23S rRNA methylastransferase leader peptide (ErmCL)
This family consists of several very short bacterial 23S rRNA methylase leader peptide (ErmCL) sequences. ermC confers resistance to macrolide-lincosamide streptogramin B antibiotics by specifying a ribosomal RNA methylase, which results in decreased ribosomal affinity for these antibiotics. ermC expression is induced by exposure to erythromycin and is controlled by an uORF encoding the leader peptide ErmCL. It has been shown that the four C-terminal ErmCL residues I6F7V8I9 are crucial for ribosome stalling and that translation is arrested likely due to the PTC adopting an inactive conformation that prevents peptide bond formation with the incoming Ser-tRNASer at the 10th ermCL codon position.