Glucose-stimulated acidogenesis by Streptomyces peucetius

Abstract
Cultures of Streptomyces peucetius often were observed to divert spontaneously from the production of anthracycline antibiotics to the excretion of acidic metabolites, whether grown in a defined medium or a nutrient-rich medium. The predominant excreted acidic metabolites were determined by high-performance liquid chromatography to be pyruvate and 2-oxoglutarate. The acidification occurred at high frequencies when glucose was the primary carbon source in a defined medium, at intermediate frequencies when fructose was the primary carbon source, and did not occur when either maltose, starch, or dextrin were used as primary carbon sources.