Fig. 2.

Monitoring ADP-ribosylation by specific and promiscuous ARTs by SDS-PAGE autoradiography. HEK-cell lysates were incubated for 10 min at 37°C with arginine-specific ARTs (ART2.2, SpvB, C2) or non-arginine-specific ARTs (C3stau2, C3bot, PT) in the presence of [³²P]-NAD⁺. Proteins were size-fractionated by SDS-PAGE and visualized by Coomassie staining (a). SDS-resistant, i.e. covalently incorporated, radioactivity was detected by autoradiography (b). While most bacterial ARTs modify a single prominent band, mouse ART2.2 (lane 1) modifies many target proteins. Enzymes used for ADP-ribosylation: Mouse ART2.2 (ART2); Salmonella enterica SpvB toxin (SpvB); Clostridium botulinum C2 toxin (C2); Staphylococcus aureus exoenzyme C3stau2 (C3stau); Clostridium botulinum C3 toxin (C3bot); Pertussis toxin (PT)