Model of Chromosome Replication Gets Upgraded

Abstract

A n Escherichia coli bacterium takes about 40 minutes to replicate its chromosome. Replication is a necessary precursor to cell division, and yet Escherichia coli can divide every 20 minutes. How is this possible? The answer is that, before a round of replication is over, the bacterium has already initiated the next one (or two)—as biologists have known for more than 50 years. But deciphering how exactly replication is initiated has since remained an unresolved central problem in bacterial physiology. Now a theoretical study by Haochen Fu and colleagues from the University of California,