Size variations and correlation of different cell cycle events in slow-growing Escherichia coli

Abstract

Cell lengths were determined at which cell cycle events occur in the slow-growing E. coli B/r substrains A, K and F26. The radioautographic and EM analyses allowed determination of the variation in length at birth, initiation and termination of DNA replication, and initiation of the constriction process and of cell separation. In all 3 substrains the SD increased between cell birth and initiation of DNA replication. From there on, the SD remained relatively constant until cell separation. These observations are consistent with the presence of a deterministic phase during the cell cycle in which the cell sizes at initiation of DNA replication and at cell division are correlated.