Ciro Santilli 20 minutes in optimal conditions, with a crazy multiple start sites mechanism: E. Coli starts DNA replication before the previous one finished.
Otherwise, naively, would take 60-90 minutes just to replicate and segregate the full DNA otherwise. So it starts copying multiple times.
- biology.stackexchange.com/questions/30080/how-can-e-coli-proliferate-so-rapidly
- stochasticscientist.blogspot.co.uk/2012/02/how-e-coli-grows-so-fast.html
- www.ncbi.nlm.nih.gov/pmc/articles/PMC2063475/ Organization of sister origins and replisomes during multifork DNA replication in Escherichia coli by Fossum et al (2007)