In vitro DNA synthesis in a concentrated yeast lysate.

A system is described in which DNA synthesis can be monitored in a yeast lysate. The observed synthesis has many of the properties of in vivo DNA replication. It is dependent upon replication growing points that were active in vivo. The in vitro synthesis proceeds via low molecular weight intermediates, but these do not mature into larger DNA. There is a specific requirement for rATP. Mitochondrial DNA is also synthesised in this system.