The effect of seed extracts on the antigenicity of LPS. (A) Purified wild-type LPS preparations used to obtain the data in Table 2. LPS was purified after growth in the presence or absence of seed extracts containing anthocyanins, and the LPS was subjected to SDS-PAGE. (B) SDS-PAGE comparison of the LPS in crude phenol-water extracts from strain CE395 and the wild type that had been grown in parallel and, where noted, exposed to the same seed extract. Lanes 1 and 2 in both panels are LPS from wild-type strain CE3. All lanes 3 and 4 are from strain CE395. For all lanes 2 and 4, the bacteria were grown in the presence of seed extract. In each panel the image on the left is of gel lanes stained with silver. (In panel A the gel was stained after being elecroblotted, resulting in barely visible LPS II bands.) On the right in each panel is the blot of these lanes reacted with monoclonal antibody JIM28.