Modulating Electron Transfer in Vanadium‐Based Artificial Enzymes for Enhanced ROS‐Catalysis and Disinfection

Abstract

The dramatically increasing demands in enzyme-like catalytic biosynthesis and biotherapeutics have promoted thrilling innovations to engineer artificial enzymes (AEs), [1][2][3][4][5][6][7][8] especially the haloperoxidase (HPO)-like AEs that can generate potent reactive oxygen species (ROS), [9][10][11][12] including • OH, • O 2 -, and HClO/HBrO, for antibacterial and antitumor applications. [13][14][15][16][17][18][19][20][21] Despite the fast flourishment of HPO-like AEs, further enhancing their biocatalytic performances is still a confusing black box since their electronic structures of metal centers and ROScatalytic mechanisms remain largely unclear. [22] The grand challenge is to develop new ideas and precise theoretical guidance for the de novo design of HPOlike AEs and clarify the corresponding electronic structures and catalytic behaviors of metal centers. [23,24] In particular, the vanadium oxide (V 2 O 5 ) is one of the most representative nanomaterials that displays HPO-like activities, which shows broad application potentials from killing pathogenic cells to preventing marine biofouling by catalyzing H 2 O 2 to potent ROS. Compared to natural HPO, the V 2 O 5 -based AEs provide a costeffective, stable, and broad reaction condition pathway. However, the currently reported strategies, [25,26] such as size tuning, modification of composition, and crystal facets engineering, present limited effects on further enhancing the biocatalytic performances of V 2 O 5 -based AEs. Pathways that can efficiently augment the intrinsic ROS-catalytic activities of metal centers in V 2 O 5 -based AEs are still missing.In V 2 O 5 -based AEs, the V centers possess depressed d electrons density due to its coordination with neighboring electronegative oxygen atoms, [27,28] which causes the V-d 2 z electrons (this d 2 z orbital is perpendicular to the basal plane) to become more accessible to form head-on-head sigma bonds with O-p z orbital. Therefore, the V centers in V 2 O 5 possess strong interaction with H 2 O 2 and suppressed dissociation of oxygenintermediates, [25] consequently resulting in reduced reaction dynamics. The de novo design of the d electrons of V centers to modulate the adsorption-energy between the H 2 O 2 and metal sites is essential for further enhancing their intrinsic ROS-catalytic activities. [29] One approach to weaken the accessibility of d 2 z electrons of metal centers is the filling of d yz orbitals near Nanomaterials-based artificial enzymes (AEs) have flourished for more than a decade. However, it is still challenging to further enhance their biocatalytic performances due to the limited strategies to tune the electronic structures of active centers. Here, a new path is reported for the de novo design of the d electrons of active centers by modulating the electron transfer in vanadium-based AEs (VO x -AE) via a unique Zn-O-V bridge for efficient reactive oxygen species (ROS)-catalysis. Benefiting from the electron transfer from Zn to V, the V site in VO x -AE exhibits a lower valence state tha...

Catalase‐Mimetic Artificial Biocatalysts with Ru Catalytic Centers for ROS Elimination and Stem‐Cell Protection

“…species, electronic states, and coordination modes could provide new opportunities to develop efficient catalysts for diverse chemical/biochemical reactions. [23][24][25][26][27][28] Evolution has produced enzymes incorporating transition metals, including Fe, Co, Mn, etc. Ru is a member of the iron group elements that shows low electronegativity and high metallic electronic structure.…”

What are inorganic nanozymes? Artificial or inorganic enzymes

“…274–277 Scientists can gain inspiration from the metal architectures in the nanoparticles to design artificial biocatalysts or functionalized nanomaterials that are more stable, efficient, and specific. 222,223,278–285…”

Rapid synthesis of bismuth-organic frameworks as selective antimicrobial materials against microbial biofilms

“…It is highly urgent to develop alternative antimicrobial strategies and approaches to tackling this serious issue. Recently, both organic- and inorganic-based materials have been increasingly used to combat the crisis, such as molybdenum disulfide for releasing near-infrared light-induced nitric oxide and cobalt-doped nickel oxide nanoparticles for enhancing the catalytic effects of reactive oxygen species on bacterial biofilms [ [2] , [3] , [4] , [5] , [6] , [7] , [8] , [9] , [10] , [11] ]. It is noteworthy that bismuth as a relatively environmental-friendly heavy metal has been used for catalysis, energy storage and biomedicines [ [12] , [13] , [14] , [15] ].…”