Figure 10.

The active site environment of AGAO and LOXL2. (A) TPQ resides in between the Cu²⁺− and O₂−binding sites (in light blue and in grey) and the substrate−binding site/entry channel (in dark blue). A hydrogen−bonding interaction between O4 (oxoanion) of TPQ and Tyr284 (in blue line) limits the mobility of TPQ [11]. (B) TPQ−2HP detected in WT−ECAO [26]. The residue numbering was edited to match with those of AGAO. (C) TPQ−2HP ligated on Cu²⁺ detected in Y284F−ECAO where Cu²⁺−ligation generates dianion of TPQ−2HP [29]. The residue numbering was edited to match with those of AGAO. (D) Formation of LTQ−2HP (azo) mono−anion by ligating to the active site Cu²⁺.The 2HP (X=N) adduct ligates to the active site Cu²⁺ but the PH (X=C) adduct does not. W: water molecule.