DNA-dependent RNA and polyadenylic acid polymerase from phototrophically grown Rhodospirillum rubrum

Abstract

DNA-dependent RNA and polyadenylic acid polymerases have been purified from phototrophic Rhodospirillum rubrum. Their properties have been found to be very similar to those of the previously reported heterotrophic R. rubrum enzymes. However, several important differences do exist between the enzymes from the phototrophic and the heterotrophic cells, such as the lack of response to added polyadenylic acid for poly A synthesis and the presence of the σ subunit in the phototrophic enzymes. Furthermore, additional purification steps were necessary for preparation of phototrophic enzyme fractions with high DNA-dependence.