4.1. Plasmid Constructions and Site-Directed Mutagenesis

To produce recombinant proteins, previously made pET28a-AtGOX1, pET28a-AtGOX2 and pET28a-ZmGO1 expression plasmids [34] were used as templates to introduce point mutations using specific primers pairs (Table S1) and the QuikChange^® II XL site-directed mutagenesis kit (Agilent^®, Les Ulis, France), according to the manufacturer’s instructions. This strategy generated T4V, T4D, T158V, T158D, S212A, S212D, T265A, T265D (AtGOX1 and AtGOX2) and T5V, T5D, T159V, T159D, S213A, S213D, T266A, T266D (ZmGO1) mutated proteins. All constructions were subsequently verified by DNA sequencing using T7 and T7-term primers (Table S1).