[Viability of Escherichia coli cultures]

In the logarithmic phase of batch cultures of E. coli B and MRE-600, a high percentage (upto 80%) of the cells did not grow. Viability of the cells was estimated by inoculation on plates, in agar drops, and on slides. As was established by mathematical planning experiments, the viability and growth rate of the culture depend on the micro-element composition of the medium.