The present invention relates to a method for converting at least one oligo- and/or polysaccharide into fructose comprising the steps of: a) adding to a composition comprising water, phosphate and at least one oligo- and/or polysaccharide at least four enzymes, and b) subsequently enzymatically converting the at least one oligo- and/or polysaccharide to fructose in the presence of the at least four enzymes, wherein in step a) at least one additional saccharide is added, whereby the at least one additional saccharide is selected from the group consisting of saccharides comprising 20 or less monosaccharide residues and/or combinations thereof; wherein in step a) the at least four enzymes, preferably at least five enzymes, are selected from the group consisting of transferases, phosphorylases, mutases, isomerases, hydrolases, phosphatases and combinations thereof; and wherein at least one enzyme in step a) is a phosphatase.

Production of fructose from saccliarides by processes, in which fructose 6-phosphate phosphatase (F6PP) catalyzes the conversion of fructose 6-phosphate (F6P) to a fructose, in the presence of one or more divalent cations, Mg.sup.2+, Zn.sup.2+, Ca.sup.2+, Co.sup.2+, and Mn.sup.2+, are disclosed herein.

Provided herein, in some embodiments, are systems, methods, and compositions (e.g., cells and cell lysates) for enzymatically converting a polymeric glucose carbohydrate (e.g., starch) to sugar.

The invention relates to immobilized enzyme compositions for the preparation of a hexose. Hexoses include, for example, tagatose, psicose, fructose, allose, mannose, galactose, altrose, talose, sorbose, gulose, idose, and inositol. The invention also relates to an enzymatic process for preparing a hexose from a saccharide by contacting a starch derivative with an immobilized enzyme composition of the invention.

Disclosed is a new tagatose 6-phosphate 4-epimerase, which is capable of converting fructose 6-phosphate into tagatose 6-phosphate and vice versa. Also disclosed is an application of the enzyme in tagatose production.

Disclosed is a new tagatose 6-phosphate 4-epimerase, which is capable of converting fructose 6-phosphate into tagatose 6-phosphate and vice versa. Also disclosed is an application of the enzyme in tagatose production.

Provided herein, in some embodiments, are systems, methods, and compositions (e.g., cells and cell lysates) for enzymatically converting a polymeric glucose carbohydrate (e.g., starch) to sugar.

Provided herein, in some embodiments, are systems, methods, and compositions (e.g., cells and cell lysates) for enzymatically converting a polymeric glucose carbohydrate (e.g., starch) to sugar.

Provided herein, in some embodiments, are systems, methods, and compositions (e.g., cells and cell lysates) for enzymatically converting a polymeric glucose carbohydrate (e.g., starch) to sugar.

Provided are a recombinant microorganism modified by means of genetic engineering and an application of the recombinant microorganism in production of tagatose, a preparation method for the recombinant microorganism, a tagatose production strain and a tagatose production method. According to the recombinant microorganism, the tagatose is produced by taking glucose as a substrate or taking glycerol and glucose as substrates; the efficiency of conversion and production of tagatose by means of the recombinant microorganism is high, and a multi-enzyme purification process step is not needed.