The enzyme-mediated autodeposition of casein: effect of enzyme immobilization on deposition of protein structures

Abstract

The enzyme-mediated autodeposition on the example of casein is reviewed, and deposition of casein structures is investigated in relation to applied immobilization methods of enzyme. First, casein is described in detail with respect to its structure in aqueous environments, followed by presentation of historical and current nonfood applications of casein. The presented process uses enzymes to trigger deposition of bio-based particles in close proximity to a support surface and allows for a high control over film formation and site-specificity. This is ensured by immobilization of enzyme on the support material. The herein described system is based on casein as protein and chymosin as enzyme. Different immobilization methods are investigated with respect to obtainable casein coatings, layers, and structures. Physical adsorption of enzyme enables the formation of casein coatings with controllable film thickness and is suitable for in situ buildup of adhesive layers due to diffusion of enzyme. The highest control over film formation is provided by covalent attachment of enzyme. Based on the attained results, the enzymemediated autodeposition gives new insights into biological material design. Graphical abstractEnzyme Casein micelle intact Bulk zone (no enzyme) Reaction zone Phe Met Support Support Casein micelle cleaved

Site-Specific Addressing of Particles and Coatings via Enzyme-Mediated Destabilization

“…The inner part of the reactive circle also shows deposition of polymer, in contrast to the outside area which is almost free of any particles. The important feature of site-specificity, observed in all previous varieties of EMA, can thus be confirmed for the herein presented approach as well [8,12,16,17].…”

“…This renders them unsuitable for many industrial applications.To overcome this, we previously introduced a novel technology which adapts the architectural skills of enzymes and enables defined deposition of colloidal particles in both a highly specific and easy-to-apply manner: the enzyme mediated addressing (EMA) [7]. Herein, enzymes control the destabilization or synthesis of the desired particles in close proximity to a support surface.Deposition of those particles takes place only within the area of enzymatic activity; it is therefore site-specific [8]. The area of deposition is predefined by the selected method of enzyme immobilization.…”

“…Deposition of those particles takes place only within the area of enzymatic activity; it is therefore site-specific [8]. The area of deposition is predefined by the selected method of enzyme immobilization.…”

Physical Quality and Microstructure of Casein-Sodium Tripholyphosphate Edible Film Making

“…The thickness of the edible film in a formula is influenced by the print media used and the volume of the solution poured into the media. The thickness of the edible film in a formula shows differences or unevenness [21] and [22] stated that the thickness of the edible film can be controlled by reaction parameters such as pH value, settling time and casein concentration. The addition of casein formulations in small amounts can cause the thickness of the edible film forming solution is constant, thus affecting the composition and interactions between components.…”

Putting precision and elegance in enzyme immobilisation with bio-orthogonal chemistry

“…[45][46][47] For example a poly-His-tagged glutaryl acylase, an ab-heterodimeric enzyme of significant industrial interest, was immobilised on such a support. 48 The highest selectivity in specific immobilisation was achieved by using low-density chelate groups and metals with a low affinity (e.g. Co) (Fig.…”