Information on EC 1.14.99.51 - hercynylcysteine S-oxide synthase

Requires Fe²⁺ for activity. The enzyme, found in fungal species, is part of a fusion protein that also has the the activity of EC 2.1.1.44, L-histidine N^α-methyltransferase. It is part of the biosynthesis pathway of ergothioneine. The enzyme can also use L-selenocysteine to produce hercynylselenocysteine, which can be converted to selenoneine.