In vitro characterization of the ergothioneine oxidative catabolic pathway in Actinoplanes missouriensis ATCC 14538

l -ergothioneine is a naturally occurring histidine thio-derivative produced by certain bacterial and fungal species. Plants acquire ergothioneine from soil, while animals ingest it through their diets. Ergothioneine is widely acknowledged for its powerful antioxidant properties, capable of scavenging reactive oxygen and nitrogen species, thereby exhibiting promising applications across various industrial fields such as cosmetics, functional foods, and medicine. The catabolism of ergothioneine in the biosphere is quite diversified, in this study, we successfully analyzed and experimentally characterized an oxidative catabolic pathway of ergothioneine encoded by Actinoplanes missouriensis ATCC 14538. In this pathway, ergothioneine is firstly oxidized into ergothioneine sulfinate under the catalysis of a dioxygenase (PF05995). Then, ergothioneine sulfinate is converted into hercynine by releasing sulfite with an aminohydrolase (SSF51556). Finally, hercynine is transformed into urocanate, a known metabolite in histidine catabolism, by an aromatic amino acid lyase (PF00221). This catabolic pathway is primarily present in Actinobacteria, a group of soil microorganisms that may capable of recycling sulfur of ergothioneine through this pathway.