Table 1.

Lactococcus lactis strains used in this study

Strain	Comment(s) (reference)
L. lactis M78	Strain under investigation; isolated from Greek raw milk (35)
L. lactis M104	Strain under investigation; isolated from Greek raw milk (35)
L. lactis subsp. lactis LMG 6890T	Type strain
L. lactis subsp. cremoris LMG 6897T	Type strain
NCFB = NCDO 1402, L. lactis subsp. lactis	Nisin-producing (Nis+); nisin resistant; lactose and sucrose positive; proteinase negative; was among the Nis+ strains evaluated as starters in Cheddar cheese manufacture during the early 1990s (16); kindly provided by the Leatherhead Food Research Association (LFRA; Surrey, United Kingdom) microbiology laboratory for use as a bacteriocin-positive (Nis+) control strain indicator in our previous sakacin B studies (48)
F1 L. lactis subsp. lactis	Nis+, proteinase negative; sucrose-positive but lactose-negative strain, like NCFB 912, NIZO R5L0, and a few other natural Nis+ L. lactis subsp. lactis strains (15); recovered as a “contaminant” from a stock culture of NCFB 1402; thus, F1 is either a lactose-negative variant of NCFB 1402 or a strain like NCFB 912 since exptl Cheddar cheese trials with mixed Nis+ L. lactis/cremoris starter strains, such as those performed in the United States (14), were conducted also at the LFRA
CNRZ 125 L. lactis subsp. lactis	Strain of dairy origin provided by INRA, Jouy-en Josas, France
CNRZ 258 L. lactis subsp. lactis	Strain of dairy origin provided by INRA, Jouy-en Josas, France
CNRZ 301 L. lactis subsp. lactis	Strain of dairy origin provided by INRA, Jouy-en Josas, France
CNRZ 1075 L. lactis subsp. lactis	Strain of dairy origin provided by INRA, Jouy-en Josas, France
1L8 L. lactis subsp. cremoris	Raw cow milk isolate provided by INRA, Poligny, France