151
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Kohanski MA, Tharakan A, London NR, Lane AP, Ramanathan M. Bactericidal antibiotics promote oxidative damage and programmed cell death in sinonasal epithelial cells. Int Forum Allergy Rhinol 2017; 7:359-364. [PMID: 28117948 DOI: 10.1002/alr.21914] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Revised: 12/05/2016] [Accepted: 12/14/2016] [Indexed: 11/06/2022]
Abstract
BACKGROUND Antibiotics are widely and heavily used in the treatment of chronic sinusitis. Bactericidal antibiotics can stimulate reactive oxygen species (ROS) formation, a proinflammatory response, and cell death in cultured human sinonasal epithelial cells (SNECs). Sulforaphane (SFN) is a potent stimulator of the antioxidant nuclear factor erythroid 2-related factor 2 (Nrf-2) system and a suppressor of inflammation. In this study we utilized SFN to further explore the relationship between levofloxacin treatment, ROS formation, and the cell death response. METHODS SNECs were collected from patients during endoscopic sinus surgery and grown in culture at the air-liquid interface. Differentiated SNECs were stimulated with levofloxacin with or without SFN pretreatment. ROS were quantified. Apoptosis markers of caspase-3 activity and DNA fragmentation were quantified. RESULTS Cultured SNECs treated with levofloxacin resulted in a significant increase in activity of the proapoptotic caspase-3 protease (5.9-fold, p = 0.01). The increase in activity was suppressed by pretreatment with SFN (1.9-fold). ROS levels increased with levofloxacin treatment (range, 1.2-fold to 1.8-fold), but were not significantly suppressed by pretreatment with SFN (range, 1.0-fold to 1.3-fold). CONCLUSION In this study, we demonstrate that treatment of cultured SNECs with levofloxacin leads to an increase in caspase-3 activity. SFN pretreatment suppresses the increased apoptotic response possibly through its antioxidant stimulating properties. Our results suggest that levofloxacin treatment stimulates a potent proapoptotic possibly through an ROS-dependent mechanism. Future studies will explore if this antibiotic-induced response is harmful to recovery of function in those with sinusitis.
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Affiliation(s)
- Michael A Kohanski
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Anuj Tharakan
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Nyall R London
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Andrew P Lane
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Murugappan Ramanathan
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD
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152
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Meylan S, Porter CBM, Yang JH, Belenky P, Gutierrez A, Lobritz MA, Park J, Kim SH, Moskowitz SM, Collins JJ. Carbon Sources Tune Antibiotic Susceptibility in Pseudomonas aeruginosa via Tricarboxylic Acid Cycle Control. Cell Chem Biol 2017; 24:195-206. [PMID: 28111098 DOI: 10.1016/j.chembiol.2016.12.015] [Citation(s) in RCA: 232] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 11/21/2016] [Accepted: 12/28/2016] [Indexed: 10/20/2022]
Abstract
Metabolically dormant bacteria present a critical challenge to effective antimicrobial therapy because these bacteria are genetically susceptible to antibiotic treatment but phenotypically tolerant. Such tolerance has been attributed to impaired drug uptake, which can be reversed by metabolic stimulation. Here, we evaluate the effects of central carbon metabolite stimulations on aminoglycoside sensitivity in the pathogen Pseudomonas aeruginosa. We identify fumarate as a tobramycin potentiator that activates cellular respiration and generates a proton motive force by stimulating the tricarboxylic acid (TCA) cycle. In contrast, we find that glyoxylate induces phenotypic tolerance by inhibiting cellular respiration with acetyl-coenzyme A diversion through the glyoxylate shunt, despite drug import. Collectively, this work demonstrates that TCA cycle activity is important for both aminoglycoside uptake and downstream lethality and identifies a potential strategy for potentiating aminoglycoside treatment of P. aeruginosa infections.
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Affiliation(s)
- Sylvain Meylan
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA; Department of Biological Engineering, Institute for Medical Engineering & Science, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Division of Infectious Diseases, Brigham and Women's Hospital, Boston, MA 02115, USA; Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Caroline B M Porter
- Department of Biological Engineering, Institute for Medical Engineering & Science, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Jason H Yang
- Department of Biological Engineering, Institute for Medical Engineering & Science, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Peter Belenky
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02912, USA
| | - Arnaud Gutierrez
- Department of Biological Engineering, Institute for Medical Engineering & Science, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Michael A Lobritz
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA; Department of Biological Engineering, Institute for Medical Engineering & Science, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Jihye Park
- Department of Pediatrics, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Sun H Kim
- Department of Pediatrics, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Samuel M Moskowitz
- Department of Pediatrics, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - James J Collins
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA; Department of Biological Engineering, Institute for Medical Engineering & Science, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Harvard-MIT Program, Health Sciences and Technology, Cambridge, MA 02139, USA.
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153
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Van Acker H, Coenye T. The Role of Reactive Oxygen Species in Antibiotic-Mediated Killing of Bacteria. Trends Microbiol 2017; 25:456-466. [PMID: 28089288 DOI: 10.1016/j.tim.2016.12.008] [Citation(s) in RCA: 326] [Impact Index Per Article: 46.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 12/09/2016] [Accepted: 12/15/2016] [Indexed: 11/26/2022]
Abstract
Recently, it was proposed that there is a common mechanism behind the activity of bactericidal antibiotics, involving the production of reactive oxygen species (ROS). However, the involvement of ROS in antibiotic-mediated killing has become the subject of much debate. In the present review, we provide an overview of the data supporting the ROS hypothesis; we also present data that explain the contradictory results often obtained when studying antibiotic-induced ROS production. For this latter aspect we will focus on the importance of taking the experimental setup into consideration and on the importance of some technical aspects of the assays typically used. Finally, we discuss the link between ROS production and toxin-antitoxin modules, and present an overview of implications for treatment.
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Affiliation(s)
- Heleen Van Acker
- Laboratory of Pharmaceutical Microbiology, Ghent University, Ghent, Belgium
| | - Tom Coenye
- Laboratory of Pharmaceutical Microbiology, Ghent University, Ghent, Belgium.
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154
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Brito L, Wilton J, Ferrándiz MJ, Gómez-Sanz A, de la Campa AG, Amblar M. Absence of tmRNA Has a Protective Effect against Fluoroquinolones in Streptococcus pneumoniae. Front Microbiol 2017; 7:2164. [PMID: 28119681 PMCID: PMC5222879 DOI: 10.3389/fmicb.2016.02164] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 12/23/2016] [Indexed: 11/13/2022] Open
Abstract
The transfer messenger RNA (tmRNA), encoded by the ssrA gene, is a small non-coding RNA involved in trans-translation that contributes to the recycling of ribosomes stalled on aberrant mRNAs. In most bacteria, its inactivation has been related to a decreased ability to respond to and recover from a variety of stress conditions. In this report, we investigated the role of tmRNA in stress adaptation in the human pathogen Streptococcus pneumoniae. We constructed a tmRNA deletion mutant and analyzed its response to several lethal stresses. The ΔssrA strain grew slower than the wild type, indicating that, although not essential, tmRNA is important for normal pneumococcal growth. Moreover, deletion of tmRNA increased susceptibility to UV irradiation, to exogenous hydrogen peroxide and to antibiotics that inhibit protein synthesis and transcription. However, the ΔssrA strain was more resistant to fluoroquinolones, showing twofold higher MIC values and up to 1000-fold higher survival rates than the wild type. Deletion of SmpB, the other partner in trans-translation, also reduced survival to levofloxacin in a similar extent. Accumulation of intracellular reactive oxygen species associated to moxifloxacin and levofloxacin treatment was also highly reduced (∼100-fold). Nevertheless, the ΔssrA strain showed higher intracellular accumulation of ethidium bromide and levofloxacin than the wild type, suggesting that tmRNA deficiency protects pneumococcal cells from fluoroquinolone-mediated killing. In fact, analysis of chromosome integrity revealed that deletion of tmRNA prevented the fragmentation of the chromosome associated to levofloxacin treatment. Moreover, such protective effect appears to relay mainly on inhibition of protein synthesis, since a similar effect was observed with antibiotics that inhibit that process. The emergence and spread of drug-resistant pneumococci is a matter of concern and these results contribute to a better comprehension of the mechanisms underlying fluoroquinolones action.
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Affiliation(s)
- Liliana Brito
- Unidad de Patología Molecular del Neumococo, Centro Nacional de Microbiología, Instituto de Salud Carlos III Madrid, Spain
| | - Joana Wilton
- Unidad de Patología Molecular del Neumococo, Centro Nacional de Microbiología, Instituto de Salud Carlos III Madrid, Spain
| | - María J Ferrándiz
- Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos III Madrid, Spain
| | - Alicia Gómez-Sanz
- Unidad de Patología Molecular del Neumococo, Centro Nacional de Microbiología, Instituto de Salud Carlos III Madrid, Spain
| | - Adela G de la Campa
- Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos IIIMadrid, Spain; Presidencia, Consejo Superior de Investigaciones CientíficasMadrid, Spain
| | - Mónica Amblar
- Unidad de Patología Molecular del Neumococo, Centro Nacional de Microbiología, Instituto de Salud Carlos III Madrid, Spain
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155
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Vitorino GP, Becerra MC, Barrera GD, Caira MR, Mazzieri MR. Cooperative Behavior of Fluoroquinolone Combinations against Escherichia coli and Staphylococcus aureus. Biol Pharm Bull 2017; 40:758-764. [DOI: 10.1248/bpb.b16-00616] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Graciela Pinto Vitorino
- Departamento de Farmacia, Universidad Nacional de la Patagonia San Juan Bosco, Ciudad Universitaria
| | - María Cecilia Becerra
- Departamento de Farmacia, IMBIV-CONICET. Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria
| | - Gustavo Daniel Barrera
- Departamento de Química, Facultad de Ciencias Naturales, Universidad Nacional de la Patagonia San Juan Bosco, Ciudad Universitaria
| | | | - María Rosa Mazzieri
- Departamento de Farmacia, IMBIV-CONICET. Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria
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156
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Al-Emran HM, Heisig A, Dekker D, Adu-Sarkodie Y, Cruz Espinoza LM, Panzner U, von Kalckreuth V, Marks F, Park SE, Sarpong N, May J, Heisig P. Detection of a Novel gyrB Mutation Associated With Fluoroquinolone-Nonsusceptible Salmonella enterica serovar Typhimurium Isolated From a Bloodstream Infection in Ghana. Clin Infect Dis 2016; 62 Suppl 1:S47-9. [PMID: 26933021 DOI: 10.1093/cid/civ790] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A multidrug-resistant Salmonella enterica serovar Typhimurium with reduced susceptibility to ciprofloxacin was isolated from the blood of a hospitalized child in Ghana. DNA sequencing identified a novel gyrB mutation at codon 466 (Glu466Asp). An increase in fluoroquinolone susceptibility after the introduction of a wild-type gyrB(+) allele demonstrated that the gyrB466 mutation had a direct effect on fluoroquinolone susceptibility.
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Affiliation(s)
- Hassan M Al-Emran
- Bernhard-Nocht Institute for Tropical Medicine German Center for Infection Research, partner site Hamburg-Borstel-Lübeck
| | - Anke Heisig
- Institute of Biochemistry and Molecular Biology, University of Hamburg, Germany
| | - Denise Dekker
- Bernhard-Nocht Institute for Tropical Medicine German Center for Infection Research, partner site Hamburg-Borstel-Lübeck
| | - Yaw Adu-Sarkodie
- Kumasi Centre for Collaborative Research in Tropical Medicine, Ghana
| | | | - Ursula Panzner
- International Vaccine Institute, Seoul, Republic of Korea
| | | | - Florian Marks
- International Vaccine Institute, Seoul, Republic of Korea
| | - Se Eun Park
- International Vaccine Institute, Seoul, Republic of Korea
| | - Nimako Sarpong
- Kumasi Centre for Collaborative Research in Tropical Medicine, Ghana
| | - Jürgen May
- Bernhard-Nocht Institute for Tropical Medicine German Center for Infection Research, partner site Hamburg-Borstel-Lübeck
| | - Peter Heisig
- Institute of Biochemistry and Molecular Biology, University of Hamburg, Germany
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157
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Trimble MJ, Mlynárčik P, Kolář M, Hancock REW. Polymyxin: Alternative Mechanisms of Action and Resistance. Cold Spring Harb Perspect Med 2016; 6:cshperspect.a025288. [PMID: 27503996 DOI: 10.1101/cshperspect.a025288] [Citation(s) in RCA: 243] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Antibiotic resistance among pathogenic bacteria is an ever-increasing issue worldwide. Unfortunately, very little has been achieved in the pharmaceutical industry to combat this problem. This has led researchers and the medical field to revisit past drugs that were deemed too toxic for clinical use. In particular, the cyclic cationic peptides polymyxin B and colistin, which are specific for Gram-negative bacteria, have been used as "last resort" antimicrobials. Before the 1980s, these drugs were known for their renal and neural toxicities; however, new clinical practices and possibly improved manufacturing have made them safer to use. Previously suggested to primarily attack the membranes of Gram-negative bacteria and to not easily select for resistant mutants, recent research exploring resistance and mechanisms of action has provided new perspectives. This review focuses primarily on the proposed alternative mechanisms of action, known resistance mechanisms, and how these support the alternative mechanisms of action.
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Affiliation(s)
- Michael J Trimble
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Patrik Mlynárčik
- Department of Microbiology, Faculty of Medicine and Dentistry, Palacký University, 771 47 Olomouc, Czech Republic
| | - Milan Kolář
- Department of Microbiology, Faculty of Medicine and Dentistry, Palacký University, 771 47 Olomouc, Czech Republic
| | - Robert E W Hancock
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
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158
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Braff D, Shis D, Collins JJ. Synthetic biology platform technologies for antimicrobial applications. Adv Drug Deliv Rev 2016; 105:35-43. [PMID: 27089812 DOI: 10.1016/j.addr.2016.04.006] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 03/08/2016] [Accepted: 04/06/2016] [Indexed: 12/11/2022]
Abstract
The growing prevalence of antibiotic resistance calls for new approaches in the development of antimicrobial therapeutics. Likewise, improved diagnostic measures are essential in guiding the application of targeted therapies and preventing the evolution of therapeutic resistance. Discovery platforms are also needed to form new treatment strategies and identify novel antimicrobial agents. By applying engineering principles to molecular biology, synthetic biologists have developed platforms that improve upon, supplement, and will perhaps supplant traditional broad-spectrum antibiotics. Efforts in engineering bacteriophages and synthetic probiotics demonstrate targeted antimicrobial approaches that can be fine-tuned using synthetic biology-derived principles. Further, the development of paper-based, cell-free expression systems holds promise in promoting the clinical translation of molecular biology tools for diagnostic purposes. In this review, we highlight emerging synthetic biology platform technologies that are geared toward the generation of new antimicrobial therapies, diagnostics, and discovery channels.
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Affiliation(s)
- Dana Braff
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
| | - David Shis
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - James J Collins
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA; Harvard-MIT Program in Health Sciences and Technology, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
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159
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Kirbaeva NV, Sharanova NE, Zhminchenko VM, Toropygin IY, Koplik EV, Pertsov SS, Vasil'ev AV. Effect of Coenzyme Q10 on Proteomic Profile of Rat Brain Amygdala during Acute Metabolic Stress. Bull Exp Biol Med 2016; 161:460-4. [PMID: 27590759 DOI: 10.1007/s10517-016-3438-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2015] [Indexed: 11/29/2022]
Abstract
Differences in the proteomic profiles of the brain amygdala in rats with different prognostic resistance to stress were found on the model of metabolic stress. Differential expression of tropomodulin-2, GTP-binding protein SAR1, peroxiredoxin-2, calcineurin B homologous protein 1, Ras-related protein Rab-14, glutathione S-transferase omega-1, Tcrb protein, and NADH dehydrogenase [ubiquinone] iron-sulfur protein 8 (mitochondrial) was shown to depend on the behavioral pattern of animals and stage of the study. Specific features were observed in the involvement of the amygdala in the stress response of specimens with various behavioral characteristics.
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Affiliation(s)
- N V Kirbaeva
- Research Institute of Nutrition, Russian Academy of Medical Sciences, Moscow, Russia.
| | - N E Sharanova
- Research Institute of Nutrition, Russian Academy of Medical Sciences, Moscow, Russia
| | - V M Zhminchenko
- Research Institute of Nutrition, Russian Academy of Medical Sciences, Moscow, Russia
| | - I Yu Toropygin
- Center of Common Use "Human Proteome", V. I. Orekhovich Research Institute of Biomedical Chemistry, Moscow, Russia
| | - E V Koplik
- P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia
| | - S S Pertsov
- P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia
| | - A V Vasil'ev
- Research Institute of Nutrition, Russian Academy of Medical Sciences, Moscow, Russia
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160
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Esterberg R, Linbo T, Pickett SB, Wu P, Ou HC, Rubel EW, Raible DW. Mitochondrial calcium uptake underlies ROS generation during aminoglycoside-induced hair cell death. J Clin Invest 2016; 126:3556-66. [PMID: 27500493 DOI: 10.1172/jci84939] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 06/09/2016] [Indexed: 12/11/2022] Open
Abstract
Exposure to aminoglycoside antibiotics can lead to the generation of toxic levels of reactive oxygen species (ROS) within mechanosensory hair cells of the inner ear that have been implicated in hearing and balance disorders. Better understanding of the origin of aminoglycoside-induced ROS could focus the development of therapies aimed at preventing this event. In this work, we used the zebrafish lateral line system to monitor the dynamic behavior of mitochondrial and cytoplasmic oxidation occurring within the same dying hair cell following exposure to aminoglycosides. The increased oxidation observed in both mitochondria and cytoplasm of dying hair cells was highly correlated with mitochondrial calcium uptake. Application of the mitochondrial uniporter inhibitor Ru360 reduced mitochondrial and cytoplasmic oxidation, suggesting that mitochondrial calcium drives ROS generation during aminoglycoside-induced hair cell death. Furthermore, targeting mitochondria with free radical scavengers conferred superior protection against aminoglycoside exposure compared with identical, untargeted scavengers. Our findings suggest that targeted therapies aimed at preventing mitochondrial oxidation have therapeutic potential to ameliorate the toxic effects of aminoglycoside exposure.
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161
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Smirnova GV, Tyulenev AV, Muzyka NG, Peters MA, Oktyabrsky ON. Ciprofloxacin provokes SOS-dependent changes in respiration and membrane potential and causes alterations in the redox status of Escherichia coli. Res Microbiol 2016; 168:64-73. [PMID: 27498196 DOI: 10.1016/j.resmic.2016.07.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 07/25/2016] [Accepted: 07/27/2016] [Indexed: 10/21/2022]
Abstract
An in-depth understanding of the physiological response of bacteria to antibiotic-induced stress is needed for development of new approaches to combatting microbial infections. Fluoroquinolone ciprofloxacin causes phase alterations in Escherichia coli respiration and membrane potential that strongly depend on its concentration. Concentrations lower than the optimal bactericidal concentration (OBC) do not inhibit respiration during the first phase. A dose higher than the OBC provokes immediate SOS-independent inhibition of respiration and growth that can contribute to a decreased SOS response and lowered susceptibility to high concentrations of ciprofloxacin. Cells retain their metabolic activity, membrane potential and accelerated K+ uptake and produce low levels of superoxide and H2O2 during the first phase. The time before initiation of the second phase is inversely correlated with the ciprofloxacin concentration. The second phase is SOS-dependent and characterized by respiratory inhibition, membrane depolarization, K+ and glutathione leakage and cessation of glucose consumption and may be considered as cell death. atpA, gshA and kefBkefC knockouts, which perturb fluxes of protons and K+, can modify the degree and duration of respiratory inhibition and potassium retention. Loss of K+ efflux channels KefB and KefC enhances the susceptibility of E. coli to ciprofloxacin.
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Affiliation(s)
- Galina V Smirnova
- Institute of Ecology and Genetics of Microorganisms, Russian Academy of Sciences, ul. Goleva 13, Perm, 614081, Russia.
| | - Aleksey V Tyulenev
- Institute of Ecology and Genetics of Microorganisms, Russian Academy of Sciences, ul. Goleva 13, Perm, 614081, Russia.
| | - Nadezda G Muzyka
- Institute of Ecology and Genetics of Microorganisms, Russian Academy of Sciences, ul. Goleva 13, Perm, 614081, Russia.
| | - Mikhail A Peters
- Institute of Ecology and Genetics of Microorganisms, Russian Academy of Sciences, ul. Goleva 13, Perm, 614081, Russia.
| | - Oleg N Oktyabrsky
- Institute of Ecology and Genetics of Microorganisms, Russian Academy of Sciences, ul. Goleva 13, Perm, 614081, Russia; Department of Chemistry and Biotechnology, Perm National Research Polytechnic University, Komsomolsky pr., 29, Perm, 614990, Russia.
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162
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Duggirala S, Napoleon JV, Nankar RP, Senu Adeeba V, Manheri MK, Doble M. FtsZ inhibition and redox modulation with one chemical scaffold: Potential use of dihydroquinolines against mycobacteria. Eur J Med Chem 2016; 123:557-567. [PMID: 27517804 DOI: 10.1016/j.ejmech.2016.07.058] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Revised: 07/20/2016] [Accepted: 07/23/2016] [Indexed: 12/15/2022]
Abstract
The dual effect of FtsZ inhibition and oxidative stress by a group of 1,2-dihydroquinolines that culminate in bactericidal effect on mycobacterium strains is demonstrated. They inhibited the non-pathogenic Mycobacterium smegmatis mc(2) 155 with MIC as low as 0.9 μg/mL and induced filamentation. Detailed studies revealed their ability to inhibit polymerization and GTPase activity of MtbFtsZ (Mycobacterial filamentous temperature sensitive Z) with an IC50 value of ∼40 μM. In addition to such target specific effects, these compounds exerted a global cellular effect by causing redox-imbalance that was evident from overproduction of ROS in treated cells. Such multi-targeting effect with one chemical scaffold has considerable significance in this era of emerging drug resistance and could offer promise in the development of new therapeutic agents against tuberculosis.
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Affiliation(s)
- Sridevi Duggirala
- Bioengineering and Drug Design Lab, Department of Biotechnology, Indian Institute of Technology Madras, Chennai, 600 036, India
| | - John Victor Napoleon
- Department of Chemistry, Indian Institute of Technology Madras, Chennai, 600 036, India
| | - Rakesh P Nankar
- Bioengineering and Drug Design Lab, Department of Biotechnology, Indian Institute of Technology Madras, Chennai, 600 036, India
| | - V Senu Adeeba
- Department of Chemistry, Indian Institute of Technology Madras, Chennai, 600 036, India
| | | | - Mukesh Doble
- Bioengineering and Drug Design Lab, Department of Biotechnology, Indian Institute of Technology Madras, Chennai, 600 036, India.
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163
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Dimethyl Sulfoxide Protects Escherichia coli from Rapid Antimicrobial-Mediated Killing. Antimicrob Agents Chemother 2016; 60:5054-8. [PMID: 27246776 DOI: 10.1128/aac.03003-15] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 05/22/2016] [Indexed: 11/20/2022] Open
Abstract
The contribution of reactive oxygen species (ROS) to antimicrobial lethality was examined by treating Escherichia coli with dimethyl sulfoxide (DMSO), an antioxidant solvent frequently used in antimicrobial studies. DMSO inhibited killing by ampicillin, kanamycin, and two quinolones and had little effect on MICs. DMSO-mediated protection correlated with decreased ROS accumulation and provided evidence for ROS-mediated programmed cell death. These data support the contribution of ROS to antimicrobial lethality and suggest caution when using DMSO-dissolved antimicrobials for short-time killing assays.
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164
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Abstract
DNA gyrase and topoisomerase IV are type IIA bacterial topoisomerases that are targeted by highly effective antibiotics. However, resistance via multiple mechanisms arises to limit the efficacies of these drugs. Continued research on type IIA bacterial topoisomerases has provided novel approaches to counter the most common resistance mechanism for utilization of these proven targets in antibacterial therapy. Bacterial topoisomerase I is being explored as an alternative target that is not expected to show cross-resistance. Dual targeting or combination therapy could be strategies for circumventing the development of resistance to topoisomerase-targeting antibiotics. Bacterial topoisomerases are high-value bactericidal targets that could continue to be exploited for antibacterial therapy, if new tactics to counter resistance can be adopted.
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165
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Duan X, Huang X, Wang X, Yan S, Guo S, Abdalla AE, Huang C, Xie J. l-Serine potentiates fluoroquinolone activity against Escherichia coli by enhancing endogenous reactive oxygen species production. J Antimicrob Chemother 2016; 71:2192-9. [PMID: 27118777 DOI: 10.1093/jac/dkw114] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 03/08/2016] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The increase in multiple antimicrobial-resistant bacteria seriously threatens global public health. Novel effective strategies are urgently needed. l-Serine was reported as the most effective amino acid inhibitor against bacterial growth and can sensitize Escherichia coli cells to gentamicin. It is currently unknown whether l-serine affects other type of antibiotics such as β-lactams and fluoroquinolones. METHODS Using E. coli, we studied the combination of l-serine with diverse antibiotics against laboratory and clinical E. coli cultures and persisters. The intracellular NAD(+)/NADH level and ROS were determined using kits. Total cellular iron was determined by using a colorimetric ferrozine-based assay. RESULTS Exogenous l-serine sensitized E. coli ATCC 25922 and clinically isolated fluoroquinolone-resistant E. coli to fluoroquinolones. This potentiation is independent of growth phase. Addition of serine increases the production of NADH. The underlying mechanism of this strategy is that the combination of serine with ofloxacin or moxifloxacin increases the NAD(+)/NADH ratio, disrupts the Fe-S clusters and increases the production of endogenous reactive oxygen species. Furthermore, we used a serine and ofloxacin or moxifloxacin combination in vitro to combat bacterial persister cells, compared with antibiotic treatment alone; combinational treatments of persister cells with antibiotics and l-serine resulted in a significantly greater decrease in cell viability. CONCLUSIONS To our knowledge, this is the first report that l-serine can potentiate the action of ofloxacin or moxifloxacin against Gram-negative bacteria and could constitute a new strategy for the eradication of bacterial infections.
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Affiliation(s)
- Xiangke Duan
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-Environment Three Gorges Reservoir, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Xue Huang
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-Environment Three Gorges Reservoir, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Xiaoyu Wang
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-Environment Three Gorges Reservoir, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Shuangquan Yan
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-Environment Three Gorges Reservoir, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Siyao Guo
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-Environment Three Gorges Reservoir, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China Hanhong College, Southwest University, Chongqing 400715, China
| | - Abualgasim Elgaili Abdalla
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-Environment Three Gorges Reservoir, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China Department of Clinical Microbiology, College of Medical Laboratory Sciences, Omdurman Islamic University, Omdurman, Khartoum, Sudan
| | - Changwu Huang
- The Fifth People's Hospital of Chongqing, Chongqing 400715, China
| | - Jianping Xie
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-Environment Three Gorges Reservoir, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China
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166
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Monteiro R, Hébraud M, Chafsey I, Poeta P, Igrejas G. How different is the proteome of the extended spectrum β-lactamase producing Escherichia coli strains from seagulls of the Berlengas natural reserve of Portugal? J Proteomics 2016; 145:167-176. [PMID: 27118263 DOI: 10.1016/j.jprot.2016.04.032] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Revised: 04/18/2016] [Accepted: 04/20/2016] [Indexed: 01/19/2023]
Abstract
UNLABELLED β-Lactam antibiotics like cefotaxime are the most commonly used antibacterial agents. Escherichia coli strains 5A, 10A, 12A and 23B isolated from Seagulls feces, are cefotaxime-resistant strains that produces extended-spectrum beta-lactamases. Bacterial resistance to these antibiotics occurs predominantly through structural modification on the penicillin-binding proteins and enzymatic inactivation by extended-spectrum β-lactamases. Using classical proteomic techniques (2D-GE) coupled to mass spectrometry and bioinformatics extended analysis, in this study, we report several significant differences in cytoplasmic proteins expression when the strains were submitted to antibiotic stress and when the resistant strains were compared with a non-resistant strain. A total of 79 differentially expressed spots were collected for protein identification. Significant level of expression was found in antibiotic resistant proteins like β-lactamase CTX-M-1 and TEM and also in proteins related with oxidative stress. This approach might help us understand which pathways form barriers for antibiotics, another possible new pathways involved in antibiotic resistance to devise appropriate strategies for their control already recognized by the World Health Organization and the European Commission. BIOLOGICAL SIGNIFICANCE This study highlights the protein differences when a resistant strain is under antibiotic pressure and how different can be a sensible and resistant strain at the protein level. This survey might help us to understand the specifics barriers for antibiotics and which pathways are involved in its resistance crosswise the wildlife.
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Affiliation(s)
- R Monteiro
- Functional Genomics and Proteomics Unit, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal; Department of Genetics and Biotechnology, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal
| | - M Hébraud
- UR454 Microbiology, Institut National de la Recherche Agronomique (INRA), Centre Auvergne-Rhône-Alpes, site de Theix, Saint-Genès Champanelle, France; Plate-Forme d'Exploration du Métabolisme composante protéomique, UR370 QuaPA, Institut National de la Recherche Agronomique (INRA), Centre Auvergne-Rhône-Alpes, site de Theix, Saint-Genès Champanelle, France
| | - I Chafsey
- UR454 Microbiology, Institut National de la Recherche Agronomique (INRA), Centre Auvergne-Rhône-Alpes, site de Theix, Saint-Genès Champanelle, France
| | - P Poeta
- Veterinary Science Department, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal; UCIBIO-REQUIMTE, Faculty of Science and Technology, University NOVA of Lisbon, Caparica, Portugal
| | - G Igrejas
- Functional Genomics and Proteomics Unit, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal; Department of Genetics and Biotechnology, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal; UCIBIO-REQUIMTE, Faculty of Science and Technology, University NOVA of Lisbon, Caparica, Portugal.
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167
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Antibacterial activity of curcumin via apoptosis-like response in Escherichia coli. Appl Microbiol Biotechnol 2016; 100:5505-14. [PMID: 26960318 DOI: 10.1007/s00253-016-7415-x] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 02/21/2016] [Accepted: 02/24/2016] [Indexed: 10/22/2022]
Abstract
Curcumin, a naturally occurring phenolic compound, has been shown to exhibit antimicrobial activity against Candida albicans, Escherichia coli, Pseudomonas aeruginosa, etc., but the mechanism remains unclear. The present study was designed to investigate the novel antibacterial mechanism of curcumin that shows an apoptosis-like response in E. coli. We found that curcumin induces membrane damage at relatively high concentrations, but there was no effect at the minimum inhibitory concentration (MIC). At the MIC, curcumin-treated cells displayed various apoptotic markers such as reactive oxygen species (ROS) accumulation, membrane depolarization, and Ca(2+) influx. Expression of RecA protein, which mediates a bacterial apoptosis-like response, was also increased by curcumin. In order to evaluate the influence of RecA on the appearance of other apoptotic markers, phosphatidylserine (PS) exposure and DNA fragmentation were examined and compared with a RecA deletion strain (ΔRecA). These markers were detected in E. coli wild-type cells, but not in ΔRecA cells. In conclusion, our data demonstrate that curcumin induces an apoptosis-like response in E. coli that involves RecA.
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168
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Ezraty B, Barras F. The ‘liaisons dangereuses’ between iron and antibiotics. FEMS Microbiol Rev 2016; 40:418-35. [DOI: 10.1093/femsre/fuw004] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/27/2016] [Indexed: 12/15/2022] Open
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169
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Kottur J, Nair DT. Reactive Oxygen Species Play an Important Role in the Bactericidal Activity of Quinolone Antibiotics. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201509340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Jithesh Kottur
- Regional Centre for Biotechnology; NCR Biotech Science Cluster; 3rd Milestone, Faridabad-Gurgaon Expressway Faridabad 121001 India
- Manipal University, Madhav Nagar; Manipal 576104 India
| | - Deepak T. Nair
- Regional Centre for Biotechnology; NCR Biotech Science Cluster; 3rd Milestone, Faridabad-Gurgaon Expressway Faridabad 121001 India
- National Centre for Biological Sciences, NCBS-TIFR, GKVK Campus; Bangalore 560065 India
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170
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Kottur J, Nair DT. Reactive Oxygen Species Play an Important Role in the Bactericidal Activity of Quinolone Antibiotics. Angew Chem Int Ed Engl 2016; 55:2397-400. [PMID: 26757158 DOI: 10.1002/anie.201509340] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 11/23/2015] [Indexed: 11/10/2022]
Abstract
Recent studies posit that reactive oxygen species (ROS) contribute to the cell lethality of bactericidal antibiotics. However, this conjecture has been challenged and remains controversial. To resolve this controversy, we adopted a strategy that involves DNA polymerase IV (PolIV). The nucleotide pool of the cell gets oxidized by ROS and PolIV incorporates the damaged nucleotides (especially 8oxodGTP) into the genome, which results in death of the bacteria. By using a combination of structural and biochemical tools coupled with growth assays, it was shown that selective perturbation of the 8oxodGTP incorporation activity of PolIV results in considerable enhancement of the survival of bacteria in the presence of the norfloxacin antibiotic. Our studies therefore indicate that ROS induced in bacteria by the presence of antibiotics in the environment contribute significantly to cell lethality.
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Affiliation(s)
- Jithesh Kottur
- Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, 121001, India.,Manipal University, Madhav Nagar, Manipal, 576104, India
| | - Deepak T Nair
- Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, 121001, India. .,National Centre for Biological Sciences, NCBS-TIFR, GKVK Campus, Bangalore, 560065, India.
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171
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Kumar A, Beloglazova N, Bundalovic-Torma C, Phanse S, Deineko V, Gagarinova A, Musso G, Vlasblom J, Lemak S, Hooshyar M, Minic Z, Wagih O, Mosca R, Aloy P, Golshani A, Parkinson J, Emili A, Yakunin AF, Babu M. Conditional Epistatic Interaction Maps Reveal Global Functional Rewiring of Genome Integrity Pathways in Escherichia coli. Cell Rep 2016; 14:648-661. [PMID: 26774489 DOI: 10.1016/j.celrep.2015.12.060] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 11/08/2015] [Accepted: 12/10/2015] [Indexed: 11/27/2022] Open
Abstract
As antibiotic resistance is increasingly becoming a public health concern, an improved understanding of the bacterial DNA damage response (DDR), which is commonly targeted by antibiotics, could be of tremendous therapeutic value. Although the genetic components of the bacterial DDR have been studied extensively in isolation, how the underlying biological pathways interact functionally remains unclear. Here, we address this by performing systematic, unbiased, quantitative synthetic genetic interaction (GI) screens and uncover widespread changes in the GI network of the entire genomic integrity apparatus of Escherichia coli under standard and DNA-damaging growth conditions. The GI patterns of untreated cultures implicated two previously uncharacterized proteins (YhbQ and YqgF) as nucleases, whereas reorganization of the GI network after DNA damage revealed DDR roles for both annotated and uncharacterized genes. Analyses of pan-bacterial conservation patterns suggest that DDR mechanisms and functional relationships are near universal, highlighting a modular and highly adaptive genomic stress response.
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Affiliation(s)
- Ashwani Kumar
- Department of Computer Science, University of Regina, Regina, SK S4S 0A2, Canada
| | - Natalia Beloglazova
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON M5S 3E5, Canada
| | - Cedoljub Bundalovic-Torma
- Hospital for Sick Children, 686 Bay Street, Toronto, ON M5G OX4, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Sadhna Phanse
- Terrence Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Biochemistry, University of Regina, Regina, SK S4S 0A2, Canada
| | - Viktor Deineko
- Department of Biochemistry, University of Regina, Regina, SK S4S 0A2, Canada
| | - Alla Gagarinova
- Terrence Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Biochemistry, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
| | - Gabriel Musso
- Department of Medicine, Harvard Medical School and Cardiovascular Division, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - James Vlasblom
- Department of Biochemistry, University of Regina, Regina, SK S4S 0A2, Canada
| | - Sofia Lemak
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON M5S 3E5, Canada
| | - Mohsen Hooshyar
- Department of Biology, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Zoran Minic
- Department of Biochemistry, University of Regina, Regina, SK S4S 0A2, Canada
| | - Omar Wagih
- Terrence Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Roberto Mosca
- Joint IRB-BSC-CRG Program in Computational Biology, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, c/Baldiri i Reixac 10-12, Barcelona, 08028, Catalonia, Spain
| | - Patrick Aloy
- Joint IRB-BSC-CRG Program in Computational Biology, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, c/Baldiri i Reixac 10-12, Barcelona, 08028, Catalonia, Spain; Institució Catalana de Recerca i Estudis Avançats (ICREA), Pg. Lluís Companys 23, Barcelona, 08010, Catalonia, Spain
| | - Ashkan Golshani
- Department of Biology, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - John Parkinson
- Hospital for Sick Children, 686 Bay Street, Toronto, ON M5G OX4, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Andrew Emili
- Terrence Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Alexander F Yakunin
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON M5S 3E5, Canada
| | - Mohan Babu
- Department of Biochemistry, University of Regina, Regina, SK S4S 0A2, Canada.
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172
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Lunov O, Zablotskii V, Churpita O, Jäger A, Polívka L, Syková E, Dejneka A, Kubinová Š. The interplay between biological and physical scenarios of bacterial death induced by non-thermal plasma. Biomaterials 2015; 82:71-83. [PMID: 26761777 DOI: 10.1016/j.biomaterials.2015.12.027] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 12/19/2015] [Indexed: 02/06/2023]
Abstract
Direct interactions of plasma matter with living cells and tissues can dramatically affect their functionality, initiating many important effects from cancer elimination to bacteria deactivation. However, the physical mechanisms and biochemical pathways underlying the effects of non-thermal plasma on bacteria and cell fate have still not been fully explored. Here, we report on the molecular mechanisms of non-thermal plasma-induced bacteria inactivation in both Gram-positive and Gram-negative strains. We demonstrate that depending on the exposure time plasma induces either direct physical destruction of bacteria or triggers programmed cell death (PCD) that exhibits characteristic features of apoptosis. The interplay between physical disruption and PCD is on the one hand driven by physical plasma parameters, and on the other hand by biological and physical properties of bacteria. The explored possibilities of the tuneable bacteria deactivation provide a basis for the development of advanced plasma-based therapies. To a great extent, our study opens new possibilities for controlled non-thermal plasma interactions with living systems.
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Affiliation(s)
- Oleg Lunov
- Institute of Physics AS CR, Prague, Czech Republic.
| | | | | | - Ales Jäger
- Institute of Physics AS CR, Prague, Czech Republic
| | - Leoš Polívka
- Institute of Physics AS CR, Prague, Czech Republic
| | - Eva Syková
- Institute of Experimental Medicine AS CR, Prague, Czech Republic
| | | | - Šárka Kubinová
- Institute of Physics AS CR, Prague, Czech Republic; Institute of Experimental Medicine AS CR, Prague, Czech Republic
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173
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Kohanski MA, Tharakan A, Lane AP, Ramanathan M. Bactericidal antibiotics promote reactive oxygen species formation and inflammation in human sinonasal epithelial cells. Int Forum Allergy Rhinol 2015; 6:191-200. [PMID: 26624249 DOI: 10.1002/alr.21646] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 07/29/2015] [Accepted: 08/11/2015] [Indexed: 12/12/2022]
Abstract
BACKGROUND Bactericidal antibiotics have been shown to stimulate reactive oxygen species (ROS) formation in mammalian cells through mitochondrial dysfunction. This results in oxidative tissue damage that may have negative consequences for long-term antibiotic use. Antibiotics are widely and heavily used in the treatment of acute and chronic sinusitis; however, the relationship between antibiotics and ROS formation in sinonasal epithelial cells (SNECs) has not yet been demonstrated. METHODS Human SNECs were collected from patients during endoscopic sinus surgery and grown in culture at the air-liquid interface. Differentiated SNECs were stimulated with the bactericidal antibiotics amoxicillin and levofloxacin and the bacteriostatic antibiotic clarithromycin for 24 hours. ROS were quantified via fluorescence. Cell death was quantified by lactate dehydrogenase (LDH) secretion. Expression of inflammatory markers such as tumor necrosis factor α (TNF-α) and nuclear factor erythroid 2-related factor 2 (Nrf2)-mediated antioxidant genes were measured by real-time polymerase chain reaction (RT-PCR). RESULTS Cultured SNECs treated with the bactericidal antibiotics amoxicillin and levofloxacin resulted in a significant increase in production of ROS (p < 0.05) and secretion of LDH (p < 0.05). The increase in ROS formation correlated with an increase in expression of Nrf2-mediated antioxidant genes as well as the expression and production of proinflammatory cytokine TNF-α, and interleukin 1 β (IL-1β) (p < 0.05). SNECs treated with clarithromycin did not demonstrate statistically significant increases in ROS or proinflammatory cytokine production. CONCLUSION In this study, we show that treatment of cultured human SNECs with bactericidal antibiotics leads to formation of ROS with an associated increase in inflammatory and antioxidant gene expression and cell death. This suggests that long-term or inappropriate antibiotic use in the treatment of sinusitis may result in oxidative tissue damage to the sinonasal epithelium. Future studies will explore the clinical implications of such damage to the sinonasal epithelium.
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Affiliation(s)
- Michael A Kohanski
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Anuj Tharakan
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Andrew P Lane
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Murugappan Ramanathan
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD
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174
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Oung HM, Lin KC, Wu TM, Chandrika NNP, Hong CY. Hygromycin B-induced cell death is partly mediated by reactive oxygen species in rice (Oryza sativa L.). PLANT MOLECULAR BIOLOGY 2015; 89:577-588. [PMID: 26415870 DOI: 10.1007/s11103-015-0380-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 09/15/2015] [Indexed: 06/05/2023]
Abstract
The aminoglycoside antibiotic hygromycin B (Hyg) inhibits prokaryotic, chloroplast and mitochondrial protein synthesis. Because of the toxic effect of Hyg on plant cells, the HPT gene, encoding hygromycin phosphotransferase, has become one of the most widely used selectable markers in plant transformation. Yet the mechanism behind Hyg-induced cell lethality in plants is not clearly understood. In this study, we aimed to decipher this mechanism. With Hyg treatment, rice calli exhibited cell death, and rice seedlings showed severe growth defects, leaf chlorosis and leaf shrinkage. Rice seedlings also exhibited severe lipid peroxidation and protein carbonylation, for oxidative stress damage at the cellular level. The production of reactive oxygen species such as O2(·-), H2O2 and OH(·) was greatly induced in rice seedlings under Hyg stress, and pre-treatment with ascorbate increased resistance to Hyg-induced toxicity indicating the existence of oxidative stress. Overexpression of mitochondrial Alternative oxidase1a gene without HPT selection marker in rice enhanced tolerance to Hyg and attenuated the degradation of protein content, whereas the rice plastidial glutathione reductase 3 mutant showed increased sensitivity to Hyg. These results demonstrate that Hyg-induced cell lethality in rice is not only due to the inhibition of protein synthesis but also mediated by oxidative stress.
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Affiliation(s)
- Hui-Min Oung
- Department of Agricultural Chemistry, College of Bioresources and Agriculture, National Taiwan University, Taipei, 10617, Taiwan
| | - Ke-Chun Lin
- Department of Agricultural Chemistry, College of Bioresources and Agriculture, National Taiwan University, Taipei, 10617, Taiwan
| | - Tsung-Meng Wu
- Department of Agricultural Chemistry, College of Bioresources and Agriculture, National Taiwan University, Taipei, 10617, Taiwan
- Department of Aquaculture, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan
| | - Nulu Naga Prafulla Chandrika
- Department of Agricultural Chemistry, College of Bioresources and Agriculture, National Taiwan University, Taipei, 10617, Taiwan
| | - Chwan-Yang Hong
- Department of Agricultural Chemistry, College of Bioresources and Agriculture, National Taiwan University, Taipei, 10617, Taiwan.
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175
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Mora-Pale M, Bhan N, Masuko S, James P, Wood J, McCallum S, Linhardt RJ, Dordick JS, Koffas MAG. Antimicrobial mechanism of resveratrol-trans-dihydrodimer produced from peroxidase-catalyzed oxidation of resveratrol. Biotechnol Bioeng 2015; 112:2417-28. [PMID: 26109045 DOI: 10.1002/bit.25686] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 05/11/2015] [Accepted: 06/15/2015] [Indexed: 12/15/2022]
Abstract
Plant polyphenols are known to have varying antimicrobial potencies, including direct antibacterial activity, synergism with antibiotics and suppression of bacterial virulence. We performed the in vitro oligomerization of resveratrol catalyzed by soybean peroxidase, and the two isomers (resveratrol-trans-dihydrodimer and pallidol) produced were tested for antimicrobial activity. The resveratrol-trans-dihydrodimer displayed antimicrobial activity against the Gram-positive bacteria Bacillus cereus, Listeria monocytogenes, and Staphylococcus aureus (minimum inhibitory concentration (MIC) = 15.0, 125, and 62.0 μM, respectively) and against Gram-negative Escherichia coli (MIC = 123 μM, upon addition of the efflux pump inhibitor Phe-Arg-β-naphthylamide). In contrast, pallidol had no observable antimicrobial activity against all tested strains. Transcriptomic analysis implied downregulation of ABC transporters, genes involved in cell division and DNA binding proteins. Flow cytometric analysis of treated cells revealed a rapid collapse in membrane potential and a substantial decrease in total DNA content. The active dimer showed >90% inhibition of DNA gyrase activity, in vitro, by blocking the ATP binding site of the enzyme. We thus propose that the resveratrol-trans-dihydrodimer acts to: (1) disrupt membrane potential; and (2) inhibit DNA synthesis. In summary, we introduce the mechanisms of action and the initial evaluation of an active bactericide, and a platform for the development of polyphenolic antimicrobials.
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Affiliation(s)
- Mauricio Mora-Pale
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Center for Biotechnology and Interdisciplinary Studies, Troy, New York, 12180-3590
| | - Namita Bhan
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Center for Biotechnology and Interdisciplinary Studies, Troy, New York, 12180-3590
| | - Sayaka Masuko
- Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Center for Biotechnology and Interdisciplinary Studies, Troy, New York
| | - Paul James
- Henry Wellcome Building for Biocatalysis, Biosciences, College of Life and Environmental Science, University of Exeter, Exeter, Devon
| | - Julia Wood
- Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Center for Biotechnology and Interdisciplinary Studies, Troy, New York
| | - Scott McCallum
- NMR Core Facility, Rensselaer Polytechnic Institute, Center for Biotechnology and Interdisciplinary Studies, Troy, New York
| | - Robert J Linhardt
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Center for Biotechnology and Interdisciplinary Studies, Troy, New York, 12180-3590
- Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Center for Biotechnology and Interdisciplinary Studies, Troy, New York
- Department of Biology, Rensselaer Polytechnic Institute, Center for Biotechnology and Interdisciplinary Studies, Troy, New York
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Center for Biotechnology and Interdisciplinary Studies, Troy, New York
| | - Jonathan S Dordick
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Center for Biotechnology and Interdisciplinary Studies, Troy, New York, 12180-3590.
- Department of Biology, Rensselaer Polytechnic Institute, Center for Biotechnology and Interdisciplinary Studies, Troy, New York.
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Center for Biotechnology and Interdisciplinary Studies, Troy, New York.
- Department of Material Science and Engineering, Rensselaer Polytechnic Institute, Center for Biotechnology and Interdisciplinary Studies, Troy, New York.
| | - Mattheos A G Koffas
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Center for Biotechnology and Interdisciplinary Studies, Troy, New York, 12180-3590.
- Department of Biology, Rensselaer Polytechnic Institute, Center for Biotechnology and Interdisciplinary Studies, Troy, New York.
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176
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Neissa J, Pérez-Arnaiz C, Porto V, Busto N, Borrajo E, Leal JM, López-Quintela MA, García B, Dominguez F. Interaction of silver atomic quantum clusters with living organisms: bactericidal effect of Ag 3 clusters mediated by disruption of topoisomerase-DNA complexes. Chem Sci 2015; 6:6717-6724. [PMID: 29861921 PMCID: PMC5950836 DOI: 10.1039/c5sc02022k] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 07/13/2015] [Indexed: 11/21/2022] Open
Abstract
Essential processes for living cells such as transcription and replication depend on the formation of specific protein-DNA recognition complexes. Proper formation of such complexes requires suitable fitting between the protein surface and the DNA surface. By adopting doxorubicin (DOX) as a model probe, we report here that Ag3 atomic quantum clusters (Ag-AQCs) inhibit the intercalation of DOX into DNA and have considerable influence on the interaction of DNA-binding proteins such as topoisomerase IV, Escherichia coli DNA gyrase and the restriction enzyme HindIII. Ag-AQCs at nanomolar concentrations inhibit enzyme activity. The inhibitory effect of Ag-AQCs is dose-dependent and occurs by intercalation into DNA. All these effects, not observed in the presence of Ag+ ions, can explain the powerful bactericidal activity of Ag-AQCs, extending the knowledge of silver bactericidal properties. Lastly, we highlight the interest of the interaction of Ag clusters with living organisms, an area that should be further explored due to the potential consequences that it might have, both beneficial and harmful.
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Affiliation(s)
- J Neissa
- Department of Physiology and Centro de Investigaciones en Medicina Molecular y Enfermedades Crónicas (CIMUS) , University of Santiago de Compostela , E-15782 Santiago de Compostela , Spain .
| | - C Pérez-Arnaiz
- Department of Chemistry , University of Burgos , E-9001 Burgos , Spain .
| | - V Porto
- Department of Physiology and Centro de Investigaciones en Medicina Molecular y Enfermedades Crónicas (CIMUS) , University of Santiago de Compostela , E-15782 Santiago de Compostela , Spain .
| | - N Busto
- Department of Chemistry , University of Burgos , E-9001 Burgos , Spain .
| | - E Borrajo
- Department of Physiology and Centro de Investigaciones en Medicina Molecular y Enfermedades Crónicas (CIMUS) , University of Santiago de Compostela , E-15782 Santiago de Compostela , Spain .
| | - J M Leal
- Department of Chemistry , University of Burgos , E-9001 Burgos , Spain .
| | - M A López-Quintela
- Department of Physical Chemistry , Fac. Chemistry and Nanomag Laboratory , IIT. University of Santiago de Compostela , E-15782 Santiago de Compostela , Spain
| | - B García
- Department of Chemistry , University of Burgos , E-9001 Burgos , Spain .
| | - F Dominguez
- Department of Physiology and Centro de Investigaciones en Medicina Molecular y Enfermedades Crónicas (CIMUS) , University of Santiago de Compostela , E-15782 Santiago de Compostela , Spain .
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177
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Reactive Oxygen Species Contribute to the Bactericidal Effects of the Fluoroquinolone Moxifloxacin in Streptococcus pneumoniae. Antimicrob Agents Chemother 2015; 60:409-17. [PMID: 26525786 DOI: 10.1128/aac.02299-15] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 10/24/2015] [Indexed: 11/20/2022] Open
Abstract
We studied the transcriptomic response of Streptococcus pneumoniae to the fluoroquinolone moxifloxacin at a concentration that inhibits DNA gyrase. Treatment of the wild-type strain R6, at a concentration of 10× the MIC, triggered a response involving 132 genes after 30 min of treatment. Genes from several metabolic pathways involved in the production of pyruvate were upregulated. These included 3 glycolytic enzymes, which ultimately convert fructose 6-phosphate to pyruvate, and 2 enzymes that funnel phosphate sugars into the glycolytic pathway. In addition, acetyl coenzyme A (acetyl-CoA) carboxylase was downregulated, likely leading to an increase in acetyl-CoA. When coupled with an upregulation in formate acetyltransferase, an increase in acetyl-CoA would raise the production of pyruvate. Since pyruvate is converted by pyruvate oxidase (SpxB) into hydrogen peroxide (H2O2), an increase in pyruvate would augment intracellular H2O2. Here, we confirm a 21-fold increase in the production of H2O2 and a 55-fold increase in the amount of hydroxyl radical in cultures treated during 4 h with moxifloxacin. This increase in hydroxyl radical through the Fenton reaction would damage DNA, lipids, and proteins. These reactive oxygen species contributed to the lethality of the drug, a conclusion supported by the observed protective effects of an SpxB deletion. These results support the model whereby fluoroquinolones cause redox alterations. The transcriptional response of S. pneumoniae to moxifloxacin is compared with the response to levofloxacin, an inhibitor of topoisomerase IV. Levofloxacin triggers the transcriptional activation of iron transport genes and also enhances the Fenton reaction.
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178
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Belenky P, Ye JD, Porter CBM, Cohen NR, Lobritz MA, Ferrante T, Jain S, Korry BJ, Schwarz EG, Walker GC, Collins JJ. Bactericidal Antibiotics Induce Toxic Metabolic Perturbations that Lead to Cellular Damage. Cell Rep 2015; 13:968-80. [PMID: 26565910 DOI: 10.1016/j.celrep.2015.09.059] [Citation(s) in RCA: 320] [Impact Index Per Article: 35.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 09/04/2015] [Accepted: 09/17/2015] [Indexed: 01/16/2023] Open
Abstract
Understanding how antibiotics impact bacterial metabolism may provide insight into their mechanisms of action and could lead to enhanced therapeutic methodologies. Here, we profiled the metabolome of Escherichia coli after treatment with three different classes of bactericidal antibiotics (?-lactams, aminoglycosides, quinolones). These treatments induced a similar set of metabolic changes after 30 min that then diverged into more distinct profiles at later time points. The most striking changes corresponded to elevated concentrations of central carbon metabolites, active breakdown of the nucleotide pool, reduced lipid levels, and evidence of an elevated redox state. We examined potential end-target consequences of these metabolic perturbations and found that antibiotic-treated cells exhibited cytotoxic changes indicative of oxidative stress, including higher levels of protein carbonylation, malondialdehyde adducts, nucleotide oxidation, and double-strand DNA breaks. This work shows that bactericidal antibiotics induce a complex set of metabolic changes that are correlated with the buildup of toxic metabolic by-products.
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Affiliation(s)
- Peter Belenky
- Department of Biomedical Engineering and Center of Synthetic Biology, Boston University, 36 Cummington Mall, Boston, MA 02215, USA; Department of Molecular Microbiology and Immunology, Brown University, 171 Meeting Street, Providence, RI 02912, USA.
| | - Jonathan D Ye
- Department of Biomedical Engineering and Center of Synthetic Biology, Boston University, 36 Cummington Mall, Boston, MA 02215, USA
| | - Caroline B M Porter
- Institute for Medical Engineering & Science, Department of Biological Engineering, and Synthetic Biology Center, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, MA 02142, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, 3 Blackfan Circle, Boston, MA 02115, USA
| | - Nadia R Cohen
- Institute for Medical Engineering & Science, Department of Biological Engineering, and Synthetic Biology Center, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, 3 Blackfan Circle, Boston, MA 02115, USA
| | - Michael A Lobritz
- Institute for Medical Engineering & Science, Department of Biological Engineering, and Synthetic Biology Center, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, MA 02142, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, 3 Blackfan Circle, Boston, MA 02115, USA; Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA 02115, USA
| | - Thomas Ferrante
- Wyss Institute for Biologically Inspired Engineering, Harvard University, 3 Blackfan Circle, Boston, MA 02115, USA
| | - Saloni Jain
- Department of Biomedical Engineering and Center of Synthetic Biology, Boston University, 36 Cummington Mall, Boston, MA 02215, USA; Institute for Medical Engineering & Science, Department of Biological Engineering, and Synthetic Biology Center, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Benjamin J Korry
- Department of Molecular Microbiology and Immunology, Brown University, 171 Meeting Street, Providence, RI 02912, USA
| | - Eric G Schwarz
- Department of Biomedical Engineering and Center of Synthetic Biology, Boston University, 36 Cummington Mall, Boston, MA 02215, USA
| | - Graham C Walker
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - James J Collins
- Institute for Medical Engineering & Science, Department of Biological Engineering, and Synthetic Biology Center, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA; Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, MA 02142, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, 3 Blackfan Circle, Boston, MA 02115, USA.
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179
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Influence of Moxifloxacin on Hepatic Redox Status and Plasma Biomarkers of Hepatotoxicity and Nephrotoxicity in Rat. Biochem Res Int 2015; 2015:192724. [PMID: 26550491 PMCID: PMC4621322 DOI: 10.1155/2015/192724] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 09/20/2015] [Indexed: 01/18/2023] Open
Abstract
Moxifloxacin is a broad spectrum fluoroquinolone antibacterial agent. We examined the hepatic redox status and plasma biomarkers of nephrotoxicity and hepatotoxicity in rat following administration of moxifloxacin (MXF). Twenty-four Wistar rats, 180–200 g, were randomized into four groups (I–IV). Animals in group I (control) received 1 mL of distilled water, while animals in groups II, III, and IV received 1 mL each of MXF equivalent to 4 mg/kg b.w., 8 mg/kg b.w., and 16 mg/kg b.w., respectively. After seven days, plasma urea, bilirubin, and creatinine were significantly (P < 0.05) elevated in the MXF-treated animals. Activities of alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase were significantly increased in the plasma of MXF-treated animals compared to control. Also plasma total cholesterol, HDL-cholesterol, LDL-cholesterol, and triglycerides increased significantly in the MXF-treated groups relative to control. Moreover, MXF triggered a significant decrease in hepatic catalase, superoxide dismutase, and glutathione-S transferase activities. Likewise, MXF caused a decrease in the hepatic levels of glutathione and vitamin C. A significant increase in hepatic MDA content was also observed in the MXF-treated animals relative to control. Overall, our data suggest that the half-therapeutic, therapeutic, and twice the therapeutic dose of MXF induced nephrotoxicity, hepatotoxicity, and altered hepatic redox balance in rats.
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180
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Biologically synthesized silver nanoparticles enhances antibiotic activity against Gram-negative bacteria. J IND ENG CHEM 2015. [DOI: 10.1016/j.jiec.2015.04.005] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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181
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Guidry CA, Davies SW, Metzger R, Swenson BR, Sawyer RG. Whence Resistance? Surg Infect (Larchmt) 2015; 16:716-20. [PMID: 26186101 DOI: 10.1089/sur.2014.160] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Antimicrobial resistance results from a complex interaction between pathogenic and non-pathogenic bacteria, antimicrobial pressure, and genes, which together comprise the total body of potential resistance elements. The purpose of this study is to review and evaluate the importance of antimicrobial pressure on the development of resistance in a single surgical intensive care unit. METHODS We reviewed a prospectively collected dataset of all intensive care unit (ICU)-acquired infections in surgical and trauma patients over a 6-y period at a single hospital. Resistant gram-negative pathogens (rGNR) included those resistant to all aminoglycosides, quinolones, penicillins, cephalosporins, or carbapenems; resistant gram-positive infections (rGPC) included methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant enterococci (VRE). Each resistant infection was evaluated for prior or concomitant antibiotic use, previous treatment for the same (non-resistant) organism, and concurrent infection with the same organism (genus and species, although not necessarily resistant) in another ICU patient. RESULTS Three hundred and thirty resistant infections were identified: 237 rGNR and 93 rGPC. Infections with rGNR occurred frequently while receiving antibiotic therapy (65%), including the sensitive form of the subsequent resistant pathogen (42.2%). Infections with rGPC were also likely to occur on antimicrobial therapy (50.6%). Treatment of a different patient for an infection with the same resistant pathogen in the ICU at the time of diagnosis, implying potential patient-to-patient transmission occurred more frequently with rGNR infections (38.8%). CONCLUSION Antimicrobial pressure exerts a substantial effect on the development of subsequent infection. Our data demonstrate a high estimated rate of de novo emergence of resistance after treatment, which appears to be more common than patient-to-patient transmission. These data support the concept that efforts to limit antimicrobial usage will be more efficacious than enhanced isolation procedures when trying to reduce antimicrobial resistance.
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Affiliation(s)
- Christopher A Guidry
- 1 Department of Surgery, The University of Virginia Health System , Charlottesville, Virginia
| | - Stephen W Davies
- 1 Department of Surgery, The University of Virginia Health System , Charlottesville, Virginia
| | - Rosemarie Metzger
- 1 Department of Surgery, The University of Virginia Health System , Charlottesville, Virginia
| | - Brian R Swenson
- 1 Department of Surgery, The University of Virginia Health System , Charlottesville, Virginia
| | - Robert G Sawyer
- 1 Department of Surgery, The University of Virginia Health System , Charlottesville, Virginia.,2 Division of Acute Care and Trauma Surgery, The University of Virginia Health System , Charlottesville, Virginia
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182
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Oliveira NM, Martinez-Garcia E, Xavier J, Durham WM, Kolter R, Kim W, Foster KR. Biofilm Formation As a Response to Ecological Competition. PLoS Biol 2015; 13:e1002191. [PMID: 26158271 PMCID: PMC4497666 DOI: 10.1371/journal.pbio.1002191] [Citation(s) in RCA: 150] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Accepted: 05/29/2015] [Indexed: 12/28/2022] Open
Abstract
Bacteria form dense surface-associated communities known as biofilms that are central to their persistence and how they affect us. Biofilm formation is commonly viewed as a cooperative enterprise, where strains and species work together for a common goal. Here we explore an alternative model: biofilm formation is a response to ecological competition. We co-cultured a diverse collection of natural isolates of the opportunistic pathogen Pseudomonas aeruginosa and studied the effect on biofilm formation. We show that strain mixing reliably increases biofilm formation compared to unmixed conditions. Importantly, strain mixing leads to strong competition: one strain dominates and largely excludes the other from the biofilm. Furthermore, we show that pyocins, narrow-spectrum antibiotics made by other P. aeruginosa strains, can stimulate biofilm formation by increasing the attachment of cells. Side-by-side comparisons using microfluidic assays suggest that the increase in biofilm occurs due to a general response to cellular damage: a comparable biofilm response occurs for pyocins that disrupt membranes as for commercial antibiotics that damage DNA, inhibit protein synthesis or transcription. Our data show that bacteria increase biofilm formation in response to ecological competition that is detected by antibiotic stress. This is inconsistent with the idea that sub-lethal concentrations of antibiotics are cooperative signals that coordinate microbial communities, as is often concluded. Instead, our work is consistent with competition sensing where low-levels of antibiotics are used to detect and respond to the competing genotypes that produce them. Mixing natural isolates of the pathogenic bacterium Pseudomonas aeruginosa shows that the formation of biofilm is a response to antibiotic stress from competing genotypes. Bacteria often attach to each other and to surfaces and make biofilms. These dense communities occur everywhere, including on us and inside us, where they are central to both health and disease. Biofilm formation is often viewed as the coordinated action of multiple strains that work together in order to prosper and protect each other. In this study, we provide evidence for a very different view: biofilms are formed when bacterial strains compete with one another. We mixed together different strains of the widespread pathogen Pseudomonas aeruginosa and found that pairs often make bigger biofilms than either one alone. Rather than working together, however, we show that one strain normally kills the other off and that biofilm formation is actually a response to the damage of antibiotic warfare. Our work helps to explain the widespread observation that treating bacteria with clinical antibiotics can stimulate biofilm formation. When we treat bacteria, they respond as if the attack is coming from a foreign strain that must be outnumbered and outcompeted in a biofilm.
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Affiliation(s)
- Nuno M. Oliveira
- Department of Zoology, University of Oxford, Oxford, United Kingdom
- Oxford Centre for Integrative Systems Biology, University of Oxford, Oxford, United Kingdom
| | - Esteban Martinez-Garcia
- FAS Center for Systems Biology, University of Harvard, Cambridge, Massachusetts, United States of America
- Centro Nacional de Biotecnologia-CSIC, Campus de Cantoblanco, Madrid, Spain
| | - Joao Xavier
- FAS Center for Systems Biology, University of Harvard, Cambridge, Massachusetts, United States of America
- Memorial Sloan-Kettering Cancer Center, Computational Biology Program, New York, New York, United States of America
| | | | - Roberto Kolter
- Harvard Medical School, Department of Microbiology and Immunobiology, Boston, Massachusetts, United States of America
| | - Wook Kim
- Department of Zoology, University of Oxford, Oxford, United Kingdom
- Oxford Centre for Integrative Systems Biology, University of Oxford, Oxford, United Kingdom
- FAS Center for Systems Biology, University of Harvard, Cambridge, Massachusetts, United States of America
| | - Kevin R. Foster
- Department of Zoology, University of Oxford, Oxford, United Kingdom
- Oxford Centre for Integrative Systems Biology, University of Oxford, Oxford, United Kingdom
- FAS Center for Systems Biology, University of Harvard, Cambridge, Massachusetts, United States of America
- * E-mail:
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183
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Zavil’gel’skii GB, Kotova VY, Mironov AS. Lux biosensors for antibiotic detection: The contribution from reactive oxygen species to the bactericidal activity of antibiotics. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY B 2015. [DOI: 10.1134/s1990793115030239] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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184
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Angel Villegas N, Baronetti J, Albesa I, Etcheverría A, Becerra MC, Padola NL, Paraje MG. Effect of antibiotics on cellular stress generated in Shiga toxin-producing Escherichia coli O157:H7 and non-O157 biofilms. Toxicol In Vitro 2015; 29:1692-700. [PMID: 26130220 DOI: 10.1016/j.tiv.2015.06.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 06/25/2015] [Accepted: 06/26/2015] [Indexed: 11/28/2022]
Abstract
Shiga toxin-producing Escherichia coli (STEC) are important food-borne pathogens, with the main virulence factor of this bacterium being its capacity to secrete Shiga toxins (Stxs). Therefore, the use of certain antibiotics for the treatment of this infection, which induces the liberation of Stxs, is controversial. Reactive oxygen and nitrogen species are also involved in the pathogenesis of different diseases. The purpose of this study was to analyze the effects of antibiotics on biofilms of STEC and the relationships between cellular stress and the release of Stx. To this end, biofilms of reference and clinical strains were treated with antibiotics (ciprofloxacin, fosfomycin and rifaximin) and the production of oxidants, the antioxidant defense system and toxin release were evaluated. Ciprofloxacin altered the prooxidant-antioxidant balance, with a decrease of oxidant metabolites and an increase of superoxide dismutase and catalase activity, being associated with high-levels of Stx production. Furthermore, inhibition of oxidative stress by exogenous antioxidants was correlated with a reduction in the liberation of Stx, indicating the participation of this phenomenon in the release of this toxin. In contrast, fosfomycin and rifaximin produced less alteration with a minimal production of Stx. Our data show that treatment of biofilm-STEC with these antibiotics induces oxidative stress-mediated release of Stx.
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Affiliation(s)
- Natalia Angel Villegas
- IMBIV-CONICET y Departamento de Farmacia, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
| | - José Baronetti
- IMBIV-CONICET y Cátedra de Microbiología, Facultad de Ciencias Exactas Físicas y Naturales, Universidad Nacional de Córdoba, Argentina
| | - Inés Albesa
- IMBIV-CONICET y Departamento de Farmacia, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
| | - Analía Etcheverría
- Laboratorio de Inmunoquímica y Biotecnología, Dpto. SAMP, Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires, Tandil, Argentina
| | - M Cecilia Becerra
- IMBIV-CONICET y Departamento de Farmacia, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
| | - Nora L Padola
- Laboratorio de Inmunoquímica y Biotecnología, Dpto. SAMP, Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires, Tandil, Argentina
| | - M Gabriela Paraje
- IMBIV-CONICET y Cátedra de Microbiología, Facultad de Ciencias Exactas Físicas y Naturales, Universidad Nacional de Córdoba, Argentina.
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185
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Antibiotic efficacy is linked to bacterial cellular respiration. Proc Natl Acad Sci U S A 2015; 112:8173-80. [PMID: 26100898 DOI: 10.1073/pnas.1509743112] [Citation(s) in RCA: 457] [Impact Index Per Article: 50.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Bacteriostatic and bactericidal antibiotic treatments result in two fundamentally different phenotypic outcomes--the inhibition of bacterial growth or, alternatively, cell death. Most antibiotics inhibit processes that are major consumers of cellular energy output, suggesting that antibiotic treatment may have important downstream consequences on bacterial metabolism. We hypothesized that the specific metabolic effects of bacteriostatic and bactericidal antibiotics contribute to their overall efficacy. We leveraged the opposing phenotypes of bacteriostatic and bactericidal drugs in combination to investigate their activity. Growth inhibition from bacteriostatic antibiotics was associated with suppressed cellular respiration whereas cell death from most bactericidal antibiotics was associated with accelerated respiration. In combination, suppression of cellular respiration by the bacteriostatic antibiotic was the dominant effect, blocking bactericidal killing. Global metabolic profiling of bacteriostatic antibiotic treatment revealed that accumulation of metabolites involved in specific drug target activity was linked to the buildup of energy metabolites that feed the electron transport chain. Inhibition of cellular respiration by knockout of the cytochrome oxidases was sufficient to attenuate bactericidal lethality whereas acceleration of basal respiration by genetically uncoupling ATP synthesis from electron transport resulted in potentiation of the killing effect of bactericidal antibiotics. This work identifies a link between antibiotic-induced cellular respiration and bactericidal lethality and demonstrates that bactericidal activity can be arrested by attenuated respiration and potentiated by accelerated respiration. Our data collectively show that antibiotics perturb the metabolic state of bacteria and that the metabolic state of bacteria impacts antibiotic efficacy.
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186
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Zhong J, Xiao C, Gu W, Du G, Sun X, He QY, Zhang G. Transfer RNAs Mediate the Rapid Adaptation of Escherichia coli to Oxidative Stress. PLoS Genet 2015; 11:e1005302. [PMID: 26090660 PMCID: PMC4474833 DOI: 10.1371/journal.pgen.1005302] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 05/27/2015] [Indexed: 11/18/2022] Open
Abstract
Translational systems can respond promptly to sudden environmental changes to provide rapid adaptations to environmental stress. Unlike the well-studied translational responses to oxidative stress in eukaryotic systems, little is known regarding how prokaryotes respond rapidly to oxidative stress in terms of translation. In this study, we measured protein synthesis from the entire Escherichia coli proteome and found that protein synthesis was severely slowed down under oxidative stress. With unchanged translation initiation, this slowdown was caused by decreased translation elongation speed. We further confirmed by tRNA sequencing and qRT-PCR that this deceleration was caused by a global, enzymatic downregulation of almost all tRNA species shortly after exposure to oxidative agents. Elevation in tRNA levels accelerated translation and protected E. coli against oxidative stress caused by hydrogen peroxide and the antibiotic ciprofloxacin. Our results showed that the global regulation of tRNAs mediates the rapid adjustment of the E. coli translation system for prompt adaptation to oxidative stress. All organisms need to respond quickly to sudden environmental changes. Translational regulation can occur in response to environmental stresses within minutes, which is much faster than transcriptional regulation, and thus normally provides immediate adaptation. Eukaryotic cells can manipulate their tRNA molecules, mainly in a reversible manner, to suppress translation. Here, we showed for the first time that bacteria respond to oxidative stress by adjusting the translational system in a manner that differs from that of eukaryotes. The bacteria nonspecifically, irreversibly, and enzymatically degrade tRNAs to block protein synthesis. Interestingly, we showed that elevated tRNA concentrations lead to opposing effects by causing increased protein aggregation, which impairs fitness under normal conditions but facilitates adaptation under oxidative stress, including that caused by antibiotics. Our results provide a new understanding of the role of global adjustments to the entire translation system during stress adaptation in bacteria. This mechanism may also be involved in the development of antibiotic resistance in bacteria.
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Affiliation(s)
- Jiayong Zhong
- Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, College of Life Science and Technology, Jinan University, Guangzhou, China
| | - Chuanle Xiao
- Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, College of Life Science and Technology, Jinan University, Guangzhou, China
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Wei Gu
- Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, College of Life Science and Technology, Jinan University, Guangzhou, China
| | - Gaofei Du
- Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, College of Life Science and Technology, Jinan University, Guangzhou, China
| | - Xuesong Sun
- Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, College of Life Science and Technology, Jinan University, Guangzhou, China
| | - Qing-Yu He
- Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, College of Life Science and Technology, Jinan University, Guangzhou, China
- * E-mail: (QYH); (GZ)
| | - Gong Zhang
- Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, College of Life Science and Technology, Jinan University, Guangzhou, China
- * E-mail: (QYH); (GZ)
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187
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Andrukov BG, Somova LM, Timchenko NF. STRATEGY OF PROGRAMMED CELL DEATH IN PROKARYOTES. RUSSIAN JOURNAL OF INFECTION AND IMMUNITY 2015. [DOI: 10.15789/2220-7619-2015-1-15-26] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Programmed cell death (PCD) was first studied in eukaryotic organisms. This system also operates in the development life cycle of prokaryotes. The system PCD in microorganisms is activated a wide range of signals in response to the stresses associated with adverse environmental conditions or exposure to antibacterial agents. The results of numerous studies in the past decade allow considering the system PCD in prokaryotes as an evolutionary conservation of the species. These results significantly expanded understanding of the role of PCD in microorganisms and opened a number of important areas of research of the morphological and molecular genetic approaches to the study of death strategies for the survival in bacterial populations. The purpose of the review is to summarize the morphological and molecular genetic characteristics of PCD in prokaryotes which are real manifestations of the mechanisms of this phenomenon.
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188
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Okamura S, Nishiyama E, Yamazaki T, Otsuka N, Taniguchi S, Ogawa W, Hatano T, Tsuchiya T, Kuroda T. Action mechanism of 6, 6'-dihydroxythiobinupharidine from Nuphar japonicum, which showed anti-MRSA and anti-VRE activities. Biochim Biophys Acta Gen Subj 2015; 1850:1245-52. [PMID: 25731981 DOI: 10.1016/j.bbagen.2015.02.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 02/11/2015] [Accepted: 02/22/2015] [Indexed: 11/17/2022]
Abstract
BACKGROUND Multidrug-resistant bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin resistant enterococci (VRE), cause serious infections at clinical sites, for which the development of new drugs is necessary. We screened candidates for new antibiotics and investigated its action mechanism. METHODS An antimicrobial compound was isolated from an extract of Nuphar japonicum. Its chemical structure was determined by NMR, MS, and optical rotation. We measured its minimum inhibitory concentration (MIC) using the microdilution method. The effects of the compound on DNA gyrase and DNA topoisomerase IV were investigated with DNA supercoiling, decatenation, and cleavage assay. RESULTS We isolated and identified 6,6'-dihydroxythiobinupharidine as the antimicrobial compound. The MIC of this compound was 1-4 μg/mL against various MRSA and VRE strains. We also demonstrated that this compound inhibited DNA topoisomerase IV (IC50 was 10-15 μM), but not DNA gyrase in S. aureus, both of which are known to be the targets of quinolone antibiotics and necessary for DNA replication. However, this compound only exhibited slight cross-resistance to norfloxacin-resistant S. aureus, which indicated that DTBN might inhibit other targets besides topoisomerase IV. These results suggest that 6,6'-dihydroxythiobinupharidine may be a potent candidate or seed for novel antibacterial agents. CONCLUSIONS DTBN from N. japonicum showed anti-MRSA and anti-VRE activities. DTBN might be involved in the inhibition of DNA topoisomerase IV. GENERAL SIGNIFICANCE DTBN might be useful as a seed compound. The information on the inhibition mechanism of DTBN will be useful for the modification of DTBN towards developing novel anti-MRSA and anti-VRE drug.
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Affiliation(s)
- Shinya Okamura
- Department of Microbiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
| | - Eri Nishiyama
- Department of Microbiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
| | - Tomohiro Yamazaki
- Department of Microbiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
| | - Nao Otsuka
- Department of Microbiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
| | - Shoko Taniguchi
- Botanical Garden, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
| | - Wakano Ogawa
- Department of Microbiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
| | - Tsutomu Hatano
- Natural Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
| | - Tomofusa Tsuchiya
- Department of Microbiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
| | - Teruo Kuroda
- Department of Microbiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
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189
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Diagnosing oxidative stress in bacteria: not as easy as you might think. Curr Opin Microbiol 2015; 24:124-31. [PMID: 25666086 DOI: 10.1016/j.mib.2015.01.004] [Citation(s) in RCA: 159] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 12/31/2014] [Accepted: 01/08/2015] [Indexed: 12/31/2022]
Abstract
Microorganisms are vulnerable to elevated levels of intracellular reactive oxygen species (ROS). This situation has led to proposals that many natural stresses might be toxic specifically because they accelerate endogenous ROS formation. Such a mechanism has been convincingly demonstrated for redox-cycling compounds. However, the evidence is much weaker for most other stressors. The hypothesis that clinical antibiotics generate lethal ROS stress has attracted much attention, and the author discusses some aspects of evidence that support or oppose this idea. Importantly, even if all cellular electron flow were somehow diverted to ROS formation, the resultant doses of H2O2 and O2(-) would more likely be bacteriostatic than bacteriocidal unless key defense mechanisms were simultaneously blocked.
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190
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Generation of reactive oxygen species by lethal attacks from competing microbes. Proc Natl Acad Sci U S A 2015; 112:2181-6. [PMID: 25646446 DOI: 10.1073/pnas.1425007112] [Citation(s) in RCA: 112] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Whether antibiotics induce the production of reactive oxygen species (ROS) that contribute to cell death is an important yet controversial topic. Here, we report that lethal attacks from bacterial and viral species also result in ROS production in target cells. Using soxS as an ROS reporter, we found soxS was highly induced in Escherichia coli exposed to various forms of attacks mediated by the type VI secretion system (T6SS), P1vir phage, and polymyxin B. Using a fluorescence ROS probe, we found enhanced ROS levels correlate with induced soxS in E. coli expressing a toxic T6SS antibacterial effector and in E. coli treated with P1vir phage or polymyxin B. We conclude that both contact-dependent and contact-independent interactions with aggressive competing bacterial species and viruses can induce production of ROS in E. coli target cells.
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191
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Beneš D, Sosík P, Rodríguez-Patón A. An autonomous in vivo dual selection protocol for boolean genetic circuits. ARTIFICIAL LIFE 2015; 21:247-260. [PMID: 25622012 DOI: 10.1162/artl_a_00160] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Success in synthetic biology depends on the efficient construction of robust genetic circuitry. However, even the direct engineering of the simplest genetic elements (switches, logic gates) is a challenge and involves intense lab work. As the complexity of biological circuits grows, it becomes more complicated and less fruitful to rely on the rational design paradigm, because it demands many time-consuming trial-and-error cycles. One of the reasons is the context-dependent behavior of small assembly parts (like BioBricks), which in a complex environment often interact in an unpredictable way. Therefore, the idea of evolutionary engineering (artificial directed in vivo evolution) based on screening and selection of randomized combinatorial genetic circuit libraries became popular. In this article we build on the so-called dual selection technique. We propose a plasmid-based framework using toxin-antitoxin pairs together with the relaxase conjugative protein, enabling an efficient autonomous in vivo evolutionary selection of simple Boolean circuits in bacteria (E. coli was chosen for demonstration). Unlike previously reported protocols, both on and off selection steps can run simultaneously in various cells in the same environment without human intervention; and good circuits not only survive the selection process but are also horizontally transferred by conjugation to the neighbor cells to accelerate the convergence rate of the selection process. Our directed evolution strategy combines a new dual selection method with fluorescence-based screening to increase the robustness of the technique against mutations. As there are more orthogonal toxin-antitoxin pairs in E. coli, the approach is likely to be scalable to more complex functions. In silico experiments based on empirical data confirm the high search and selection capability of the protocol.
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Affiliation(s)
| | - Petr Sosík
- Silesian University in OpavaUniversidad Politécnica de Madrid
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192
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Antibacterial mechanisms of polymyxin and bacterial resistance. BIOMED RESEARCH INTERNATIONAL 2015; 2015:679109. [PMID: 25664322 PMCID: PMC4312571 DOI: 10.1155/2015/679109] [Citation(s) in RCA: 138] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 11/10/2014] [Indexed: 11/18/2022]
Abstract
Multidrug resistance in pathogens is an increasingly significant threat for human health. Indeed, some strains are resistant to almost all currently available antibiotics, leaving very limited choices for antimicrobial clinical therapy. In many such cases, polymyxins are the last option available, although their use increases the risk of developing resistant strains. This review mainly aims to discuss advances in unraveling the mechanisms of antibacterial activity of polymyxins and bacterial tolerance together with the description of polymyxin structure, synthesis, and structural modification. These are expected to help researchers not only develop a series of new polymyxin derivatives necessary for future medical care, but also optimize the clinical use of polymyxins with minimal resistance development.
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193
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Gurunathan S, Jeong JK, Han JW, Zhang XF, Park JH, Kim JH. Multidimensional effects of biologically synthesized silver nanoparticles in Helicobacter pylori, Helicobacter felis, and human lung (L132) and lung carcinoma A549 cells. NANOSCALE RESEARCH LETTERS 2015; 10:35. [PMID: 25852332 PMCID: PMC4384991 DOI: 10.1186/s11671-015-0747-0] [Citation(s) in RCA: 130] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 01/10/2015] [Indexed: 05/18/2023]
Abstract
Silver nanoparticles (AgNPs) are prominent group of nanomaterials and are recognized for their diverse applications in various health sectors. This study aimed to synthesize the AgNPs using the leaf extract of Artemisia princeps as a bio-reductant. Furthermore, we evaluated the multidimensional effect of the biologically synthesized AgNPs in Helicobacter pylori, Helicobacter felis, and human lung (L132) and lung carcinoma (A549) cells. UV-visible (UV-vis) spectroscopy confirmed the synthesis of AgNPs. X-ray diffraction (XRD) indicated that the AgNPs are specifically indexed to a crystal structure. The results from Fourier transform infrared spectroscopy (FTIR) indicate that biomolecules are involved in the synthesis and stabilization of AgNPs. Dynamic light scattering (DLS) studies showed the average size distribution of the particle between 10 and 40 nm, and transmission electron microscopy (TEM) confirmed that the AgNPs were significantly well separated and spherical with an average size of 20 nm. AgNPs caused dose-dependent decrease in cell viability and biofilm formation and increase in reactive oxygen species (ROS) generation and DNA fragmentation in H. pylori and H. felis. Furthermore, AgNPs induced mitochondrial-mediated apoptosis in A549 cells; conversely, AgNPs had no significant effects on L132 cells. The results from this study suggest that AgNPs could cause cell-specific apoptosis in mammalian cells. Our findings demonstrate that this environmentally friendly method for the synthesis of AgNPs and that the prepared AgNPs have multidimensional effects such as anti-bacterial and anti-biofilm activity against H. pylori and H. felis and also cytotoxic effects against human cancer cells. This report describes comprehensively the effects of AgNPs on bacteria and mammalian cells. We believe that biologically synthesized AgNPs will open a new avenue towards various biotechnological and biomedical applications in the near future.
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Affiliation(s)
- Sangiliyandi Gurunathan
- />Department of Animal Biotechnology, Konkuk University, 1 Hwayang-Dong, Gwanjgin-gu, 143-701 Seoul South Korea
- />GS Institute of Bio and Nanotechnology, Coimbatore, Tamilnadu India
| | - Jae-Kyo Jeong
- />Department of Animal Biotechnology, Konkuk University, 1 Hwayang-Dong, Gwanjgin-gu, 143-701 Seoul South Korea
| | - Jae Woong Han
- />Department of Animal Biotechnology, Konkuk University, 1 Hwayang-Dong, Gwanjgin-gu, 143-701 Seoul South Korea
| | - Xi-Feng Zhang
- />Department of Animal Biotechnology, Konkuk University, 1 Hwayang-Dong, Gwanjgin-gu, 143-701 Seoul South Korea
| | - Jung Hyun Park
- />Department of Animal Biotechnology, Konkuk University, 1 Hwayang-Dong, Gwanjgin-gu, 143-701 Seoul South Korea
| | - Jin-Hoi Kim
- />Department of Animal Biotechnology, Konkuk University, 1 Hwayang-Dong, Gwanjgin-gu, 143-701 Seoul South Korea
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194
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Kotova VY, Mironov AS, Zavilgelsky GB. Role of reactive oxygen species in the bactericidal action of quinolones as inhibitors of DNA gyrase. Mol Biol 2014. [DOI: 10.1134/s0026893314060107] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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195
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Citorik RJ, Mimee M, Lu TK. Sequence-specific antimicrobials using efficiently delivered RNA-guided nucleases. Nat Biotechnol 2014; 32:1141-5. [PMID: 25240928 PMCID: PMC4237163 DOI: 10.1038/nbt.3011] [Citation(s) in RCA: 459] [Impact Index Per Article: 45.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Accepted: 08/07/2014] [Indexed: 02/06/2023]
Abstract
Current antibiotics tend to be broad spectrum, leading to indiscriminate killing of commensal bacteria and accelerated evolution of drug resistance. Here, we use CRISPR-Cas technology to create antimicrobials whose spectrum of activity is chosen by design. RNA-guided nucleases (RGNs) targeting specific DNA sequences are delivered efficiently to microbial populations using bacteriophage or bacteria carrying plasmids transmissible by conjugation. The DNA targets of RGNs can be undesirable genes or polymorphisms, including antibiotic resistance and virulence determinants in carbapenem-resistant Enterobacteriaceae and enterohemorrhagic Escherichia coli. Delivery of RGNs significantly improves survival in a Galleria mellonella infection model. We also show that RGNs enable modulation of complex bacterial populations by selective knockdown of targeted strains based on genetic signatures. RGNs constitute a class of highly discriminatory, customizable antimicrobials that enact selective pressure at the DNA level to reduce the prevalence of undesired genes, minimize off-target effects and enable programmable remodeling of microbiota.
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Affiliation(s)
- Robert J Citorik
- 1] MIT Microbiology Program, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA. [2] MIT Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Mark Mimee
- 1] MIT Microbiology Program, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA. [2] MIT Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Timothy K Lu
- 1] MIT Microbiology Program, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA. [2] MIT Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA. [3] Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA. [4] Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA. [5] Harvard Biophysics Program, Harvard University, Boston, Massachusetts, USA. [6] Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
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196
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Méhi O, Bogos B, Csörgő B, Pál F, Nyerges A, Papp B, Pál C. Perturbation of iron homeostasis promotes the evolution of antibiotic resistance. Mol Biol Evol 2014; 31:2793-804. [PMID: 25063442 PMCID: PMC4166929 DOI: 10.1093/molbev/msu223] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Evolution of antibiotic resistance in microbes is frequently achieved by acquisition of spontaneous mutations during antimicrobial therapy. Here, we demonstrate that inactivation of a central transcriptional regulator of iron homeostasis (Fur) facilitates laboratory evolution of ciprofloxacin resistance in Escherichia coli. To decipher the underlying molecular mechanisms, we first performed a global transcriptome analysis and demonstrated that the set of genes regulated by Fur changes substantially in response to antibiotic treatment. We hypothesized that the impact of Fur on evolvability under antibiotic pressure is due to the elevated intracellular concentration of free iron and the consequent enhancement of oxidative damage-induced mutagenesis. In agreement with expectations, overexpression of iron storage proteins, inhibition of iron transport, or anaerobic conditions drastically suppressed the evolution of resistance, whereas inhibition of the SOS response-mediated mutagenesis had only a minor effect. Finally, we provide evidence that a cell permeable iron chelator inhibits the evolution of resistance. In sum, our work revealed the central role of iron metabolism in the de novo evolution of antibiotic resistance, a pattern that could influence the development of novel antimicrobial strategies.
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Affiliation(s)
- Orsolya Méhi
- Synthetic and Systems Biology Unit, Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, Hungary
| | - Balázs Bogos
- Synthetic and Systems Biology Unit, Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, Hungary
| | - Bálint Csörgő
- Synthetic and Systems Biology Unit, Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, Hungary
| | - Ferenc Pál
- Synthetic and Systems Biology Unit, Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, Hungary
| | - Akos Nyerges
- Synthetic and Systems Biology Unit, Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, Hungary
| | - Balázs Papp
- Synthetic and Systems Biology Unit, Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, Hungary
| | - Csaba Pál
- Synthetic and Systems Biology Unit, Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, Hungary
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197
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Dwyer DJ, Collins JJ, Walker GC. Unraveling the physiological complexities of antibiotic lethality. Annu Rev Pharmacol Toxicol 2014; 55:313-32. [PMID: 25251995 DOI: 10.1146/annurev-pharmtox-010814-124712] [Citation(s) in RCA: 188] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We face an impending crisis in our ability to treat infectious disease brought about by the emergence of antibiotic-resistant pathogens and a decline in the development of new antibiotics. Urgent action is needed. This review focuses on a less well-understood aspect of antibiotic action: the complex metabolic events that occur subsequent to the interaction of antibiotics with their molecular targets and play roles in antibiotic lethality. Independent lines of evidence from studies of the action of bactericidal antibiotics on diverse bacteria collectively suggest that the initial interactions of drugs with their targets cannot fully account for the antibiotic lethality and that these interactions elicit the production of reactive oxidants including reactive oxygen species that contribute to bacterial cell death. Recent challenges to this concept are considered in the context of the broader literature of this emerging area of research. Possible ways that this new knowledge might be exploited to improve antibiotic therapy are also considered.
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Affiliation(s)
- Daniel J Dwyer
- Department of Cell Biology and Molecular Genetics, Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742;
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198
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Li O, Liu A, Lu C, Zheng DQ, Qian CD, Wang PM, Jiang XH, Wu XC. Increasing viscosity and yields of bacterial exopolysaccharides by repeatedly exposing strains to ampicillin. Carbohydr Polym 2014; 110:203-8. [DOI: 10.1016/j.carbpol.2014.03.069] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2013] [Revised: 03/03/2014] [Accepted: 03/20/2014] [Indexed: 10/25/2022]
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199
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Wang Z, Wu X, Peng J, Hu Y, Fang B, Huang S. Artificially constructed quorum-sensing circuits are used for subtle control of bacterial population density. PLoS One 2014; 9:e104578. [PMID: 25119347 PMCID: PMC4132116 DOI: 10.1371/journal.pone.0104578] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 07/15/2014] [Indexed: 01/31/2023] Open
Abstract
Vibrio fischeri is a typical quorum-sensing bacterium for which lux box, luxR, and luxI have been identified as the key elements involved in quorum sensing. To decode the quorum-sensing mechanism, an artificially constructed cell–cell communication system has been built. In brief, the system expresses several programmed cell-death BioBricks and quorum-sensing genes driven by the promoters lux pR and PlacO-1 in Escherichia coli cells. Their transformation and expression was confirmed by gel electrophoresis and sequencing. To evaluate its performance, viable cell numbers at various time periods were investigated. Our results showed that bacteria expressing killer proteins corresponding to ribosome binding site efficiency of 0.07, 0.3, 0.6, or 1.0 successfully sensed each other in a population-dependent manner and communicated with each other to subtly control their population density. This was also validated using a proposed simple mathematical model.
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Affiliation(s)
- Zhaoshou Wang
- Institute of Biochemical Engineering, Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China
- The Key Lab for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen, China
| | - Xin Wu
- Institute of Biochemical Engineering, Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China
- The Key Lab for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen, China
| | - Jianghai Peng
- Institute of Biochemical Engineering, Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China
| | - Yidan Hu
- Institute of Biochemical Engineering, Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China
- The Key Lab for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen, China
| | - Baishan Fang
- Institute of Biochemical Engineering, Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China
- The Key Lab for Chemical Biology of Fujian Province, Xiamen University, Xiamen, China
- The Key Lab for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen, China
- * E-mail:
| | - Shiyang Huang
- Institute of Biochemical Engineering, Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China
- The Key Lab for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen, China
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200
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Enhanced killing of antibiotic-resistant bacteria enabled by massively parallel combinatorial genetics. Proc Natl Acad Sci U S A 2014; 111:12462-7. [PMID: 25114216 DOI: 10.1073/pnas.1400093111] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
New therapeutic strategies are needed to treat infections caused by drug-resistant bacteria, which constitute a major growing threat to human health. Here, we use a high-throughput technology to identify combinatorial genetic perturbations that can enhance the killing of drug-resistant bacteria with antibiotic treatment. This strategy, Combinatorial Genetics En Masse (CombiGEM), enables the rapid generation of high-order barcoded combinations of genetic elements for high-throughput multiplexed characterization based on next-generation sequencing. We created ∼ 34,000 pairwise combinations of Escherichia coli transcription factor (TF) overexpression constructs. Using Illumina sequencing, we identified diverse perturbations in antibiotic-resistance phenotypes against carbapenem-resistant Enterobacteriaceae. Specifically, we found multiple TF combinations that potentiated antibiotic killing by up to 10(6)-fold and delivered these combinations via phagemids to increase the killing of highly drug-resistant E. coli harboring New Delhi metallo-beta-lactamase-1. Moreover, we constructed libraries of three-wise combinations of transcription factors with >4 million unique members and demonstrated that these could be tracked via next-generation sequencing. We envision that CombiGEM could be extended to other model organisms, disease models, and phenotypes, where it could accelerate massively parallel combinatorial genetics studies for a broad range of biomedical and biotechnology applications, including the treatment of antibiotic-resistant infections.
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