%0 Journal Article %A Uchida, Ikuo %A Ishihara, Ryoko %A Tanaka, Kiyoshi %A Hata, Eiji %A Makino, Sou-ichi %A Kanno, Toru %A Hatama, Shinichi %A Kishima, Masato %A Akiba, Masato %A Watanabe, Atsushi %A Kubota, Takayuki %T Salmonella enterica serotype Typhimurium DT104 ArtA-dependent modification of pertussis toxin-sensitive G proteins in the presence of [32P]NAD %D 2009 %J Microbiology, %V 155 %N 11 %P 3710-3718 %@ 1465-2080 %R https://doi.org/10.1099/mic.0.028399-0 %K PTX, pertussis toxin %K PNS, post nuclear supernatant %K MTC, mitomycin C %K LTX, heat-labile enterotoxin %K CHO, Chinese hamster ovary %K DT, definitive phage type %K CTX, cholera toxin %I Microbiology Society, %X Salmonella enterica serotype Typhimurium (S. Typhimurium) definitive phage type (DT) 104 has become a widespread cause of human and other animal infections worldwide. The severity of clinical illness in S. Typhimurium DT104 outbreaks suggests that this strain possesses enhanced virulence. ArtA and ArtB – encoded by a prophage in S. Typhimurium DT104 – are homologues of components of pertussis toxin (PTX), including its ADP-ribosyltransferase subunit. Here, we show that exposing DT104 to mitomycin C, a DNA-damaging agent, induced production of prophage-encoded ArtA/ArtB. Pertussis-sensitive G proteins were labelled in the presence of [32P]NAD and ArtA, and the label was released by HgCl2, which is known to cleave cysteine-ADP-ribose bonds. ADP-dependent modification of G proteins was markedly reduced in in vitro-synthesized ArtA6Arg-Ala and ArtA115Glu-Ala, in which alanine was substituted for the conserved arginine at position 6 (necessary for NAD binding) and the predicted catalytic glutamate at position 115, respectively. A cellular ADP-ribosylation assay and two-dimensional electrophoresis showed that ArtA- and PTX-induced ADP-ribosylation in Chinese hamster ovary (CHO) cells occur with the same type of G proteins. Furthermore, exposing CHO cells to the ArtA/ArtB-containing culture supernatant of DT104 resulted in a clustered growth pattern, as is observed in PTX-exposed CHO cells. Hydrogen peroxide, an oxidative stressor, also induced ArtA/ArtB production, suggesting that these agents induce in vivo synthesis of ArtA/ArtB. These results, taken together, suggest that ArtA/ArtB is an active toxin similar to PTX. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.028399-0