TABLE 1.

Lactococcal strains used in this study

Strain no.	Host	Plasmid	Presence of bacteriocin determinanta						Reference or source
			lLpedA	nLpedA	nLcvaC	lcnCD	nis	Δnis
	FI5876						+		3
FI10038	FI5876						+
		pFI2391		+					This study
		pFI2148				+
FI10054	FI5876						+
		pFII2436			+				This study
		pFI2148				+
	FI7847							+	5
FI9917	FI7847							+
		pFI2391		+					This study
		pFI2148				+
FI10050	FI7847							+
		pFI2436			+				This study
		pFI2148				+
FI9262	FI5876								12
		pFI2126	+
		pFI2148				+

^aA plus sign indicates the presence of a bacteriocin determinant. lLpedA contains the hybrid L-pedA gene preceded by the lactococcin A promoter, nLpedA contains the hybrid L-pedA gene preceded by the nisin promoter, nLcvaC contains the hybrid L-cvaC gene preceded by the nisin promoter, nis contains the nisin gene cluster, and Δnis contains the nisin gene cluster with a frameshift mutation in codon 16 of the nisin structural gene impeding nisin biosynthesis (the sequences of the downstream nisin cluster genes are unaffected).