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. 1969 Jan;62(1):210–217. doi: 10.1073/pnas.62.1.210

ELECTRON MICROSCOPY OF THE CIRCULAR KINETOPLASTIC DNA FROM TRYPANOSOMA CRUZI: OCCURRENCE OF CATENATED FORMS*

Guy Riou 1,2, Etienne Delain 1,2
PMCID: PMC285975  PMID: 5254103

Abstract

Circular kinetoplastic DNA was fractionated from Trypanosoma cruzi DNA by Hg-Cs2SO4 gradient. Covalantly closed circular DNA was isolated by buoyant density centrifugation in ethidium bromide CsCl density gradients. Electron microscope studies have shown that kinetoplastic DNA molecules are in the form of open and closed circles of contour length 0.45 μ, the smallest known microbial DNA. DNA molecules are also in the form of catenanes consisting of two or more topologically interlocked circular units of the monomer size 0.45 μ. Associations of numerous circles have also been described and confirmed by band sedimentation. Long linear DNA molecules were also seen, their size ranging between 2 and 12 μ. These molecules are free or are attached to associations of circles.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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