Lytic effect of trypsin, lysozyme, and complement on Treponema pallidum.

The lysis of several strains of cultured spirochaetes, during incubation in guinea-pig serum, is dependent upon the presence of active complement and lysozyme (Nevin and Guest, 1967). Treponema pallidum, however, is not lysed readily in guineapig serum, although motile cells are immobilized more rapidly when crystalline lysozyme is added to suspensions containing serum from syphilitics and active guinea-pig serum (Kent and deWeerdt, 1963; Metzger, Hardy, and Nell, 1961). Similarly, several varieties of Treponemataceae are disrupted by the action of pepsin and trypsin (Bradfield and Cater, 1952; Swain, 1955) whereas T. pallidum, while susceptible to pepsinization, apparently loses only an outer covering as a result of tryptic digestion