ISOLATION OF A NEW MODERATELY HALOPHILIC BROAD-SPECTRUM ANTIBIOTIC PRODUCING ACTINOBACTER

Abstract

In a screening program for antibiotic producer rare-actinobacteria from soil of Iran, a novel moderately halophilic actinobacter (Q70) was isolated. The strain had the ability of antibiotic production against methicillin resistant Staphylococcus aureus. Maximum antibiotic production was obtained in the medium containing 10% (w/v) NaCl. The strain Q70 had also activity against Enterococcus faecalis, Bacillus subtilis and Pseudomonas aeruginosa. The antibiotic extracted from fermentation broth had low toxicity (681/3 μg/ml LC50) against Artemia salina in brine shrimp lethality test. The antibiotic produced by strain Q70 had polar structure. The strain Q70 is proposed as a new species with the name of Nocardiopsis iraniensis with considering the significant morphological, physiological, molecular and chemotaxonomical differences between Q70 and other species of Nocardiopsis.