TABLE 3.

Relative transformation frequencies of two recipient strains with plasmids overexpressing various parB alleles^a

Recipient	Plasmid used for transformation	Transformation frequency with the following selection:
		Pen	PenSm	Pen + IPTG	PenSm + IPTG
DH5α(pGB2)	pGBT30 (vector)	1 (2.37 × 103)	0.89	0.84	0.89
	pKLB1 (ParA)	1 (1.18 × 103)	0.93	1.08	1.06
	pKLB2 (ParB)	1 (1.75 × 103)	1.20	1.10	1.14
DH5α(pABB811) (parS2/3I)	pGBT30 (vector)	1 (1.2 × 103)	0.73	1.00	0.83
	pKLB1 (ParA)	1 (3.6 × 103)	1.00	0.83	0.20
	pKLB2 (ParB)	1 (1.82 × 103)	0.03	0.83	<0.001
	pABB311 (ParBΔ230-290)	1 (2.22 × 104)	0.82	0.84	0.74
	pABB323 (ParBΔ1-18)	1 (1.56 × 104)	0.08	0.88	<0.001
	pABB324 (ParBΔ1-53)	1 (1.43 × 104)	0.84	0.92	0.73
	pABB326 (ParBΔ1-142)	1 (1.58 × 104)	0.98	1.04	0.93
	pABB328 (ParBΔ1-234)	1 (1.52 × 104)	0.78	0.67	0.78
	pABB330 (ParBΔ121-183)	1 (1.84 × 104)	0.90	0.77	0.69
	pABB316 (N-ParBPa-C-KorBRK2	1 (4.2 × 103)	0.38	1.06	<0.001

^aApproximately 1 μg of plasmid DNA was used for each transformation. To estimate the amounts of transformants, we prepared 1:10, 1:100, and 1:1,000 dilutions of the initial transformation mixture. Samples of 100 μl of the initial mixture and the subsequent dilutions were plated on each of the selective plates in repetition. Pen, pencillin; PenS_m, penicillin and streptomycin. IPTG was added to some plates at a concentration of 0.5 mM. The frequencies presented are relative to the number of transformants (indicated in parentheses) obtained on penicillin plates per 1 μg of plasmid DNA. Frequencies in bold type indicate a significant decrease in transformation frequency.