Lactococcus cell wall-associated proteinase

Although in vitro, the cell wall-associated proteinase of the Lactococcus starters is quite active on 8-casein (and that from some strains on asl-casein also), in cheese, they appear to act mainly on casein-derived peptides, produced by chymosin from asl-casein or by plasmin from / -casein. 

Cell wall-associated proteinases of Lactococcus can be classified into three groups, Pj-, Pm-, and mixed-type Pptype proteinases degrade /3- but not asi-casein at a significant rate, while Pm-type proteinases rapidly degrade both a- and /3-caseins (S. Visser etal., 1986). The nucleotide sequences... 

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