Figure 3

Silver-stained SDS gel showing the migration of sPLA2 group I on native gels. The enzyme was incubated with various components of the reaction mixture in calcium containing buffer as described in Methods. The sPLA2 band (arrowhead) disappeared or was markedly attenuated when the enzyme was pre-incubated with both peptide and substrate (lane 1), but not after incubation with buffer, substrate, or peptide alone (lanes 2, 3, 4). The gels suggested that the peptide could modify the structure and/or binding properties of the enzyme only in the presence of substrate.