FIG. 2.

VgrG1 has ADP-ribosyltransferase (ADPRT) activity, which is associated with the presence of the VIP-2 domain. ADPRT assays were performed by using 6-biotin-17-NAD, purified rVgrG proteins, and HeLa cell lysates (A) or recombinant nonmuscle actin (B) as a source of target protein. The reaction mixtures were separated on SDS-12% PAGE gels and electroblotted to nitrocellulose membranes, and the incorporation of biotin-ADP by the target protein was detected by using streptavidin-HRP. The nature of the sample loaded in each lane of the gels is depicted in a table below panel B.