S. mutans strains expressing the collagen-binding protein (Cnm) on their cell surface exhibit a binding ability for the extracellular matrix; thus, Cnm may be a virulence factor in several diseases such as infective endocarditis [12], aggravated cerebral haemorrhaging [13–15], non-alcoholic steatohepatitis [16], and inflammatory bowel disease [11]. Here, MTM1 is linked to inflammatory bowel disease.