Abstract
Multicellular cells were efficiently induced in Staphylococcus haemolyticus by the addition of protease to exponentially growing cultures at 30C. Electron microscopy revealed the formation of tetrad-shaped multicells that were septated but not separated from each other. Incubation of the multicells with extract from the cells grown without protease resulted in a fourfold increase in the number of colony-forming units as compared with the untreated control. An electrophoretic analysis showed that protease caused a loss of cell wall-lytic activity of the cell, which possibly led to the formation of multicells through cessation of cross wall separation.