Summary: A trypanocidal agent and possible antiviral agent that is widely used in experimental cell biology and biochemistry. Ethidium has several experimentally useful properties including binding to nucleic acids, noncompetitive inhibition of nicotinic acetylcholine receptors, and fluorescence among others. It is most commonly used as the bromide.

Top Publications

  1. Lechner D, Gibbons S, Bucar F. Plant phenolic compounds as ethidium bromide efflux inhibitors in Mycobacterium smegmatis. J Antimicrob Chemother. 2008;62:345-8 pubmed publisher
    ..The study was performed to set up an ethidium bromide (EtBr) efflux assay in Mycobacterium smegmatis mc(2)155 for testing plant natural compounds as ..
  2. Kao L, Ovchinnikov D, Wolvetang E. The effect of ethidium bromide and chloramphenicol on mitochondrial biogenesis in primary human fibroblasts. Toxicol Appl Pharmacol. 2012;261:42-9 pubmed
    ..We treated primary human fibroblasts with ethidium bromide (EtBr) or chloramphenicol for six weeks to inhibit mtDNA replication or mitochondrial protein synthesis, ..
  3. Lee W, Reichold M, Edemir B, Ciarimboli G, Warth R, Koepsell H, et al. Organic cation transporters OCT1, 2, and 3 mediate high-affinity transport of the mutagenic vital dye ethidium in the kidney proximal tubule. Am J Physiol Renal Physiol. 2009;296:F1504-13 pubmed publisher
    The positively charged fluorescent dyes ethidium (Et(+)) and propidium (Pr(2+)) are widely used as DNA and necrosis markers. Et(+) is cytotoxic and mutagenic...
  4. Hauschild K, Stover J, Boger D, Ansari A. CSI-FID: high throughput label-free detection of DNA binding molecules. Bioorg Med Chem Lett. 2009;19:3779-82 pubmed publisher
    ..Analysis of the DNA binding properties of protein- and small molecule-based libraries with CSI-FID will advance the development of genome-anchored molecules for therapeutic purposes. ..
  5. Lee W, Wolff N, Thevenod F. Organic cation transporters: physiology, toxicology and special focus on ethidium as a novel substrate. Curr Drug Metab. 2009;10:617-31 pubmed
    ..This review highlights a novel role of human and rodent OCTs as carriers of the toxic fluorescent dye ethidium, as opposed to the less harmful related phenanthridine compound propidium, which is not transported...
  6. Peters K, Sharbeen G, Theis T, Skurray R, Brown M. Biochemical characterization of the multidrug regulator QacR distinguishes residues that are crucial to multidrug binding and induction of qacA transcription. Biochemistry. 2009;48:9794-800 pubmed publisher
    ..In response to binding cationic lipophilic compounds, including ethidium and rhodamine 6G, QacR dissociates from the qacA operator alleviating repression...
  7. Jin J, Zhang J, Guo N, Feng H, Li L, Liang J, et al. The plant alkaloid piperine as a potential inhibitor of ethidium bromide efflux in Mycobacterium smegmatis. J Med Microbiol. 2011;60:223-9 pubmed publisher
    ..In this study, a modulation assay showed that piperine could decrease the MIC of ethidium bromide (EtBr) twofold at 32 ?g ml(-1) and fourfold at 64 ?g ml(-1) against Mycobacterium ..
  8. Roy Chowdhury A, Bakshi R, Wang J, Yildirir G, Liu B, Pappas Brown V, et al. The killing of African trypanosomes by ethidium bromide. PLoS Pathog. 2010;6:e1001226 pubmed publisher
    Introduced in the 1950s, ethidium bromide (EB) is still used as an anti-trypanosomal drug for African cattle although its mechanism of killing has been unclear and controversial...
  9. Rodrigues L, Ramos J, Couto I, Amaral L, Viveiros M. Ethidium bromide transport across Mycobacterium smegmatis cell-wall: correlation with antibiotic resistance. BMC Microbiol. 2011;11:35 pubmed publisher
    ..smegmatis) and its repressor LfrR for their ability to transport ethidium bromide (EtBr) on a real-time basis...

More Information


  1. Martins M, Viveiros M, Couto I, Costa S, Pacheco T, Fanning S, et al. Identification of efflux pump-mediated multidrug-resistant bacteria by the ethidium bromide-agar cartwheel method. In Vivo. 2011;25:171-8 pubmed
    ..Conventional evaluation of efflux activity using efflux pump substrates, such as ethidium bromide, requires specialised instrumentation...
  2. Shilling R, Federici L, Walas F, Venter H, Velamakanni S, Woebking B, et al. A critical role of a carboxylate in proton conduction by the ATP-binding cassette multidrug transporter LmrA. FASEB J. 2005;19:1698-700 pubmed
    ..In a previous study, LmrA was shown to mediate ethidium efflux by an ATP-dependent proton-ethidium symport reaction in which the carboxylate E314 is critical...
  3. Amaral L, Cerca P, Spengler G, Machado L, Martins A, Couto I, et al. Ethidium bromide efflux by Salmonella: modulation by metabolic energy, pH, ions and phenothiazines. Int J Antimicrob Agents. 2011;38:140-5 pubmed publisher
    ..its energy for the extrusion of noxious agents from the proton-motive force, was studied with the aid of an ethidium bromide (EtBr) semi-automated method under conditions that define the role of metabolic energy, ions and pH in ..
  4. Czechowska K, van der Meer J. Reversible and irreversible pollutant-induced bacterial cellular stress effects measured by ethidium bromide uptake and efflux. Environ Sci Technol. 2012;46:1201-8 pubmed publisher
    ..As a proxy for physiological disturbance we measured changes in geometric mean ethidium bromide (EB) fluorescence intensities in subpopulations of live and dividing cells exposed or not exposed to ..
  5. Zhang G, Hu X, Fu P. Spectroscopic studies on the interaction between carbaryl and calf thymus DNA with the use of ethidium bromide as a fluorescence probe. J Photochem Photobiol B. 2012;108:53-61 pubmed publisher
    ..4) using ethidium bromide (EB) dye as a probe by UV-vis absorption, fluorescence and circular dichroism (CD) spectroscopy, as well ..
  6. Byczkowska A, Kunikowska A, Kazmierczak A. Determination of ACC-induced cell-programmed death in roots of Vicia faba ssp. minor seedlings by acridine orange and ethidium bromide staining. Protoplasma. 2013;250:121-8 pubmed publisher
    Fluorescence staining with acridine orange (AO) and ethidium bromide (EB) showed that nuclei of cortex root cells of 1-aminocyclopropane-1-carboxylic acid (ACC)-treated Vicia faba ssp. minor seedlings differed in color...
  7. Farrow M, Rubin E. Function of a mycobacterial major facilitator superfamily pump requires a membrane-associated lipoprotein. J Bacteriol. 2008;190:1783-91 pubmed publisher
    ..A deletion of the homologous operon in Mycobacterium smegmatis is more susceptible to ethidium bromide, and drug resistance is restored by the intact operon from M. tuberculosis...
  8. Rodrigues L, Wagner D, Viveiros M, Sampaio D, Couto I, Vavra M, et al. Thioridazine and chlorpromazine inhibition of ethidium bromide efflux in Mycobacterium avium and Mycobacterium smegmatis. J Antimicrob Chemother. 2008;61:1076-82 pubmed publisher
    ..We have characterized the efflux pump activity of M. avium wild-type strain through an automated fluorometric method and correlated it with intrinsic resistance to antibiotics...
  9. Tippett E, Fernandes L, Rogerson S, Jaworowski A. A novel flow cytometric phagocytosis assay of malaria-infected erythrocytes. J Immunol Methods. 2007;325:42-50 pubmed
    ..malaria we have established several novel malaria-specific flow cytometric phagocytosis assays based on ethidium bromide staining of DNA present in blood stage trophozoites...
  10. Bapna A, Federici L, Venter H, Velamakanni S, Luisi B, Fan T, et al. Two proton translocation pathways in a secondary active multidrug transporter. J Mol Microbiol Biotechnol. 2007;12:197-209 pubmed
    ..Previous work has indicated that ethidium, a monovalent cationic substrate, is exported by LmrP by electrogenic antiport with two (or more) protons...
  11. Edwards J, Diamantakos E, Peuler J, Lamar P, Prozialeck W. A novel method for the evaluation of proximal tubule epithelial cellular necrosis in the intact rat kidney using ethidium homodimer. BMC Physiol. 2007;7:1 pubmed
    b>Ethidium homodimer is a cell-membrane impermeant nuclear fluorochrome that has been widely used to identify necrotic cells in culture...
  12. Rapp M, Seppälä S, Granseth E, von Heijne G. Emulating membrane protein evolution by rational design. Science. 2007;315:1282-4 pubmed
    ..This simple evolutionary pathway can explain the frequent occurrence of membrane proteins with an internal pseudo-two-fold symmetry axis in the plane of the membrane. ..
  13. Islam M, Sinha R, Kumar G. RNA binding small molecules: studies on t-RNA binding by cytotoxic plant alkaloids berberine, palmatine and the comparison to ethidium. Biophys Chem. 2007;125:508-20 pubmed
    ..various biophysical techniques and the data was compared with the binding of the classical DNA intercalator, ethidium. The results of optical thermal melting, differential scanning calorimetry and circular dichroism characterized ..
  14. Ribble D, Goldstein N, Norris D, Shellman Y. A simple technique for quantifying apoptosis in 96-well plates. BMC Biotechnol. 2005;5:12 pubmed
    ..that quantify apoptosis in vitro and to take advantage of the 96-well plate format, we present here a modified ethidium bromide and acridine orange (EB/AO) staining assay, which may be performed entirely in a 96-well plate...
  15. Colangeli R, Helb D, Sridharan S, Sun J, Varma Basil M, Hazbón M, et al. The Mycobacterium tuberculosis iniA gene is essential for activity of an efflux pump that confers drug tolerance to both isoniazid and ethambutol. Mol Microbiol. 2005;55:1829-40 pubmed
    ..Additional studies showed that overexpression of M. tuberculosis iniA in BCG conferred resistance to ethidium bromide, and the deletion of iniA in M...
  16. Bailly C, Arafa R, Tanious F, Laine W, Tardy C, Lansiaux A, et al. Molecular determinants for DNA minor groove recognition: design of a bis-guanidinium derivative of ethidium that is highly selective for AT-rich DNA sequences. Biochemistry. 2005;44:1941-52 pubmed
    The phenanthridinium dye ethidium bromide is a prototypical DNA intercalating agent. For decades, this anti-trypanosomal agent has been known to intercalate into nucleic acids, with little preference for particular sequences...
  17. Maniura Weber K, Goffart S, Garstka H, Montoya J, Wiesner R. Transient overexpression of mitochondrial transcription factor A (TFAM) is sufficient to stimulate mitochondrial DNA transcription, but not sufficient to increase mtDNA copy number in cultured cells. Nucleic Acids Res. 2004;32:6015-27 pubmed
    ..Stimulation of transcription was more evident when TFAM was transiently overexpressed in cells pre-treated with ethidium bromide (EBr) having lowered mtDNA, TFAM and mitochondrial transcript levels...