Fig. 1.
Biochemical characterization of the M. thermautotrophicus 50S ribosomal subunit. (a) Ribosome profiles from M. thermautotrophicus crude ribosomes applied onto high and low magnesium and monovalent salt 10–40% (w/v) sucrose gradients. Under both associating (left) and dissociating (right) conditions, only 30S and 50S peaks, but no 70S peaks, were observed. (b) Mass spectrometric analysis of M. thermautotrophicus ribosomes. Large ribosomal subunit proteins are printed in black, aIF6 in bold italics, and proteins most likely co-sedimenting with the 50S subunit unspecifically or due to 30S contamination in gray.