The macrolides (erythromycin, azithromycin, clarithromycin, dirithromycin, troleandomycin, etc.) bind reversibly to the 23S rRNA in the 50S subunit. There is evidence that they may inhibit elongation of the protein by preventing the enzyme peptidyltransferase from forming peptide bonds between the amino acids. They may also prevent the transfer of the peptidyl tRNA from the A-site to the P-site as shown here.
Flash animation illustrating Mode of Action of Macrolides
in Blocking Translation during Bacterial Protein Synthesis: Preventing
the Transfer of the Peptidyl tRNA from the A-site to the P-site.swf
by Gary E. Kaiser, Ph.D. Professor of Microbiology, The Community College of Baltimore County, Catonsville Campus.
This work is licensed under a Creative Commons Attribution 4.0 International License.
Based on a work at http://faculty.ccbcmd.edu/~gkaiser/index.html.
Last updated: September, 2018
Please send comments and inquiries to Dr. Gary Kaiser