TRANSCRIPTIONAL AND SEDIMENTATION PROPERTIES OF RIBONUCLEIC ACID POLYMERASE FROM MICROCOCCUS LYSODEIKTICUS

Ribonucleic acid polymerase has been prepared from Micrococcus lysodeikticus and Escherichia coli, and several properties of these two similar enzymes have been examined. Whereas the E. coli enzyme exhibits both fast and slowly sedimenting forms, depending upon salt concentration, the M. lysodeikticus enzyme shows only a slowly sedimenting form in solutions of both low and high ionic strength. Purified M. lysodeikticus ribonucleic acid polymerase may transcribe intact deoxyribonucleic acids asymmetrically under appropriate reaction conditions. The degree of symmetry of the deoxyribonucleic acid directed ribonucleic acid synthesis is a function of several factors including the choice of template deoxyribonucleic acids. With ϕX174 RF deoxyribonucleic acids as template the concentration of KCl, MgCl2, and spermidine in the reaction system markedly influences strand selection by the M. lysodeikticus enzyme. With T4 deoxyribonucleic acid as template, however, these reagents appear to have little effect on the type of transcription. © 1969, American Chemical Society. All rights reserved.