Related Experiment Video
Updated: Aug 16, 2026

Site-specific Bacterial Chromosome Engineering: ΦC31 Integrase Mediated Cassette Exchange (IMCE)
Published on: March 16, 2012
A small derivative of the broad-host-range plasmid RK2 which can be switched from a replicating to a non-replicating
P Karunakaran1, D T Endresen, H Ertesvåg
1UNIGEN Center for Molecular Biology and Department of Biotechnology, Norwegian University of Science and Technology, 7489, Trondheim, Norway.
Abstract:
TrfA is the only plasmid-encoded protein required for RK2 replication. We report here the construction and characterization of an RK2-based vector in which trfA is expressed from the inducible promoter Pm. The resulting construct, pJBSD1, was found to replicate in Escherichia coli DH5a (recA(-)) only in the presence of a Pm inducer. In two tested E. coli recA(+) strains pJBSD1 could replicate in the absence of inducer, but a replication inducer-dependent phenotype was obtained in these strains by introducing a mutation known to reduce the trfA expression level. The plasmid construct could be used as a conditional suicide vector system for targeted chromosomal integration via homologous recombination. This feature may potentially be used for many types of studies in microbial molecular biology.
Related Concept Videos
Conservative Site-specific Recombination and Phase Variation
The recognition sites for Cre recombinase called LoxP...
Repressible Operon: trp Operon
Plasmids
Mechanism of Conjugation
Viral Replication: Lysogenic Cycle
DNA Bacteriophages

