MACQUARIMICINS, MICROBIAL METABOLITES FROM MICROMONOSPORA .1. DISCOVERY, TAXONOMY, FERMENTATION AND BIOLOGICAL PROPERTIES

A novel series of microbial metabolites were discovered in fermentatio n broths of two soil isolates. Both cultures were identified as strain s of Micromonospora chalcea. Production of the metabolites, named macq uarimicins, was monitored by an HPLC assay. A seven-day fermentation y ielded 27 mg/liter of macquarimicin A. With MICs of 50 to 100 mu g/ml, macquarimicin A has only very low activity against strains of Bactero ides and other anaerobes. Macquarimicin B has inhibitory activity agai nst the leukemia cell line P-388.