Lysis of methicillin-resistant Staphylococcus aureus by 2,4-diacetylphloroglucinol produced by Pseudomonas sp AMSN isolated from a marine alga

Previously 2,4-diacetylphloroglucinol (DAPG) produced by Pseudomonas sp. AMSN isolated from a marine alga, had demonstrated a high level of anti-methicillin-resistant Staphylococcus aureus (MRSA) activity comparable with that of vancomycin. In this study, this substance had bacteriolytic activity against MRSA at 1 mg/l as well as similar activity against Vibrio parahaemolyticus at 24 mg/l that suggests a novel antibacterial mode of action by this substance. Heat and pH stability tests showed it to be stable at temperatures ranging from 35 to 70 degreesC and at pHs ranging from 2-7. It was not acutely toxic to mice at levels up to 100 mg/kg. (C) 2002 Elsevier Science B.V. and International Society of Chemotherapy. All rights reserved.