[Bacillus subtilis and streptomycin resistant mutant growth in the medium with saponite]

The influence of dispersed saponite on growth activity of Bacillus subtilis IMV B-7023 and its streptomycin resistant mutant has been shown. The effectiveness of this process depends on the content of dispersed material and phosphate in the medium. It has been found that when B. subtilis is cultured in the medium containing 0.6 g/l PO4(3-) stimulation of bacteria growth is observed, but at a lower concentration (0.1 g/l PO4(3-)) there is a decline in the culture growth activity. At the same time streptomycin resistant mutant is shown to increase growth activity in the growth medium which contains up to 1.0 g/l saponite, regardless of the concentration of phosphate. It is shown that this effect is a consequence of uniformity of surface properties of streptomycin resistant strain of bacteria and similar parent strain at a concentration of 0.6 g/l PO4(3-).