Properties of some staphylococcus aureus strains associated with spontaneous l-phase transformation.

Spontaneous L-phase production was found in 7 of 14 investigated Staphylococcus aureus strains. A common characteristic of the strains producing L-phase variants spontaneously was their ability to develop L-colonies on a solid medium with 1.0-1.5% NaCl by the action of methicillin, whereas other strains required higher NaCl concentrations. Further, in 6 of the 7 strains the ability for spontaneous L-phase production was associated with high L-phase productivity in the presence of methicillin. The pattern of alpha-, beta- and delta-hemolysin production in a strain was not correlated to spontaneous L-phase production.