Conversion of Escherichia coli RNA polymerase to a template independent enzyme

Preparations of RNA polymerase (E.C.2.7.7.6) from uninfected Escherichia coli, T4 infected Escherichia coli, and Acinetobacter calcoaceticus when centrifuged in sucrose gradients in the absence of magnesium ions gave rise to five peaks, all of which were able to form polymers from ribonucleoside 5'-triphosphates in the absence of template or primer. All of the peaks obtained from the Escherichia coli enzyme appeared to contain the subunit alpha and beta and, in addition, polypeptides which appeared to be derived from the subunit beta.