In situ microspectrofluorometry of nuclear and kinetoplast DNA in Trypanosoma gambiense.

Using a spectrofluorometer with the Zeiss Universal Micro-Spectrophotometer 1 (UMSP 1), both nuclear and kinetoplast DNA (N-DNA and K-DNA) in the trypomastigote form of Trypanosoma gambiense (Strain Wellcome) were measured in situ without being extracted. As the fluorescent dye, ethidium bromide was preferably employed because there was a very marked increase in the ethidium fluorescence when the dye was intercalated between the base paires of the DNA helix. According to this method, it became possible to demonstrate the existence of double-stranded DNA in both nucleus and kinetoplast clearer than before.