Figure 2

Engineering the acidic-pH stable MnP6 from C. subvermispora by introducing a catalytic tryptophan (S168W variant) and changing the tryptophan environment (S168W-environment variant). The two variants were built by substituting Ser¹⁶⁸ of C. subvermispora MnP6 (A) by a catalytic tryptophan to obtain the S168W variant (C) and engineering its environment as found in P. ostreatus VP1 (B) to obtain the S168W-environment variant (D). The mutated residues in C (Trp¹⁶⁸) and D (Ser¹⁶², Trp¹⁶⁸, Glu²⁵⁸, Met²⁶², Lys²⁶⁸, Asn²⁷¹, Arg²⁷², and Gly²⁷⁵) are in italics. Based on MnP6 (4CZN) and VP1 (4BLK) crystal structures, and homology models of the S168W and S168W-environment variants.