Ajinomoto Co., Ltd.

Ei-ichiro Suzuki

Tatsuki Kashiwagi

Kunihiko Watanabe

Masakazu Sugiyama

Kohki Ishikawa

Nobuhisa Shimba

Hiroshi Takagi

Mikhail Markovich Gusyatiner

Osamu Kurahashi

Yasuhisa Asano

Keiichi Yokoyama

Yasuhiro Mihara

Hisashi Kawasaki

Megumi Shimaoka

Kazuo Hirayama

Mikhail Kharisovich Ziyatdinov

Keiko Gondoh

Tohru Kouda

Yuko Kai

Ekaterina Igorevna Redkina

Rie Kozutsumi

A D-aminotransferase can be modified so as to efficiently produce (2R,4R)-monatin having high sweetness intensity from 4-(indol-3-ylmethyl)-4-hydroxy-2-oxoglutaric acid by mutating the amino acid sequence of a wild-type D-aminotransferase represented in SEQ ID NO:4.

Mutated D-aminotransferase and method for producing optically active glutamic acid derivatives using the same

A D-aminotransferase can be modified so as to efficiently produce (2R,4R)-monatin having high sweetness intensity from 4-(indol-3-ylmethyl)-4-hydroxy-2-oxoglutaric acid by substituting an amino acid at least at one of positions (positions 100, 180 to 183, 243 and 244) involved in efficiently producing the (2R,4R)-monatin in an amino acid sequence of a wild-type D-aminotransferase represented in SEQ ID NO:2.

The present invention relates to a method for designing and preparing mutant transglutaminases on the basis of the three-dimensional structure of MTG derived from(MTG), and the mutant MTG thus prepared. The present invention provides a method for modifying MTG on the basis of the three-dimensional structure, and transglutaminase having reactivity on the substrate improved by the method. In the present invention, the binding site of MTG for the substrate is extrapolated based on the three-dimensional structure obtained by X-ray crystal structure analysis of MTG crystals, and the mutant transglutaminases are designed and produced by replacing, inserting or deleting amino acid residues positioned at the substrate-binding site of the transglutaminase.

Polynucleotide encoding a mutant transglutaminase

A D-aminotransferase can be modified so as to efficiently produce (2R, 4R)-monatin having high sweetness intensity from 4-(indol-3-ylmethyl)-4-hydroxy-2-oxoglutaric acid by substituting an amino acid at least at one of positions (positions 100, 180 to 183, 243 and 244) involved in efficiently producing the (2R, 4R)-monatin in an amino acid sequence of a wild-type D-aminotransferase represented in SEQ ID NO:2.

O-acetylserine, L-cysteine and sulphurous compounds derived therefrom may be produced using a bacterium belonging to the genuswhich harbors a mutant feedback-resistant serine acetyltransferases in which the amino acid sequence corresponding to positions from 89 to 96 in a wild-type serine acetyltransferase is replaced with any one of the amino acid sequences shown in SEQ ID NOS: 4 to 9, and feedback inhibition by L-cysteine in the bacterium is desensitized.

Mutant serine acetyltransferase

There is provided a mutant nucleoside-5'-phosphate producing enzyme with improved nucleoside-5&#x2032;-phosphate producing ability of a nucleoside-5&#x2032;-phosphate producing enzyme that has transphosphorylation activity and/or phosphatase activity and has one Lys residue, two Arg residues and two His residues with distances between their C&#x3b1;'s within a particular ranges and a space around them allowing a binding of a nucleoside, of which mutation is designed by using the crystal structure of EB-AP.

Variant nucleoside-5'-phosphate producing enzyme

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Kawasaki, Japan

Ei-ichiro Suzuki