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Science 11 March 1994:
Vol. 263. no. 5152, pp. 1440 - 1443
DOI: 10.1126/science.8128227
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Articles

Science, Vol 263, Issue 5152, 1440-1443
Copyright © 1994 by American Association for the Advancement of Science

articles

Coding of hemolysins within the ribosomal RNA repeat on a plasmid in Entamoeba histolytica

A Jansson, F Gillin, U Kagardt, and P Hagblom

Department of Microbiology, Uppsala University, Sweden.

The pathogenesis of amoebic dysentery is a result of cytolysis of the colonic mucosa by the parasitic protozoan Entamoeba histolytica. The cytolysis results in extensive local ulceration and allows the amoeba to penetrate and metastasize to distant sites. Factors involved in this process were defined with three clones that express hemolytic activities in Escherichia coli. These potential amoebic virulence determinants were also toxic to human colonic epithelial cells, the primary cellular targets in amoebal invasion of the large intestine. The coding sequences for the hemolysins were close to each other on a 2.6-kilobase segment of a 25-kilobase extrachromosomal DNA element. The structural genes for the hemolysins were within inverted repeats that encode ribosomal RNAs.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Ribin, a Protein Encoded by a Message Complementary to rRNA, Modulates Ribosomal Transcription and Cell Proliferation.
M. Kermekchiev and L. Ivanova (2001)
Mol. Cell. Biol. 21, 8255-8263
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