Mono-ADP-ribosylates eukaryotic muscle and non-muscle actin on 'Arg-177'. ADP-ribosylation prevents the polymerization of G-actin to F-actin, causing actin filament depolymerization, destruction of the cytoskeleton and cytotoxicity. Does not possess NAD(+)-glycohydrolase activity, unlike most mART enzymes (By similarity). L-arginyl-[protein] + NAD(+) = H(+) + N(omega)-(ADP-D-ribosyl)-L-arginyl-[protein] + nicotinamide Secreted via the type III secretion system 1 (SPI-2 TTSS). In Salmonella spp. the spv gene cluster is encoded on a highly transmissible plasmid. Belongs to the SpvB family.