Bistable growth pattern of Streptomycetes during continuous cultivation in chemostat

Abstract Streptomycetes continuously cultivated in a chemostat exhibit a bistable growth pattern characterized by two different growth behaviours, a “disperse” one and a “pellet” one. There exists a distinct range of growth rates within which either growth behaviour can be exerted. The transition between them can be induced by shifting the growth rate above or below critical values by manipulating the dilution rate. Both of them are stable over the same range of growth rates provided that the changing of growth rate within this stability range proceeds successively in moderate steps. This bistable growth pattern is exerted at least by two different species, Streptomyces noursei and Streptomyces “lividans”.