0000000000366009
AUTHOR
David Talens-perales
Revalorization of cellulosic wastes from Posidonia oceanica and Arundo donax as catalytic materials based on affinity immobilization of an engineered β-galactosidase
Catalytic materials obtained by enzyme immobilization have multiple potential applications in the food industry. The choice of the immobilization method and support may be critical to define the properties of the immobilized enzyme compared to the soluble form. Although the use of immobilized enzymes shows multiple advantages, their catalytic efficiency is compromised in many instances. Molecular engineering techniques have been used to generate hybrid proteins where the enzyme of interest is fused to a module with affinity to a specific biopolymer. Binding of the hybrid TmLac-CBM2 protein, in which the β-galactosidase from Thermotoga maritima is fused to a carbohydrate-binding module from …
Matryoshka enzyme encapsulation: Development of zymoactive hydrogel particles with efficient lactose hydrolysis capability.
This report describes an efficient procedure for enzyme encapsulation and its application for the hydrolysis of lactose. The enzymatic material that has been developed consists of hydrogel particles (ca. 3–4 mm of diameter) composed of either alginate or an alginate-agarose combination, in which bacterial cells loaded with a thermostable β-galactosidase are embedded. The cells were rendered fully permeable to the substrate, either chromogenic p-nitrophenyl galactose or lactose, by thermal treatment at 75 °C. Hydrogel particles made of a mixture of alginate and agarose displayed high catalytic activity (i.e. 1 g of beads hydrolyze the lactose equivalent of 100 mL of milk in 15 min) and therm…
Development of enzymatically-active bacterial cellulose membranes through stable immobilization of an engineered beta-galactosidase
Enzymatically-active bacterial cellulose (BC) was prepared by non-covalent immobilization of a hybrid enzyme composed by a β-galactosidase from Thermotoga maritima (TmLac) and a carbohydrate binding module (CBM2) from Pyrococcus furiosus. TmLac-CBM2 protein was bound to BC, with higher affinity at pH 6.5 than at pH 8.5 and with high specificity compared to the non-engineered enzyme. Both hydrated (HBC) and freeze-dried (DBC) bacterial cellulose showed equivalent enzyme binding efficiencies. Initial reaction rate of HBC-bound enzyme was higher than DBC-bound and both of them were lower than the free enzyme. However, enzyme performance was similar in all three cases for the hydrolysis of 5% l…