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.

Novel hydrogels that can serve as 3D hypoxic microenvironments are disclosed. Oxygen controllable, hypoxia-inducible hydrogels (HI hydrogels) are composed of a phenolic agent and polymer backbone, which can form hydrogel networks via oxygen consumption in an enzyme-mediated crosslinking reaction. The HI hydrogels are degradable, cytocompatible, and have tunable mechanical properties. Oxygen levels and gradients within the HI hydrogels are controlled and precisely predicted. As a result, the HI hydrogels induce prolonged hypoxic conditions. The HI hydrogels guide vascular morphogenesis in vitro by activating hypoxia-inducible factors and promote neovascularization from tissue, as well as stimulate tissue in dynamic in vivo environments. The HI hydrogels are a new class of biomaterials that are useful in many applications, ranging from the engineering of de novo tissues and disease models to the treatment of vascular disorders.

Novel hydrogels that can serve as 3D hypoxic microenvironments are disclosed. Oxygen controllable, hypoxia-inducible hydrogels (HI hydrogels) are composed of a phenolic agent and polymer backbone, which can form hydrogel networks via oxygen consumption in an enzyme-mediated crosslinking reaction. The HI hydrogels are degradable, cytocompatible, and have tunable mechanical properties. Oxygen levels and gradients within the HI hydrogels are controlled and precisely predicted. As a result, the HI hydrogels induce prolonged hypoxic conditions. The HI hydrogels guide vascular morphogenesis in vitro by activating hypoxia-inducible factors and promote neovascularization from tissue, as well as stimulate tissue in dynamic in vivo environments. The HI hydrogels are a new class of biomaterials that are useful in many applications, ranging from the engineering of de novo tissues and disease models to the treatment of vascular disorders.

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 a graft copolymer that comprises: (i) a backbone comprising dextran that has been modified with about 1%-25% alpha-1,2 branches, and (ii) one or more alpha-1,3-glucan side chains comprising at least about 50% alpha-1,3 glycosidic linkages. Further disclosed are reactions for producing such graft copolymers, as well as their use in derivatives, films and various other applications.

Compositions are disclosed herein comprising a graft copolymer that comprises: (i) a backbone comprising dextran that has been modified with about 1%-25% alpha-1,2 branches, and (ii) one or more alpha-1,3-glucan side chains comprising at least about 50% alpha-1,3 glycosidic linkages. Further disclosed are reactions for producing such graft copolymers, as well as their use in derivatives, films and various other applications.

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.