ISSN:
1550-7408
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
Notes:
SYNOPSIS. The distribution of cytoplasmic DNA as determined by H3-thymidine incorporation in the Fernald strain of Hartmannella rhysodes was studied by electron microscope autoradiography. Of a total of 1,313 silver grains counted over the cytoplasm in thin sections, 488, 271, 202 and 230 were attributed to DNA in mitochondria, cytoplasmic matrix, plasmalemma and ectoplasm, respectively. On the basis of the ratio of grains associated with the relative area occupied by the various compartments, the plasmalemma accounted for 3 times more grains than the mitochondria and about 20 times that attributed to DNA in cytoplasmic matrix and ectoplasm. These findings are interpreted to indicate the presence of endosymbionts in this strain of soil amoeba. Since no definitive microorganism could be seen in this cell, the most likely endosymbiont is defective DNA virus(es) or episome-like genetic element(s).
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1550-7408.1969.tb02322.x
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