[Structure and development of zone-forming colonies of Streptomyces levoris]

The structure of Streptomyces levoris colonies was studied in the course of growth on media containing various energy and carbon sources. Hyphae of the primary substrate mycelium underwent periodic differentiation yielding secondary structures which, apparently, were involved in the formation of sporogenous aerial mycelium rings on the surface of the colonies. The data of histological studies, luminescent microscopy and in vivo observations are discussed in terms of how processes of growth and zone formation are separated in space and time.