IDENTIFICATION OF AN ALKALINE-DEPENDENT STREPTOMYCES AS STREPTOMYCES CAERULEUS BALDACCI AND CHARACTERIZATION OF THE SPECIES UNDER CONTROLLED CONDITIONS

Abstract

The identity of the Streptomyces which produces the new crystalline antibiotic, caerulomycin, was determined. The distinctive characteristics of the culture are: produces a blue-to-red indicator pigment; requires a neutral or alkaline reaction for growth; bears oblong to cylindrical spores in straight and flexuous chains; is not chromogenic on peptone media but produces hydrogen sulphide on iron-peptone agar; and does not grow on unbuffered potato or carrot plugs, Difco litmus milk, ASA agar, or Pridham and Gottlieb's synthetic agar medium. The culture readily utilizes glucose, fructose, galactose, mannitol, sucrose, xylose, starch, and maltose but does not utilize, or utilizes to a limited extent, mannose, i-inositol, adonitol, lactose, ribose, raffinose, and cellulose.A direct comparison with authentic cultures of Streptomyces coelicolor and Streptomyces caeruleus proved the unknown to be qualitatively indistinguishable only from the latter. A literature survey did not reveal other species resembling the unknown, which was therefore concluded to be a member of Streptomyces caeruleus Baldacci.The original description of S. caeruleus is amended and some characteristics of the culture grown under reproducible conditions are reported.