Compositions are disclosed herein comprising dextran that comprises (i) 87-93 wt % glucose linked at positions 1 and 6; (ii) 0.1-1.2 wt % glucose linked at positions 1 and 3; (iii) 0.1-0.7 wt % glucose linked at positions 1 and 4; (iv) 7.7-8.6 wt % glucose linked at positions 1, 3 and 6; and (v) about 0.4-1.7 wt % glucose linked at (a) positions 1, 2 and 6, or (b) positions 1, 4 and 6. Aqueous forms of this composition have enhanced viscosity profiles. Further disclosed are methods of using compositions comprising dextran, such as increasing the viscosity of an aqueous composition. Enzymatic reactions for producing dextran are also disclosed.

An enzymatically produced soluble ?-glucan fiber composition is provided suitable for use as a digestion resistant fiber in food and feed applications. The soluble ?-glucan fiber composition can be blended with one or more additional food ingredients to produce fiber-containing compositions. Methods for the production and use of compositions comprising the soluble ?-glucan fiber are also provided.

An enzymatically produced soluble ?-glucan fiber composition is provided suitable for use as a digestion resistant fiber in food and feed applications. The soluble ?-glucan fiber composition can be blended with one or more additional food ingredients to produce fiber-containing compositions. Methods for the production and use of compositions comprising the soluble ?-glucan fiber are also provided.

Compositions are disclosed herein comprising dextran that comprises (i) 87-93 wt % glucose linked at positions 1 and 6; (ii) 0.1-1.2 wt % glucose linked at positions 1 and 3; (iii) 0.1-0.7 wt % glucose linked at positions 1 and 4; (iv) 7.7-8.6 wt % glucose linked at positions 1, 3 and 6; and (v) about 0.4-1.7 wt % glucose linked at (a) positions 1, 2 and 6, or (b) positions 1, 4 and 6. Aqueous forms of this composition have enhanced viscosity profiles. Further disclosed are methods of using compositions comprising dextran, such as increasing the viscosity of an aqueous composition. Enzymatic reactions for producing dextran are also disclosed.

Compositions are disclosed herein comprising dextran that comprises (i) 87-93 wt % glucose linked at positions 1 and 6; (ii) 0.1-1.2 wt % glucose linked at positions 1 and 3; (iii) 0.1-0.7 wt % glucose linked at positions 1 and 4; (iv) 7.7-8.6 wt % glucose linked at positions 1, 3 and 6; and (v) about 0.4-1.7 wt % glucose linked at (a) positions 1, 2 and 6, or (b) positions 1, 4 and 6. Aqueous forms of this composition have enhanced viscosity profiles. Further disclosed are methods of using compositions comprising dextran, such as increasing the viscosity of an aqueous composition. Enzymatic reactions for producing dextran are also disclosed.

Compositions are disclosed herein comprising at least one dextran ether compound that comprises uncharged, anionic, and/or cationic organic groups. The degree of substitution of one or more dextran ether compounds is about 0.0025 to about 3.0. Dextran from which the disclosed ether compounds can be derived can have a weight-average molecular weight of about 50-200 million Daltons and/or a z-average radius of gyration of about 200-280 nm. Also disclosed are methods of producing dextran ether compounds, as well as methods of using these ether compounds in various applications.

Compositions are disclosed herein comprising at least one dextran ether compound that comprises uncharged, anionic, and/or cationic organic groups. The degree of substitution of one or more dextran ether compounds is about 0.0025 to about 3.0. Dextran from which the disclosed ether compounds can be derived can have a weight-average molecular weight of about 50-200 million Daltons and/or a z-average radius of gyration of about 200-280 nm. Also disclosed are methods of producing dextran ether compounds, as well as methods of using these ether compounds in various applications.

The present invention relates to a recombinant process for the production of truncated or mutated dextransucrases while conserving the enzymatic activity or their specificity in the synthesis of the ?-1,6 bonds. The present invention relates to nucleic acid sequences of truncated or mutated dextransucrases, vectors containing the nucleic acid sequences and host cells transformed by sequences encoding truncated or mutated dextransucrases. In another aspect, the invention concerns a method for producing, in a recombinant manner, truncated or mutated dextransucrases which conserve their enzymatic activity or which conserve their specificity in the synthesis of ?-1,6 bonds and can produce, from saccharose, dextrans with high molar mass and modified rheological properties compared with the properties of dextran obtained with the native enzyme and isomalto-oligosaccharides with a controlled molar mass and dextrans. The dextrans and isomalto-oligosaccharides of the invention can be used namely as texturing agents or as prebiotics.

The present invention relates to a recombinant process for the production of truncated or mutated dextransucrases while conserving the enzymatic activity or their specificity in the synthesis of the ?-1,6 bonds. The present invention relates to nucleic acid sequences of truncated or mutated dextransucrases, vectors containing the nucleic acid sequences and host cells transformed by sequences encoding truncated or mutated dextransucrases. In another aspect, the invention concerns a method for producing, in a recombinant manner, truncated or mutated dextransucrases which conserve their enzymatic activity or which conserve their specificity in the synthesis of ?-1,6 bonds and can produce, from saccharose, dextrans with high molar mass and modified rheological properties compared with the properties of dextran obtained with the native enzyme and isomalto-oligosaccharides with a controlled molar mass and dextrans. The dextrans and isomalto-oligosaccharides of the invention can be used namely as texturing agents or as prebiotics.

Polypeptides having the ability to specifically form connections of glucosyl units in alpha 1,3 on an acceptor having at least one hydroxyl moiety are presented. The polypeptides include i) the pattern I of sequence SEQ ID NO: 1, ii) the pattern II of sequence SEQ ID NO: 2, iii) the pattern III of sequence SEQ ID NO: 3, and iv) the pattern IV of sequence SEQ ID NO: 4, or derivates from one or several of said patterns, wherein the polypeptide furthermore has an aspartic residue (D) at position 5 of the pattern II (SEQ ID NO: 2), a glutamic acid residue (E) at position 6 of the pattern III (SEQ ID NO: 3) and an aspartic acid residue (D) at position 6 of the pattern IV (SEQ ID NO: 4). Methods for producing acceptors connected to glucosyl units in alpha 1,3 using the polypeptides are also provided.