2014] [Indexed: 11/16/2022]
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Coqueiro A, Regasini LO, Stapleton P, da Silva Bolzani V, Gibbons S. In Vitro Antibacterial Activity of Prenylated Guanidine Alkaloids from Pterogyne nitens and Synthetic Analogues. J Nat Prod 2014; 77:1972-1975. [PMID: 25089583 DOI: 10.1021/np500281c] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The present investigation deals with the antibiotic activity of eight natural guanidine alkaloids and two synthetic analogues against a variety of clinically relevant methicillin-resistant Staphylococcus aureus strains. Galegine (1) and pterogynidine (2) were the most potent compounds, with a minimum inhibitory concentration of 4 mg/L, to all tested strains. The preliminary chemical features correlating to anti-MRSA activity showed that the size of the side chain and the substitution pattern in the guanidine core played a key role in the antibacterial activity of the imino group. Guanidine alkaloids 1 and 2 are promising molecular models for further synthetic derivatives and, thus, for medicinal chemistry studies.
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Affiliation(s)
- Aline Coqueiro
- Department of Organic Chemistry, Institute of Chemistry, São Paulo State University , Rua Prof. Francisco Degni 55, Araraquara14800-900, Brazil
- Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy , 29-39 Brunswick Square, London WC1N 1AX, United Kingdom
| | - Luis Octávio Regasini
- Department of Organic Chemistry, Institute of Chemistry, São Paulo State University , Rua Prof. Francisco Degni 55, Araraquara14800-900, Brazil
| | - Paul Stapleton
- Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy , 29-39 Brunswick Square, London WC1N 1AX, United Kingdom
| | - Vanderlan da Silva Bolzani
- Department of Organic Chemistry, Institute of Chemistry, São Paulo State University , Rua Prof. Francisco Degni 55, Araraquara14800-900, Brazil
| | - Simon Gibbons
- Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy , 29-39 Brunswick Square, London WC1N 1AX, United Kingdom
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Yalçın FN, Ersöz T, Bedir E, Dönmez AA, Stavri M, Zloh M, Gibbons S, Çaliş İ. Amanicadol, a Pimarane-type Diterpene from Phlomis amanica Vierch. ACTA ACUST UNITED AC 2014. [DOI: 10.1515/znb-2006-1118] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Fractionation of the methanol extract of Phlomis amanica resulted in the isolation of a new pimarane type diterpene, amanicadol (1), together with the known glycosides lamiide, verbascoside (= acteoside), syringaresinol-4-O-β -glucoside, liriodendrin, syringin, and a caffeic acid ester, chlorogenic acid. The structure of the new compound was established on the basis of extensive 1D and 2D NMR spectroscopic data interpretation. Molecular modeling studies on 1 were conducted and showed that it exhibited low conformational flexibility. Additionally, NMR chemical shifts were calculated for 1 in vacuo, and calculated values were in very close agreement with those found experimentally.
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Affiliation(s)
- Funda N. Yalçın
- Hacettepe University, Faculty of Pharmacy, Department of Pharmacognosy, 06100, Sıhhiye, Ankara, Turkey
| | - Tayfun Ersöz
- Hacettepe University, Faculty of Pharmacy, Department of Pharmacognosy, 06100, Sıhhiye, Ankara, Turkey
| | - Erdal Bedir
- Ege University, Faculty of Engineering, Department of Bioengineering, 35100, Bornova, Izmir, Turkey
| | - Ali A. Dönmez
- Hacettepe University, Faculty of Science, Department of Biology, 06532, Beytepe, Ankara, Turkey
| | - Michael Stavri
- Centre for Pharmacognosy and Phytotherapy, The School of Pharmacy, University of London
| | - Mire Zloh
- Department of Pharmaceutical and Biological Chemistry, The School of Pharmacy, University of London, 29 – 39 Brunswick Square, London WC1N 1AX, United Kingdom
| | - Simon Gibbons
- Centre for Pharmacognosy and Phytotherapy, The School of Pharmacy, University of London, 29 – 39 Brunswick Square, London WC1N 1AX, United Kingdom
| | - İhsan Çaliş
- Hacettepe University, Faculty of Pharmacy, Department of Pharmacognosy, 06100, Sıhhiye, Ankara, Turkey
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