Colony growth ofStreptomyces coelicolorA3(2) under conditions of continuous nutrient supply

Abstract

Colony growth of Streptomyces coelicolor A3(2) was studied on a cellophane membrane beneath which was passed a continuous supply of liquid medium. Colony development and differentiation occurred normally but hyphal extension rates and colony radial growth rates were reduced and branch formation was increased in comparison with colonies grown on the same medium solidified with agar. These changes are thought to result from continuous removal of staling compounds which would otherwise suppress branching at the colony margin. Glucose concentrations in the range of 0–1 g · l−1 had little effect on radial growth and branching except at a concentration of 1 g glucose · l−1, at which branching at the colony margin was suppressed. This concentration of glucose did not permit continued growth on solid medium.