Anti-bacterial activity of two synthesized peptides, RLYLRIGRR-NH2 (peptide A) and RLRLRIGRR-NH2 (peptide B), both of which are based on a putative active site of defensin, an anti-bacterial peptide from the beetle Allomyrina dichotoma, was examined by an macroscopic and histopathologic assessment during the course of an infection in mice inoculated with Methicillin-resistant Staphylococcus aureus (MRSA) in vivo. Both Peptide A and B decreased the mortality of mice inoculated with MRSA. Peptides A and B decreased the macroscopical and histopathological lesions from MRSA infections in mice even seven days after the challenge. Peptide B also decreased the mortality and lesions of mice inoculated with antibiotic-resistant pathogenic E. coli. The results revealed that peptide B could protect the mice from infections with either MRSA or E. coli.
(Research Team for Viral Disease, TEL: +81-29-838-7843)
Reference:
- Yamada et al. (2004) J. Vet. Med. Sci. 66 : 137-142.
- Yamada et al. (2005) J. Vet. Med. Sci. 67 : 1005-1011.
