Abstract
All species and subspecies of the genusNaegleria were subjected to karyotype analysis by contour-clamped homogeneous electric field and transverse alternating-field electrophoresis. The former technique proved to be superior in detecting differences in karyotype. The chromosome pattern of each species and subspecies was found to be distinct. Between 15 and 23 bands were resolved, with chromosome sizes ranging from a few hundred kilobases to about 1.5 Mb. Hybridisation with cloned rDNA identified one band in all species, corresponding to the rDNA plasmid that does not migrate acoording to its molecular weight because it is circular. InWillaertia magna a similar size distribution was found, in contrast toGiardia andEntamoeba, which have only very large chromosomes. Within the pathogenicN. fowleri some strains showed slight differences in chromosome pattern. The karyotype differed more between strains within the subspeciesN. and. andersoni than between the two speciesN. fowleri andN. lovaniensis. The results suggest that karyotype analysis cannot be used to identify aNaegleria species but is useful for stock identification, gene localisation, genetic exchange studies and epidemiological investigation of the pathogenicN. fowleri.
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Abbreviations
- CHEF:
-
contour-clamped homogeneous electric field
- kb:
-
kilobase
- Mb:
-
megabase
- PSG:
-
phosphate-saline-glucose
- REFRDNA:
-
restriction enzyme fragments of repeated DNA
- TAFE:
-
transverse alternating-field electrophoresis
- TBE:
-
TRIS-borate-EDTA
References
Chu G, Volbrath D, Davis RW (1986) Separations of large DNA molecules by contour-clamped homogeneous electric fields. Science 234:1582–1585
Clark CG, Cross GAM (1987) rRNA genes ofNaegleria gruberi are carried exclusively on a 14 kilobase-pair plasmid. Mol Cell Biol 7:3027–3031
Clark CG, Cross GAM (1988) Circular ribosomal RNA genes are a general feature of schizopyrenid amoebae.J Protozool 35:326–329
De Jonckheere JF (1987) Characterization ofNaegleria species by restriction endonuclease digestion of whole-cell DNA. Mol Biochem Parasitol 24:55–66
De Jonckheere JF (1988a) Geographic origin and spread of pathogenicNaegleria fowleri deduced from restriction enzyme patterns of repeated DNA. Biosystems 21:269–275
De Jonckheere JF (1988b)Naegleria andersoni n.sp., a cosmopolitan amocboflagellate, with two subspecies. Eur J Protist 23:327–333
Fulton C (1970) Amoebo-flagellates as research partners: the laboratory biology ofNaegleria andTetramitus Methods Cell Physiol IV:341–476
McLaughlin GL, Brandt FH, Visvesvara GS (1988) Restriction fragment length polymorphisms of the DNA of selectedNaegleria andAcanthamoeba amebae. J Clin Microbiol 26:1655–1658
Moss DM, Brandt FH, Mathews HM, Visvesvara GS (1988) High-resolution poyyacrylamide gradient gel electrophoresis (PGGE) of isoenzymes from fiveNaegleria species. J Protozool 35:26–31
Van der Plogeg LHT (1987) Separation of chromosome-sized DNA molecules by pulsed field gel electrophoresis. Int Biotechnol Lab April:8–16
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De Jonckheere, J.F. Variation of electrophoretic karyotypes amongNaegleria spp.. Parasitol Res 76, 55–62 (1989). https://doi.org/10.1007/BF00931073
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DOI: https://doi.org/10.1007/BF00931073