SUMO1 and infection: To then see whether the findings obtained in vitro may transpose in vivo, we analyzed the SUMO patterns in the gut of newborn mice after 180 min infection with Shigella. A decrease in the amount of SUMO1-modified proteins together with an increase in free SUMO1 was clearly visible in mice infected with the invasive strain M90T compared to control or mxiD-infected animals (Figure 1H).