Kinetic characterization of sporulation in Streptomyces albidoflavus SMF301 during submerged culture

Abstract

We report the first quantitative analysis of the relationship between environmental changes and sporulation of a streptomycete, Streptomyces albidoflavus SMF301, in submerged culture. A chemically defined medium was constructed for sporulation, over lo9 spores ml-l being formed in the submerged batch culture. Kinetic parameters calculated from batch and chemostat cultures showed that specific submerged spore formation rate (qSJ was inversely related to the specific mycelial growth rate (p). The optimum growth rate for submerged spore formation was 005 h-l, when the maximum value of qrpo was 1.0 x lo6 spores g-l h-l. The turnover rate of biomass at maximum growth yield was 0.029 h-I, when 5.6 x lo6 spores were formed from 1 g mycelium. The present quantitative analysis of submerged spore formation using a controlled system opens the way for biochemical and molecular biological studies related t o the morphological differentiation of Streptomyces spp.

pH effects on 10 Streptomyces spp. growth and sporulation depend on nutrients

“…In contrast, on TYG‐agar (medium 2) and its derivative containing minerals of glycerol‐arginine agar (medium 3) instead of yeast extract the sporulation was the best within the acidic pH range. In submerged culture with glucose as a carbon source the optimal sporulation has been detected at pH 7·0, the spore formation being more clearly repressed by alkaline culture pH (Rho and Lee 1994). Glucose has been reported to both repress and activate sporulation.…”

“…1976; Ensign 1978; Glazebrook et al. 1990; Rho and Lee 1994), the production of which is known to be related to the combination of carbon and nitrogen sources (Surowitz and Pfister 1985; Dekleva and Strohl 1987; Madden et al. 1996; Neumann et al.…”

“…Substrates with nitrogen, like dead fungal mycelium, have increased streptomycetes growth in acid soil, where growth of plant pathogenic streptomycetes has been prevented (Kutzner 1986; Locci 1989). Similarly, in chemically defined medium with glucose growth has soon been inhibited without adenine supplementation or pH adjustment to 7·0, both preventing the pH decrease due to the acid production (Surowitz and Pfister 1985; Rho and Lee 1994). The supplementation of CaCO 3 , and subsequent increase in pH has enriched streptomycetes and inhibited or retarded the fungal growth (Kutzner 1986).…”

Production dynamics of extracellular proteases accompanying morphological differentiation of Streptomyces albidoflavus SMF301

“…Spores germinated and elongated to form mycelium when nutrients were abundant, but the mycelium differentiated to form spores when some nutrients were limited (Lee & Rho, 1993;Rho & Lee, 1994). Submerged spore formation was accompanied by the production of TLP and MTP, and was inhibited by the addition of inhibitors of TLP and MTP.…”

“…Strep tomyes albidojavus SMF30 1 produces abundant spores in submerged and solid cultures (Rho e t al., 1992). The physical and chemical properties of submerged spores and aerial spores have been compared (Lee & Rho, 1993), and the kinetics of spore formation reported (Rho & Lee, 1994). To study the possible role of proteases in differentiation, the activities of extracellular proteases in relation to morphological differentiation in submerged and solid cultures were characterized and extracellular proteases in the culture broth of S. albidojavus were purified.…”