Integration of the receptor for bacteriophage lambda in the outer membrane of Escherichia coli: coupling with cell division

Abstract

Induction of the synthesis of the receptor for phage λ is obtained by adding maltose and adenosine 3' 5' cyclic monophosphate to glucose grown cells of E. coli. Bacteria induced for a short period of time were infected with a high multiplicity of phage λ, and examined by electron microscopy. Only a fraction of the bacteria were seen to have adsorbed a large number of phage particles. The majority of such bacteria had a constriction indicating formation of a septum and, in this case, the density of adsorbed particles was highest in the vicinity of the constriction. When found on bacteria showing no sign of septum formation, the adsorbed particles were assymmetrically distributed, one pole of the bacteria being more heavily covered with phage particles than the other. Such asymetrically covered bacteria are believed to have originated from cells which divided during the induction period. The results suggest that the receptor for phage λ, a protein of the outer membrane, is integrated in the cell envelope during the last quarter of each generation and that the integration process is initiated in the vicinity of the forming septum.