The LysM (lysin motif) domain is about 40 residues long. It is found in a variety of enzymes involved in bacterial cell wall degradation [1]. This domain may have a general peptidoglycan binding function. The structure of this domain is known [2].

1: Modular design of the Enterococcus hirae muramidase-2 and Streptococcus faecalis autolysin. Joris B, Englebert S, Chu CP, Kariyama R, Daneo-Moore L, Shockman GD, Ghuysen JM; FEMS Microbiol Lett 1992;70:257-264. PMID:1352512

2: The structure of a LysM domain from E. coli membrane-bound lytic murein transglycosylase D (MltD). Bateman A, Bycroft M; J Mol Biol 2000;299:1113-1119. PMID:10843862