Figure 5

Structural context of inactivating mutations close to the WWDYG motif. (A) Alignment of bacterial PglB sequences in the region covering the C. jejuni W₄₅₇WDYG₄₆₁ motif to C. jejuni G481. Numbering of ruler according to PglB _{C. lari} , conserved residues shaded, residues shown in B marked by arrows. (B) Position of activity-relevant residues which were identified by epPCR of PglB _Cj in the crystal structure 3RCE of PglB _{C. lari} (bold red) [11]. The WWD residues and conserved Y468 are shown in blue. Non-conserved, mutation-tolerant residue L486 (C. jejuni L480) is shown in black. Backbone structures of the periplasmic domain and membrane domains are shown in grey and dark green, respectively. The bound bound D-Q-N-A-T-p-nitrophenylalanine acceptor peptide is given as atom-coloured ball-stick representation (N = position 0) and the coordinated Mg²⁺ ion is shown in light green.