Figure 3.

The structures of (a) Lys-type peptidoglycan and (b) the carboxy-terminal PGRP domain of human PGLYRP-3 complexed with MurNAc-pentapeptide. (a) Lys-type peptidoglycan; two repeating disaccharide units crosslinked by a peptide are shown; the MurNAc-pentapeptide is in red; the arrows represent the direction of the peptide bond; D-isoGln, D-isoglutamine. (b) The PGRP domain has three α helices (red), five β strands (yellow) and coils (cyan); the three disulfide bonds are in purple; MurNAc-pentapeptide is drawn in stick representation, with carbon, nitrogen, and oxygen atoms in green, blue, and red, respectively. N, amino terminus; C, carboxyl terminus. Reproduced with permission from [58].