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Vector replication - (Mar/25/2008 )

Can some one tell me whats the prupose of using these in the vector.
for replication of vector in different cell lines or different system but which one is specific for which
F1 Ori
SV40 Ori


ColE1 should be for plasmid replication in E.coli,

SV40 Ori is for plasmid replication in cell lines with SV40 large T antigen.

-Franz K.-

what about the F1 ori?

-Muhammad Umer-

An ori is simply an origin of replication; the F1 ori is the ori for the F1 plasmid. It is not usually species-specific. Go to Novagen's website and have a look at the pETDuet family of expression vectors. Each of the vectors has a different ori, but you can have four different plasmids in the same cell. This is necessary, because apparently each different plasmid type must have a different ori in order to successfully replicate in a cell.


f1 ori is used for the infection of cells with helper phage in order to package ssDNA. Depending on the orientation of the f1 origin, either the (+) or (-) strand will be packaged. Must be used with E. Coli cells with F' episome.