Restructured Lactococcus lactis strains with emergent properties constructed by a novel highly efficient screening system

Table 2 Bacterial strains and plasmids utilized in this study

Item	Genotype of phenotype	References
Strains
E. coli DH5α	Cloning host; F -φ80lacZ∆M15endA1 recA1 endA1 hsdR17 (rK-mK +)supE44 thi-1 gyrA 96 relA1 ∆ (lacZYA⁻argF)U169 deoR λ⁻	[39]
L. lactis N8	Nisin Z producing strain	[40]
L. lactis MG1363	L. lactis subsp. cremoris, plasmid-free derivative of NCDO712	[41]
L. lactis NZ9000 (9k)	MG1363 pepN::nisRK, the original strain	[42]
L. lactis 9k-3	Three fragments (about 50 kb) deletion in L. lactis 9K	[14]
L. lactis 9k-4A	The L4A (about 10 kb) deletion in L. lactis 9k-3	This work
L. lactis 9k-5A	The L5A (about 21.5 kb) deletion in L. lactis 9k-4A	This work
Plasmids
pNZ5319	Cm^r, Em^r, the original vector	[20]
pNZ5319Δ L4A	Cm^r, Em^r, L4-A knock-out vector	This work
pNZ5417	Cm^r, Derivative of pNZ5319; Δery; containing P_nisZ::lacZ	This work
pNZ5417Δ L4A	Cm^r, L4-A knock-out vector	This work
pNZ5417Δ L5A	Cm^r, L5-A knock-out vector	This work
pNZTS-Cre	Em^r, cre gene cloned at the EcoRI and HindIII sites	[19]
pNZ8048	Cm^r	[42]

ISSN: 1475-2859