Table 3.

Summary of the mutations to the waterkeeper residue: effects on PPOs′ copper content and diphenolase/monophenolase activity. The modification of copper content and the activities′ rate are described compared to the wild type of the corresponding enzymes.

Waterkeeper residue
Enzyme	Mutant	Diphenolase activity	Monophenolase activity	Copper %	Ref.
AgproPO	Glu364Gln	−14‐fold (dopamine)	‐7.7‐fold (tyramine)	n.i.	[65]
ToPPO2	Glu235Asp	−1.5‐fold (4‐methylcatechol) −3.2‐fold (dopamine)	n.i.	n.i.	[70]
	Glu235Gln	n.d. (4‐methylcatechol and dopamine)	n.i.	n.i.
CgAUS	Glu248Ala	−200‐fold (dopamine: 2.79 s−1)	n.d. (tyramine)	15	[45]
	Glu248Lys	n.d. (dopamine)	n.d. (tyramine)	0

n.d.: no detected activity, n.i.: no information from the particular study, the entry in s⁻¹ refers to the k_cat value.