Enlargement of Escherichia coli after bacteriophage infection. II. Proposed mechanism.

Division of Escherichia coli was stopped and mean cellular volume was increased after infection with T-even phage. This host cell enlargement was temperature-dependent, cyanide-sensitive, and stable in the presence of hypertonic medium. Enlargement ceased at about the same time that energy metabolism ceased. Initially, enlargement was accompanied by a decrease in mean cell density. Tritiated 2, 6-diaminopimelic acid was accumulated and incorporated into cold acid-insoluble material at the preinfection rate. These findings suggest that the effect on host cell size is only in part an osmotic phenomenon and that it also reflects continued growth of the surface of the infected cell in the absence of cell division.