Hfr strain | definition of Hfr strain by Medical dictionary
HFR strain , Hfr strain
a strain, or clone, in which a conjugative plasmid (such as an F'), integrated in the bacterial genome, is instrumental in the transfer (along with plasmid DNA) of integrated bacterial DNA in a sequential manner to a suitable recipient.
[high freguency of recombination]
Hfr strain a strain of a bacterium, typically Escherichia coli, that has the ability to transfer a chromosome to an F- cell and shows a H igh f requency of r ecombination. The F PLASMID (F FACTOR) is integrated into the chromosome of the Hfr cell. Different Hfr strains will have the F plasmid integrated at different sites in the chromosome.