[Ultrastructural features of Rhodococcus rubropertinctus and Streptococcus lactis dissociants]

Three Rhodococcus rubropertinctus dissociants (R, S and M) and two Streptococcus lactis dissociants (R and S) were compared using the electron microscopy method of negative contrasting. The cell wall of R.rubropertinctus dissociants had a thickness of 40 nm (R), 30 nm (S) and 20 nm (M). The cell wall of S. lactis dissociants was 35-55 nm (R) and 25-30 nm (S) thick. 1.5-2-fold variations in the thickness of cell walls could account for the different resistance of the dissociants against the action of such external factors as dehydration, antibiotics, UV, elevated NaCl concentrations, etc.