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Pradeep SD, Gopalakrishnan AK, Manoharan DK, Soumya RS, Gopalan RK, Mohanan PV. Isatin derived novel Schiff bases: An efficient pharmacophore for versatile biological applications. J Mol Struct 2023. [DOI: 10.1016/j.molstruc.2022.134121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Marongiu L, Burkard M, Lauer UM, Hoelzle LE, Venturelli S. Reassessment of Historical Clinical Trials Supports the Effectiveness of Phage Therapy. Clin Microbiol Rev 2022; 35:e0006222. [PMID: 36069758 PMCID: PMC9769689 DOI: 10.1128/cmr.00062-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Phage therapy has become a hot topic in medical research due to the increasing prevalence of antibiotic-resistant bacteria strains. In the treatment of bacterial infections, bacteriophages have several advantages over antibiotics, including strain specificity, lack of serious side effects, and low development costs. However, scientists dismissed the clinical success of early clinical trials in the 1940s, slowing the adoption of this promising antibacterial application in Western countries. The current study used statistical methods commonly used in modern meta-analysis to reevaluate early 20th-century studies and compare them with clinical trials conducted in the last 20 years. Using a random effect model, the development of disease after treatment with or without phages was measured in odds ratios (OR) with 95% confidence intervals (CI). Based on the findings of 17 clinical trials conducted between 1921 and 1940, phage therapy was effective (OR = 0.21, 95% CI = 0.10 to 0.44, P value < 0.0001). The current study includes a topic review on modern clinical trials; four could be analyzed, indicating a noneffective therapy (OR = 2.84, 95% CI = 1.53 to 5.27, P value = 0.0009). The results suggest phage therapy was surprisingly less effective than standard treatments in resolving bacterial infections. However, the results were affected by the small sample set size. This work also contextualizes the development of phage therapy in the early 20th century and highlights the expansion of phage applications in the last few years. In conclusion, the current review shows phage therapy is no longer an underestimated tool in the treatment of bacterial infections.
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Affiliation(s)
- Luigi Marongiu
- Department of Biochemistry of Nutrition, University of Hohenheim, Stuttgart, Germany
- Department of Internal Medicine VIII, University Hospital Tuebingen, Tuebingen, Germany
| | - Markus Burkard
- Department of Biochemistry of Nutrition, University of Hohenheim, Stuttgart, Germany
| | - Ulrich M. Lauer
- Department of Internal Medicine VIII, University Hospital Tuebingen, Tuebingen, Germany
| | - Ludwig E. Hoelzle
- Institute of Animal Science, University of Hohenheim, Stuttgart, Germany
- HoLMiR-Hohenheim Center for Livestock Microbiome Research, University of Hohenheim, Stuttgart, Germany
| | - Sascha Venturelli
- Department of Biochemistry of Nutrition, University of Hohenheim, Stuttgart, Germany
- Institute of Physiology, Department of Vegetative and Clinical Physiology, University Hospital Tuebingen, Tuebingen, Germany
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Coordination Chemistry, Antibacterial Screening, and In Silico ADME Study of Mononuclear NiII and CuII Complexes of Asymmetric Schiff Base of Streptomycin and Aniline. J CHEM-NY 2022. [DOI: 10.1155/2022/3881217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Two novel metal complexes, that is, Ni (StmAn)2(4) and Cu (StmAn)2(5), were synthesized from unsymmetrical Schiff base ligand StmAn (3). The ligand was prepared by refluxing streptomycin (2) and aniline (1). They were characterized by elemental microanalysis, conductivity measurements, and spectroscopic techniques such as 1H NMR, FT-IR, ESI-mass, and electronic absorption spectral study. Interestingly, the study revealed metal coordination through azomethine nitrogen and N-atom of NH-CH3 of N-methyl-L-glucosamine unit of streptomycin. The electronic absorption spectral study supported an octahedral geometry for complex 4 and a tetrahedral geometry for complex 5. Particle size calculation by Scherrer’s formula indicated their nanocrystalline nature. The geometry optimization of the complexes was achieved by running an MM2 job in Gaussian supported Cs-ChemOffice ultra-12.0.1 and ArgusLab 4.0.1 version software. Based on SwissADME predictions, a theoretical drug profile was generated by analyzing absorption, distribution, metabolism, excretion, and toxicity (ADMET) scores of the compounds. They were screened for in vitro antibacterial activity study against four clinical pathogens such as E. coli, S. pneumoniae, P. vulgaris, and S. aureus. Minimum inhibitory concentration (MIC) study demonstrated greater inhibitory potency of complex (4) (0.024 g/L) for S. aureus relative to ligand (3) and complex (5). Studies show that metal complexes are more toxic to bacteria.
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Dassanayake MK, Khoo TJ, An J. Antibiotic resistance modifying ability of phytoextracts in anthrax biological agent Bacillus anthracis and emerging superbugs: a review of synergistic mechanisms. Ann Clin Microbiol Antimicrob 2021; 20:79. [PMID: 34856999 PMCID: PMC8641154 DOI: 10.1186/s12941-021-00485-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Accepted: 11/22/2021] [Indexed: 01/17/2023] Open
Abstract
Background and objectives The chemotherapeutic management of infections has become challenging due to the global emergence of antibiotic resistant pathogenic bacteria. The recent expansion of studies on plant-derived natural products has lead to the discovery of a plethora of phytochemicals with the potential to combat bacterial drug resistance via various mechanisms of action. This review paper summarizes the primary antibiotic resistance mechanisms of bacteria and also discusses the antibiotic-potentiating ability of phytoextracts and various classes of isolated phytochemicals in reversing antibiotic resistance in anthrax agent Bacillus anthracis and emerging superbug bacteria. Methods Growth inhibitory indices and fractional inhibitory concentration index were applied to evaluate the in vitro synergistic activity of phytoextract-antibiotic combinations in general. Findings A number of studies have indicated that plant-derived natural compounds are capable of significantly reducing the minimum inhibitory concentration of standard antibiotics by altering drug-resistance mechanisms of B. anthracis and other superbug infection causing bacteria. Phytochemical compounds allicin, oleanolic acid, epigallocatechin gallate and curcumin and Jatropha curcas extracts were exceptional synergistic potentiators of various standard antibiotics. Conclusion Considering these facts, phytochemicals represents a valuable and novel source of bioactive compounds with potent antibiotic synergism to modulate bacterial drug-resistance.
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Affiliation(s)
- Mackingsley Kushan Dassanayake
- School of Pharmacy, Faculty of Science and Engineering, University of Nottingham Malaysia, Jalan Broga, 43500, Semenyih, Malaysia.
| | - Teng-Jin Khoo
- School of Pharmacy, Faculty of Science and Engineering, University of Nottingham Malaysia, Jalan Broga, 43500, Semenyih, Malaysia
| | - Jia An
- Singapore Centre for 3D Printing, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, Singapore
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Niu JY, Yin IX, Wu WKK, Li QL, Mei ML, Chu CH. Antimicrobial peptides for the prevention and treatment of dental caries: A concise review. Arch Oral Biol 2020; 122:105022. [PMID: 33418434 DOI: 10.1016/j.archoralbio.2020.105022] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 12/04/2020] [Accepted: 12/05/2020] [Indexed: 10/22/2022]
Abstract
The objective of this study was to perform a comprehensive review of the use of antimicrobial peptides for the prevention and treatment of dental caries. The study included publications in the English language that addressed the use of antimicrobial peptides in the prevention and treatment of caries. These publications were also searchable on PubMed, Web of Science, Embase, Scopus, the Collection of Anti-Microbial Peptides and the Antimicrobial Peptide Database. A total of 3,436 publications were identified, and 67 publications were included. Eight publications reported seven natural human antimicrobial peptides as bactericidal to Streptococcus mutans. Fifty-nine publications reported 43 synthetic antimicrobial peptides developed to mimic natural antimicrobial peptides, fusing peptides with functional sequences and implementing new designs. The 43 synthetic antimicrobial peptides were effective against Streptococcus mutans, and nine peptides specifically targeted Streptococcus mutans. Ten antimicrobial peptides had an affinity for hydroxyapatite to prevent bacterial adhesion. Six antimicrobial peptides were also antifungal. Four antimicrobial peptides promoted remineralisation or prevented the demineralisation of teeth by binding calcium to hydroxyapatite. In conclusion, this study identified 67 works in the literature that reported seven natural and 43 synthetic antimicrobial peptides for the prevention and treatment of caries. Most of the antimicrobial peptides were bactericidal, and some prevented bacterial adhesion. A few antimicrobial peptides displayed remineralising properties with hydroxyapatite.
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Affiliation(s)
- John Yun Niu
- Faculty of Dentistry, The University of Hong Kong, Hong Kong, China.
| | - Iris Xiaoxue Yin
- Faculty of Dentistry, The University of Hong Kong, Hong Kong, China.
| | - William Ka Kei Wu
- Department of Anaesthesia & Intensive Care, The Chinese University of Hong Kong, Hong Kong, China.
| | - Quan-Li Li
- School of Stomatology, Anhui Medical University, Hefei, China.
| | - May Lei Mei
- Faculty of Dentistry, The University of Hong Kong, Hong Kong, China; Faculty of Dentistry, University of Otago, Dunedin, New Zealand.
| | - Chun Hung Chu
- Faculty of Dentistry, The University of Hong Kong, Hong Kong, China.
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Kumbar VM, Peram MR, Kugaji MS, Shah T, Patil SP, Muddapur UM, Bhat KG. Effect of curcumin on growth, biofilm formation and virulence factor gene expression of Porphyromonas gingivalis. Odontology 2020; 109:18-28. [PMID: 32279229 DOI: 10.1007/s10266-020-00514-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 03/29/2020] [Indexed: 02/06/2023]
Abstract
Porphyromonas gingivalis is a keystone pathogen and major colonizer in host tissue which plays a pivotal role in periodontitis among the other polymicrobial infections. Increasing facts demonstrate that curcumin has antibacterial activity and anti-biofilm effect against the periodontopathogens through diverse mechanisms that have a positive impact on periodontal health. The present study was aimed to elucidate the effect of curcumin on biofilm formation and virulence factor gene expression of P. gingivalis. By using gene expression studies, we exploited the mechanism of anti-biofilm effects of curcumin on P. gingivalis. The minimum inhibitory concentration and minimum bactericidal concentration of curcumin for both ATCC and clinical strains of P. gingivalis were found to be 62.5 and 125 µg ml-1 respectively. Curcumin prevented bacterial adhesion and biofilm formation in a dose-dependent manner. Further, curcumin attenuated the virulence of P. gingivalis by reducing the expression of genes coding for major virulence factors, including adhesions (fimA, hagA, and hagB) and proteinases (rgpA, rgpB, and kgp). The results indicated that curcumin has shown anti-biofilm as well as antibacterial activity against P. gingivalis. Further, curcumin because of its pleiotropic actions could be a simple and inexpensive therapeutic strategy in the treatment of periodontal disease.
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Affiliation(s)
- Vijay M Kumbar
- Central Research Laboratory, Maratha Mandal's Nathajirao G. Halgekar Institute of Dental Sciences and Research Centre, Near KSRP Ground, Bauxite road, Belgaum, Karnataka, 590 010, India
| | - Malleswara Rao Peram
- Central Research Laboratory, Maratha Mandal's Nathajirao G. Halgekar Institute of Dental Sciences and Research Centre, Near KSRP Ground, Bauxite road, Belgaum, Karnataka, 590 010, India
- Department of Pharmaceutics, Maratha Mandal's College of Pharmacy, Belgaum, Karnataka, 590 010, India
| | - Manohar S Kugaji
- Central Research Laboratory, Maratha Mandal's Nathajirao G. Halgekar Institute of Dental Sciences and Research Centre, Near KSRP Ground, Bauxite road, Belgaum, Karnataka, 590 010, India
| | - Tejas Shah
- Department of Biotechnology, Sinhgad College of Engineering, Affiliated to Savitribai Phule Pune University, Vadgaon Budruk, Sinhagad Road, Pune, Maharashtra, 411 0 41, India
| | - Sanjivani P Patil
- Central Research Laboratory, Maratha Mandal's Nathajirao G. Halgekar Institute of Dental Sciences and Research Centre, Near KSRP Ground, Bauxite road, Belgaum, Karnataka, 590 010, India
| | - Uday M Muddapur
- Department of Biotechnology, KLE Technological University (Formerly Known as B.V.Bhoomaraddi College of Engineering and Technology), BVB Campus, Hubli, Karnataka, 580031, India
| | - Kishore G Bhat
- Central Research Laboratory, Maratha Mandal's Nathajirao G. Halgekar Institute of Dental Sciences and Research Centre, Near KSRP Ground, Bauxite road, Belgaum, Karnataka, 590 010, India.
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7
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Espinoza-Culupú A, Mendes E, Vitorino HA, da Silva PI, Borges MM. Mygalin: An Acylpolyamine With Bactericidal Activity. Front Microbiol 2020; 10:2928. [PMID: 31998255 PMCID: PMC6965172 DOI: 10.3389/fmicb.2019.02928] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 12/05/2019] [Indexed: 01/15/2023] Open
Abstract
Inappropriate use of antibiotics favors the selection and spread of resistant bacteria. To reduce the spread of these bacteria, finding new molecules with activity is urgent and necessary. Several polyamine analogs have been constructed and used to control microorganisms and tumor cells. Mygalin is a synthetic acylpolyamine, which are analogs of spermidine, derived from the hemolymph of the spider Acanthoscurria gomesiana. The effective activity of polyamines and their analogs has been associated with their structure. The presence of two acyl groups in the Mygalin structure may give this molecule a specific antibacterial activity. The aim of this study was to identify the mechanisms involved in the interaction of Mygalin with Escherichia coli to clarify its antimicrobial action. The results indicated that Mygalin exhibits intense dose and time-dependent bactericidal activity. Treatment of E. coli with this molecule caused membrane rupture, inhibition of DNA synthesis, DNA damage, and morphological changes. The esterase activity increased along with the intracellular production of reactive oxygen species (ROS) after treatment of the bacteria with Mygalin. In addition, this molecule was able to sequester iron and bind to LPS. We have shown that Mygalin has bactericidal activity with underlying mechanisms involving ROS generation and chelation of iron ions that are necessary for bacterial metabolism, which may contribute to its microbicidal activity. Taken together, our data suggest that Mygalin can be explored as a new alternative drug with antimicrobial potential against Gram-negative bacteria or other infectious agents.
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Affiliation(s)
- Abraham Espinoza-Culupú
- Ph.D. Program in Biotechnology, University of São Paulo, São Paulo, Brazil.,Bacteriology Laboratory, Butantan Institute, São Paulo, Brazil
| | | | - Hector Aguilar Vitorino
- Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Science, Columbus Center, Baltimore, MD, United States
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Prasad S, Radhakrishna V, Ravi TK. Synthesis, spectroscopic and antibacterial studies of some schiff bases of 4-(4-bromophenyl)-6-(4-chlorophenyl)-2-aminopyrimidine. ARAB J CHEM 2019. [DOI: 10.1016/j.arabjc.2016.03.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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9
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Wang X, Chen J, Wang W, Jaunarajs A, Wang X. Tryptoline-based benzothiazoles re-sensitize MRSA to β-lactam antibiotics. Bioorg Med Chem 2019; 27:115095. [PMID: 31521461 PMCID: PMC6779328 DOI: 10.1016/j.bmc.2019.115095] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 09/04/2019] [Accepted: 09/06/2019] [Indexed: 01/03/2023]
Abstract
Resistance-modifying agents (RMAs) offer a promising solution to combat bacterial antibiotic resistance. Here we report the discovery and structure-activity relationships of a new class of RMAs with a novel tryptoline-based benzothiazole scaffold. Our most potent compound in this series (4ad) re-sensitizes multiple MRSA strains to cephalosporins at low concentrations (2 μg/mL) and has low mammalian cytotoxicity with a half growth inhibitory concentration (GI50) > 100 μg/mL in human cervical carcinoma (HeLa) cells. In addition, the same core scaffold with different substitutions also gives good antibacterial activity against MRSA.
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Affiliation(s)
- Xinfeng Wang
- Department of Chemistry, University of Colorado, Boulder, CO 80309, United States
| | - Jinsen Chen
- Department of Chemistry, University of Colorado, Boulder, CO 80309, United States
| | - Wei Wang
- Department of Chemistry, University of Colorado, Boulder, CO 80309, United States
| | - Anna Jaunarajs
- Department of Chemistry, University of Colorado, Boulder, CO 80309, United States
| | - Xiang Wang
- Department of Chemistry, University of Colorado, Boulder, CO 80309, United States.
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10
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Lakshmi S, Avti PK, Hegde G. Activated carbon nanoparticles from biowaste as new generation antimicrobial agents: A review. ACTA ACUST UNITED AC 2018. [DOI: 10.1016/j.nanoso.2018.08.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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11
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Viana Marques DDA, Machado SEF, Ebinuma VCS, Duarte CDAL, Converti A, Porto ALF. Production of β-Lactamase Inhibitors by Streptomyces Species. Antibiotics (Basel) 2018; 7:E61. [PMID: 30018235 PMCID: PMC6163296 DOI: 10.3390/antibiotics7030061] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 07/07/2018] [Accepted: 07/12/2018] [Indexed: 12/11/2022] Open
Abstract
β-Lactamase inhibitors have emerged as an effective alternative to reduce the effects of resistance against β-lactam antibiotics. The Streptomyces genus is known for being an exceptional natural source of antimicrobials and β-lactamase inhibitors such as clavulanic acid, which is largely applied in clinical practice. To protect against the increasing prevalence of multidrug-resistant bacterial strains, new antibiotics and β-lactamase inhibitors need to be discovered and developed. This review will cover an update about the main β-lactamase inhibitors producers belonging to the Streptomyces genus; advanced methods, such as genetic and metabolic engineering, to enhance inhibitor production compared with wild-type strains; and fermentation and purification processes. Moreover, clinical practice and commercial issues are discussed. The commitment of companies and governments to develop innovative strategies and methods to improve the access to new, efficient, and potentially cost-effective microbial products to combat the antimicrobial resistance is also highlighted.
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Affiliation(s)
- Daniela de Araújo Viana Marques
- Campus Serra Talhada, University of Pernambuco, Avenida Custódio Conrado, 600, AABB, Serra Talhada, Pernambuco 56912-550, Brazil.
| | - Suellen Emilliany Feitosa Machado
- Department of Antibiotics, Federal University of Pernambuco, Avenida da Engenharia, 2° andar, Cidade Universitária, Recife, Pernambuco 50740-600, Brazil.
| | - Valéria Carvalho Santos Ebinuma
- Department of Bioprocesses and Biotechnology, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Rodovia Araraquara-Jaú/Km 01, Araraquara 14800-903, Brazil.
| | | | - Attilio Converti
- Department of Civil, Chemical and Environmental Engineering, Chemical Pole, University of Genoa, Via Opera Pia 15, 16145 Genoa, Italy.
| | - Ana Lúcia Figueiredo Porto
- Department of Morphology and Animal Physiology, Federal Rural University of Pernambuco, Av. Dom Manoel de Medeiros, Recife, Pernambuco 52171-900, Brazil.
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12
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Antimicrobial resistance mechanisms and potential synthetic treatments. Future Sci OA 2018; 4:FSO290. [PMID: 29682325 PMCID: PMC5905577 DOI: 10.4155/fsoa-2017-0109] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 01/15/2018] [Indexed: 12/26/2022] Open
Abstract
Since the discovery of antibiotics by Sir Alexander Fleming they have been used throughout medicine and play a vital role in combating microorganisms. However, with their vast use, development of resistance has become more prevalent and their use is currently under threat. Antibiotic resistance poses a global threat to human and animal health, with many bacterial species having developed some form of resistance and in some cases within a year of first exposure to antimicrobial agents. This review aims to examine some of the mechanisms behind resistance. Additionally, re-engineering organisms, re-sensitizing bacteria to antibiotics and gene-editing techniques such as the clustered regularly interspaced short palindromic repeats-Cas9 system are providing novel approaches to combat bacterial resistance. To that extent, we have reviewed some of these novel and innovative technologies. In 1928, penicillin was discovered, changing the field of modern medicine as it provided an opportunity to treat microbial infections. Since then, microorganisms such as bacteria have evolved and now have the ability to resist a wide variety of agents that might otherwise prevent their growth. By 2050, it is estimated that around 10 million lives each year will be lost due to these bacteria. This article provides an insight into how bacteria resist antibiotics and potential new methods of treating these organisms.
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Antibacterial Activity of the Non-Cytotoxic Peptide (p-BthTX-I)₂ and Its Serum Degradation Product against Multidrug-Resistant Bacteria. Molecules 2017; 22:molecules22111898. [PMID: 29113051 PMCID: PMC6150245 DOI: 10.3390/molecules22111898] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 10/30/2017] [Accepted: 10/31/2017] [Indexed: 12/17/2022] Open
Abstract
Antimicrobial peptides can be used systemically, however, their susceptibility to proteases is a major obstacle in peptide-based therapeutic development. In the present study, the serum stability of p-BthTX-I (KKYRYHLKPFCKK) and (p-BthTX-I)₂, a p-BthTX-I disulfide-linked dimer, were analyzed by mass spectrometry and analytical high-performance liquid chromatography (HPLC). Antimicrobial activities were assessed by determining their minimum inhibitory concentrations (MIC) using cation-adjusted Mueller-Hinton broth. Furthermore, biofilm eradication and time-kill kinetics were performed. Our results showed that p-BthTX-I and (p-BthTX-I)₂ were completely degraded after 25 min. Mass spectrometry showed that the primary degradation product was a peptide that had lost four lysine residues on its C-terminus region (des-Lys12/Lys13-(p-BthTX-I)₂), which was stable after 24 h of incubation. The antibacterial activities of the peptides p-BthTX-I, (p-BthTX-I)₂, and des-Lys12/Lys13-(p-BthTX-I)₂ were evaluated against a variety of bacteria, including multidrug-resistant strains. Des-Lys12/Lys13-(p-BthTX-I)₂ and (p-BthTX-I)₂ degraded Staphylococcus epidermidis biofilms. Additionally, both the peptides exhibited bactericidal activities against planktonic S. epidermidis in time-kill assays. The emergence of bacterial resistance to a variety of antibiotics used in clinics is the ultimate challenge for microbial infection control. Therefore, our results demonstrated that both peptides analyzed and the product of proteolysis obtained from (p-BthTX-I)₂ are promising prototypes as novel drugs to treat multidrug-resistant bacterial infections.
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Afifi TH, Okasha RM, Ahmed HEA, Ilaš J, Saleh T, Abd-El-Aziz AS. Structure-activity relationships and molecular docking studies of chromene and chromene based azo chromophores: A novel series of potent antimicrobial and anticancer agents. EXCLI JOURNAL 2017; 16:868-902. [PMID: 28828001 PMCID: PMC5547389 DOI: 10.17179/excli2017-356] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 06/09/2017] [Indexed: 01/31/2023]
Abstract
The design of novel materials with significant biological properties is a main target in drug design research. Chromene compounds represent an interesting medicinal scaffold in drug replacement systems. This report illustrates a successful synthesis and characterization of two novel series of chromene compounds using multi-component reactions. The synthesis of the first example of azo chromophores containing chromene moieties has also been established using the same methodology. The antimicrobial activity of the new molecules has been tested against seven human pathogens including two Gm+ve, two Gm-ve bacteria, and four fungi, and the results of the inhibition zones with minimum inhibitory concentrations were reported as compared to reference drugs. All the designed compounds showed significant potent antimicrobial activities, among of them, four potent compounds 4b, 4c, 13e, and 13i showed promising MIC from 0.007 to 3.9 µg/mL. In addition, antiproliferative analysis against three target cell lines was examined for the novel compounds. Compounds 4a, 4b, 4c, and 7c possessed significant antiproliferative activity against three cell lines with an IC50 of 0.3 to 2 µg/mL. Apoptotic analysis was performed for the most potent compounds via caspase enzyme activity assays as a potential mechanism for their antiproliferative effects. Finally, the computational 2D QSAR and docking simulations were accomplished for structure-activity relationship analyses.
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Affiliation(s)
- Tarek H Afifi
- Chemistry Department, Faculty of Science, Taibah University, 30002, Al-Madinah Al-Munawarah, Saudi Arabia
| | - Rawda M Okasha
- Chemistry Department, Faculty of Science, Taibah University, 30002, Al-Madinah Al-Munawarah, Saudi Arabia
| | - Hany E A Ahmed
- Pharmacognosy and Pharmaceutical Chemistry Department, Pharmacy College, Taibah University, Al-Madinah Al-Munawarah, Saudi Arabia.,Pharmaceutical Organic Chemistry Department, Faculty of Pharmacy, Al-Azhar University, Cairo, Egypt
| | - Janez Ilaš
- Faculty of Pharmacy, University of Ljubljana, Aškerceva 7, 1000 Ljubljana, Slovenia
| | - Tarek Saleh
- Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, ON, N1G 2W1, Canada
| | - Alaa S Abd-El-Aziz
- Chemistry Department, Faculty of Science, University of Prince Edward Island, Charlottetown, Prince Edward Island C1A 4P3, Canada
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15
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Antimicrobial Resistance and the Alternative Resources with Special Emphasis on Plant-Based Antimicrobials-A Review. PLANTS 2017; 6:plants6020016. [PMID: 28394295 PMCID: PMC5489788 DOI: 10.3390/plants6020016] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 03/20/2017] [Accepted: 03/23/2017] [Indexed: 11/16/2022]
Abstract
Indiscriminate and irrational use of antibiotics has created an unprecedented challenge for human civilization due to microbe’s development of antimicrobial resistance. It is difficult to treat bacterial infection due to bacteria’s ability to develop resistance against antimicrobial agents. Antimicrobial agents are categorized according to their mechanism of action, i.e., interference with cell wall synthesis, DNA and RNA synthesis, lysis of the bacterial membrane, inhibition of protein synthesis, inhibition of metabolic pathways, etc. Bacteria may become resistant by antibiotic inactivation, target modification, efflux pump and plasmidic efflux. Currently, the clinically available treatment is not effective against the antibiotic resistance developed by some bacterial species. However, plant-based antimicrobials have immense potential to combat bacterial, fungal, protozoal and viral diseases without any known side effects. Such plant metabolites include quinines, alkaloids, lectins, polypeptides, flavones, flavonoids, flavonols, coumarin, terpenoids, essential oils and tannins. The present review focuses on antibiotic resistance, the resistance mechanism in bacteria against antibiotics and the role of plant-active secondary metabolites against microorganisms, which might be useful as an alternative and effective strategy to break the resistance among microbes.
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16
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The antibiotic resistance crisis, with a focus on the United States. J Antibiot (Tokyo) 2017; 70:520-526. [PMID: 28246379 DOI: 10.1038/ja.2017.30] [Citation(s) in RCA: 252] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 01/29/2017] [Accepted: 01/30/2017] [Indexed: 02/06/2023]
Abstract
Beginning with the discovery of penicillin by Alexander Fleming in the late 1920s, antibiotics have revolutionized the field of medicine. They have saved millions of lives each year, alleviated pain and suffering, and have even been used prophylactically for the prevention of infectious diseases. However, we have now reached a crisis where many antibiotics are no longer effective against even the simplest infections. Such infections often result in an increased number of hospitalizations, more treatment failures and the persistence of drug-resistant pathogens. Of particular concern are organisms such as methicillin-resistant Staphylococcus aureus, Clostridium difficile, multidrug and extensively drug-resistant Mycobacterium tuberculosis, Neisseria gonorrhoeae, carbapenem-resistant Enterobacteriaceae and bacteria that produce extended spectrum β-lactamases, such as Escherichia coli. To make matters worse, there has been a steady decline in the discovery of new and effective antibiotics for a number of reasons. These include increased costs, lack of adequate support from the government, poor returns on investment, regulatory hurdles and pharmaceutical companies that have simply abandoned the antibacterial arena. Instead, many have chosen to focus on developing drugs that will be used on a chronic basis, which will offer a greater profit and more return on investment. Therefore, there is now an urgent need to develop new and useful antibiotics to avoid returning to the 'pre-antibiotic era'. Some potential opportunities for antibiotic discovery include better economic incentives, genome mining, rational metabolic engineering, combinatorial biosynthesis and further exploration of the earth's biodiversity.
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Antibacterial Peptides: Opportunities for the Prevention and Treatment of Dental Caries. Probiotics Antimicrob Proteins 2016; 3:68. [PMID: 26781572 DOI: 10.1007/s12602-011-9076-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Dental caries is a multifactorial disease that is a growing and costly global health concern. The onset of disease is a consequence of an ecological imbalance within the dental plaque biofilm that favors specific acidogenic and aciduric caries pathogens, namely Streptococcus mutans and Streptococcus sobrinus. It is now recognized by the scientific and medical community that it is neither possible nor desirable to totally eliminate dental plaque. Conversely, the chemical biocides most commonly used for caries prevention and treatment indiscriminately attack all plaque microorganisms. These treatments also suffer from other drawbacks such as bad taste, irritability, and staining. Furthermore, the public demand for safe and natural personal hygiene products continues to rise. Therefore, there are opportunities that exist to develop new strategies for the treatment of this disease. As an alternative to conventional antibiotics, antibacterial peptides have been explored greatly over the last three decades for many different therapeutic uses. There are currently tens of hundreds of antibacterial peptides characterized across the evolutionary spectrum, and among these, many demonstrate physical and/or biological properties that may be suitable for a more targeted approach to the selective control or elimination of putative caries pathogens. Additionally, many peptides, such as nisin, are odorless, colorless, and tasteless and do not cause irritation or staining. This review focuses on antibacterial peptides for their potential role in the treatment and prevention of dental caries and suggests candidates that need to be explored further. Practical considerations for the development of antibacterial peptides as oral treatments are also discussed.
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Chase P, Enogieru I, Madoux F, Bishop E, Beer J, Scampavia L, Spicer T. An Automated Miniaturized Method to Perform and Analyze Antimicrobial Drug Synergy Assays. Assay Drug Dev Technol 2015; 14:58-66. [PMID: 26669516 DOI: 10.1089/adt.2015.672] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In the light of emerging antibiotic resistance mechanisms found in bacteria throughout the world, discovery of drugs that potentiate the effect of currently available antibiotics remains an important aspect of pharmaceutical research in the 21st century. Well-established clinical tests exist to determine synergy in vitro, but these are only optimal for low-throughput experimentation while leaving analysis of results and interpretation of high-throughput microscale assays poorly standardized. Here, we describe a miniaturized broth microdilution checkerboard assay and data analysis method in 384-well plate format that conforms to the Clinical Laboratory and Standards Institute (CLSI) methods. This method has been automated and developed to rapidly determine the synergism of current antibiotics with various beta-lactamase inhibitors emerging from our antimicrobial research efforts. This technique increases test throughput and integrity of results, and saves test compound and labor. We facilitated the interpretation of results with an automated analysis tool allowing us to rapidly qualify inter- and intraplate robustness, determine efficacy of multiple antibiotics at the same time, and standardize the results of synergy interpretation. This procedure should enhance high-throughput antimicrobial drug discovery and supersedes former techniques.
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Affiliation(s)
- Peter Chase
- Lead Identification, Department of Molecular Therapeutics, The Scripps Research Institute , Scripps Florida, Jupiter, Florida
| | - Imarhia Enogieru
- Lead Identification, Department of Molecular Therapeutics, The Scripps Research Institute , Scripps Florida, Jupiter, Florida
| | - Franck Madoux
- Lead Identification, Department of Molecular Therapeutics, The Scripps Research Institute , Scripps Florida, Jupiter, Florida
| | - Eric Bishop
- Lead Identification, Department of Molecular Therapeutics, The Scripps Research Institute , Scripps Florida, Jupiter, Florida
| | - Jacob Beer
- Lead Identification, Department of Molecular Therapeutics, The Scripps Research Institute , Scripps Florida, Jupiter, Florida
| | - Louis Scampavia
- Lead Identification, Department of Molecular Therapeutics, The Scripps Research Institute , Scripps Florida, Jupiter, Florida
| | - Timothy Spicer
- Lead Identification, Department of Molecular Therapeutics, The Scripps Research Institute , Scripps Florida, Jupiter, Florida
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Srivastava J, Chandra H, Nautiyal AR, Kalra SJS. Antimicrobial resistance (AMR) and plant-derived antimicrobials (PDA ms) as an alternative drug line to control infections. 3 Biotech 2014; 4:451-460. [PMID: 28324380 PMCID: PMC4162903 DOI: 10.1007/s13205-013-0180-y] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 10/07/2013] [Indexed: 12/26/2022] Open
Abstract
Infectious diseases caused by antimicrobial-resistant microbes (ARMs) and the treatment are the serious problems in the field of medical science today world over. The development of alternative drug line to treat such infectious diseases is urgently required. Researches on ARMs revealed the presence of membrane proteins responsible for effusing the antibiotics from the bacterial cells. Such proteins have successfully been treated by plant-derived antimicrobials (PDAms) synergistically along with the commercially available antibiotics. Such synergistic action usually inhibits the efflux pump. The enhanced activity of plant-derived antimicrobials is being researched and is considered as the future treatment strategy to cure the incurable infections. The present paper reviews the advancement made in the researches on antimicrobial resistance along with the discovery and the development of more active PDAms.
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Affiliation(s)
- Jatin Srivastava
- Department of Applied Sciences, Faculty of Environmental Science, Himalayan Institute of Technology and Management, BKT, NH 24, Lucknow, 227005, UP, India.
| | - Harish Chandra
- Department of Medicinal and Aromatic Plants, School of Agriculture and Allied Sciences, High Altitude Plant Physiology Research Center, H.N.B. Garhwal University, Srinagar, Uttrakhand, India
| | - Anant R Nautiyal
- Department of Medicinal and Aromatic Plants, School of Agriculture and Allied Sciences, High Altitude Plant Physiology Research Center, H.N.B. Garhwal University, Srinagar, Uttrakhand, India
| | - Swinder J S Kalra
- Department of Chemistry, Dayanand Anglo Vedic College, Civil Lines, Kanpur, UP, India
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Hong W, Zeng J, Xie J. Antibiotic drugs targeting bacterial RNAs. Acta Pharm Sin B 2014; 4:258-65. [PMID: 26579393 PMCID: PMC4629089 DOI: 10.1016/j.apsb.2014.06.012] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 06/04/2014] [Accepted: 06/20/2014] [Indexed: 10/26/2022] Open
Abstract
RNAs have diverse structures that include bulges and internal loops able to form tertiary contacts or serve as ligand binding sites. The recent increase in structural and functional information related to RNAs has put them in the limelight as a drug target for small molecule therapy. In addition, the recognition of the marked difference between prokaryotic and eukaryotic rRNA has led to the development of antibiotics that specifically target bacterial rRNA, reduce protein translation and thereby inhibit bacterial growth. To facilitate the development of new antibiotics targeting RNA, we here review the literature concerning such antibiotics, mRNA, riboswitch and tRNA and the key methodologies used for their screening.
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Affiliation(s)
| | | | - Jianping Xie
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing 400715, China
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Allahverdiyev AM, Bagirova M, Abamor ES, Ates SC, Koc RC, Miraloglu M, Elcicek S, Yaman S, Unal G. The use of platensimycin and platencin to fight antibiotic resistance. Infect Drug Resist 2013; 6:99-114. [PMID: 24082790 PMCID: PMC3785399 DOI: 10.2147/idr.s25076] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Infectious diseases are known as one of the most life-threatening disabilities worldwide. Approximately 13 million deaths related to infectious diseases are reported each year. The only way to combat infectious diseases is by chemotherapy using antimicrobial agents and antibiotics. However, due to uncontrolled and unnecessary use of antibiotics in particular, surviving bacteria have evolved resistance against several antibiotics. Emergence of multidrug resistance in bacteria over the past several decades has resulted in one of the most important clinical health problems in modern medicine. For instance, approximately 440,000 new cases of multidrug-resistant tuberculosis are reported every year leading to the deaths of 150,000 people worldwide. Management of multidrug resistance requires understanding its molecular basis and the evolution and dissemination of resistance; development of new antibiotic compounds in place of traditional antibiotics; and innovative strategies for extending the life of antibiotic molecules. Researchers have begun to develop new antimicrobials for overcoming this important problem. Recently, platensimycin - isolated from extracts of Streptomyces platensis - and its analog platencin have been defined as promising agents for fighting multidrug resistance. In vitro and in vivo studies have shown that these new antimicrobials have great potential to inhibit methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, and penicillin-resistant Streptococcus pneumoniae by targeting type II fatty acid synthesis in bacteria. Showing strong efficacy without any observed in vivo toxicity increases the significance of these antimicrobial agents for their use in humans. However, at the present time, clinical trials are insufficient and require more research. The strong antibacterial efficacies of platensimycin and platencin may be established in clinical trials and their use in humans for coping with multidrug resistance may be allowed in the foreseeable future.
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Affiliation(s)
| | - Melahat Bagirova
- Department of Bioengineering, Yildiz Technical University, Istanbul, Turkey
| | - Emrah Sefik Abamor
- Department of Bioengineering, Yildiz Technical University, Istanbul, Turkey
| | - Sezen Canim Ates
- Department of Bioengineering, Yildiz Technical University, Istanbul, Turkey
| | - Rabia Cakir Koc
- Department of Biomedical Engineering, Yeni Yuzyil University, Istanbul, Turkey
| | - Meral Miraloglu
- Vocational School of Health Services, Cukurova University, Adana, Turkey
| | - Serhat Elcicek
- Department of Bioengineering, Firat University, Elazig, Turkey
| | - Serkan Yaman
- Department of Bioengineering, Yildiz Technical University, Istanbul, Turkey
| | - Gokce Unal
- Department of Bioengineering, Yildiz Technical University, Istanbul, Turkey
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Phillips OA, Udo EE, Abdel-Hamid ME, Varghese R. Synthesis and antibacterial activities of N-substituted-glycinyl 1H-1,2,3-triazolyl oxazolidinones. Eur J Med Chem 2013; 66:246-57. [DOI: 10.1016/j.ejmech.2013.05.041] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Revised: 05/28/2013] [Accepted: 05/29/2013] [Indexed: 11/29/2022]
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Fränzel B, Penkova M, Frese C, Metzler-Nolte N, Andreas Wolters D. Escherichia coli exhibits a membrane-related response to a small arginine- and tryptophan-rich antimicrobial peptide. Proteomics 2013; 12:2319-30. [PMID: 22685012 DOI: 10.1002/pmic.201100636] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Since multiresistant bacterial strains are more widespread and the victim numbers steadily increase, it is very important to possess a broad bandwidth of antimicrobial substances. Antibiotics often feature membrane-associated effect mechanisms. So, we present a membrane proteomic approach to shed light on the cellular response of Escherichia coli as model organism to the hexapeptide MP196, which is arginine and tryptophan rich. Analyzing integral membrane proteins are still challenging, although various detection strategies have been developed in the past. In particular, membrane proteomics in bacteria have been conducted very little due to the special physical properties of these membrane proteins. To obtain more information on the cellular response of the new compound group of small peptides, the tryptophan- and arginine-rich hexapeptide MP196 was subject to a comprehensive quantitative membrane proteomic study on E. coli by means of metabolic labeling in combination with membrane lipid analyses. This study provides in total 767 protein identifications including 185 integral membrane proteins, from which 624 could be quantified. Among these proteins, 134 were differentially expressed. Thereby, functional groups such as amino acid and membrane biosynthesis were affected, stress response could be observed, and the lipid composition of the membrane was significantly altered. Especially, the strong upregulation of the envelope stress induced protein. Spy indicates membrane damage, as well as the downregulation of the mechano-sensitive channel MscL beside others. Finally, the exceptional downregulation of transport systems strengthens these findings.
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Affiliation(s)
- Benjamin Fränzel
- Lehrstuhl für Analytische Chemie, Biomolekulare Massenspektrometrie, Fakultät für Chemie und Biochemie, Ruhr-Universität Bochum, Bochum, Germany
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de Lima Procópio RE, da Silva IR, Martins MK, de Azevedo JL, de Araújo JM. Antibiotics produced by Streptomyces. Braz J Infect Dis 2012; 16:466-71. [DOI: 10.1016/j.bjid.2012.08.014] [Citation(s) in RCA: 225] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Accepted: 05/06/2012] [Indexed: 10/27/2022] Open
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Wang ZY, Xiong M, Fu LY, Zhang HY. Oxidative DNA damage is important to the evolution of antibiotic resistance: evidence of mutation bias and its medicinal implications. J Biomol Struct Dyn 2012; 31:729-33. [PMID: 22908856 DOI: 10.1080/07391102.2012.709457] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Several (1) studies have revealed that the reactive oxygen species (ROS) induced by antibacterial stimulation accelerates the evolution of antibiotic resistance, which uncovered new links between oxygen rise and evolution and inspired new strategies to prevent antibiotic resistance. Considering many other mechanisms cause DNA mutations aside from ROS damage, evaluating the significance of oxidative DNA damage in the development of antibiotic resistance is of great interest. In this study, we examined the ratio of G:C > T:A transversion to G:C > A:T transition in drug-resistant Escherichia coli and Mycobacterium tuberculosis and found that it is significantly higher than the background values. This finding strongly suggests that ROS damage plays a critical role in the development of antibacterial resistance. Considering the long-term co-evolution between host organisms and pathogenic bacteria, we speculate that the hosts may have evolved strategies for combating antibiotic resistance by controlling DNA damage in bacteria. Analysis of the global transcriptional profiles of Staphylococcus aureus treated with berberine (derived from Berberis, a traditional antibacterial medicine) revealed that the transcription of DNA repair enzymes was markedly upregulated, whereas the antioxidant enzymes were significantly downregulated. Thus, we propose that consolidating the DNA repair systems of bacteria may be a viable strategy for preventing antibiotic resistance. (1)These authors contributed equally to this work.
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Affiliation(s)
- Zhong-Yi Wang
- National Key Laboratory of Crop Genetic Improvement, Center for Bioinformatics, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, P.R. China
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26
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Antibacterial metabolites synthesized by psychrotrophic bacteria isolated from cold-freshwater environments. Folia Microbiol (Praha) 2012; 58:127-33. [DOI: 10.1007/s12223-012-0190-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Accepted: 07/27/2012] [Indexed: 10/28/2022]
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Abstract
The emergence of bacteria that are multiply resistant to commonly used antibiotics has created the medical need for novel classes of antibacterial agents. The unique challenges to the discovery of new antibacterial drugs include the following: spectrum, selectivity, low emergence of new resistance, and high potency. With the emergence of genomic information, dozens of antibacterial targets have been pursued over the last 2 decades often using SBDD. This chapter reviews the application of structure-based drug design approaches on a selected group of antibacterial targets (DHFR, DHNA, PDF, and FabI) where significant progress has been made. We compare and contrast the different approaches and evaluate the results in terms of the biological profiles of the leads produced. Several common themes have emerged from this survey, resulting in a set of recommendations.
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Affiliation(s)
- John Finn
- Trius Therapeutics, San Diego, CA, USA.
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28
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Wenzel M, Bandow JE. Proteomic signatures in antibiotic research. Proteomics 2011; 11:3256-68. [DOI: 10.1002/pmic.201100046] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Revised: 03/13/2011] [Accepted: 03/22/2011] [Indexed: 11/06/2022]
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29
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Sarada DVL, Sreenath Kumar C, Rengasamy R. Purified C-phycocyanin from Spirulina platensis (Nordstedt) Geitler: a novel and potent agent against drug resistant bacteria. World J Microbiol Biotechnol 2011. [DOI: 10.1007/s11274-010-0516-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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30
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Al-Mahrous MM, Upton M. Discovery and development of lantibiotics; antimicrobial agents that have significant potential for medical application. Expert Opin Drug Discov 2011; 6:155-70. [PMID: 22647134 DOI: 10.1517/17460441.2011.545387] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
INTRODUCTION Antimicrobial drug resistance is driving the need for novel therapeutics. Amongst the most promising antibacterial agents that are being investigated as replacements for current therapeutic antibiotics are antibacterial peptides, such as the lanthionine-containing peptide antibiotics (lantibiotics). AREAS COVERED This review focuses on the current methods used for discovery of potentially exploitable lantibiotics for medical applications and discusses relevant recent innovations that will have a positive impact on the discovery of useful lantibiotics. EXPERT OPINION Recent technological advances in a number of fields mean that increased research into the identification and characterisation of new lantibiotics is feasible. We need to increase our understanding of the various mechanisms of antibacterial action exhibited by lantibiotics and apply this knowledge to peptide engineering or novel practical applications. The advent of next-generation sequencing approaches now negate the need for extensive reverse genetics and employment of bioinformatics approaches is greatly assisting the identification of potentially useful inhibitors in the genomes of a range of clinically significant bacteria. These advances in genetic analysis and engineering will facilitate increased exploitation of lantibiotics in medical therapy.
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Affiliation(s)
- Mohammed M Al-Mahrous
- University of Manchester, School of Translational Medicine, Department of Medical Microbiology, Clinical Sciences Building, Manchester Royal Infirmary, Oxford Road, Manchester, M13 9WL, UK +44 1 161 276 8828 ; +44 0 161 276 8826 ;
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Brötz-Oesterhelt H, Sass P. Postgenomic strategies in antibacterial drug discovery. Future Microbiol 2010; 5:1553-79. [DOI: 10.2217/fmb.10.119] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
During the last decade the field of antibacterial drug discovery has changed in many aspects including bacterial organisms of primary interest, discovery strategies applied and pharmaceutical companies involved. Target-based high-throughput screening had been disappointingly unsuccessful for antibiotic research. Understanding of this lack of success has increased substantially and the lessons learned refer to characteristics of targets, screening libraries and screening strategies. The ‘genomics’ approach was replaced by a diverse array of discovery strategies, for example, searching for new natural product leads among previously abandoned compounds or new microbial sources, screening for synthetic inhibitors by targeted approaches including structure-based design and analyses of focused libraries and designing resistance-breaking properties into antibiotics of established classes. Furthermore, alternative treatment options are being pursued including anti-virulence strategies and immunotherapeutic approaches. This article summarizes the lessons learned from the genomics era and describes discovery strategies resulting from that knowledge.
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Affiliation(s)
- Heike Brötz-Oesterhelt
- AiCuris, Wuppertal, Germany, Institute for Pharmaceutical Biology, University of Duesseldorf, Universitätsstrasse 1, Building 26.23.U1, Germany
| | - Peter Sass
- Institute of Medical Microbiology, Immunology & Parasitology, Pharmaceutical Microbiology Section, University of Bonn, Germany
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Corynebacterium glutamicum exhibits a membrane-related response to a small ferrocene-conjugated antimicrobial peptide. J Biol Inorg Chem 2010; 15:1293-303. [PMID: 20658302 DOI: 10.1007/s00775-010-0689-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2010] [Accepted: 07/06/2010] [Indexed: 10/19/2022]
Abstract
Multiresistant bacteria are becoming more and more widespread. It is therefore necessary to have new compound groups in hand, such as small cationic peptides, to cope with these challenges. In this work, we present a comprehensive approach by monitoring protein expression profiles in a gram-positive bacterium (Corynebacterium glutamicum) to investigate the cellular response to such a compound, a ferrocene-conjugated arginine- and tryptophan-rich pentapeptide. To achieve this, a proteomic outline was performed where the compound-treated sample was compared with an untreated control. This study comprises more than 900 protein identifications, including numerous integral membrane proteins, and among these 185 differential expressions. Surprisingly, unregulated catalase and no elevated H(2)O(2) levels demonstrate that no oxidative stress occurs after treatment with the iron-containing compound as a consequence of the potential Fenton reaction. A sufficient iron supply is evidenced by the iron-containing protein aconitase and SufB (the latter belongs to an iron-sulfur cluster assembly system) and decreased levels of ATP-binding-cassette-type cobalamin/Fe(3+) siderophore transporters. The organometallic peptide antibiotic targets the cell membrane, which is evident by decreased levels of various integral membrane proteins, such as peptide permeases and transporters, and an altered lipid composition. Conversion to a more rigid cell membrane seems to be a relevant protective strategy of C. glutamicum against the ferrocene-conjugated antimicrobial peptide compound.
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Oveisi H, Rahighi S, Jiang X, Nemoto Y, Beitollahi A, Wakatsuki S, Yamauchi Y. Unusual Antibacterial Property of Mesoporous Titania Films: Drastic Improvement by Controlling Surface Area and Crystallinity. Chem Asian J 2010; 5:1978-83. [DOI: 10.1002/asia.201000351] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Kumar D, Joshi S, Rohilla RK, Roy N, Rawat DS. Synthesis and antibacterial activity of benzyl-[3-(benzylamino-methyl)-cyclohexylmethyl]-amine derivatives. Bioorg Med Chem Lett 2010; 20:893-5. [DOI: 10.1016/j.bmcl.2009.12.074] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2009] [Revised: 12/15/2009] [Accepted: 12/17/2009] [Indexed: 10/20/2022]
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Zhou ZX, Wei DF, Guan Y, Zheng AN, Zhong JJ. Damage of Escherichia coli membrane by bactericidal agent polyhexamethylene guanidine hydrochloride: micrographic evidences. J Appl Microbiol 2009; 108:898-907. [PMID: 19709338 DOI: 10.1111/j.1365-2672.2009.04482.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS The purpose of this study was to provide micrographic evidences for the damaged membrane structure and intracellular structure change of Escherichia coli strain 8099, induced by polyhexamethylene guanidine hydrochloride (PHMG). METHODS AND RESULTS The bactericidal effect of PHMG on E. coli was investigated based on beta-galactosidase activity assay, fluorescein-5-isothiocyanate confocal laser scanning microscopy, field emission scanning electron microscopy and transmission electron microscopy. The results revealed that a low dose (13 microg ml(-1)) of PHMG slightly damaged the outer membrane structure of the treated bacteria and increased the permeability of the cytoplasmic membrane, while no significant damage was observed to the morphological structure of the cells. A high dose (23 microg ml(-1)) of PHMG collapsed the outer membrane structure, led to the formation of a local membrane pore across the membrane and badly damaged the internal structure of the cells. Subsequently, intracellular components were leaked followed by cell inactivation. CONCLUSIONS Dose-dependent membrane disruption was the main bactericidal mechanism of PHMG. The formation of the local membrane pores was probable after exposure to a high dose (23 microg ml(-1)) of PHMG. Micrographic evidences were provided about the damaged membrane structure and intracellular structure change of E. coli. SIGNIFICANCE AND IMPACT OF THE STUDY The presented information helps understand the bactericidal mechanism of PHMG by membrane damage.
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Affiliation(s)
- Z X Zhou
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai, China
| | - D F Wei
- Key Laboratory for Ultrafine Materials, Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai, China
| | - Y Guan
- Key Laboratory for Ultrafine Materials, Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai, China
| | - A N Zheng
- Key Laboratory for Ultrafine Materials, Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai, China
| | - J J Zhong
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai, China., Key Laboratory of Microbial Metabolism, Ministry of Education, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
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Minond D, Saldanha SA, Subramaniam P, Spaargaren M, Spicer T, Fotsing JR, Weide T, Fokin VV, Sharpless KB, Galleni M, Bebrone C, Lassaux P, Hodder P. Inhibitors of VIM-2 by screening pharmacologically active and click-chemistry compound libraries. Bioorg Med Chem 2009; 17:5027-37. [PMID: 19553129 DOI: 10.1016/j.bmc.2009.05.070] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2009] [Revised: 05/22/2009] [Accepted: 05/27/2009] [Indexed: 12/27/2022]
Abstract
VIM-2 is an Ambler class B metallo-beta-lactamase (MBL) capable of hydrolyzing a broad-spectrum of beta-lactam antibiotics. Although the discovery and development of MBL inhibitors continue to be an area of active research, an array of potent, small molecule inhibitors is yet to be fully characterized for VIM-2. In the presented research, a compound library screening approach was used to identify and characterize VIM-2 inhibitors from a library of pharmacologically active compounds as well as a focused 'click' chemistry library. The four most potent VIM-2 inhibitors resulting from a VIM-2 screen were characterized by kinetic studies in order to determine K(i) and mechanism of enzyme inhibition. As a result, two previously described pharmacologic agents, mitoxantrone (1,4-dihydroxy-5,8-bis([2-([2-hydroxyethyl]amino)ethyl]amino)-9,10-anthracenedione) and 4-chloromercuribenzoic acid (pCMB) were found to be active, the former as a non-competitive inhibitor (K(i)=K(i)(')=1.5+/-0.2microM) and the latter as a slowly reversible or irreversible inhibitor. Additionally, two novel sulfonyl-triazole analogs from the click library were identified as potent, competitive VIM-2 inhibitors: N-((4-((but-3-ynyloxy)methyl)-1H-1,2,3-triazol-5-yl)methyl)-4-iodobenzenesulfonamide (1, K(i)=0.41+/-0.03microM) and 4-iodo-N-((4-(methoxymethyl)-1H-1,2,3-triazol-5-yl)methyl)benzenesulfonamide (2, K(i)=1.4+/-0.10microM). Mitoxantrone and pCMB were also found to potentiate imipenem efficacy in MIC and synergy assays employing Escherichia coli. Taken together, all four compounds represent useful chemical probes to further investigate mechanisms of VIM-2 inhibition in biochemical and microbiology-based assays.
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Affiliation(s)
- Dmitriy Minond
- Lead Identification, Translational Research Institute, The Scripps Research Institute, Scripps Florida, 130 Scripps Way #1A1, Jupiter, 33458 FL, USA
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Vijayalakshmi S, Ramasamy MS, Murugesh S, Murugan A. Isolation and screening of marine associated bacteria from Tamil Nadu, Southeast coast of India for potential antibacterial activity. ANN MICROBIOL 2008. [DOI: 10.1007/bf03175564] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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38
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Breault GA, Comita-Prevoir J, Eyermann CJ, Geng B, Petrichko R, Doig P, Gorseth E, Noonan B. Exploring 8-benzyl pteridine-6,7-diones as inhibitors of glutamate racemase (MurI) in Gram-positive bacteria. Bioorg Med Chem Lett 2008; 18:6100-3. [DOI: 10.1016/j.bmcl.2008.10.022] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2008] [Accepted: 10/06/2008] [Indexed: 11/16/2022]
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39
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Smart DJ. Genotoxicity of topoisomerase II inhibitors: An anti-infective perspective. Toxicology 2008; 254:192-8. [DOI: 10.1016/j.tox.2008.08.023] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2008] [Revised: 08/19/2008] [Accepted: 08/29/2008] [Indexed: 11/17/2022]
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Hanselmann R, Johnson G, Reeve MM, Huang ST. Identification and Suppression of a Dimer Impurity in the Development of Delafloxacin. Org Process Res Dev 2008. [DOI: 10.1021/op800238q] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Roger Hanselmann
- Rib-X Pharmaceuticals, Inc., 300 George Street, Suite 301, New Haven, Connecticut, 06511, U.S.A., and ScinoPharm Taiwan, Ltd., No.1, Nan-Ke 8th Road, Tainan Science-Based Industrial Park, Shan-Hua, Tainan County, 74144 Taiwan, R.O.C
| | - Graham Johnson
- Rib-X Pharmaceuticals, Inc., 300 George Street, Suite 301, New Haven, Connecticut, 06511, U.S.A., and ScinoPharm Taiwan, Ltd., No.1, Nan-Ke 8th Road, Tainan Science-Based Industrial Park, Shan-Hua, Tainan County, 74144 Taiwan, R.O.C
| | - Maxwell M. Reeve
- Rib-X Pharmaceuticals, Inc., 300 George Street, Suite 301, New Haven, Connecticut, 06511, U.S.A., and ScinoPharm Taiwan, Ltd., No.1, Nan-Ke 8th Road, Tainan Science-Based Industrial Park, Shan-Hua, Tainan County, 74144 Taiwan, R.O.C
| | - Shu-Ting Huang
- Rib-X Pharmaceuticals, Inc., 300 George Street, Suite 301, New Haven, Connecticut, 06511, U.S.A., and ScinoPharm Taiwan, Ltd., No.1, Nan-Ke 8th Road, Tainan Science-Based Industrial Park, Shan-Hua, Tainan County, 74144 Taiwan, R.O.C
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41
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Rotem S, Mor A. Antimicrobial peptide mimics for improved therapeutic properties. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1788:1582-92. [PMID: 19028449 DOI: 10.1016/j.bbamem.2008.10.020] [Citation(s) in RCA: 203] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2008] [Revised: 10/16/2008] [Accepted: 10/21/2008] [Indexed: 01/04/2023]
Abstract
The relatively recent recognition of the major role played by antimicrobial peptides (AMPs) in sustaining an effective host response to immune challenges was greatly influenced by studies of amphibian peptides. AMPs are also widely regarded as a potential source of future antibiotics owing to a remarkable set of advantageous properties ranging from molecular simplicity to low-resistance swift-kill of a broad range of microbial cells. However, the peptide formula per se, represents less than ideal drug candidates, namely because of poor bioavailability issues, potential immunogenicity, optional toxicity and high production costs. To address these issues, synthetic peptides have been designed, reproducing the critical peptide biophysical characteristic in unnatural sequence-specific oligomers. Thus, the use of peptidomimetics to overcome the limitations inherent to peptides physical characteristics is becoming an important and promising approach for improving the therapeutic potential of AMPs. Here, we review most recent advances in the design strategies and the biophysical properties of the main classes of mimics to natural AMPs, emphasizing the importance of structure-activity relationship studies in fine-tuning of their physicochemical attributes for improved antimicrobial properties.
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Affiliation(s)
- Shahar Rotem
- Department of Biotechnology and Food Engineering, Technion - Israel Institute of Technology, Israel
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42
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Exploring 9-benzyl purines as inhibitors of glutamate racemase (MurI) in Gram-positive bacteria. Bioorg Med Chem Lett 2008; 18:4368-72. [DOI: 10.1016/j.bmcl.2008.06.068] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2008] [Revised: 06/18/2008] [Accepted: 06/19/2008] [Indexed: 11/19/2022]
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43
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Radzishevsky IS, Kovachi T, Porat Y, Ziserman L, Zaknoon F, Danino D, Mor A. Structure-activity relationships of antibacterial acyl-lysine oligomers. ACTA ACUST UNITED AC 2008; 15:354-62. [PMID: 18420142 DOI: 10.1016/j.chembiol.2008.03.006] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2007] [Revised: 02/21/2008] [Accepted: 03/10/2008] [Indexed: 01/08/2023]
Abstract
We describe structure-activity relationships that emerged from biophysical data obtained with a library of antimicrobial peptide mimetics composed of 103 oligoacyllysines (OAKs) designed to pin down the importance of hydrophobicity (H) and charge (Q). Based on results obtained with OAKs displaying minimal inhibitory concentration < or = 3 microM, the data indicate that potent inhibitory activity of the gram-negative Escherichia coli and the gram-positive Staphylococcus aureus required a relatively narrow yet distinct window of HQ values where the acyl length played multiple and critical roles, both in molecular organization and in selective activity. Thus, incorporation of long-but not short-acyl chains within a peptide backbone is shown to lead to rigid supramolecular organization responsible for poor antibacterial activity and enhanced hemolytic activity. However, sequence manipulations, including introduction of a tandem lysine motif into the oligomer backbone, enabled disassembly of aggregated OAKs and subsequently revealed tiny, nonhemolytic, yet potent antibacterial derivatives.
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Affiliation(s)
- Inna S Radzishevsky
- Department of Biotechnology & Food Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel
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Chopra I, Schofield C, Everett M, O'Neill A, Miller K, Wilcox M, Frère JM, Dawson M, Czaplewski L, Urleb U, Courvalin P. Treatment of health-care-associated infections caused by Gram-negative bacteria: a consensus statement. THE LANCET. INFECTIOUS DISEASES 2008; 8:133-9. [PMID: 18222164 DOI: 10.1016/s1473-3099(08)70018-5] [Citation(s) in RCA: 168] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This consensus statement presents the conclusions of a group of academic and industrial experts who met in London in September, 2006, to consider the issues associated with the treatment of hospital infections caused by Gram-negative bacteria. The group discussed the severe clinical problems arising from the emergence of antibiotic resistance in these bacteria and the lack of new antibacterial agents to challenge the threat. The discovery of new drugs active against hospital-acquired Gram-negative bacteria is essential to prevent a future medical and social catastrophe. An important strategy to promote drug discovery will be the development of focused cooperations between academic institutions and small pharmaceutical companies.
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Affiliation(s)
- Ian Chopra
- Antimicrobial Research Centre and Research Institute of Molecular and Cellular Biology, University of Leeds, Leeds, UK.
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Abstract
Bacterial populations produce a small number of dormant persister cells that exhibit multidrug tolerance. All resistance mechanisms do essentially the same thing: prevent the antibiotic from hitting a target. By contrast, tolerance apparently works by shutting down the targets. Bactericidal antibiotics kill bacteria by corrupting their targets, rather than merely inhibiting them. Shutting down the targets then protects from killing. The number of persisters in a growing population of bacteria rises at mid-log and reaches a maximum of approximately 1% at stationary state. Similarly, slow-growing biofilms produce substantial numbers of persisters. The ability of a biofilm to limit the access of the immune system components, and the ability of persisters to sustain an antibiotic attack could then account for the recalcitrance of such infections in vivo and for their relapsing nature. Isolation of Escherichia coli persisters by lysing a population or by sorting GFP-expressing cells with diminished translation allowed to obtain a gene expression profile. The profile indicated downregulated biosynthetic pathways, consistent with their dormant nature, and indicated overexpression of toxin/antitoxin (TA) modules. Stochastic overexpression of toxins that inhibit essential functions such as translation may contribute to persister formation. Ectopic expression of RelE, MazF, and HipA toxins produced multidrug tolerant cells. Apart from TA modules, glpD and plsB were identified as potential persister genes by overexpression cloning of a genomic library and selection for antibiotic tolerance. Yeast Candida albicans forms recalcitrant biofilm infections that are tolerant to antibiotics, similarly to bacterial biofilms. C. albicans biofilms produce multidrug tolerant persisters that are not mutants, but rather phenotypic variants of the wild type. Unlike bacterial persisters, however, C. albicans persisters were only observed in a biofilm, but not in a planktonic stationary population. Identification of persister genes opens the way to a rational design of anti-biofilm therapy. Combination of a conventional antibiotic with a compound inhibiting persister formation or maintenance may produce an effective therapeutic. Other approaches to the problem include sterile-surface materials, prodrug antibiotics, and cyclical application of conventional antimicrobials.
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Lerner CG, Hajduk PJ, Wagner R, Wagenaar FL, Woodall C, Gu YG, Searle XB, Florjancic AS, Zhang T, Clark RF, Cooper CS, Mack JC, Yu L, Cai M, Betz SF, Chovan LE, McCall JO, Black-Schaefer CL, Kakavas SJ, Schurdak ME, Comess KM, Walter KA, Edalji R, Dorwin SA, Smith RA, Hebert EJ, Harlan JE, Metzger RE, Merta PJ, Baranowski JL, Coen ML, Thornewell SJ, Shivakumar AG, Saiki AY, Soni N, Bui M, Balli DJ, Sanders WJ, Nilius AM, Holzman TF, Fesik SW, Beutel BA. From Bacterial Genomes to Novel Antibacterial Agents: Discovery, Characterization, and Antibacterial Activity of Compounds that Bind to HI0065 (YjeE) from Haemophilus influenzae. Chem Biol Drug Des 2007; 69:395-404. [PMID: 17581233 DOI: 10.1111/j.1747-0285.2007.00521.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
As part of a fully integrated and comprehensive strategy to discover novel antibacterial agents, NMR- and mass spectrometry-based affinity selection screens were performed to identify compounds that bind to protein targets uniquely found in bacteria and encoded by genes essential for microbial viability. A biphenyl acid lead series emerged from an NMR-based screen with the Haemophilus influenzae protein HI0065, a member of a family of probable ATP-binding proteins found exclusively in eubacteria. The structure-activity relationships developed around the NMR-derived biphenyl acid lead were consistent with on-target antibacterial activity as the Staphylococcus aureus antibacterial activity of the series correlated extremely well with binding affinity to HI0065, while the correlation of binding affinity with B-cell cytotoxicity was relatively poor. Although further studies are needed to conclusively establish the mode of action of the biphenyl series, these compounds represent novel leads that can serve as the basis for the development of novel antibacterial agents that appear to work via an unprecedented mechanism of action. Overall, these results support the genomics-driven hypothesis that targeting bacterial essential gene products that are not present in eukaryotic cells can identify novel antibacterial agents.
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Affiliation(s)
- Claude G Lerner
- Abbott Global Pharmaceutical Research and Development, Abbott Park, IL 60064-6098, USA
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Ochsner UA, Sun X, Jarvis T, Critchley I, Janjic N. Aminoacyl-tRNA synthetases: essential and still promising targets for new anti-infective agents. Expert Opin Investig Drugs 2007; 16:573-93. [PMID: 17461733 DOI: 10.1517/13543784.16.5.573] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The emergence of resistance to existing antibiotics demands the development of novel antimicrobial agents directed against novel targets. Historically, bacterial cell wall synthesis, protein, and DNA and RNA synthesis have been major targets of very successful classes of antibiotics such as beta-lactams, glycopeptides, macrolides, aminoglycosides, tetracyclines, rifampicins and quinolones. Recently, efforts have been made to develop novel agents against validated targets in these pathways but also against new, previously unexploited targets. The era of genomics has provided insights into novel targets in microbial pathogens. Among the less exploited--but still promising--targets is the family of 20 aminoacyl-tRNA synthetases (aaRSs), which are essential for protein synthesis. These targets have been validated in nature as aaRS inhibition has been shown as the specific mode of action for many natural antimicrobial agents synthesized by bacteria and fungi. Therefore, aaRSs have the potential to be targeted by novel agents either from synthetic or natural sources to yield specific and selective anti-infectives. Numerous high-throughput screening programs aimed at identifying aaRS inhibitors have been performed over the last 20 years. A large number of promising lead compounds have been identified but only a few agents have moved forward into clinical development. This review provides an update on the present strategies to develop novel aaRS inhibitors as anti-infective drugs.
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Affiliation(s)
- Urs A Ochsner
- Replidyne, Inc., 1450 Infinite Dr, Louisville, CO 80027, USA.
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Brandi L, Fabbretti A, Milon P, Carotti M, Pon CL, Gualerzi CO. Methods for identifying compounds that specifically target translation. Methods Enzymol 2007; 431:229-67. [PMID: 17923238 DOI: 10.1016/s0076-6879(07)31012-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
This chapter presents methods and protocols suitable for the identification and characterization of inhibitors of the prokaryotic and/or eukaryotic translational apparatus as a whole or targeting specific, underexploited targets of the bacterial protein synthetic machinery such as translation initiation and aminoacylation. Some of the methods described have been used successfully for the high-throughput screening of libraries of natural or synthetic compounds and make use of model "universal" mRNAs that can be translated with similar efficiency by cellfree extracts of bacterial, yeast, and HeLa cells. Other methods presented here are suitable for secondary screening tests aimed at identifying a specific target of an antibiotic within the translational pathway of prokaryotic cells.
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49
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Foleno BD, Abbanat D, Goldschmidt RM, Flamm RK, Paget SD, Webb GC, Wira E, Macielag MJ, Bush K. In vitro antibacterial activity of the pyrrolopyrazolyl-substituted oxazolidinone RWJ-416457. Antimicrob Agents Chemother 2006; 51:361-5. [PMID: 17101672 PMCID: PMC1797661 DOI: 10.1128/aac.01017-06] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
RWJ-416457, an investigational pyrrolopyrazolyl-substituted oxazolidinone, inhibited the growth of linezolid-susceptible staphylococci, enterococci, and streptococci at concentrations of < or =4 microg/ml, generally exhibiting two- to fourfold-greater potency than that of linezolid. Time-kill studies demonstrated bacteriostatic effects for both RWJ-416457 and linezolid.
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Affiliation(s)
- Barbara D Foleno
- Johnson and Johnson Pharmaceutical Research and Development, L.L.C., Raritan, NJ 08869, USA.
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50
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Fernandez J. In vivo animal models: quantitative models used for identifying antibacterial agents. CURRENT PROTOCOLS IN PHARMACOLOGY 2006; Chapter 13:Unit13A.5. [PMID: 22294173 DOI: 10.1002/0471141755.ph13a05s34] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Determining the in vivo bactericidal potential of novel agents is critical for selecting drug candidates. Described in this unit are two protocols that measure the amount of bacterial killing under very different conditions. The mouse pouch protocol is a rapid assay that provides efficacy data in an acute infection, whereas the rabbit tissue cage protocol assesses the ability of a compound to eradicate bacteria in a chronic abscess infection. Data from these tests, along with those from other qualitative and quantitative assays, are important for defining antibacterial efficacy in vivo.
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Affiliation(s)
- Jeffrey Fernandez
- Johnson & Johnson Pharmaceutical Research and Development, L.L.C., Raritan, New Jersey, USA
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