A Ribosomal Peptidase From Escherichia Coli B

Properties of a peptidase present in E. coli ribosomes have been studied. The enzyme is tightly bound to the ribosomes, as indicated by repeated washings and centrifugations, sucrose density gradient centrifugations, and electrophoresis on cellulose acetate. The level of enzyme activity in the 30 S particles is twice that found in the 50 S particles. When the ribosome structure is disrupted by enzymic or chemical means, the peptidase behaves similarly to the bulk of the ribosomal protein.