Previously, Plovier et al. cloned an outer membrane protein of A. muciniphila, Amuc_1100, into a bacterial expression vector and expressed the protein in E. coli. The purified protein was then delivered to the high-fat diet-induced obese mice via oral gavage and was found that Amuc_1100 protein interacted with TLR2, and partially recapitulates the function of A. muciniphila against obesity and insulin resistance [17]. Here, TLR2 is linked to obesity due to melanocortin 4 receptor deficiency.