Gene expression cassette and a transformant, and a method for manufacturing 2-deoxy-scyllo-inosose and a method for purifying 2-deoxy-scyllo-inosose using said transformant

Abstract

A transformant is prepared to insert at least a gene expression cassette comprising a gene involved in the synthesis of 2-deoxy-scyllo-inosose into E. coli as host cells. A 2-deoxy-scyllo-inosose is synthesized from D-glucose, oligosaccharide, polysaccharide, starch and rice bran, using the transformant. A culture solution containing the 2-deoxy-scyllo-inosose is treated with a mixed bed or double bed type column comprising a hydrogen form of strong acidic cation exchange resin and an organic ion form of basic anion exchange resin. The 2-deoxy-scyllo-inosose as purified is reacted with trimethoxymethane to convert into 2-deoxy-scyllo-inosose dimethylketal, and the dimethylketal is crystallized and purified. Then, DOI is highly purified through hydrolyzing the dimethylketal in the presence of acid.

1 .- 14 . (canceled) 
     
     
         15 . A method for manufacturing 2-deoxy-scyllo-inosose, the method comprising:
 contacting an isolated host cell with carbon source, wherein the host cell comprises a gene expression cassette having a gene encoding 2-deoxy-scyllo-inosose synthase with at least one disrupted gene selected from the group consisting of pgi gene encoding phosphoglucose isomerase, zwf gene encoding glucose-6-phosphate 1-dehydrogenase, pgm gene encoding phosphoglucomutase, and rmf gene encoding ribosome modulation factor involved in modification of protein synthesis during stationary phase, and wherein the host cell is  Escherichia coli , and 2-deoxy-scyllo-inosose is synthesized within the host cell.   
     
     
         16 . The method for manufacturing 2-deoxy-scyllo-inosose according to  claim 15 , wherein said carbon source is at least one type of carbon sources selected from the group consisting of D-glucose, oligosaccharide, polysaccharide, starch, cellulose, rice bran and molasses and biomasses capable of obtaining D-glucose. 
     
     
         17 . A composition comprising 2-deoxy-scyllo-inosose obtained from the method for manufacturing 2-deoxy-scyllo-inosose according to  claim 15 . 
     
     
         18 . A method for purifying 2-deoxy-scyllo-inosose, the method comprising:
 contacting an isolated host cell with a carbon source to obtain a composition containing 2-deoxy-scyllo-inosose, wherein the host cell comprises a gene expression cassette having a gene encoding 2-deoxy-scyllo-inosose synthase with at least one disrupted gene selected from the group consisting of pgi gene encoding phosphoglucose isomerase, zwf gene encoding glucose-6-phosphate 1-dehydrogenase, pgm gene encoding phosphoglucomutase, and rmf gene encoding ribosome modulation factor involved in modification of protein synthesis during stationary phase, and wherein the host cell is  Escherichia coli , and 2-deoxy-scyllo-inosose is synthesized within the host cell; and   treating said composition with mixed bed column or double bed column comprising a hydrogen ion form of a strong-acid cation exchange resin and an organic acid ion form of a basic anion exchange resin.   
     
     
         19 . The method for purifying 2-deoxy-scyllo-inosose according to  claim 18 , wherein said organic acid ion form of the basic anion exchange resin is acetate ion form of anion exchange resin. 
     
     
         20 . A composition of 2-deoxy-scyllo-inosose obtained from the method for purifying 2-deoxy-scyllo-inosose according to  claim 18 . 
     
     
         21 . A method for purifying 2-deoxy-scyllo-inosose according to  claim 18 , further comprising:
 reacting the composition comprising 2-deoxy-scyllo-inosose with trialkoxymethanes to obtain 2-deoxy-scyllo-inosose dialkylketals; and   hydrolyzing said 2-deoxy-scyllo-inosose dialkylketals in the presence of acid.   
     
     
         22 . The method for purifying 2-deoxy-scyllo-inosose according to  claim 21 , wherein said trialkoxymethanes are trimethoxymethane. 
     
     
         23 . A composition comprising 2-deoxy-scyllo-inosose obtained from the method for purifying 2-deoxy-scyllo-inosose according to  claim 22 .