Multiple forms of DNA-dependent RNA and polyadenylic acid polymerases from heterotrophically grown Rhodospirillum rubrum

Abstract

Three, two major and one minor, distinct RNA polymerases have been isolated and partially purified from heterotrophically grown Rhodospirillum rubrum, a facultative photosynthetic bacterium. Associated with each of these three enzymes is a distinct polyadenylic acid polyemrase. All of these enzyme activities are dependent on DNA templates and are resistant to rifampicin and streptovaricin. The structural subunit composition, the response to various chemical compounds and DNA templates, and the properties of the products of these enzymes are studied in detail and compared with those of similar enzyme activities from other bacterial systems. Several unique features have been observed in the R. rubrum enzyme systems, such as an uneven incorporation of purine and pyrimidine nucleotides by the RNA polymerases, and the presence of a lag period in the polyadenylic acid polymerase activities.