Aspects of the relation between Cyanophora paradoxa (Korschikoff) and its endosymbiotic cyanelles Cyanocyta korschikoffiana (Hall & Claus) - IV. The effects of rifampicin, chloramphenicol and cycloheximide on the synthesis of ribosomal ribonucleic acids and chlorophyll

The effects of the antibiotics rifampicin, cycloheximide, and chloramphenicol on ribosomal RNA synthesis in Cyanophora paradoxaand its endosymbiotic cyanelles, Cyanocyta korschikoffiana, were examined. Rifampicin inhibited synthesis of the cyanelle 23S and 16S r-RNA. Chloramphenicol had a similar, though less marked, effect. By contrast, cycloheximide appeared to inhibit synthesis of only the host’s 25S and 18S r-RNA. Neither rifampicin nor chloramphenicol had as marked an inhibitory effect on chlorophyll synthesis as did cycloheximide.