TABLE 1.

Effect of overexpression of Int and/or Xis on excision in L. lactis

Plasmid in EFL1103/pEU333	Protein encoded by plasmid	Excision frequency (Cmr CFU/total CFU)
None	NAa	4.5 × 10−8 ± 4.1 × 10−8b
pEU327	Vector	4.3 × 10−8 ± 5.2 × 10−8
pEU329	Int	1.3 × 10−6 ± 1.1 × 10−6
pEU357	Xis	1.3 × 10−7 ± 0.5 × 10−7
pEU354	Int and Xis	9.5 × 10−6 ± 3.6 × 10−6

^aNA, not applicable. 

^bMean ± standard deviation.