Figure 3. Association of aminoacylation activities with the protein synthesis machinery.
T. kodakarensis cells were grown under anaerobic conditions to mid log phase and then subjected to polysome analysis. Polysome lysates were fractionated by sucrose gradient centrifugation and the ribosomal subunits, monosomes and polysome fractions collected. A, absorbance profile (A254) of fractions eluted from the gradient. The top of the gradient is on the left and peaks representing the 30S and 50S ribosomal subunits, monosomes and polysomes are denoted. B, Leu-tRNA aminoacylation activity in ribosomal subunits, monosomes and polysomal fractions (P1 and P2). C, Aminoacylation activities associated with 50S ribosomal subunits.