ChemInform Abstract: Anthracimycin, a Potent Anthrax Antibiotic from a Marine‐Derived Actinomycete.

Abstract

The human infectious disease anthrax is caused by the sporeforming, Gram-positive bacterium Bacillus anthracis. The disease, which is most common in those that handle infected farm animals, has also been used as a bioterrorism weapon. In 2001, just a week after the World Trade Center attacks, anthrax was deliberately spread through the US postal system by sending letters with powdered B. anthracis spores. This caused 22 cases of anthrax infection and ultimately claimed five lives. [1] Depending upon the method of exposure (inhalation of spores and direct bacterial contact, among others) B. anthracis infections can require prolonged treatment often for six months with a variety of antibiotics. The pulmonary form of anthrax is considered a medical emergency that may require continuous intravenous therapy with potent antibiotics. In the event of a bioterrorism attack, individuals exposed to B. anthracis will be given antibiotics prior to the onset of the illness. A vaccine has been developed but is not yet available to the general public. [2] Given the severity of this disease, and the fact that it can be spread by aerosol dispersal, the development of effective new antibiotics remains a high priority. As a resource for developing microbial antibiotics, we have focused our efforts on marine microorganisms, particularly those that are in the deep oceans. Examination of a Streptomyces species (our strain CNH365), isolated from near-shore marine sediments found near Santa Barbara, CA, showed that culture extracts possessed significant activity against B. anthracis and methicillin-resistant Staphylococcus aureus in broth dilution assays. Subsequent fractionation of the extract following antibacterial activities yielded a pure