Fig 1. Bacterial colonization and plasmid stability in the mouse gut.

On day 0, three groups of germ-free mice were inoculated with 10⁸ CFU of MG/pZE1 control strain (carrying p6851 and pZE1 that did not carry the intI1 gene, n = 4) (A), MG/intI1 strain (carrying p6851 and pZE1intI1 allowing the expression of intI1 SOS-regulated, n = 4) (B) or MG/intI1* strain (carrying p6851 and pZE1intI1* allowing the constitutive expression of intI1, n = 3) (C). Bacterial colonization in the mouse gut was monitored by counting the CFU/g of faeces on non-selective medium (MG1656). Plasmid stability was evaluated by counting the CFU/g of faeces on selective media supplemented with kanamycin (p6851) or ampicillin (pZE1, pZE1intI1 and pZE1intI1*). Symbols represent the average of the CFU/g of faeces per day and error bars indicate the SD.