Abstract
Aim:
To examine whether the novel cyclic lipopeptide antibiotic daptomycin could be used to treat anthrax and to study the mechanisms underlying its bactericidal action against Bacillus anthracis.
Methods:
Spore-forming B anthracis AP422 was tested. MIC values of antibiotics were determined. Cell membrane potential was measured using flow cytometric assays with membrane potential-sensitive fluorescent dyes. Cell membrane integrity was detected using To-Pro-3 iodide staining and transmission electron microscopy. K+ efflux and Na+ influx were measured using the fluorescent probes PBFI and SBFI-AM, respectively.
Results:
Daptomycin exhibited rapid bactericidal activity against vegetative B anthracis with a MIC value of 0.78 μg/mL, which was comparable to those of ciprofloxacin and penicillin G. Furthermore, daptomycin prevented the germinated spores from growing into vegetative bacteria. Daptomycin concentration-dependently dissipated the membrane potential of B anthracis and caused K+ efflux and Na+ influx without disrupting membrane integrity. In contrast, both ciprofloxacin and penicillin G did not change the membrane potential of vegetative bacteria or spores. Penicillin G disrupted membrane integrity of B anthracis, whereas ciprofloxacin had no such effect.
Conclusion:
Daptomycin exerts rapid bactericidal action against B anthracis via reducing membrane potential without disrupting membrane integrity. This antibiotic can be used as an alternate therapy for B anthracis infections.
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References
Dixon TC, Meselson M, Guillemin J, Hanna PC . Anthrax. N Engl J Med 1999; 341: 815–26.
Jernigan JA, Stephens DS, Ashford DA, Omenaca C, Topiel MS, Galbraith M, et al. Bioterrorism-related inhalational anthrax: the first 10 cases reported in the United States. Emerg Infect Dis 2001; 7: 933–44.
Inglesby TV, O'Toole T, Henderson DA, Bartlett JG, Ascher MS, Eitzen E, et al. Anthrax as a biological weapon, 2002: updated recommendations for management. JAMA 2002; 287: 2236–52.
Centers for Disease Control and Prevention (CDC). Investigation of bioterrorism-related anthrax and interim guidelines for exposure management and antimicrobial therapy. MMWR Morb Mortal Wkly Rep 2001; 50: 909–19.
Bradaric N, Punda-Polic V . Cutaneous anthrax due to penicillin-resistant Bacillus anthracis transmitted by an insect bite. Lancet 1992; 340: 306–7.
Coker PR, Smith KL, Hugh-Jones ME . Antimicrobial susceptibilities of diverse Bacillus anthracis isolates. Antimicrob Agents Chemother 2002; 46: 3843–5.
Chen Y, Tenover FC, Koehler TM . β-Lactamase gene expression in a penicillin-resistant Bacillus anthracis strain. Antimicrob Agents Chemother 2004; 48: 4873–7.
Brook I, Elliott TB, Pryor HI 2nd, Sautter TE, Gnade BT, Thakar JH, et al. In vitro resistance of Bacillus anthracis Sterne to doxycycline, macrolides and quinolones. Int J Antimicrob Agents 2001; 18: 559–62.
Athamna A, Athamna M, Abu-Rashed N, Medlej B, Bast DJ, Rubinstein E . Selection of Bacillus anthracis isolates resistant to antibiotics. J Antimicrob Chemother 2004; 54: 424–8.
Price LB, Volger A, Pearson T, Busch JD, Schupp JM, Keim P . In vitro selection and characterization of Bacillus anthracis mutants with high-level resistance to ciprofloxacin. Antimicrob Agents Chemother 2003; 47: 2362–5.
Choe CH, Bouhaouala SS, Brook I, Elliot TB, Knudson GB . In vitro development of resistance to ofloxacin and doxycycline in Bacillus anthracis Sterne. Antimicrob Agents Chemother 2000; 44: 1766.
Tally FP, Zeckel M, Wasilewski MM, Carini C, Berman CL, Drusano GL, et al. Daptomycin: a novel agent for gram-positive infections. Expert Opin Investig Drugs 1999; 8: 1223–38.
Silverman JA, Perlmutter NG, Shapiro HM . Correlation of daptomycin bactericidal activity and membrane depolarization in Staphylococcus aureus. Antimicrob Agents Chemother 2003; 47: 2538–44.
Heine HS, Bassett J, Miller L, Purcell BK, Byrne WR . Efficacy of Daptomycin against Bacillus anthracis in a murine model of anthrax spore inhalation. Antimicrob Agents Chemother 2010; 54: 4471–3.
Clinical and Laboratory Standards Institute. Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically; approved standard–ninth edition. CLSI document M07-A 9 2012. USA.
Heine HS, Bassett J, Miller L, Hartings JM, Ivins BE, Pitt ML, et al. Determination of antibiotic efficacy against Bacillus anthracis in a mouse aerosol challenge model. Antimicrob Agents Chemother 2007; 51: 1373–9.
Wu M, Hancock RE . Interaction of the cyclic antimicrobial cationic peptide bactenecin with the outer and cytoplasmic membrane. J Biol Chem 1999; 274: 29–35.
Novo D, Perlmutter NG, Hunt RH, Shapiro HM . Accurate flow cytometric membrane potential measurement in bacteria using diethyloxacarbocyanine and a ratiometric technique. Cytometry 1999; 35: 55–63.
Marrie TJ, Costerton JW . Scanning and transmission electron microscopy of in situ bacterial colonization of intravenous and intraarterial catheters. J Clin Microbiol 1984; 19: 687–93.
Herranz C, Cintas LM, Hernandez PE, Moll GN, Driessen AJ . Enterocin P causes potassium ion efflux from Enterococcus faecium T136 cells. Antimicrob Agents Chemother 2001; 45: 901–4.
Kader MA, Lindberg S . Uptake of sodium in protoplasts of salt-sensitive and salt-tolerant cultivars of rice, Oryza sativa L. determined by the fluorescent dye SBFI. J Exp Bot 2005; 56: 3149–58.
Braga PC, Ricci D, Dal Sasso M . Daptomycin morphostructural damage in Bacillus cereus visualized by atomic force microscopy. J Chemother 2002; 14: 336–41.
Diane MC, Maria DA . In vitro activities of daptomycin, ciprofloxacin, and other antimicrobial agents against the cells and spores of clinical isolates of Bacillus species. J Clin Microbiol 2006; 44: 3814–8.
Louie A, VanScoy BD, Brown DL, Kulawy RW, Heine HS, Drusano GL . Impact of spores on the comparative efficacies of five antibiotics for treatment of Bacillus anthracis in an in vitro hollow fiber pharmacodynamic model. Antimicrob Agents Chemother 2012; 56: 1229–39.
Setlow P . Resistance of bacterial spores. In: Storz G, Hengge RA, editors. In Bacterial Stress Responses. Washington, DC, USA: ASM Press 2000; p 217–30.
Nicholson WL, Munakata N, Horneck G, Melosh HJ, Setlow P . Resistance of Bacillus endospores to extreme terrestrial and extraterrestrial environments. Microbiol Mol Biol Rev 2000; 64: 548–72.
Suzana KS, Robert EW . Mode of action of the new antibiotic for Gram-positive pathogens daptomycin: Comparison with cationic antimicrobial peptides and lipopeptides. Biochim Biophys Acta 2006; 1758: 1215–23.
Laganas V, Alder J, Silverman JA . In vitro bactericidal activities of daptomycin against Staphylococcus aureus and Enterococcus faecalis are not mediated by inhibition of lipoteichoic acid biosynthesis. Antimicrob Agents Chemother 2003; 47: 2682–4.
Gut IM, Blanke SR, Donk WA . Mechanism of inhibition of Bacillus anthracis spore outgrowth by the lantibiotic nisin. ACS Chem Biol 2011; 6: 744–52.
Acknowledgements
This work was supported by the National High Technology Research and Development Program (“863”Program) of China (2012AA022001-03D). We thank Dr Chun-Jie LIU and Dr Yan-chun WANG for the B anthracis AP422 strain and their assistance with experimental procedures. We thank Dr Xian-wen HU and Dr Yong-yi XI for helpful advice and reagents.
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Xing, Yh., Wang, W., Dai, Sq. et al. Daptomycin exerts rapid bactericidal activity against Bacillus anthracis without disrupting membrane integrity. Acta Pharmacol Sin 35, 211–218 (2014). https://doi.org/10.1038/aps.2013.159
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DOI: https://doi.org/10.1038/aps.2013.159
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