NUCLEIC-ACIDS IN PHOTOSYSTEM-II REACTION CENTER PREPARATIONS EXTRACTED USING THE DETERGENTS CHOLATE AND DERIPHAT

Observations indicating the presence of nucleic acids in photosystem II reaction center preparations are described: a) phenol and chloroform extraction produced a material with an absorption spectrum similar to that of nucleic acids; b) agarose gel electrophoresis followed by staining with ethidium bromide produced a fluorescent band with a mobility close to that of bromophenol blue; c) the absorption of the extract at 260 nm increased on heating, as occurs when small nucleic acid molecules are melted; d) treatment of photosystem II reaction centers with streptomycin sulfate produced a precipitate, and the supernatant completely lost photochemical activity. These results suggest that nucleic acids may be present in the form of nucleoprotein complexes with pigments.