Figure 2: The active site of PcsB.
From: Structural basis of PcsB-mediated cell separation in Streptococcus pneumoniae
(a) Molecular surface representation of the CHAP domain of PcsB. The catalytic Cys292 is coloured in yellow. The PEG molecule attached to the active site is represented as capped sticks. The length of the active-site groove is indicated by an arrow. (b) Electrostatic potential on the CHAPPcsB molecular surface with the peptide L-Ala-D-isoGln-L-Lys-D-Ala docked in the active site. An acidic patch (coloured in red) stabilizes L-Lys. (c) Domain interactions between the CC domain in chain A (CC-A) with the CHAP domain of chain B (CHAP-B). Colour code as in Fig. 1. White arrow indicates, as in a, the active-site groove.
