Lactococcus

Lactococcus is a lactic acid bacterial genus of five major species formerly included as members of the genus Streptococcus Group N and related species. Gram-positive, they are typically spherical or ovoid, 0.5–1.2 µm by 0.5–1.5 µm, and occur in pairs and short chains. They are non-spore forming and are not motile. The type species for the genus is L. lactis which in addition have two subspecies lactis and cremoris. Lactococcus differ from other lactic acid bacteria as they have pH, salt and temperature tolerances for growth.

Lactococcus is commonly used in the dairy industry in the manufacture of fermented dairy products like cheeses. They can be used in single strain starter cultures, or in mixed strain cultures with other lactic acid bacteria such as Lactobacillus and Streptococcus.