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Volume 146, Issue 12

The microaerophilic flagellate : oxygen and its reaction products collapse membrane potential and cause cytotoxicity Free

Abstract

Trophozoites of the microaerophilic flagellate parasitic protozoon have only a limited capacity to detoxify O. Thus, when exposed to controlled concentrations of dissolved O >8 μM, they gradually lose their ability to scavenge O. In a washed cell suspension stirred under 10% air in N (equivalent to 25 μM O), inactivation of the O-consuming system was complete after 35 h; during this period accumulation of HO (3 μmol per 10 organisms) and oxidation of cellular thiols to 16% of their initial level occurred. Under 20% air (50 μM O), respiratory inactivation was complete after 15 h, and under air (258 μM O), after 50 min. Loss of O-consuming capacity was accompanied by loss of motility. Use of the fluorogen 2,7-dichlorodihydrofluorescein acetate indicated that intracellular HO is produced at extranuclear sites. Flow cytometric estimation of the plasma membrane electrochemical potentials using bis(1,3-dibutylbarbituric acid) trimethine oxonol, DiBAC(3), showed that values declined from −134 mV to −20 mV after 45 h aeration. Incubation of organisms with 60 μM HO for 10 min gave partial collapse of plasma membrane potential and complete loss of O uptake capacity; motility and viability as assessed by DiBAC(3) exclusion were completely lost after 1 h. Inactivation of the O-consuming system and loss of viability were also observed on exposure to singlet oxygen photochemically generated from rose bengal or toluidine blue.

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Keyword(s): CCCP, carbonyl cyanide m-chlorophenylhydrazone , DCCD, N,N’-dicyclohexylcarbodiimide , DiBAC4(3), bis(1,3-dibutylbarbituric acid) trimethine oxonol , hydrogen peroxide , oxidative stress and reactive oxygen species
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2000-12-01
2024-04-24
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References

  1. Aruoma O. I., Halliwell B., Gajewski E., Dizdaroglu M. 1989; Damage to the bases in DNA induced by hydrogen peroxide and ferric ion chelates. J Biol Chem 264:20509–20512
     [Google Scholar]
  2. Atkinson H. J. 1980; Respiration. In Nematodes as Biological Models pp. 101–138Edited by Zuckerman B. H. . London: Academic Press;
     [Google Scholar]
  3. Brown D. M., Upcroft J. A., Upcroft P. 1995; Free radical detoxification in Giardia duodenalis. Mol Biochem Parasitol 72:47–56 [CrossRef]
     [Google Scholar]
  4. Craun G. F. 1990; Waterborne giardiasis. In Giardiasis. Human Parasitic Disease pp. 267–290Edited by Meyer E. A. Amsterdam: Elsevier;
     [Google Scholar]
  5. Edwards M. R., Gilroy F. V., Jiminez M. B., O’Sullivan W. J. 1989; Alanine is a major end product of metabolism by Giardia lamblia: a proton nuclear magnetic resonance study. Mol Biochem Parasitol 37:19–26 [CrossRef]
     [Google Scholar]
  6. Ellis J. E., Williams R., Cole D., Cammack R., Lloyd D. 1993; Electron transport components of the parasitic protozoon Giardia lamblia. FEBS Lett 325:196–200 [CrossRef]
     [Google Scholar]
  7. Ellman G. L. 1959; Method for the modification and quantitative detection of thiol groups. Arch Biochem Biophys 82:70 [CrossRef]
     [Google Scholar]
  8. Emri M., Balkay L., Krasznai Z., Tron L., Martin T. 1998; Wide applicability of a flow cytometric assay to measure absolute membrane potentials on a millivolt scale. Eur Biophys J 28:78–83 [CrossRef]
     [Google Scholar]
  9. Halliwell B. 1978; Superoxide-dependent formation of hydroxyl radicals in the presence of iron chelates. FEBS Lett 92:321–326 [CrossRef]
     [Google Scholar]
  10. Halliwell B., Gutteridge J. M. C. 1989 Free Radicals in Biology and Medicine Oxford: Oxford University Press;
     [Google Scholar]
  11. Keister D. B. 1983; Axenic culture of Giardia lamblia in TYI-S-33 medium supplemented with bile. Trans R Soc Trop Med Hyg 77:487–488 [CrossRef]
     [Google Scholar]
  12. Krasznai Z., Marian T., Balkay L., Emri M., Tron L. 1995; Flow cytometric determination of absolute membrane potential of cells. J Photochem Photobiol B Biol 28:93–99 [CrossRef]
     [Google Scholar]
  13. Krinsky N. I. 1979; Biological roles of singlet oxygen. In Singlet Oxygen pp. 597–641Edited by Wasserman H. H., Murray R. W. London: Academic Press;
     [Google Scholar]
  14. Lamberts J. J. M., Neckers D. C. 1985; Rose Bengal derivatives as singlet oxygen sensitizers. Tetrahedron 41:2183–2190 [CrossRef]
     [Google Scholar]
  15. Lloyd D., Hayes A. J. 1995; Vigour, vitality and viability of microorganisms. FEMS Microbiol Lett 133:1–7 [CrossRef]
     [Google Scholar]
  16. Lloyd D., Edwards S. W., Kristensen B., Degn H. 1979; The effect of inhibitors on the oxygen kinetics of terminal oxidases of Acanthamoeba castellanii. Biochem J 182:11–15
     [Google Scholar]
  17. Lundsgaard J., Degn H. 1973; A digital gas mixer. IEEE Trans Biomed Eng 20:384–387
     [Google Scholar]
  18. Meyer E. A. 1976; Giardia lamblia: isolation and axenic cultivation. Exp Parasitol 39:301–310
     [Google Scholar]
  19. Ortega Y. R., Adam R. D. 1997; Giardia: overview and update. Clin Infect Dis 25:545–550 [CrossRef]
     [Google Scholar]
  20. Paget T., Jarroll E., Manning P., Lindmark D., Lloyd D. 1989; Respiration in the cysts and trophozoites of Giardia muris. J Gen Microbiol 13:145–154
     [Google Scholar]
  21. Paget T., Raynor M. H., Shipp D. W. E., Lloyd D. 1990; Giardia lamblia produces alanine anaerobically but not in the presence of oxygen. Mol Biochem Parasitol 42:63–68 [CrossRef]
     [Google Scholar]
  22. Paget T., Kelly M., Jarroll E., Lindmark D., Lloyd D. 1993; The effects of oxygen on fermentation in Giardia lamblia. Mol Biochem Parasitol 57:65–72 [CrossRef]
     [Google Scholar]
  23. Park J. H., Schofield P. J., Edwards M. R. 1995; The role of alanine in the acute response of Giardia intestinalis to hypo-osmotic shock. Microbiology 141:2455–2462 [CrossRef]
     [Google Scholar]
  24. Shukry S., Zaki A. M., Dupont H. L., Shoukry I., El Tagi M., Hamed S. 1986; Detection of enteropathogens in fatal and potentially fatal diarrhea in Cairo, Egypt. Clin Microbiol 24:959–962
     [Google Scholar]
  25. Smith H. V., Robertson L. J., Campbell A. T., Girdwood R. W. A. 1995; Giardia and giardiasis: what’s in a name. Microbiol Eur 3:22–29
     [Google Scholar]
  26. Smith N. C., Bryant C., Boreham D. F. L. 1988; Possible roles for pyruvate–ferredoxin oxidoreductase and thiol-dependent peroxidase and reductase activities in resistance to nitroheterocyclic drugs in Giardia intestinalis. Int J Parasitol 18:991–997 [CrossRef]
     [Google Scholar]
  27. Winiecka-Krusnell J., Linder E. 1998; Cysticidal effect of chlorine dioxide on Giardia intestinalis cysts. Acta Trop 70:369–372 [CrossRef]
     [Google Scholar]
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The microaerophilic flagellate Giardia intestinalis: oxygen and its reaction products collapse membrane potential and cause cytotoxicity
Microbiology 146, 3109 (2000); https://doi.org/10.1099/00221287-146-12-3109
/content/journal/micro/10.1099/00221287-146-12-3109
/content/journal/micro/10.1099/00221287-146-12-3109
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