There are lots of viruses or virus-like particles reported from =
parasitic protozoa but most do not appear to damage the cells as =
far as we can see. (These include the Giardia, Trichomonas, =
Leishmania, Eimeria, Plasmodium, etc. viruses.) One exception is in
Entamoeba histolytica where several transmissible, lytic viruses
were reported in a series of at least seven papers and a review in =
the 1970's. The review is by Diamond et al 1976 Protozoal viruses. =
Adv. Virus Res. 20: 87-112. There were three morphologically
distinct virus-like particles described and they appeared to have =
double stranded nucleic acid genomes. (Most protozoal viruses appear to
have double stranded RNA genomes.) Nothing has been done on the =
Entamoeba viruses since the late 1970's.
With regard to Rhabdoviruses, these have also been described from =
Entamoeba. I have temporarily placed an electron micrograph of what
appears to be one on the Entamoeba website. I would appreciate comments
from any virologists on its identification and also any suggestions
for how I might go about purifying them for further study - they appear =
to be 'exiting' into the culture medium but are probably low in number.
The EM is found at:
(TEM courtesy of Dr. Arturo Gonzalez-Robles, CINVESTAV-IPN, Mexico City)
C. Graham Clark, Ph.D.
Department of Infectious and Tropical Diseases,
London School of Hygiene and Tropical Medicine,
Keppel Street, London WC1E 7HT, England, G.B.
e-mail: g.clark at lshtm.ac.uk
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