KNG1 and infection: The current, unequivocal identification of the chemical nature of the formed kinin peptides—together with the findings that the unfractionated peptide mixtures generated by Sap1-6 and Sap8 from LK interact with B2 receptors (Figure 6)—provides strong support for the hypothesis that these soluble Saps can release biologically active kinins at infection sites, as they are likely to encounter the appropriate amounts of kininogens to be cleaved [47,48].