Calcium and the biological of two Streptomyces species isolated from the rhizosphere of soybean plants [Egypt].
1985
Mohamed Z.K. | Khalil M.S. | Shalaby A.M.
Careful examination of the experimental organisms revealed that they can be identified as Streptomyces violochromogenes and Streptomyces glaucescens. Calcium chloride decreased the permeability of both organisms as indicated by the low total nitrogen content of media compared to the controls. Small doses of calcium nitrate suppressed the permeability of S. violochromogenes but increased that of S. glaucescens whereas the higher doses were stimulatory for both organisms. Calcium chloride increased the accumulation of nitrogen in the biomass of the both organisms. Calcium nitrate had similar effects on S. violochromogenes only without affecting S. glaucescens. The stimulatory effects of calcium gradually faded with incentration. Calcium chloride increased the proteolytic activity in S. violochromogenes media that was apparent in S. glaucescens media only at the larger doses. Calcium nitrate suppressed the proteolytic activity in S. glaucescens media. The cellulolytic activity of both organisms was suppressed by calcium but amylases were initiated in S. glaucescens media. Those of S. violochromogenes were arrested with the lower levels of calcium but the larger doses restored or stimulated their activity.
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