This domain is found in the putative N-acetylmuramoyl-L-alanine amidase cwp6 from Clostridioides difficile and similar proteins from firmicutes. Cwp6, which is involved in cell wall remodelling, consists of five domains: an N-terminal (this entry), a trimer of CWB2 (Pfam:PF04122) and a C-terminal (Pfam:PF01520). This domain, which locates at the bottom of the molecule, folds into a seven-stranded beta-barrel with one alpha-helix and with two additional short beta-strands [1].

1: The CWB2 Cell Wall-Anchoring Module Is Revealed by the Crystal Structures of the\tClostridium difficile Cell Wall Proteins Cwp8 and Cwp6. Usenik A, Renko M, Mihelic M, Lindic N, Borisek J, Perdih A, Pretnar G, Muller U, Turk D; Structure. 2017;25:514-521. PMID:28132783