The antimicrobial peptide Ci-MAM-A24 is highly active against multidrug-resistant and anaerobic bacteria pathogenic for humans.

Ci-MAM-A24, a synthetic antimicrobial peptide derived from a peptide precursor from immune cells of the marine invertebrate Ciona intestinalis, has been shown to be potently active against representatives of Gram-positive and Gram-negative bacteria by permeabilising their cytoplasmic membrane. In the present study, the activity of Ci-MAM-A24 against different bacterial pathogens frequently causing therapeutic problems was tested. In particular, the killing capacity of Ci-MAM-A24 against clinically important anaerobic bacteria as well as multiresistant aerobic strains such as meticillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci, extended-spectrum beta-lactamase-producers and multiple-resistant Pseudomonas aeruginosa strains was monitored. Virtually all strains proved to be highly susceptible to Ci-MAM-A24 at low concentrations [minimum bactericidal concentration (MBC)<10 microg/mL]. Copyright (c) 2010 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.