Abstract: A method for producing ergothioneine or a related substance, where the method includes culturing a microorganism having an ergothioneine biosynthetic gene with an increased adenosine kinase (Adk) activity, and collecting the ergothioneine, a related substance thereof, or a mixture thereof from the medium obtained by the culture or the bacterial cells.

Abstract: In a composition in which L-ergothioneine (EGT) and N,N-dimethyl-L-2-thiohistidine (DTH), it makes possible to suppress coloring of the composition. A composition comprising EGT and DTH is prepared in which the content of DTH is reduced.

Abstract: A method for producing ergothioneine at a low cost in large quantities and a bacterium for use in said method are provided. A method for producing ergothioneine or a related substance thereof, or a mixture thereof, comprising culturing a bacterium belonging to the family Enterobacteriaceae having the ergothioneine-producing ability in a culture medium, and collecting ergothioneine or a related substance thereof, or a mixture thereof, from the culture medium or from the cells obtained by culture, wherein said bacterium is the one which is modified so as to have a reduced activity of a protein comprising a core sequence region comprising 5 amino acid residues: Ser-Arg-Gly-Arg-Thr (SEQ ID NO:7) as a part thereof; and a bacterium belonging to the family Enterobacteriaceae having the ergothioneine-producing ability modified so as to have a reduced activity of a protein comprising a core sequence region comprising 5 amino acid residues: Ser-Arg-Gly-Arg-Thr (SEQ ID NO:7) as a part thereof.

Abstract: A method for producing ergothioneine at a low cost in large quantities and a bacterium for use in said method are provided. A method for producing ergothioneine or a related substance thereof, or a mixture thereof, comprising culturing a bacterium belonging to the family Enterobacteriaceae having the ergothioneine-producing ability in a culture medium, and collecting ergothioneine or a related substance thereof, or a mixture thereof, from the culture medium or from the cells obtained by culture, wherein said bacterium is the one which is modified so as to have a reduced activity of a protein comprising a core sequence region comprising 5 amino acid residues: Ser-Arg-Gly-Arg-Thr (SEQ ID NO:7) as a part thereof; and a bacterium belonging to the family Enterobacteriaceae having the ergothioneine-producing ability modified so as to have a reduced activity of a protein comprising a core sequence region comprising 5 amino acid residues: Ser-Arg-Gly-Arg-Thr (SEQ ID NO:7) as a part thereof.