B1CTcu5: A frog-derived brevinin-1 peptide with anti-tuberculosis activity.

Tuberculosis (TB) is a devastating infectious disease that causes a high rate of mortality. Drugs with new modes of action are needed to overcome this scenario. Cationic antibacterial peptides can serve as a potential alternative to existing TB drugs as they target the entire bacterial membrane for activity, thereby reducing the probability of development of drug resistance. In this study, we report anti-tuberculosis activity of B1CTcu5, a peptide that belongs to brevinin-1 family of antimicrobial peptides. This peptide possesses potent in vitro inhibitory activity against M. tuberculosis at 12.5 μg/mL but was not active against M. smegmatis. B1CTcu5 successfully eliminated intracellular mycobacteria without inducing cytotoxicity to the human macrophages at the concentrations tested. This peptide can be used as a template to design peptide-based anti-tubercular agents.