Enzymes covalently immobilized on highly porous materials are demonstrated to have very high biocatalytic activity and good recyclability, exemplified by Candida antarctica Lipase B (CAL‐B). Polymerized high internal phase emulsions (PolyHIPEs, see figure) are developed for covalent grafting of proteins (enzymes) via the reaction of the protein surface lysine residues with active ester moieties in the monolithic material.

Virus particles are probably the most precisely defined nanometre-sized objects that can be formed by protein self-assembly. Although their natural function is the storage and transport of genetic material, they have more recently been applied as scaffolds for mineralization and as containers for the encapsulation of inorganic compounds. The reproductive power of viruses has been used to develop versatile analytical methods, such as phage display, for the selection and identification of (bio)active compounds. To date, the combined use of self-assembly and reproduction has not been used for the construction of catalytic systems. Here we describe a self-assembled system based on a plant virus that has its coat protein genetically modified to provide it with a lipase enzyme. Using single-object and bulk catalytic studies, we prove that the virus-anchored lipase molecules are catalytically active. This anchored biocatalyst, unlike man-made supported catalysts, has the capability to reproduce itself in vivo, generating many independent catalytically active copies.

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We show herein that electrochemical atomic force microscopy (AFM-SECM), operated in molecule touching (Mt) mode and combined with redox immunomarking, enables the in situ mapping of the distribution of proteins on individual virus particles and makes localization of individual viral proteins possible. Acquisition of a topography image allows isolated virus particles to be identified and structurally characterized, while simultaneous acquisition of a current image allows the sought after protein, marked by redox antibodies, to be selectively located. We concomitantly show that Mt/AFM-SECM, due to its single-particle resolution, can also uniquely reveal the way redox functionalization endowed to viral particles is distributed both statistically among the viruses and spatially over individual virus particles. This possibility makes Mt/AFM-SECM a unique tool for viral nanotechnology.

Here we develop a novel approach allowing the noncovalent assembly of proteins on well-defined nanoscaffolds such as virus particles. The antibody-binding peptide Z33 was genetically fused to the monomeric yellow fluorescent protein and 4-coumarate:CoA-ligase 2. This Z33 "tag" allowed their patterning on the surface of zucchini yellow mosaic virus by means of specific antibodies directed against the coat protein of the virus. The approach was validated by affinity assays and correlative microscopy. The coverage efficiency was ≈ 87%. Fluorescence and enzymatic activity were fully retained after assembly. The principle of using the combination of a scaffold-specific antibody and Z33-fusion proteins can be extended to a wide variety of proteins/enzymes and antigenic scaffolds to support coupling for creating functional "biochips" with optical or catalytic properties.