Figure 9. Anti-SAP antibodies block SAP and PulA enzymatic activity.

(A) COH1 strain was grown in pullulan and assayed for the capacity to degrade pullulan in the presence of different anti-sera. The effect of specific anti-sera was tested in a dose range between 0.5 and 2%. White circles indicate the effect of a mouse anti-PBS serum; black circles indicate the effect of an antiserum from an unrelated surface-associated protein; black squares indicate the effect of a mouse anti-SAP serum; white triangles indicate the effect of a mouse anti-SAP serum absorbed to a CNBR resin coated with SAP. (B) as in (A) except for testing the inhibitory activity of an anti-SAP serum on GAS SF370 strain.