1351
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Putative histidine kinase inhibitors with antibacterial effect against multi-drug resistant clinical isolates identified by in vitro and in silico screens. Sci Rep 2016; 6:26085. [PMID: 27173778 PMCID: PMC4865847 DOI: 10.1038/srep26085] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 03/15/2016] [Indexed: 01/21/2023] Open
Abstract
Novel antibacterials are urgently needed to address the growing problem of bacterial resistance to conventional antibiotics. Two-component systems (TCS) are widely used by bacteria to regulate gene expression in response to various environmental stimuli and physiological stress and have been previously proposed as promising antibacterial targets. TCS consist of a sensor histidine kinase (HK) and an effector response regulator. The HK component contains a highly conserved ATP-binding site that is considered to be a promising target for broad-spectrum antibacterial drugs. Here, we describe the identification of putative HK autophosphorylation inhibitors following two independent experimental approaches: in vitro fragment-based screen via differential scanning fluorimetry and in silico structure-based screening, each followed up by the exploration of analogue compounds as identified by ligand-based similarity searches. Nine of the tested compounds showed antibacterial effect against multi-drug resistant clinical isolates of bacterial pathogens and include three novel scaffolds, which have not been explored so far in other antibacterial compounds. Overall, putative HK autophosphorylation inhibitors were found that together provide a promising starting point for further optimization as antibacterials.
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1352
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Abstract
After 50 years drought, several drugs are looming from the pipeline to combat tuberculosis. They will serve as a boon to the field that has been burdened with primitive, inadequate treatments and drug-resistant bacterial strains. From the decades, due to lack of interest and resources, the field has suffered a lot. Learning from the flaws, scientists have renovated their approaches to the finding of new antitubercular drugs. The first line drugs take about six months or more for the entire treatment. The second line remedy for resistant-tuberculosis requires daily injections which carry severe side effects. Drug resistance remains a constant menace because patients stop the medication once they start feeling better. So new drugs are required to be explored which are effective against tuberculosis especially drug resistant tuberculosis. These drugs need to work well with other drugs as well as with antivirals used for the treatment of human immunodeficiency virus. It is also very important to be considered that the treatments need to be cheap, as tuberculosis primarily affects people more in the developing countries. Further, new drugs must cure the disease in short span of time than the current six to nine month regimen. Recently a few new and potent drugs such as bedaquiline, delamanid, teixobactin have been evolved which may serve as a nice step forward, with a better outcome. Teixobactin, a new antibiotic has been found to have promising action against resistant strains, is also under consideration.
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Affiliation(s)
- Tejal Rawal
- Institute of Pharmacy, Nirma University, S. G. Highway, Ahmedabad-382 481, India
| | - Shital Butani
- Institute of Pharmacy, Nirma University, S. G. Highway, Ahmedabad-382 481, India
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1353
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Gerits E, Blommaert E, Lippell A, O’Neill AJ, Weytjens B, De Maeyer D, Fierro AC, Marchal K, Marchand A, Chaltin P, Spincemaille P, De Brucker K, Thevissen K, Cammue BPA, Swings T, Liebens V, Fauvart M, Verstraeten N, Michiels J. Elucidation of the Mode of Action of a New Antibacterial Compound Active against Staphylococcus aureus and Pseudomonas aeruginosa. PLoS One 2016; 11:e0155139. [PMID: 27167126 PMCID: PMC4864301 DOI: 10.1371/journal.pone.0155139] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 04/25/2016] [Indexed: 01/29/2023] Open
Abstract
Nosocomial and community-acquired infections caused by multidrug resistant bacteria represent a major human health problem. Thus, there is an urgent need for the development of antibiotics with new modes of action. In this study, we investigated the antibacterial characteristics and mode of action of a new antimicrobial compound, SPI031 (N-alkylated 3, 6-dihalogenocarbazol 1-(sec-butylamino)-3-(3,6-dichloro-9H-carbazol-9-yl)propan-2-ol), which was previously identified in our group. This compound exhibits broad-spectrum antibacterial activity, including activity against the human pathogens Staphylococcus aureus and Pseudomonas aeruginosa. We found that SPI031 has rapid bactericidal activity (7-log reduction within 30 min at 4x MIC) and that the frequency of resistance development against SPI031 is low. To elucidate the mode of action of SPI031, we performed a macromolecular synthesis assay, which showed that SPI031 causes non-specific inhibition of macromolecular biosynthesis pathways. Liposome leakage and membrane permeability studies revealed that SPI031 rapidly exerts membrane damage, which is likely the primary cause of its antibacterial activity. These findings were supported by a mutational analysis of SPI031-resistant mutants, a transcriptome analysis and the identification of transposon mutants with altered sensitivity to the compound. In conclusion, our results show that SPI031 exerts its antimicrobial activity by causing membrane damage, making it an interesting starting point for the development of new antibacterial therapies.
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Affiliation(s)
- Evelien Gerits
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
| | - Eline Blommaert
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
| | - Anna Lippell
- School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
| | - Alex J. O’Neill
- School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
| | - Bram Weytjens
- Department of Information Technology (INTEC, iMINDS), U.Ghent, Ghent, Belgium
| | - Dries De Maeyer
- Department of Information Technology (INTEC, iMINDS), U.Ghent, Ghent, Belgium
| | - Ana Carolina Fierro
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
- Department of Information Technology (INTEC, iMINDS), U.Ghent, Ghent, Belgium
| | - Kathleen Marchal
- Department of Information Technology (INTEC, iMINDS), U.Ghent, Ghent, Belgium
- Department of Plant Biotechnology and Bioinformatics, U.Ghent, Ghent, Belgium
| | - Arnaud Marchand
- CISTIM Leuven vzw, Bio-Incubator, KU Leuven, Leuven, Belgium
| | - Patrick Chaltin
- CISTIM Leuven vzw, Bio-Incubator, KU Leuven, Leuven, Belgium
- Centre for Drug Design and Discovery (CD3), Research and Development, KU Leuven, Leuven, Belgium
| | - Pieter Spincemaille
- Department of Laboratory Medicine, University Hospitals Leuven, Leuven, Belgium
| | | | - Karin Thevissen
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
| | - Bruno P. A. Cammue
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
- Department of Plant Systems Biology, VIB, Ghent, Belgium
| | - Toon Swings
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
| | - Veerle Liebens
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
| | - Maarten Fauvart
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
- imec, Smart Systems and Emerging Technologies Unit, Department of Life Science Technologies, Leuven, Belgium
| | | | - Jan Michiels
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
- * E-mail:
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1354
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Rios AC, Moutinho CG, Pinto FC, Del Fiol FS, Jozala A, Chaud MV, Vila MMDC, Teixeira JA, Balcão VM. Alternatives to overcoming bacterial resistances: State-of-the-art. Microbiol Res 2016; 191:51-80. [PMID: 27524653 DOI: 10.1016/j.micres.2016.04.008] [Citation(s) in RCA: 156] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 03/28/2016] [Accepted: 04/21/2016] [Indexed: 12/23/2022]
Abstract
Worldwide, bacterial resistance to chemical antibiotics has reached such a high level that endangers public health. Presently, the adoption of alternative strategies that promote the elimination of resistant microbial strains from the environment is of utmost importance. This review discusses and analyses several (potential) alternative strategies to current chemical antibiotics. Bacteriophage (or phage) therapy, although not new, makes use of strictly lytic phage particles as an alternative, or a complement, in the antimicrobial treatment of bacterial infections. It is being rediscovered as a safe method, because these biological entities devoid of any metabolic machinery do not possess any affinity whatsoever to eukaryotic cells. Lysin therapy is also recognized as an innovative antimicrobial therapeutic option, since the topical administration of preparations containing purified recombinant lysins with amounts in the order of nanograms, in infections caused by Gram-positive bacteria, demonstrated a high therapeutic potential by causing immediate lysis of the target bacterial cells. Additionally, this therapy exhibits the potential to act synergistically when combined with certain chemical antibiotics already available on the market. Another potential alternative antimicrobial therapy is based on the use of antimicrobial peptides (AMPs), amphiphilic polypeptides that cause disruption of the bacterial membrane and can be used in the treatment of bacterial, fungal and viral infections, in the prevention of biofilm formation, and as antitumoral agents. Interestingly, bacteriocins are a common strategy of bacterial defense against other bacterial agents, eliminating the potential opponents of the former and increasing the number of available nutrients in the environment for their own growth. They can be applied in the food industry as biopreservatives and as probiotics, and also in fighting multi-resistant bacterial strains. The use of antibacterial antibodies promises to be extremely safe and effective. Additionally, vaccination emerges as one of the most promising preventive strategies. All these will be tackled in detail in this review paper.
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Affiliation(s)
- Alessandra C Rios
- LaBNUS-Biomaterials and Nanotechnology Laboratory, i(bs)2i(bs)(2)-intelligent biosensing and biomolecule stabilization research group, University of Sorocaba, Sorocaba/SP, Brazil
| | - Carla G Moutinho
- CEB-Centre of Biological Engineering, University of Minho, Braga, Portugal; University Fernando Pessoa, Porto, Portugal
| | | | - Fernando S Del Fiol
- LaBNUS-Biomaterials and Nanotechnology Laboratory, i(bs)2i(bs)(2)-intelligent biosensing and biomolecule stabilization research group, University of Sorocaba, Sorocaba/SP, Brazil
| | - Angela Jozala
- LaBNUS-Biomaterials and Nanotechnology Laboratory, i(bs)2i(bs)(2)-intelligent biosensing and biomolecule stabilization research group, University of Sorocaba, Sorocaba/SP, Brazil
| | - Marco V Chaud
- LaBNUS-Biomaterials and Nanotechnology Laboratory, i(bs)2i(bs)(2)-intelligent biosensing and biomolecule stabilization research group, University of Sorocaba, Sorocaba/SP, Brazil
| | - Marta M D C Vila
- LaBNUS-Biomaterials and Nanotechnology Laboratory, i(bs)2i(bs)(2)-intelligent biosensing and biomolecule stabilization research group, University of Sorocaba, Sorocaba/SP, Brazil
| | - José A Teixeira
- CEB-Centre of Biological Engineering, University of Minho, Braga, Portugal
| | - Victor M Balcão
- LaBNUS-Biomaterials and Nanotechnology Laboratory, i(bs)2i(bs)(2)-intelligent biosensing and biomolecule stabilization research group, University of Sorocaba, Sorocaba/SP, Brazil; CEB-Centre of Biological Engineering, University of Minho, Braga, Portugal.
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1355
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Du J, Singh H, Yi TH. Biosynthesis of silver nanoparticles by Novosphingobium sp. THG-C3 and their antimicrobial potential. ARTIFICIAL CELLS NANOMEDICINE AND BIOTECHNOLOGY 2016; 45:211-217. [PMID: 27145847 DOI: 10.1080/21691401.2016.1178135] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The present study described biosynthesis of silver nanoparticles (AgNPs) using a bacterial strain Novosphingobium sp. THG-C3, isolated from soil, and their application in antibacterial activity. The maximum absorbance values of the synthesized AgNPs was measured at 406 nm in ultraviolet-visible spectrophotometry and were mostly spherical in shape with particle size in range of 8-25 nm by field emission transmission electron microscopy analysis. X-ray diffraction pattern corresponding to planes (111), (200), (220), and (311) demonstrated the crystalline nature of the AgNPs. The synthesized AgNPs exhibited antimicrobial activity against various pathogens inculding Staphylococcus aureus, Candida tropicalis, Pseudomonas aeruginosa, Escherichia coli, Vibrio parahaemolyticus, Candida albicans, Salmonella enterica, Bacillus subtilis, and Bacillus cereus. In addition, the AgNPs in combination with commercial antibiotics enhanced antimicrobial activity against P. aeruginosa, S. enterica, E. coli, and V. parahaemolyticus. The AgNPs synthesized by strain Novosphingobium sp. THG-C3 are comparatively simple, green, cost-effective, and may serve as a potential antimicrobial agent.
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Affiliation(s)
- Juan Du
- a Department of Oriental Medicinal Biotechnology, College of Life Science , Kyung Hee University - Global Campus , Yongin-Si , Republic of Korea
| | - Hina Singh
- a Department of Oriental Medicinal Biotechnology, College of Life Science , Kyung Hee University - Global Campus , Yongin-Si , Republic of Korea
| | - Tae-Hoo Yi
- a Department of Oriental Medicinal Biotechnology, College of Life Science , Kyung Hee University - Global Campus , Yongin-Si , Republic of Korea
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1356
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Ma Z, Kim D, Adesogan AT, Ko S, Galvao K, Jeong KC. Chitosan Microparticles Exert Broad-Spectrum Antimicrobial Activity against Antibiotic-Resistant Micro-organisms without Increasing Resistance. ACS APPLIED MATERIALS & INTERFACES 2016; 8:10700-10709. [PMID: 27057922 DOI: 10.1021/acsami.6b00894] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Antibiotic resistance is growing exponentially, increasing public health concerns for humans and animals. In the current study, we investigated the antimicrobial features of chitosan microparticles (CM), engineered from chitosan by ion gelation, seeking potential application for treating infectious disease caused by multidrug resistant microorganisms. CM showed excellent antimicrobial activity against a wide range of microorganisms, including clinically important antibiotic-resistant pathogens without raising resistant mutants in serial passage assays over a period of 15 days, which is a significantly long passage compared to tested antibiotics used in human and veterinary medicine. In addition, CM treatment did not cause cross-resistance, which is frequently observed with other antibiotics and triggers multidrug resistance. Furthermore, CM activity was examined in simulated gastrointestinal fluids that CM encounter when orally administered. Antimicrobial activity of CM was exceptionally strong to eliminate pathogens completely. CM at a concentration of 0.1 μg/mL killed E. coli O157:H7 (5 × 10(8) CFU/mL) completely in synthetic gastric fluid within 20 min. Risk assessment of CM, in an in vitro animal model, revealed that CM did not disrupt the digestibility, pH or total volatile fatty acid production, indicating that CM likely do not affect the functionality of the rumen. Given all the advantages, CM can serve as a great candidate to treat infectious disease, especially those caused by antibiotic-resistant pathogens without adverse side effects.
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Affiliation(s)
- Zhengxin Ma
- Emerging Pathogens Institute, University of Florida , Gainesville, Florida 32611, United States
- Department of Animal Sciences, Institute of Food and Agricultural Sciences, University of Florida , Gainesville, Florida 32611, United States
| | - Donghyeon Kim
- Department of Animal Sciences, Institute of Food and Agricultural Sciences, University of Florida , Gainesville, Florida 32611, United States
- Division of Applied Life Science (BK21plus, Insti. of Agri. & Life Sci.), Gyeongsang National University , Jinju, South Korea
| | - Adegbola T Adesogan
- Department of Animal Sciences, Institute of Food and Agricultural Sciences, University of Florida , Gainesville, Florida 32611, United States
| | - Sanghoon Ko
- Department of Food Science and Technology, Sejong University , Seoul, South Korea
| | - Klibs Galvao
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida , Gainesville, Florida 32610, United States
- D. H. Barron Reproductive and Perinatal Biology Research Program, University of Florida , Gainesville, Florida 32610, United States
| | - Kwangcheol Casey Jeong
- Emerging Pathogens Institute, University of Florida , Gainesville, Florida 32611, United States
- Department of Animal Sciences, Institute of Food and Agricultural Sciences, University of Florida , Gainesville, Florida 32611, United States
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1357
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Indraningrat AAG, Smidt H, Sipkema D. Bioprospecting Sponge-Associated Microbes for Antimicrobial Compounds. Mar Drugs 2016; 14:E87. [PMID: 27144573 PMCID: PMC4882561 DOI: 10.3390/md14050087] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 04/15/2016] [Accepted: 04/26/2016] [Indexed: 12/17/2022] Open
Abstract
Sponges are the most prolific marine organisms with respect to their arsenal of bioactive compounds including antimicrobials. However, the majority of these substances are probably not produced by the sponge itself, but rather by bacteria or fungi that are associated with their host. This review for the first time provides a comprehensive overview of antimicrobial compounds that are known to be produced by sponge-associated microbes. We discuss the current state-of-the-art by grouping the bioactive compounds produced by sponge-associated microorganisms in four categories: antiviral, antibacterial, antifungal and antiprotozoal compounds. Based on in vitro activity tests, identified targets of potent antimicrobial substances derived from sponge-associated microbes include: human immunodeficiency virus 1 (HIV-1) (2-undecyl-4-quinolone, sorbicillactone A and chartarutine B); influenza A (H1N1) virus (truncateol M); nosocomial Gram positive bacteria (thiopeptide YM-266183, YM-266184, mayamycin and kocurin); Escherichia coli (sydonic acid), Chlamydia trachomatis (naphthacene glycoside SF2446A2); Plasmodium spp. (manzamine A and quinolone 1); Leishmania donovani (manzamine A and valinomycin); Trypanosoma brucei (valinomycin and staurosporine); Candida albicans and dermatophytic fungi (saadamycin, 5,7-dimethoxy-4-p-methoxylphenylcoumarin and YM-202204). Thirty-five bacterial and 12 fungal genera associated with sponges that produce antimicrobials were identified, with Streptomyces, Pseudovibrio, Bacillus, Aspergillus and Penicillium as the prominent producers of antimicrobial compounds. Furthemore culture-independent approaches to more comprehensively exploit the genetic richness of antimicrobial compound-producing pathways from sponge-associated bacteria are addressed.
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Affiliation(s)
- Anak Agung Gede Indraningrat
- Laboratory of Microbiology, Wageningen University, Dreijenplein 10, Wageningen 6703 HB, The Netherlands.
- Department of Biology, Faculty of Mathematics and Science Education, Institut Keguruan dan Ilmu Pendidikan Persatuan Guru Republik Indonesia (IKIP PGRI) Bali, Jl. Seroja Tonja, Denpasar 80238, Indonesia.
| | - Hauke Smidt
- Laboratory of Microbiology, Wageningen University, Dreijenplein 10, Wageningen 6703 HB, The Netherlands.
| | - Detmer Sipkema
- Laboratory of Microbiology, Wageningen University, Dreijenplein 10, Wageningen 6703 HB, The Netherlands.
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1358
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Gibb BC. Physics 3 – 0 Chemistry. Nat Chem 2016; 8:399-400. [DOI: 10.1038/nchem.2504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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1359
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Pascual J, García-López M, Bills GF, Genilloud O. Longimicrobium terrae gen. nov., sp. nov., an oligotrophic bacterium of the under-represented phylum Gemmatimonadetes isolated through a system of miniaturized diffusion chambers. Int J Syst Evol Microbiol 2016; 66:1976-1985. [DOI: 10.1099/ijsem.0.000974] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Javier Pascual
- Fundación MEDINA, Avenida del Conocimiento 3, Health Sciences Technology Park, 18016 Granada, Spain
| | - Marina García-López
- Fundación MEDINA, Avenida del Conocimiento 3, Health Sciences Technology Park, 18016 Granada, Spain
| | - Gerald F. Bills
- Fundación MEDINA, Avenida del Conocimiento 3, Health Sciences Technology Park, 18016 Granada, Spain
| | - Olga Genilloud
- Fundación MEDINA, Avenida del Conocimiento 3, Health Sciences Technology Park, 18016 Granada, Spain
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1360
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Brown ED, Wright GD. Antibacterial drug discovery in the resistance era. Nature 2016; 529:336-43. [PMID: 26791724 DOI: 10.1038/nature17042] [Citation(s) in RCA: 1373] [Impact Index Per Article: 171.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 11/16/2015] [Indexed: 01/07/2023]
Abstract
The looming antibiotic-resistance crisis has penetrated the consciousness of clinicians, researchers, policymakers, politicians and the public at large. The evolution and widespread distribution of antibiotic-resistance elements in bacterial pathogens has made diseases that were once easily treatable deadly again. Unfortunately, accompanying the rise in global resistance is a failure in antibacterial drug discovery. Lessons from the history of antibiotic discovery and fresh understanding of antibiotic action and the cell biology of microorganisms have the potential to deliver twenty-first century medicines that are able to control infection in the resistance era.
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Affiliation(s)
- Eric D Brown
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario L8S 4L8, Canada.,Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario L8S 4L8, Canada
| | - Gerard D Wright
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario L8S 4L8, Canada.,Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario L8S 4L8, Canada
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1361
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Javani S, Lorca R, Latorre A, Flors C, Cortajarena AL, Somoza Á. Antibacterial Activity of DNA-Stabilized Silver Nanoclusters Tuned by Oligonucleotide Sequence. ACS APPLIED MATERIALS & INTERFACES 2016; 8:10147-10154. [PMID: 27058628 DOI: 10.1021/acsami.6b00670] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Silver nanoclusters (AgNCs) stabilized by DNA are promising materials with tunable fluorescent properties, which have been employed in a plethora of sensing systems. In this report, we explore their antimicrobial properties in Gram-positive and Gram-negative bacteria. After testing 9 oligonucleotides with different sequence and length, we found that the antibacterial activity depends on the sequence of the oligonucleotide employed. The sequences tested yielded fluorescent AgNCs, which can be grouped in blue, yellow, and red emitters. Interestingly, blue emitters yielded poor antibacterial activity, whereas yellow and red emitters afforded an activity similar to silver nitrate. Furthermore, structural studies using circular dichroism indicate the formation of complexes with different stability and structure, which might be one of the factors that modulate their activity. Finally, we prepared a trimeric structure containing the sequence that afforded the best antimicrobial activity, which inhibited the growth of Gram-positive and negative bacteria in the submicromolar range.
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Affiliation(s)
- Siamak Javani
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA Nanociencia), & Nanobiotecnología (IMDEA-Nanociencia), Unidad Asociada al Centro Nacional de Biotecnología (CSIC) , 28049 Madrid, Spain
| | - Romina Lorca
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA Nanociencia), & Nanobiotecnología (IMDEA-Nanociencia), Unidad Asociada al Centro Nacional de Biotecnología (CSIC) , 28049 Madrid, Spain
| | - Alfonso Latorre
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA Nanociencia), & Nanobiotecnología (IMDEA-Nanociencia), Unidad Asociada al Centro Nacional de Biotecnología (CSIC) , 28049 Madrid, Spain
| | - Cristina Flors
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA Nanociencia), & Nanobiotecnología (IMDEA-Nanociencia), Unidad Asociada al Centro Nacional de Biotecnología (CSIC) , 28049 Madrid, Spain
| | - Aitziber L Cortajarena
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA Nanociencia), & Nanobiotecnología (IMDEA-Nanociencia), Unidad Asociada al Centro Nacional de Biotecnología (CSIC) , 28049 Madrid, Spain
| | - Álvaro Somoza
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA Nanociencia), & Nanobiotecnología (IMDEA-Nanociencia), Unidad Asociada al Centro Nacional de Biotecnología (CSIC) , 28049 Madrid, Spain
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1362
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Use of bacteriophage to target bacterial surface structures required for virulence: a systematic search for antibiotic alternatives. Curr Genet 2016; 62:753-757. [PMID: 27113766 DOI: 10.1007/s00294-016-0603-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 04/11/2016] [Indexed: 01/21/2023]
Abstract
Bacteriophages (phage) that infect pathogenic bacteria often attach to surface receptors that are coincidentally required for virulence. Receptor loss or modification through mutation renders mutants both attenuated and phage resistant. Such attenuated mutants frequently have no apparent laboratory growth defects, but in the host, they fail to exhibit properties needed to produce disease such as mucosal colonization or survival within professional phagocytic cells. The connection between attenuation and phage resistance has been exploited in experimental demonstrations of phage therapy. In such experiments, phage resistant mutants that arise naturally during therapy are inconsequential because of their attenuated status. A more contemporary approach to exploiting this connection involves identifying small effector molecules, identified in high-throughput screens, that inhibit one or more of the steps needed to produce a functioning phage receptor. Since such biosynthetic steps are unique to bacteria, inhibitors can be utilized therapeutically, in lieu of antibiotics. Also, since the inhibitor is specific to a particular bacterium or group of bacteria, no off-target resistance is generated in the host's commensal bacterial population. This brief review covers examples of how mutations that confer phage resistance produce attenuation, and how this coincidental relationship can be exploited in the search for the next generation of therapeutic agents for bacterial diseases.
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1363
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Dou JL, Jiang YW, Xie JQ, Zhang XG. New Is Old, and Old Is New: Recent Advances in Antibiotic-Based, Antibiotic-Free and Ethnomedical Treatments against Methicillin-Resistant Staphylococcus aureus Wound Infections. Int J Mol Sci 2016; 17:E617. [PMID: 27120596 PMCID: PMC4881443 DOI: 10.3390/ijms17050617] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 04/18/2016] [Accepted: 04/19/2016] [Indexed: 12/26/2022] Open
Abstract
Staphylococcus aureus is the most common pathogen of wound infections. Thus far, methicillin-resistant S. aureus (MRSA) has become the major causative agent in wound infections, especially for nosocomial infections. MRSA infections are seldom eradicated by routine antimicrobial therapies. More concerning, some strains have become resistant to the newest antibiotics of last resort. Furthermore, horizontal transfer of a polymyxin resistance gene, mcr-1, has been identified in Enterobacteriaceae, by which resistance to the last group of antibiotics will likely spread rapidly. The worst-case scenario, "a return to the pre-antibiotic era", is likely in sight. A perpetual goal for antibiotic research is the discovery of an antibiotic that lacks resistance potential, such as the recent discovery of teixobactin. However, when considering the issue from an ecological and evolutionary standpoint, it is evident that it is insufficient to solve the antibiotic dilemma through the use of antibiotics themselves. In this review, we summarized recent advances in antibiotic-based, antibiotic-free and ethnomedical treatments against MRSA wound infections to identify new clues to solve the antibiotic dilemma. One potential solution is to use ethnomedical drugs topically. Some ethnomedical drugs have been demonstrated to be effective antimicrobials against MRSA. A decline in antibiotic resistance can therefore be expected, as has been demonstrated when antibiotic-free treatments were used to limit the use of antibiotics. It is also anticipated that these drugs will have low resistance potential, although there is only minimal evidence to support this claim to date. More clinical trials and animal tests should be conducted on this topic.
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Affiliation(s)
- Jian-Lin Dou
- Institute of Pathogenic Biology, School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China.
| | - Yi-Wei Jiang
- Spinal Surgery Department, Affiliated Hospital of Gansu University of Chinese Medicines, Lanzhou 730020, China.
| | - Jun-Qiu Xie
- Institute of Pathogenic Biology, School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China.
| | - Xiao-Gang Zhang
- Spinal Surgery Department, Affiliated Hospital of Gansu University of Chinese Medicines, Lanzhou 730020, China.
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1364
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Pawlowski AC, Johnson JW, Wright GD. Evolving medicinal chemistry strategies in antibiotic discovery. Curr Opin Biotechnol 2016; 42:108-117. [PMID: 27116217 DOI: 10.1016/j.copbio.2016.04.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 04/03/2016] [Accepted: 04/05/2016] [Indexed: 10/21/2022]
Abstract
Chemical modification of synthetic or natural product antibiotic scaffolds to expand potency and spectrum and to bypass mechanisms of resistance has dominated antibiotic drug discovery and proven immensely successful. However, the inexorable evolution of drug resistance coupled with a drought in innovation in antibiotic discovery contribute to a dearth of new drugs entering to market. Better understanding of the physicochemical properties of antibiotic chemical space is required to inform new antibiotic discovery. Innovations such as the development of antibiotic adjuvants to preserve efficacy of existing drugs together with expanding antibiotic chemical diversity through synthetic biology or new techniques to mine antibiotic producing organisms, are required to bridge the growing gap between the need for new drugs and their discovery.
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Affiliation(s)
- Andrew C Pawlowski
- Michael G. DeGroote Institute for Infectious Disease Research and the Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Jarrod W Johnson
- Michael G. DeGroote Institute for Infectious Disease Research and the Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Gerard D Wright
- Michael G. DeGroote Institute for Infectious Disease Research and the Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada.
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1365
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Zhang Y, Poopari MR, Cai X, Savin A, Dezhahang Z, Cheramy J, Xu Y. IR and Vibrational Circular Dichroism Spectroscopy of Matrine- and Artemisinin-Type Herbal Products: Stereochemical Characterization and Solvent Effects. JOURNAL OF NATURAL PRODUCTS 2016; 79:1012-1023. [PMID: 27070079 DOI: 10.1021/acs.jnatprod.5b01082] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Five Chinese herbal medicines--matrine, oxymatrine, sophoridine, artemisinin, and dihydroartemisinin--were investigated using vibrational circular dichroism (VCD) experiments and density functional theory calculations to extract their stereochemical information. The three matrine-type alkaloids are available from the dry roots of Sophora flavescens and have long been used in various traditional Chinese herbal medicines to combat diseases such as cancer and cardiac arrhythmia. Artemisinin and the related dihydroartemisinin, discovered in 1979 by Professor Youyou Tu, a 2015 Nobel laureate in medicine, are effective drugs for the treatment of malaria. The VCD measurements were carried out in CDCl3 and DMSO-d6, two solvents with different dielectric constants and hydrogen-bonding characteristics. A "clusters-in-a-liquid" approach was used to model both explicit and implicit solvent effects. The studies show that effectively accounting for solvent effects is critical to using IR and VCD spectroscopy to provide unique spectroscopic features to differentiate the potential stereoisomers of these Chinese herbal medicines.
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Affiliation(s)
- Yuefei Zhang
- Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada , T6G 2G2
| | - M Reza Poopari
- Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada , T6G 2G2
| | - Xiaoli Cai
- Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada , T6G 2G2
| | - Aliaksandr Savin
- Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada , T6G 2G2
| | - Zahra Dezhahang
- Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada , T6G 2G2
| | - Joseph Cheramy
- Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada , T6G 2G2
| | - Yunjie Xu
- Department of Chemistry, University of Alberta , Edmonton, Alberta, Canada , T6G 2G2
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1366
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Discovery Strategies of Bioactive Compounds Synthesized by Nonribosomal Peptide Synthetases and Type-I Polyketide Synthases Derived from Marine Microbiomes. Mar Drugs 2016; 14:md14040080. [PMID: 27092515 PMCID: PMC4849084 DOI: 10.3390/md14040080] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 04/01/2016] [Accepted: 04/08/2016] [Indexed: 11/17/2022] Open
Abstract
Considering that 70% of our planet's surface is covered by oceans, it is likely that undiscovered biodiversity is still enormous. A large portion of marine biodiversity consists of microbiomes. They are very attractive targets of bioprospecting because they are able to produce a vast repertoire of secondary metabolites in order to adapt in diverse environments. In many cases secondary metabolites of pharmaceutical and biotechnological interest such as nonribosomal peptides (NRPs) and polyketides (PKs) are synthesized by multimodular enzymes named nonribosomal peptide synthetases (NRPSes) and type-I polyketide synthases (PKSes-I), respectively. Novel findings regarding the mechanisms underlying NRPS and PKS evolution demonstrate how microorganisms could leverage their metabolic potential. Moreover, these findings could facilitate synthetic biology approaches leading to novel bioactive compounds. Ongoing advances in bioinformatics and next-generation sequencing (NGS) technologies are driving the discovery of NRPs and PKs derived from marine microbiomes mainly through two strategies: genome-mining and metagenomics. Microbial genomes are now sequenced at an unprecedented rate and this vast quantity of biological information can be analyzed through genome mining in order to identify gene clusters encoding NRPSes and PKSes of interest. On the other hand, metagenomics is a fast-growing research field which directly studies microbial genomes and their products present in marine environments using culture-independent approaches. The aim of this review is to examine recent developments regarding discovery strategies of bioactive compounds synthesized by NRPS and type-I PKS derived from marine microbiomes and to highlight the vast diversity of NRPSes and PKSes present in marine environments by giving examples of recently discovered bioactive compounds.
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1367
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Wu J, Gao B, Zhu S. Single‐point mutation‐mediated local amphipathic adjustment dramatically enhances antibacterial activity of a fungal defensin. FASEB J 2016; 30:2602-14. [DOI: 10.1096/fj.201500157] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 03/28/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Jiajia Wu
- Group of Peptide Biology and Evolution, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of SciencesBeijingChina
| | - Bin Gao
- Group of Peptide Biology and Evolution, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of SciencesBeijingChina
| | - Shunyi Zhu
- Group of Peptide Biology and Evolution, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of SciencesBeijingChina
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1368
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Zutz C, Bacher M, Parich A, Kluger B, Gacek-Matthews A, Schuhmacher R, Wagner M, Rychli K, Strauss J. Valproic Acid Induces Antimicrobial Compound Production in Doratomyces microspores. Front Microbiol 2016; 7:510. [PMID: 27148199 PMCID: PMC4829596 DOI: 10.3389/fmicb.2016.00510] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 03/29/2016] [Indexed: 01/01/2023] Open
Abstract
One of the biggest challenges in public health is the rising number of antibiotic resistant pathogens and the lack of novel antibiotics. In recent years there is a rising focus on fungi as sources of antimicrobial compounds due to their ability to produce a large variety of bioactive compounds and the observation that virtually every fungus may still contain yet unknown so called “cryptic,” often silenced, compounds. These putative metabolites could include novel bioactive compounds. Considerable effort is spent on methods to induce production of these “cryptic” metabolites. One approach is the use of small molecule effectors, potentially influencing chromatin landscape in fungi. We observed that the supernatant of the fungus Doratomyces (D.) microsporus treated with valproic acid (VPA) displayed antimicrobial activity against Staphylococcus (S.) aureus and two methicillin resistant clinical S. aureus isolates. VPA treatment resulted in enhanced production of seven antimicrobial compounds: cyclo-(L-proline-L-methionine) (cPM), p-hydroxybenzaldehyde, cyclo-(phenylalanine-proline) (cFP), indole-3-carboxylic acid, phenylacetic acid (PAA) and indole-3-acetic acid. The production of the antimicrobial compound phenyllactic acid was exclusively detectable after VPA treatment. Furthermore three compounds, cPM, cFP, and PAA, were able to boost the antimicrobial activity of other antimicrobial compounds. cPM, for the first time isolated from fungi, and to a lesser extent PAA, are even able to decrease the minimal inhibitory concentration of ampicillin in MRSA strains. In conclusion we could show in this study that VPA treatment is a potent tool for induction of “cryptic” antimicrobial compound production in fungi, and that the induced compounds are not exclusively linked to the secondary metabolism. Furthermore this is the first discovery of the rare diketopiperazine cPM in fungi. Additionally we could demonstrate that cPM and PAA boost antibiotic activity against antibiotic resistant strains, suggesting a possible application in combinatorial antibiotic treatment against resistant pathogens.
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Affiliation(s)
- Christoph Zutz
- Institute for Milk Hygiene, University of Veterinary Medicine ViennaVienna, Austria; Research Platform Bioactive Microbial Metabolites, Bioresources and Technologies Campus in TullnTulln an der Donau, Austria
| | - Markus Bacher
- Division of Chemistry of Renewables, Department of Chemistry, University of Natural Resources and Life Sciences, Vienna Tulln an der Donau, Austria
| | - Alexandra Parich
- Center for Analytical Chemistry, Department of Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, Vienna Tulln an der Donau, Austria
| | - Bernhard Kluger
- Research Platform Bioactive Microbial Metabolites, Bioresources and Technologies Campus in TullnTulln an der Donau, Austria; Center for Analytical Chemistry, Department of Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, ViennaTulln an der Donau, Austria
| | - Agnieszka Gacek-Matthews
- Fungal Genetics and Genomics Unit, Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna Tulln an der Donau, Austria
| | - Rainer Schuhmacher
- Center for Analytical Chemistry, Department of Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, Vienna Tulln an der Donau, Austria
| | - Martin Wagner
- Institute for Milk Hygiene, University of Veterinary Medicine Vienna Vienna, Austria
| | - Kathrin Rychli
- Institute for Milk Hygiene, University of Veterinary Medicine Vienna Vienna, Austria
| | - Joseph Strauss
- Research Platform Bioactive Microbial Metabolites, Bioresources and Technologies Campus in TullnTulln an der Donau, Austria; Fungal Genetics and Genomics Unit, Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, ViennaTulln an der Donau, Austria; Health and Environment Department, Bioresources, Austrian Institute of Technology GmbH, University and Research Campus TullnTulln an der Donau, Austria
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1369
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Kumar A, Drozd M, Pina-Mimbela R, Xu X, Helmy YA, Antwi J, Fuchs JR, Nislow C, Templeton J, Blackall PJ, Rajashekara G. Novel Anti-Campylobacter Compounds Identified Using High Throughput Screening of a Pre-selected Enriched Small Molecules Library. Front Microbiol 2016; 7:405. [PMID: 27092106 PMCID: PMC4821856 DOI: 10.3389/fmicb.2016.00405] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Accepted: 03/14/2016] [Indexed: 12/12/2022] Open
Abstract
Campylobacter is a leading cause of foodborne bacterial gastroenteritis worldwide and infections can be fatal. The emergence of antibiotic-resistant Campylobacter spp. necessitates the development of new antimicrobials. We identified novel anti-Campylobacter small molecule inhibitors using a high throughput growth inhibition assay. To expedite screening, we made use of a "bioactive" library of 4182 compounds that we have previously shown to be active against diverse microbes. Screening for growth inhibition of Campylobacter jejuni, identified 781 compounds that were either bactericidal or bacteriostatic at a concentration of 200 μM. Seventy nine of the bactericidal compounds were prioritized for secondary screening based on their physico-chemical properties. Based on the minimum inhibitory concentration against a diverse range of C. jejuni and a lack of effect on gut microbes, we selected 12 compounds. No resistance was observed to any of these 12 lead compounds when C. jejuni was cultured with lethal or sub-lethal concentrations suggesting that C. jejuni is less likely to develop resistance to these compounds. Top 12 compounds also possessed low cytotoxicity to human intestinal epithelial cells (Caco-2 cells) and no hemolytic activity against sheep red blood cells. Next, these 12 compounds were evaluated for ability to clear C. jejuni in vitro. A total of 10 compounds had an anti-C. jejuni effect in Caco-2 cells with some effective even at 25 μM concentrations. These novel 12 compounds belong to five established antimicrobial chemical classes; piperazines, aryl amines, piperidines, sulfonamide, and pyridazinone. Exploitation of analogs of these chemical classes may provide Campylobacter specific drugs that can be applied in both human and animal medicine.
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Affiliation(s)
- Anand Kumar
- Food Animal Health Research Program, Department of Veterinary Preventive Medicine, The Ohio State UniversityWooster, OH, USA; Poultry CRC, University of New EnglandArmidale, NSW, Australia
| | - Mary Drozd
- Food Animal Health Research Program, Department of Veterinary Preventive Medicine, The Ohio State UniversityWooster, OH, USA; Poultry CRC, University of New EnglandArmidale, NSW, Australia
| | - Ruby Pina-Mimbela
- Food Animal Health Research Program, Department of Veterinary Preventive Medicine, The Ohio State University Wooster, OH, USA
| | - Xiulan Xu
- Department of Plant Pathology, Ohio Agricultural Research and Development Center, The Ohio State University Wooster, OH, USA
| | - Yosra A Helmy
- Food Animal Health Research Program, Department of Veterinary Preventive Medicine, The Ohio State University Wooster, OH, USA
| | - Janet Antwi
- College of Pharmacy, The Ohio State University Columbus, OH, USA
| | - James R Fuchs
- College of Pharmacy, The Ohio State University Columbus, OH, USA
| | - Corey Nislow
- Pharmaceutical Sciences, The University of British Columbia Vancouver, BC, Canada
| | - Jillian Templeton
- Department of Agriculture and Fisheries, EcoSciences Precinct Dutton Park, QLD, Australia
| | - Patrick J Blackall
- Poultry CRC, University of New EnglandArmidale, NSW, Australia; Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, EcoSciences PrecinctDutton Park, QLD, Australia
| | - Gireesh Rajashekara
- Food Animal Health Research Program, Department of Veterinary Preventive Medicine, The Ohio State University Wooster, OH, USA
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1370
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Zhang M, Kong X, Zheng J, Wan JB, Wang Y, Hu Y, Shao R. Research and development of antibiotics: insights from patents and citation network. Expert Opin Ther Pat 2016; 26:617-27. [PMID: 26986226 DOI: 10.1517/13543776.2016.1167877] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
INTRODUCTION Bacterial resistance to antibiotics develops at an alarming rate and leads to the increasing morbidity and health-care costs in recent years. However, the global research and development (R&D) of antibiotics has fallen behind the emergence and spread of bacterial resistance and the world is heading towards a 'post-antibiotic era'. In this context, systematic understanding of the technology landscape and evolving process of antibiotic R&D may help to provide insights for discovering future antibiotics more rationally. AREAS COVERED Patents and patent citations are broadly believed to be powerful tools in representing the technology advances and capturing technology flows. In all, 707 U.S. patents related to antibiotic R&D are collected and analyzed. Furthermore, patent citations are visualized by a network-based approach, while the inter-relationship between patented technologies on antibiotics is further revealed. EXPERT OPINION The current dry pipeline of antibiotic development requires substantial awareness and political support. It is essential to build an attractive and supportive environment for investment. Thus, a new antibiotic business model is needed to chase the balance between the market-oriented investment and public health goals. Additionally, drug development targeting Gram-negative bacteria, especially resistant Gram-negative bacteria, demands attentions from stakeholders because of their unmet medical needs.
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Affiliation(s)
- Meng Zhang
- a School of International Pharmaceutical Business , China Pharmaceutical University , Nanjing , Jiangsu , China
| | - Xiangjun Kong
- b Institute of Chinese Medical Sciences, State Key Laboratory of Quality Research in Chinese Medicine , University of Macau , Macao , China
| | - Jun Zheng
- c Faculty of Health Sciences , University of Macau , Macao , China
| | - Jian-Bo Wan
- b Institute of Chinese Medical Sciences, State Key Laboratory of Quality Research in Chinese Medicine , University of Macau , Macao , China
| | - Yitao Wang
- b Institute of Chinese Medical Sciences, State Key Laboratory of Quality Research in Chinese Medicine , University of Macau , Macao , China
| | - Yuanjia Hu
- b Institute of Chinese Medical Sciences, State Key Laboratory of Quality Research in Chinese Medicine , University of Macau , Macao , China
| | - Rong Shao
- a School of International Pharmaceutical Business , China Pharmaceutical University , Nanjing , Jiangsu , China
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1371
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1372
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Ayrapetyan M, Oliver JD. The viable but non-culturable state and its relevance in food safety. Curr Opin Food Sci 2016. [DOI: 10.1016/j.cofs.2016.04.010] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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1373
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Abstract
Despite the importance of microbial natural products for human health, only a few bacterial genera have been mined for the new natural products needed to overcome the urgent threat of antibiotic resistance. This is surprising, given that genome sequencing projects have revealed that the capability to produce natural products is not a rare feature among bacteria. Even the bacteria occurring in the human microbiome produce potent antibiotics, and thus potentially are an untapped resource for novel compounds, potentially with new activities. This review highlights examples of bacteria that should be considered new sources of natural products, including anaerobes, pathogens, and symbionts of humans, insects, and nematodes. Exploitation of these producer strains, combined with advances in modern natural product research methodology, has the potential to open the way for a new golden age of microbial therapeutics.
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Affiliation(s)
- Victoria L Challinor
- Merck Stiftungsprofessur für Molekulare Biotechnologie, Fachbereich Biowissenschaften, Goethe Universität Frankfurt, Frankfurt am Main, Germany
| | - Helge B Bode
- Merck Stiftungsprofessur für Molekulare Biotechnologie, Fachbereich Biowissenschaften, Goethe Universität Frankfurt, Frankfurt am Main, Germany.,Buchmann Institute for Molecular Life Sciences (BMLS), Goethe Universität Frankfurt, Frankfurt am Main, Germany
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1374
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Lyddiard D, Jones GL, Greatrex BW. Keeping it simple: lessons from the golden era of antibiotic discovery. FEMS Microbiol Lett 2016; 363:fnw084. [PMID: 27036144 DOI: 10.1093/femsle/fnw084] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/29/2016] [Indexed: 11/14/2022] Open
Abstract
Bacteria are becoming increasingly resistant to currently used antibiotics. At the same time, little progress has been made in discovering new antibacterial drugs to combat resistant organisms. History teaches us that 'high tech' target-based complex methods are not synonymous with success and a return to simple, systematic screening of natural products against bacteria from traditional and novel resources holds our greatest hope of success.
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Affiliation(s)
- Dane Lyddiard
- School of Science and Technology, University of New England, Armidale NSW 2351, Australia
| | - Graham L Jones
- School of Science and Technology, University of New England, Armidale NSW 2351, Australia
| | - Ben W Greatrex
- School of Science and Technology, University of New England, Armidale NSW 2351, Australia
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1375
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The Role of Biotin in Bacterial Physiology and Virulence: a Novel Antibiotic Target for
Mycobacterium tuberculosis. Microbiol Spectr 2016; 4. [DOI: 10.1128/microbiolspec.vmbf-0008-2015] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
ABSTRACT
Biotin is an essential cofactor for enzymes present in key metabolic pathways such as fatty acid biosynthesis, replenishment of the tricarboxylic acid cycle, and amino acid metabolism. Biotin is synthesized
de novo
in microorganisms, plants, and fungi, but this metabolic activity is absent in mammals, making biotin biosynthesis an attractive target for antibiotic discovery. In particular, biotin biosynthesis plays important metabolic roles as the sole source of biotin in all stages of the
Mycobacterium tuberculosis
life cycle due to the lack of a transporter for scavenging exogenous biotin. Biotin is intimately associated with lipid synthesis where the products form key components of the mycobacterial cell membrane that are critical for bacterial survival and pathogenesis. In this review we discuss the central role of biotin in bacterial physiology and highlight studies that demonstrate the importance of its biosynthesis for virulence. The structural biology of the known biotin synthetic enzymes is described alongside studies using structure-guided design, phenotypic screening, and fragment-based approaches to drug discovery as routes to new antituberculosis agents.
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1376
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Yarlagadda V, Sarkar P, Samaddar S, Haldar J. A Vancomycin Derivative with a Pyrophosphate-Binding Group: A Strategy to Combat Vancomycin-Resistant Bacteria. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201601621] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Venkateswarlu Yarlagadda
- Chemical Biology and Medicinal Chemistry Laboratory; New Chemistry Unit; Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR); Jakkur, Bengaluru 560064 Karnataka India
| | - Paramita Sarkar
- Chemical Biology and Medicinal Chemistry Laboratory; New Chemistry Unit; Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR); Jakkur, Bengaluru 560064 Karnataka India
| | - Sandip Samaddar
- Chemical Biology and Medicinal Chemistry Laboratory; New Chemistry Unit; Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR); Jakkur, Bengaluru 560064 Karnataka India
| | - Jayanta Haldar
- Chemical Biology and Medicinal Chemistry Laboratory; New Chemistry Unit; Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR); Jakkur, Bengaluru 560064 Karnataka India
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1377
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Yarlagadda V, Sarkar P, Samaddar S, Haldar J. A Vancomycin Derivative with a Pyrophosphate-Binding Group: A Strategy to Combat Vancomycin-Resistant Bacteria. Angew Chem Int Ed Engl 2016; 55:7836-40. [DOI: 10.1002/anie.201601621] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 03/07/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Venkateswarlu Yarlagadda
- Chemical Biology and Medicinal Chemistry Laboratory; New Chemistry Unit; Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR); Jakkur, Bengaluru 560064 Karnataka India
| | - Paramita Sarkar
- Chemical Biology and Medicinal Chemistry Laboratory; New Chemistry Unit; Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR); Jakkur, Bengaluru 560064 Karnataka India
| | - Sandip Samaddar
- Chemical Biology and Medicinal Chemistry Laboratory; New Chemistry Unit; Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR); Jakkur, Bengaluru 560064 Karnataka India
| | - Jayanta Haldar
- Chemical Biology and Medicinal Chemistry Laboratory; New Chemistry Unit; Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR); Jakkur, Bengaluru 560064 Karnataka India
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1378
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Affiliation(s)
- Mathieu F. Chellat
- Institut für Chemie und Biotechnologie, FS Organische Chemie und Medizinalchemie; Zürcher Hochschule für Angewandte Wissenschaften (ZHAW); Einsiedlerstrasse 31 CH-8820 Wädenswil Schweiz
| | - Luka Raguž
- Institut für Chemie und Biotechnologie, FS Organische Chemie und Medizinalchemie; Zürcher Hochschule für Angewandte Wissenschaften (ZHAW); Einsiedlerstrasse 31 CH-8820 Wädenswil Schweiz
| | - Rainer Riedl
- Institut für Chemie und Biotechnologie, FS Organische Chemie und Medizinalchemie; Zürcher Hochschule für Angewandte Wissenschaften (ZHAW); Einsiedlerstrasse 31 CH-8820 Wädenswil Schweiz
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1379
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Hurley KA, Santos TMA, Nepomuceno GM, Huynh V, Shaw JT, Weibel DB. Targeting the Bacterial Division Protein FtsZ. J Med Chem 2016; 59:6975-98. [DOI: 10.1021/acs.jmedchem.5b01098] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Katherine A. Hurley
- Department of Pharmaceutical Sciences, University of Wisconsin—Madison, 777 Highland Avenue, Madison, Wisconsin 53705, United States
| | - Thiago M. A. Santos
- Department
of Biochemistry, University of Wisconsin—Madison, 440 Henry Mall, Madison, Wisconsin 53706, United States
| | - Gabriella M. Nepomuceno
- Department of Chemistry, University of California—Davis, One Shields Avenue, Davis, California 95616, United States
| | - Valerie Huynh
- Department of Chemistry, University of California—Davis, One Shields Avenue, Davis, California 95616, United States
| | - Jared T. Shaw
- Department of Chemistry, University of California—Davis, One Shields Avenue, Davis, California 95616, United States
| | - Douglas B. Weibel
- Department
of Biochemistry, University of Wisconsin—Madison, 440 Henry Mall, Madison, Wisconsin 53706, United States
- Department of Chemistry, University of Wisconsin—Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
- Department of Biomedical Engineering, University of Wisconsin—Madison, 1550 Engineering Drive, Madison, Wisconsin 53706, United States
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1380
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Tutelyan AV, Gaponov AM, Pisarev VM, El-Registan GI. [Microbial dormancy and prevention of healthcare-associated infections]. TERAPEVT ARKH 2016; 87:103-108. [PMID: 26821426 DOI: 10.17116/terarkh20158711103-109] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Healthcare-associated infections (HCAI) remain one of the most challenges of modern health care and assume increasing social and medical significance. The specific features of HCAI are frequent recurrences and inefficiency of antibiotic therapy, a reason for which is antibiotic resistance in microorganisms. The review discusses antibiotic resistance, a form of antibiotic tolerance (AT), and its role in the development of HCAI. It also describes essential differences between AT and antibiotic tolerance at the cellular and molecular genetic levels. Relationships between AT and dormancy of microorganisms, pathogens of HCAI, are discussed. The paper gives the data available in the literature on how AT occurs in HCAI pathogens and discusses the diagnosis of this condition. It also analyzes the literature data on pharmacological attempts to overcome AT and discusses novel approaches to antibiotic therapy for HCAI.
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Affiliation(s)
- A V Tutelyan
- Central Research Institute of Epidemiology, Russian Federal Service for Supervision of Consumer Rights Protection and Human Welfare, Moscow, Russia; Dmitry Rogachev Federal Research-and-Clinical Center for Pediatric Hematology, Oncology, and Immunology, Ministry of Health of Russia, Moscow, Russia; I.M. Sechenov First Moscow State Medical University, Ministry of Health of Russia, Moscow, Russia
| | - A M Gaponov
- Central Research Institute of Epidemiology, Russian Federal Service for Supervision of Consumer Rights Protection and Human Welfare, Moscow, Russia; Dmitry Rogachev Federal Research-and-Clinical Center for Pediatric Hematology, Oncology, and Immunology, Ministry of Health of Russia, Moscow, Russia; V.A.Negovsky Research Institute of General Reanimatology, Federal Agency of Research Organizations of Russia, Moscow, Russia
| | - V M Pisarev
- Central Research Institute of Epidemiology, Russian Federal Service for Supervision of Consumer Rights Protection and Human Welfare, Moscow, Russia; Dmitry Rogachev Federal Research-and-Clinical Center for Pediatric Hematology, Oncology, and Immunology, Ministry of Health of Russia, Moscow, Russia; V.A.Negovsky Research Institute of General Reanimatology, Federal Agency of Research Organizations of Russia, Moscow, Russia
| | - G I El-Registan
- S.N. Vinogradsky Institute of Microbiology, Russian Academy of Sciences, Moscow, Russia
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1381
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Antibacterial activity and mechanism of action of auranofin against multi-drug resistant bacterial pathogens. Sci Rep 2016; 6:22571. [PMID: 26936660 PMCID: PMC4776257 DOI: 10.1038/srep22571] [Citation(s) in RCA: 125] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 02/17/2016] [Indexed: 11/18/2022] Open
Abstract
Traditional methods employed to discover new antibiotics are both a time-consuming and financially-taxing venture. This has led researchers to mine existing libraries of clinical molecules in order to repurpose old drugs for new applications (as antimicrobials). Such an effort led to the discovery of auranofin, a drug initially approved as an anti-rheumatic agent, which also possesses potent antibacterial activity in a clinically achievable range. The present study demonstrates auranofin’s antibacterial activity is a complex process that involves inhibition of multiple biosynthetic pathways including cell wall, DNA, and bacterial protein synthesis. We also confirmed that the lack of activity of auranofin observed against Gram-negative bacteria is due to the permeability barrier conferred by the outer membrane. Auranofin’s ability to suppress bacterial protein synthesis leads to significant reduction in the production of key methicillin-resistant Staphylococcus aureus (MRSA) toxins. Additionally, auranofin is capable of eradicating intracellular MRSA present inside infected macrophage cells. Furthermore, auranofin is efficacious in a mouse model of MRSA systemic infection and significantly reduces the bacterial load in murine organs including the spleen and liver. Collectively, this study provides valuable evidence that auranofin has significant promise to be repurposed as a novel antibacterial for treatment of invasive bacterial infections.
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1382
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Nanotechnology Formulations for Antibacterial Free Fatty Acids and Monoglycerides. Molecules 2016; 21:305. [PMID: 26950108 PMCID: PMC6273827 DOI: 10.3390/molecules21030305] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 02/17/2016] [Accepted: 02/23/2016] [Indexed: 01/01/2023] Open
Abstract
Free fatty acids and monoglycerides have long been known to possess broad-spectrum antibacterial activity that is based on lytic behavior against bacterial cell membranes. Considering the growing challenges of drug-resistant bacteria and the need for new classes of antibiotics, the wide prevalence, affordable cost, and broad spectrum of fatty acids and monoglycerides make them attractive agents to develop for healthcare and biotechnology applications. The aim of this review is to provide a brief introduction to the history of antimicrobial lipids and their current status and challenges, and to present a detailed discussion of ongoing research efforts to develop nanotechnology formulations of fatty acids and monoglycerides that enable superior in vitro and in vivo performance. Examples of nano-emulsions, liposomes, solid lipid nanoparticles, and controlled release hydrogels are presented in order to highlight the potential that lies ahead for fatty acids and monoglycerides as next-generation antibacterial solutions. Possible application routes and future directions in research and development are also discussed.
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1383
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Reusable nanoengineered surfaces for bacterial recruitment and decontamination. Biointerphases 2016; 11:019003. [DOI: 10.1116/1.4939239] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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1384
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Misra RS. The Microbiome, Antibiotics, and Health of the Pediatric Population. EC MICROBIOLOGY 2016; 3:388-390. [PMID: 27390782 PMCID: PMC4933318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Affiliation(s)
- Ravi S Misra
- Department of Pediatrics, University of Rochester Medical Center, New York
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1385
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Isothiocyanates as effective agents against enterohemorrhagic Escherichia coli: insight to the mode of action. Sci Rep 2016; 6:22263. [PMID: 26922906 PMCID: PMC4770323 DOI: 10.1038/srep22263] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 02/10/2016] [Indexed: 12/12/2022] Open
Abstract
Production of Shiga toxins by enterohemorrhagic Escherichia coli (EHEC) which is responsible for the pathogenicity of these strains, is strictly correlated with induction of lambdoid bacteriophages present in the host's genome, replication of phage DNA and expression of stx genes. Antibiotic treatment of EHEC infection may lead to induction of prophage into a lytic development, thus increasing the risk of severe complications. This, together with the spread of multi-drug resistance, increases the need for novel antimicrobial agents. We report here that isothiocyanates (ITC), plant secondary metabolites, such as sulforaphane (SFN), allyl isothiocyanate (AITC), benzyl isothiocynanate (BITC), phenyl isothiocyanate (PITC) and isopropyl isothiocyanate (IPRITC), inhibit bacterial growth and lytic development of stx-harboring prophages. The mechanism underlying the antimicrobial effect of ITCs involves the induction of global bacterial stress regulatory system, the stringent response. Its alarmone, guanosine penta/tetraphosphate ((p)ppGpp) affects major cellular processes, including nucleic acids synthesis, which leads to the efficient inhibition of both, prophage induction and toxin synthesis, abolishing in this way EHEC virulence for human and simian cells. Thus, ITCs could be considered as potential therapeutic agents in EHEC infections.
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1386
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Wong EHH, Khin MM, Ravikumar V, Si Z, Rice SA, Chan-Park MB. Modulating Antimicrobial Activity and Mammalian Cell Biocompatibility with Glucosamine-Functionalized Star Polymers. Biomacromolecules 2016; 17:1170-8. [PMID: 26859230 DOI: 10.1021/acs.biomac.5b01766] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The development of novel reagents and antibiotics for combating multidrug resistance bacteria has received significant attention in recent years. In this study, new antimicrobial star polymers (14-26 nm in diameter) that consist of mixtures of polylysine and glycopolymer arms were developed and were shown to possess antimicrobial efficacy toward Gram positive bacteria including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) (with MIC values as low as 16 μg mL(-1)) while being non-hemolytic (HC50 > 10,000 μg mL(-1)) and exhibit excellent mammalian cell biocompatibility. Structure function analysis indicated that the antimicrobial activity and mammalian cell biocompatibility of the star nanoparticles could be optimized by modifying the molar ratio of polylysine to glycopolymers arms. The technology described herein thus represents an innovative approach that could be used to fight deadly infectious diseases.
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Affiliation(s)
- Edgar H H Wong
- School of Chemical and Biomedical Engineering, and ‡Centre for Antimicrobial Bioengineering, Nanyang Technological University , Singapore 637459.,The Singapore Centre for Environmental Life Sciences Engineering, and ∥School of Biological Sciences, Nanyang Technological University , Singapore 637551
| | - Mya Mya Khin
- School of Chemical and Biomedical Engineering, and ‡Centre for Antimicrobial Bioengineering, Nanyang Technological University , Singapore 637459.,The Singapore Centre for Environmental Life Sciences Engineering, and ∥School of Biological Sciences, Nanyang Technological University , Singapore 637551
| | - Vikashini Ravikumar
- School of Chemical and Biomedical Engineering, and ‡Centre for Antimicrobial Bioengineering, Nanyang Technological University , Singapore 637459.,The Singapore Centre for Environmental Life Sciences Engineering, and ∥School of Biological Sciences, Nanyang Technological University , Singapore 637551
| | - Zhangyong Si
- School of Chemical and Biomedical Engineering, and ‡Centre for Antimicrobial Bioengineering, Nanyang Technological University , Singapore 637459.,The Singapore Centre for Environmental Life Sciences Engineering, and ∥School of Biological Sciences, Nanyang Technological University , Singapore 637551
| | - Scott A Rice
- School of Chemical and Biomedical Engineering, and ‡Centre for Antimicrobial Bioengineering, Nanyang Technological University , Singapore 637459.,The Singapore Centre for Environmental Life Sciences Engineering, and ∥School of Biological Sciences, Nanyang Technological University , Singapore 637551
| | - Mary B Chan-Park
- School of Chemical and Biomedical Engineering, and ‡Centre for Antimicrobial Bioengineering, Nanyang Technological University , Singapore 637459.,The Singapore Centre for Environmental Life Sciences Engineering, and ∥School of Biological Sciences, Nanyang Technological University , Singapore 637551
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1387
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Vijayasarathy S, Prasad P, Fremlin LJ, Ratnayake R, Salim AA, Khalil Z, Capon RJ. C3 and 2D C3 Marfey's Methods for Amino Acid Analysis in Natural Products. JOURNAL OF NATURAL PRODUCTS 2016; 79:421-7. [PMID: 26863178 DOI: 10.1021/acs.jnatprod.5b01125] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We validate the improved resolution and sensitivity of the C3 Marfey's method, including an ability to resolve all Ile isomers, against an array of amino acids commonly encountered in natural products and by comparison to an existing Marfey's method. We also describe an innovative 2D C3 Marfey's method as an analytical approach for determining the regiochemistry of enantiomeric amino acid residues in natural products. The C3 and 2D C3 Marfey's methods represent valuable tools for probing and defining the stereocomplexity of hydrolytically accessible amino acid residues in natural products.
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Affiliation(s)
- Soumini Vijayasarathy
- Institute for Molecular Bioscience, The University of Queensland , St. Lucia, Queensland 4072, Australia
| | - Pritesh Prasad
- Institute for Molecular Bioscience, The University of Queensland , St. Lucia, Queensland 4072, Australia
| | - Leith J Fremlin
- Institute for Molecular Bioscience, The University of Queensland , St. Lucia, Queensland 4072, Australia
| | - Ranjala Ratnayake
- Institute for Molecular Bioscience, The University of Queensland , St. Lucia, Queensland 4072, Australia
| | - Angela A Salim
- Institute for Molecular Bioscience, The University of Queensland , St. Lucia, Queensland 4072, Australia
| | - Zeinab Khalil
- Institute for Molecular Bioscience, The University of Queensland , St. Lucia, Queensland 4072, Australia
| | - Robert J Capon
- Institute for Molecular Bioscience, The University of Queensland , St. Lucia, Queensland 4072, Australia
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1388
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Gehring J, Trepka B, Klinkenberg N, Bronner H, Schleheck D, Polarz S. Sunlight-Triggered Nanoparticle Synergy: Teamwork of Reactive Oxygen Species and Nitric Oxide Released from Mesoporous Organosilica with Advanced Antibacterial Activity. J Am Chem Soc 2016; 138:3076-84. [DOI: 10.1021/jacs.5b12073] [Citation(s) in RCA: 121] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Julia Gehring
- Department of Chemistry and ‡Department of
Biology, University of Konstanz, Konstanz D-78457, Germany
| | - Bastian Trepka
- Department of Chemistry and ‡Department of
Biology, University of Konstanz, Konstanz D-78457, Germany
| | - Nele Klinkenberg
- Department of Chemistry and ‡Department of
Biology, University of Konstanz, Konstanz D-78457, Germany
| | - Hannah Bronner
- Department of Chemistry and ‡Department of
Biology, University of Konstanz, Konstanz D-78457, Germany
| | - David Schleheck
- Department of Chemistry and ‡Department of
Biology, University of Konstanz, Konstanz D-78457, Germany
| | - Sebastian Polarz
- Department of Chemistry and ‡Department of
Biology, University of Konstanz, Konstanz D-78457, Germany
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1389
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Screening of antitubercular compound library identifies novel shikimate kinase inhibitors of Mycobacterium tuberculosis. Appl Microbiol Biotechnol 2016; 100:5415-26. [DOI: 10.1007/s00253-015-7268-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2015] [Revised: 11/26/2015] [Accepted: 12/22/2015] [Indexed: 10/22/2022]
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1390
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Glycosyltransferases and Transpeptidases/Penicillin-Binding Proteins: Valuable Targets for New Antibacterials. Antibiotics (Basel) 2016; 5:antibiotics5010012. [PMID: 27025527 PMCID: PMC4810414 DOI: 10.3390/antibiotics5010012] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 01/27/2016] [Accepted: 02/03/2016] [Indexed: 12/29/2022] Open
Abstract
Peptidoglycan (PG) is an essential macromolecular sacculus surrounding most bacteria. It is assembled by the glycosyltransferase (GT) and transpeptidase (TP) activities of multimodular penicillin-binding proteins (PBPs) within multiprotein complex machineries. Both activities are essential for the synthesis of a functional stress-bearing PG shell. Although good progress has been made in terms of the functional and structural understanding of GT, finding a clinically useful antibiotic against them has been challenging until now. In contrast, the TP/PBP module has been successfully targeted by β-lactam derivatives, but the extensive use of these antibiotics has selected resistant bacterial strains that employ a wide variety of mechanisms to escape the lethal action of these antibiotics. In addition to traditional β-lactams, other classes of molecules (non-β-lactams) that inhibit PBPs are now emerging, opening new perspectives for tackling the resistance problem while taking advantage of these valuable targets, for which a wealth of structural and functional knowledge has been accumulated. The overall evidence shows that PBPs are part of multiprotein machineries whose activities are modulated by cofactors. Perturbation of these systems could lead to lethal effects. Developing screening strategies to take advantage of these mechanisms could lead to new inhibitors of PG assembly. In this paper, we present a general background on the GTs and TPs/PBPs, a survey of recent issues of bacterial resistance and a review of recent works describing new inhibitors of these enzymes.
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1391
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Yarlagadda V, Manjunath GB, Sarkar P, Akkapeddi P, Paramanandham K, Shome BR, Ravikumar R, Haldar J. Glycopeptide Antibiotic To Overcome the Intrinsic Resistance of Gram-Negative Bacteria. ACS Infect Dis 2016; 2:132-9. [PMID: 27624964 DOI: 10.1021/acsinfecdis.5b00114] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The emergence of drug resistance along with a declining pipeline of clinically useful antibiotics has made it vital to develop more effective antimicrobial therapeutics, particularly against difficult-to-treat Gram-negative pathogens (GNPs). Many antibacterial agents, including glycopeptide antibiotics such as vancomycin, are inherently inactive toward GNPs because of their inability to cross the outer membrane of these pathogens. Here, we demonstrate, for the first time, lipophilic cationic (permanent positive charge) vancomycin analogues were able to permeabilize the outer membrane of GNPs and overcome the inherent resistance of GNPs toward glycopeptides. Unlike vancomycin, these analogues were shown to have a high activity against a variety of multidrug-resistant clinical isolates such as Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii. In the murine model of carbapenem-resistant A. baumannii infection, the optimized compound showed potent activity with no observed toxicity. The notable activity of these compounds is attributed to the incorporation of new membrane disruption mechanisms (cytoplasmic membrane depolarization along with outer and inner (cytoplasmic) membrane permeabilization) into vancomycin. Therefore, our results indicate the potential of the present vancomycin analogues to be used against drug-resistant GNPs, thus strengthening the antibiotic arsenal for combating Gram-negative bacterial infections.
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Affiliation(s)
- Venkateswarlu Yarlagadda
- Chemical Biology and Medicinal Chemistry
Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru 560064, Karnataka, India
| | - Goutham B. Manjunath
- Chemical Biology and Medicinal Chemistry
Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru 560064, Karnataka, India
| | - Paramita Sarkar
- Chemical Biology and Medicinal Chemistry
Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru 560064, Karnataka, India
| | - Padma Akkapeddi
- Chemical Biology and Medicinal Chemistry
Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru 560064, Karnataka, India
| | - Krishnamoorthy Paramanandham
- National Institute of Veterinary Epidemiology and Disease Informatics (NIVEDI) Yelahanka, Bengaluru 560064, Karnataka, India
| | - Bibek R. Shome
- National Institute of Veterinary Epidemiology and Disease Informatics (NIVEDI) Yelahanka, Bengaluru 560064, Karnataka, India
| | - Raju Ravikumar
- Department of Neuromicrobiology, National Institute of Mental Health and Neuro Sciences, Hosur Road, Bengaluru 560029, Karnataka, India
| | - Jayanta Haldar
- Chemical Biology and Medicinal Chemistry
Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru 560064, Karnataka, India
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1392
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Shin JM, Gwak JW, Kamarajan P, Fenno JC, Rickard AH, Kapila YL. Biomedical applications of nisin. J Appl Microbiol 2016; 120:1449-65. [PMID: 26678028 DOI: 10.1111/jam.13033] [Citation(s) in RCA: 309] [Impact Index Per Article: 38.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 11/20/2015] [Accepted: 12/07/2015] [Indexed: 12/16/2022]
Abstract
Nisin is a bacteriocin produced by a group of Gram-positive bacteria that belongs to Lactococcus and Streptococcus species. Nisin is classified as a Type A (I) lantibiotic that is synthesized from mRNA and the translated peptide contains several unusual amino acids due to post-translational modifications. Over the past few decades, nisin has been used widely as a food biopreservative. Since then, many natural and genetically modified variants of nisin have been identified and studied for their unique antimicrobial properties. Nisin is FDA approved and generally regarded as a safe peptide with recognized potential for clinical use. Over the past two decades the application of nisin has been extended to biomedical fields. Studies have reported that nisin can prevent the growth of drug-resistant bacterial strains, such as methicillin-resistant Staphylococcus aureus, Streptococcus pneumoniae, Enterococci and Clostridium difficile. Nisin has now been shown to have antimicrobial activity against both Gram-positive and Gram-negative disease-associated pathogens. Nisin has been reported to have anti-biofilm properties and can work synergistically in combination with conventional therapeutic drugs. In addition, like host-defence peptides, nisin may activate the adaptive immune response and have an immunomodulatory role. Increasing evidence indicates that nisin can influence the growth of tumours and exhibit selective cytotoxicity towards cancer cells. Collectively, the application of nisin has advanced beyond its role as a food biopreservative. Thus, this review will describe and compare studies on nisin and provide insight into its future biomedical applications.
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Affiliation(s)
- J M Shin
- Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, USA.,Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI, USA
| | - J W Gwak
- Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, USA
| | - P Kamarajan
- Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, USA
| | - J C Fenno
- Department of Biologic and Materials Sciences, University of Michigan School of Dentistry, Ann Arbor, MI, USA
| | - A H Rickard
- Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI, USA
| | - Y L Kapila
- Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, USA
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1393
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Cochrane SA, Lohans CT, van Belkum MJ, Bels MA, Vederas JC. Studies on tridecaptin B(1), a lipopeptide with activity against multidrug resistant Gram-negative bacteria. Org Biomol Chem 2016; 13:6073-81. [PMID: 25959079 DOI: 10.1039/c5ob00780a] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Previously other groups had reported that Paenibacillus polymyxa NRRL B-30507 produces SRCAM 37, a type IIA bacteriocin with antimicrobial activity against Campylobacter jejuni. Genome sequencing and isolation of antimicrobial compounds from this P. polymyxa strain show that the antimicrobial activity is due to polymyxins and tridecaptin B1. The complete structural assignment, synthesis, and antimicrobial profile of tridecaptin B1 is reported, as well as the putative gene cluster responsible for its biosynthesis. This peptide displays strong activity against multidrug resistant Gram-negative bacteria, a finding that is timely to the current problem of antibiotic resistance.
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Affiliation(s)
- Stephen A Cochrane
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta T6E 2M9, Canada.
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1394
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Cibrián-Jaramillo A, Barona-Gómez F. Increasing Metagenomic Resolution of Microbiome Interactions Through Functional Phylogenomics and Bacterial Sub-Communities. Front Genet 2016; 7:4. [PMID: 26904093 PMCID: PMC4748306 DOI: 10.3389/fgene.2016.00004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 01/17/2016] [Indexed: 11/13/2022] Open
Abstract
The genomic composition of the microbiome and its relationship with the environment is an exciting open question in biology. Metagenomics is a useful tool in the discovery of previously unknown taxa, but its use to understand the functional and ecological capacities of the microbiome is limited until taxonomy and function are understood in the context of the community. We suggest that this can be achieved using a combined functional phylogenomics and co-culture-based experimental strategy that can increase our capacity to measure sub-community interactions. Functional phylogenomics can identify and partition the genome such that hidden gene functions and gene clusters with unique evolutionary signals are revealed. We can test these phylogenomic predictions using an experimental model based on sub-community populations that represent a subset of the diversity directly obtained from environmental samples. These populations increase the detection of mechanisms that drive functional forces in the assembly of the microbiome, in particular the role of metabolites from key taxa in community interactions. Our combined approach leverages the potential of metagenomics to address biological questions from ecological systems.
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Affiliation(s)
- Angélica Cibrián-Jaramillo
- Laboratorio Nacional de Genómica para la Biodiversidad (Langebio), Unidad de Genómica Avanzada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (Cinvestav) Irapuato, Mexico
| | - Francisco Barona-Gómez
- Laboratorio Nacional de Genómica para la Biodiversidad (Langebio), Unidad de Genómica Avanzada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (Cinvestav) Irapuato, Mexico
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1395
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Abstract
Reconstruction of phylogenetic trees based on 16S rRNA gene sequencing reveals abundant microbial diversity that has not been cultured in the laboratory. Many attribute this so-called 'great plate count anomaly' to traditional microbial cultivation techniques, which largely facilitate the growth of a single species. Yet, it is widely recognized that bacteria in nature exist in complex communities. One technique to increase the pool of cultivated bacterial species is to co-culture multiple species in a simulated natural environment. Here, we present nanoporous microscale microbial incubators (NMMI) that enable high-throughput screening and real-time observation of multi-species co-culture. The key innovation in NMMI is that they facilitate inter-species communication while maintaining physical isolation between species, which is ideal for genomic analysis. Co-culture of a quorum sensing pair demonstrates that the NMMI can be used to culture multiple species in chemical communication while monitoring the growth dynamics of individual species.
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Affiliation(s)
- Zhifei Ge
- Department of Mechanical Engineering, Massachusetts Institute of Technology, USA.
| | - Peter R Girguis
- Department of Organismic and Evolutionary Biology, Harvard University, USA
| | - Cullen R Buie
- Department of Mechanical Engineering, Massachusetts Institute of Technology, USA.
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1396
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High-Throughput Single-Cell Cultivation on Microfluidic Streak Plates. Appl Environ Microbiol 2016; 82:2210-8. [PMID: 26850294 DOI: 10.1128/aem.03588-15] [Citation(s) in RCA: 110] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 01/19/2016] [Indexed: 12/16/2022] Open
Abstract
This paper describes the microfluidic streak plate (MSP), a facile method for high-throughput microbial cell separation and cultivation in nanoliter sessile droplets. The MSP method builds upon the conventional streak plate technique by using microfluidic devices to generate nanoliter droplets that can be streaked manually or robotically onto petri dishes prefilled with carrier oil for cultivation of single cells. In addition, chemical gradients could be encoded in the droplet array for comprehensive dose-response analysis. The MSP method was validated by using single-cell isolation of Escherichia coli and antimicrobial susceptibility testing of Pseudomonas aeruginosa PAO1. The robustness of the MSP work flow was demonstrated by cultivating a soil community that degrades polycyclic aromatic hydrocarbons. Cultivation in droplets enabled detection of the richest species diversity with better coverage of rare species. Moreover, isolation and cultivation of bacterial strains by MSP led to the discovery of several species with high degradation efficiency, including four Mycobacterium isolates and a previously unknown fluoranthene-degrading Blastococcus species.
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1397
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Gutsmann T. Interaction between antimicrobial peptides and mycobacteria. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:1034-43. [PMID: 26851776 DOI: 10.1016/j.bbamem.2016.01.031] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Revised: 01/29/2016] [Accepted: 01/31/2016] [Indexed: 01/21/2023]
Abstract
Mycobacteria can cause different severe health problems, including tuberculosis (TB). The treatment of TB with conventional antibiotics is successful, however, the number of multi-drug and extensively-drug resistant Mycobacterium tuberculosis strains increases. Moreover, many classical antimycobacterial antibiotics have severe side effects. Therefore, antimicrobial peptides (AMPs) seem to be good candidates for new therapeutic strategies. On the one hand AMPs can be used as a single drug or in combination with conventional antibiotics to directly kill mycobacteria, or on the other hand to act as immunstimulatory agents. This review summarizes the findings on the role of endogenous human AMPs being involved in TB, the antimycobacterial activity of various AMPs, and the molecular modes of action. Most active AMPs interact with the mycobacterial cell envelope and in particular with the mycomembrane and the plasma membrane. The mycomembrane is a very rigid membrane probably leading to a lower activity of the AMPs against mycobacteria as compared to other Gram-negative or Gram-positive bacteria. For some AMPs also other targets have been identified. Because of the complex environment of intracellular mycobacteria being trapped in the phagosome, within the macrophage, within the granuloma, within the lung, the external administration of AMPs in the latent phase of TB is a challenge. However, in the acute phase the AMPs can attack mycobacteria in a direct way. This article is part of a Special Issue entitled: Antimicrobial peptides edited by Karl Lohner and Kai Hilpert.
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Affiliation(s)
- Thomas Gutsmann
- Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Priority Area Infections, Division of Biophysics, Parkallee 10, 23845 Borstel, Germany.
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1398
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Randhawa HK, Gautam A, Sharma M, Bhatia R, Varshney GC, Raghava GPS, Nandanwar H. Cell-penetrating peptide and antibiotic combination therapy: a potential alternative to combat drug resistance in methicillin-resistant Staphylococcus aureus. Appl Microbiol Biotechnol 2016; 100:4073-83. [DOI: 10.1007/s00253-016-7329-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 01/06/2016] [Accepted: 01/17/2016] [Indexed: 10/22/2022]
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1399
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Assembly and clustering of natural antibiotics guides target identification. Nat Chem Biol 2016; 12:233-9. [PMID: 26829473 DOI: 10.1038/nchembio.2018] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 12/09/2015] [Indexed: 12/25/2022]
Abstract
Antibiotics are essential for numerous medical procedures, including the treatment of bacterial infections, but their widespread use has led to the accumulation of resistance, prompting calls for the discovery of antibacterial agents with new targets. A majority of clinically approved antibacterial scaffolds are derived from microbial natural products, but these valuable molecules are not well annotated or organized, limiting the efficacy of modern informatic analyses. Here, we provide a comprehensive resource defining the targets, chemical origins and families of the natural antibacterial collective through a retrobiosynthetic algorithm. From this we also detail the directed mining of biosynthetic scaffolds and resistance determinants to reveal structures with a high likelihood of having previously unknown modes of action. Implementing this pipeline led to investigations of the telomycin family of natural products from Streptomyces canus, revealing that these bactericidal molecules possess a new antibacterial mode of action dependent on the bacterial phospholipid cardiolipin.
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Reimer JM, Aloise MN, Harrison PM, Schmeing TM. Synthetic cycle of the initiation module of a formylating nonribosomal peptide synthetase. Nature 2016; 529:239-42. [PMID: 26762462 DOI: 10.1038/nature16503] [Citation(s) in RCA: 117] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2015] [Accepted: 12/02/2015] [Indexed: 12/22/2022]
Abstract
Nonribosomal peptide synthetases (NRPSs) are very large proteins that produce small peptide molecules with wide-ranging biological activities, including environmentally friendly chemicals and many widely used therapeutics. NRPSs are macromolecular machines, with modular assembly-line logic, a complex catalytic cycle, moving parts and many active sites. In addition to the core domains required to link the substrates, they often include specialized tailoring domains, which introduce chemical modifications and allow the product to access a large expanse of chemical space. It is still unknown how the NRPS tailoring domains are structurally accommodated into megaenzymes or how they have adapted to function in nonribosomal peptide synthesis. Here we present a series of crystal structures of the initiation module of an antibiotic-producing NRPS, linear gramicidin synthetase. This module includes the specialized tailoring formylation domain, and states are captured that represent every major step of the assembly-line synthesis in the initiation module. The transitions between conformations are large in scale, with both the peptidyl carrier protein domain and the adenylation subdomain undergoing huge movements to transport substrate between distal active sites. The structures highlight the great versatility of NRPSs, as small domains repurpose and recycle their limited interfaces to interact with their various binding partners. Understanding tailoring domains is important if NRPSs are to be utilized in the production of novel therapeutics.
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Affiliation(s)
- Janice M Reimer
- Department of Biochemistry, McGill University, 3649 Promenade Sir-William-Osler, Montréal, Québec H3G 0B1, Canada
| | - Martin N Aloise
- Department of Biochemistry, McGill University, 3649 Promenade Sir-William-Osler, Montréal, Québec H3G 0B1, Canada
| | - Paul M Harrison
- Department of Biology, McGill University, 1205 Dr Penfield Avenue, Montréal, Québec H3A 1B1, Canada
| | - T Martin Schmeing
- Department of Biochemistry, McGill University, 3649 Promenade Sir-William-Osler, Montréal, Québec H3G 0B1, Canada
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