Kikkoman Corporation

Keiichi Ichikawa

Seiichi Hara

Keiko Kurosawa

Atsushi Ichiyanagi

Yumiko Yamashita

Michiaki Yamashita

Yasutomo Shinohara

Kozo Hirokawa

Ryoko Tajima

Yasuko Araki

Taro Yoshimura

The purpose of the present invention is to provide a method for producing selenoneine that allows production of selenoneine at higher yields, even if an inorganic selenium compound is used as a selenium compound. This purpose can be achieved by a method for producing selenoneine, comprising the step of applying histidine and a selenium compound to a transformant to obtain selenoneine, wherein the transformant has at least one gene selected from the group consisting of a SatA gene, a CysB gene and a MetR gene, and an EgtA gene inserted therein and can overexpress the inserted genes.

Method for producing selenoneine

The purpose of the present invention is to provide a method for producing selenoneine that allows production of selenoneine at higher yields as compared with a conventional technology, and, therefore, enables selenoneine production on an industrial scale. This purpose can be achieved by a method for producing selenoneine, comprising the step of applying histidine and a selenium compound to a transformant that has a gene encoding an enzyme of (1) below introduced therein and that can overexpress the introduced gene, to obtain selenoneine. (1) An enzyme that catalyzes a reaction in which hercynylselenocysteine is produced from histidine and selenocysteine in the presence of S-adenosylmethionine and iron (II).

The purpose of the present invention is to provide an organism having an ergothioneine productivity that is capable of easily producing ergothioneine within a short period of time at a high yield, as compared with a conventional technology, and, therefore, enables ergothioneine production on an industrial scale. This purpose can be achieved by a transformed fungus into which a gene encoding enzyme (1) or genes encoding enzymes (1) and (2) have been inserted and in which the inserted gene(s) are overexpressed. (1) an enzyme catalyzing a reaction of synthesizing hercynyl cysteine sulfoxide from histidine and cysteine in the presence of S-adenosyl methionine, iron (II) and oxygen. (2) An enzyme catalyzing a reaction of synthesizing ergothioneine from hercynyl cysteine sulfoxide using pyridoxal 5'-phosphate as a coenzyme.

Transformed fungus having enhanced ergothioneine productivity and method for producing ergothioneine

The purpose of the present invention is to provide a method for producing selenoneine that allows production of selenoneine at higher yields as compared with a conventional technology, and, therefore, enables selenoneine production on an industrial scale. This purpose can be achieved by a method for producing selenoneine, comprising the step of applying histidine and a selenium compound to a transformant that has a gene encoding an enzyme of (1) below introduced therein and that can overexpress the introduced gene, to obtain selenoneine.

A flavin-binding glucose dehydrogenase having high substrate specificity for D-glucose and decreased reactivity to D-xylose and/or maltose. More specifically, a flavin-binding glucose dehydrogenase having one or more amino acid substitutions at a position corresponding to position 78, position 79, position 81, position 121, position 122, position 123, position 569 and position 612 of Mucor-derived flavin-binding glucose dehydrogenase. The flavin-binding glucose dehydrogenase enables D-glucose to be measured accurately without being susceptible to the effects of the presence of D-xylose and/or maltose, even under conditions of mounting a large amount of an enzyme such as in glucose sensors.

Flavin-binding glucose dehydrogenase having improved substrate specificity

A flavin-binding glucose dehydrogenase with a high substrate specificity for D-glucose. The flavin-binding glucose dehydrogenase which is derived from a microorganism belonging to the genus. The flavin-binding glucose dehydrogenase has a low reactivity for maltose, D-galactose and D-xylose compared to its reactivity for D-glucose, and therefore is relatively unaffected by these saccharide compounds. The flavin-binding glucose dehydrogenase is also relatively unaffected by dissolved oxygen, and allows accurate measurement of glucose amounts even in the presence of saccharide compounds other than glucose in samples.

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Noda, Japan

Keiichi Ichikawa