Bristol University E Coli Genetics Questions Discussion
- Novobiocin is a potent inhibitor of DNA replication in intact Escherichia coli cells.Gellert et al. (1976) Proc. Natl. Acad. Sci. USA 73:4474-4478 studied the effects of novobiocin in a cell free replication system and showed that it inhibited plasmid replication by altering the superhelical tension of the DNA.This could be rescued by the addition of a single protein of ~375 kDa isolated from novobiocin resistant E.coli.
1) What is a “cell free replication system” and how is it possible to use one to study DNA replication in E.coli?
2) Describe the major similarities and differences between DNA replication in E.coli and eukaryotes.
3) Formulate a hypothesis for Gellert et al.’s observations. How would you testt it?