We next evaluated possible synergistic effect of gavaging microflora-depleted mice with two bacterial species, because these bacterial species exist together in the intestine, because the abundance of both P. falsenii and P. distasonis was increased and the abundance of both B. eggerthii and A. finegoldii was decreased in Pglyrp-deficient mice, and also because monoassociation with single bacterial species in some studies was not sufficient to affect the sensitivity to colitis [26]. Here, PGLYRP1 is linked to colitis.