Artificial metalloenzymes based on protein assembly

Protein assembly: Controllable design strategies and applications in biology

“…[ 123–124 ] Protein nanostructures are expected to be assembled and disassembled by stimulation of the external environment; for example, ferritin shows a pH‐regulated encapsulation capacity, which forms into cages to encapsulate molecules such as drugs or enzymes under neutral conditions, while disassembles to release contents at pH = 2 or pH = 13. [ 125–126 ]…”

An artificial metallolyase with pliable 2-His-1-carboxylate facial triad for stereoselective Michael addition

“…Several methods, such as covalent, supramolecular anchoring, and cofactor substitution, have been established for the sitedirected anchoring of metal complexes to the protein cavity. [4][5][6][7][8][9][10] An alternative strategy involves the direct linking of bare metal ions with coordinating endogenous amino acids via dative covalent bonds. 11 This type of ArM is constructed by employing non-metalated natural or de novo proteins or by repurposing natural non-heme metalloenzymes, oen aided by computational design.…”

Cross-Linked Crystals of Dirhodium Tetraacetate/RNase A Adduct Can Be Used as Heterogeneous Catalysts

“…Indeed, it can tolerate the presence of high concentrations of organic compounds in aqueous solvents and thermal and pH variations. , Moreover, CLPCs overcome the limitation of both metal complexes and proteins alone. In fact, in CLPCs, the metal first, second, and third coordination spheres can be modulated by protein engineering, providing a catalyst with unprecedented performances, while the protein can retain its folding within the crystal lattice, even at extreme pH or in the presence of a high percentage of organic solvents. Hence, these systems can, in principle, improve the performances not only of the metal complexes but also of artificial metalloenzymes.…”

“…CLPCs are stable and insoluble in both organic and aqueous solvents and display good mechanical and thermal stability. , CLPCs are usually prepared using glutaraldehyde (GA) as the cross-linking agent because both monomeric and oligomeric GA species can interact with proteins, − making the cross-linking process nonspecific and thus useful for linking crystals of different proteins, regardless the nature of the protein or crystal packing . CLPCs have been used for several applications ranging from biosensing to drug delivery. − CLPCs are of great interest for the preparation of heterogeneous catalysts based on artificial metalloenzymes . In fact, when a protein crystal is stabilized by cross-linking, metal complexes can diffuse through solvent channels of the crystal lattice and interact with protein molecules, forming a stable metal/protein adduct crystal. , This system can be used as an effective heterogeneous catalyst because it allows one to screen better reaction conditions for catalysis.…”