TABLE 5.

incC2 induction is toxic to E. coli in the presence of a korABF⁺ plasmid

Plasmid 1	Relevant property(ies)	Plasmid 2	Relevant property(ies)	Relative EOPa
				Double selection	Single selection for the indicated plasmid
					incC+b	korB+c
pDB6	Vector	pJAK16	Vector	1.0	1.5	1.3
pDB6	Vector	pRK21985	tacp-incC2+	0.8	1.1	1.5
pRK2300	korA+ korB+ korF+	pJAK16	Vector	1.2	1.2	1.6
pRK2300	korA+ korB+ korF+	pRK21985	tacp-incC2+	4.7 × 10−4	6.2 × 10−2d	1.2 × 10−2d

^aEKA13 was used as the host strain. The relative EOP was calculated as follows: CFU on medium with IPTG/CFU on medium without IPTG. 

^bChloramphenicol. 

^cKanamycin. 

^dLarge majority of colonies have lost the unselected plasmid.