A Rhodanese‐Like Enzyme that Catalyzes Desulfination of Ergothioneine Sulfinic Acid

Abstract

Many actinobacterial species contain structural genes for iron‐dependent enzymes that consume ergothioneine by way of O2‐dependent dioxygenation. The resulting product ergothioneine sulfinic acid is stable under physiological conditions unless cleavage to sulfur dioxide and trimethyl histidine is catalyzed by a dedicated desulfinase. This report documents that two types of ergothioneine sulfinic desulfinases have evolved by convergent evolution. One type is related to metal‐dependent decarboxylases while the other belongs to the superfamily of rhodanese‐like enzymes. Pairs of ergothioneine dioxygenases (ETDO) and ergothioneine sulfinic acid desulfinase (ETSD) occur in thousands of sequenced actinobacteria, suggesting that oxidative ergothioneine degradation is a common activity in this phylum.