Stable Ribonucleic Acid Synthesis during the Cell Division Cycle in Slowly Growing Escherichia coli B/r

The rate of synthesis of stable nucleic acid was measured during the division cycle in slowly growing cultures of Escherichia coli B/r. The experimental patterns of synthesis were consistent with a discontinuous mode of chromosome replication and an exponentially increasing rate of stable RNA synthesis. The rates of tRNA and rRNA synthesis relative to the rate of total stable RNA synthesis were constant during the cell division cycle and were not affected by replication of stable RNA cistrons.