Figure 1

Cell cycle events and chromosome structure. Cell cycle events and chromosome shapes relative to cell age in strains CMT931, CMT935, and CMT936 growing in glycerol minimal medium at 37°C. τ is the doubling time in minutes. C is the time in minutes required to replicate the chromosome. Thick bars represent replicating chromosomes. Time refers to the length in minutes of each of the three periods determined by cell birth (b), initiation of replication (i), termination of replication (t), and cell division (d). cells is the frequency of cells, in percentages, in each of the three periods. RF/cell is the number of replication forks per cell, and foci/cell is the expected number of foci per cell of a fluorescent replication protein depending on the association state of the sister replication forks, in each of the three cell cycle periods. The inset shows the symbols for the origin of replication (small black circle), for each replication fork (open circle), and for the foci of an immunostained replication protein (grey oval).