Bacteria are small single-celled organisms. Bacteria exist almost everywhere on Earth and are vital to the planet’s ecosystems. Some species can live under extreme conditions of temperature and pressure. The human body is full of bacteria, and in fact, is estimated to contain more bacterial cells than human cells. Most bacteria in the body are harmless, and some are even helpful. However, a relatively small number of species can cause disease.

The bacterial ribosome as a target for antibiotics. A large proportion of useful antibiotics exert their antimicrobial effects by blocking protein synthesis on the ribosome. The bacterial ribosome (70S) contains two subunits: the large subunit (50S) and the small subunit (30S). The large subunit contains the 23S and 5S rRNA while the small subunit contains the 16S rRNA. The catalytic site of the ribosome (peptidyl transferase center) is on the large 50S ribosomal subunit. The peptidyl transferase center can facilitate two chemical reactions during the synthesis of a protein, the formation of peptide bonds and hydrolysis of peptidyl-tRNA (pept-tRNA).

Lefamulin (BC-3781) is an orally active antibiotic.

From: Goethe O, Herzon SB, et al. Nat Prod Rep. 2019 Jan 1;36(1):220-247.

Lefamulin inhibits protein synthesis by binding to the peptidyl transferase center of the 50S bacterial ribosome. Therefore, Lefamulin shows inhibitory activity against C. trachomatis, N. gonorrhoeae, and M. genitalium. Lefamulin also shows potent activity against all M. pneumoniae strains. Meanwhile, Lefamulin shows anti-inflammatory effects on the LPS-induced lung neutrophilia mouse model. What’s more, Lefamulin shows antibacterial effects in S. pneumoniae or S. aureus-challenged lung infection mice.

All in all,  Lefamulin is a potent and orally active antibiotic with anti-inflammatory activity. Lefamulin is effective in the research of bacterial infections, such as bacterial pneumonia.


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