Inhibition of proteolytic activity of periodontal pathogens by casein-derived peptides

The bovine-casein-derived peptide κ-casein (109–137) has been shown to inhibit the major proteases of the periodontal pathogen Porphyromonas gingivalis. The casein peptides αS1-casein (11–23), β-casein (193–209), κ-casein (106–169) and κ-casein (109–137) were analysed for their inhibitory activity against the whole cell proteolytic activity of the three bacterial pathogens highly associated with chronic periodontitis, P. gingivalis, Treponema denticola and Tannerella forsythia. The peptides β-casein (193–209) and κ-casein (106–169) inhibited the major proteolytic activity of all three pathogens, κ-casein (109–137) inhibited P. gingivalis and T. denticola proteolytic activities while αS1-casein (11–23) only inhibited proteolytic activity associated with P. gingivalis. The peptides β-casein (193–209) and κ-casein (106–169) exhibited synergism with Zn2+ in the inhibition of the P. gingivalis Arg- and Lys-specific proteases.