FIG. 5.

Electrophoresis of VP4, VP5CT, and VP8CT. (A) Coomassie blue-stained SDS-polyacrylamide gel. Purified proteins were denatured with SDS-PAGE sample buffer containing 1% β-mercaptoethanol and either boiled or not boiled (indicated above brackets) prior to separation on a 4-to-15% polyacrylamide gradient gel. Lane MW, molecular mass standards (in kilodaltons); lanes 4, VP4; lanes 5, VP5CT; lanes 8, VP8CT. (B) Coomassie blue-stained native polyacrylamide gel. Shown are purified proteins in TNE electrophoresed on a 4-to-25% polyacrylamide gradient gel with a discontinuous native buffer system (described in Materials and Methods). Lane M, native PAGE markers; LDH, lactate dehydrogenase; BSA, bovine serum albumin. Samples are labeled as in panel A. (C) Coomassie blue stained IEF gel. Purified proteins in TNE were applied to the cathode end of a polyacrylamide gel containing carrier ampholytes in the pH range 4 to 6.5. Markers were applied either at the cathode end (cat) or in the middle of the gel (mid), as indicated above the lanes. IEF was performed until the markers applied at either location had focused to the same position. The pI of each marker is indicated adjacent to the corresponding band, and the position of the cathode is indicated. Samples are labeled as in panel A.