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Atomically precise ~1‐nm Pt nanoparticles (nanoclusters, NCs) with ambient stability are important in fundamental research and exhibit diverse practical applications (catalysis, biomedicine, etc.). However, synthesizing such materials is challenging. Herein, by employing the mixture ligand protecting strategy, we successfully synthesized the largest organic‐ligand‐protected (~1‐nm) Pt23 NCs precisely characterized with mass spectrometry and single‐crystal X‐ray diffraction analyses. Interestingly, natural population analysis and Bader charge calculation indicate an alternate, varying charge ‐layer distribution in the sandwich‐like Pt23 NC kernel. Pt23 NCs can catalyze the oxygen reduction reaction under acidic conditions without requiring calcination and other treatments, and the resulting specific and mass activities without further treatment are sevenfold and eightfold higher than those observed for commercial Pt/C catalysts, respectively. Density functional theory and d‐band center calculations interpret the high activity. Furthermore, Pt23 NCs exhibit a photothermal conversion efficiency of 68.4 % under 532‐nm laser irradiation and can be used at least for six cycles, thus demonstrating great potential for practical applications. [ABSTRACT FROM AUTHOR]

Lattice tuning at the ≈1 nm scale is fascinating and challenging; for instance, lattice compression at such a minuscule scale has not been observed. The lattice compression might also bring about some unusual properties, which waits to be verified. Through ligand induction, we herein achieve the lattice compression in a ≈1 nm gold nanocluster for the first time, as detected by the single‐crystal X‐ray crystallography. In a freshly synthesized Au52(CHT)28 (CHT=S‐c−C6H11) nanocluster, the lattice distance of the (110) facet is found to be compressed from 4.51 to 3.58 Å at the near end. However, the lattice distances of the (111) and (100) facets show no change in different positions. The lattice‐compressed nanocluster exhibits superior electrocatalytic activity for the CO2 reduction reaction (CO2RR) compared to that exhibited by the same‐sized Au52(TBBT)32 (TBBT=4‐tert‐butyl‐benzenethiolate) nanocluster and larger Au nanocrystals without lattice variation, indicating that lattice tuning is an efficient method for tailoring the properties of metal nanoclusters. Further theoretical calculations explain the high CO2RR performance of the lattice‐compressed Au52(CHT)28 and provide a correlation between its structure and catalytic activity. [ABSTRACT FROM AUTHOR]

Ubiquitin (Ub)‐like protein ISG15 (interferon‐stimulated gene 15) regulates innate immunity and links with the evasion of host response by viruses such as SARS‐CoV‐2. Dissecting ISGylation pathways recently received increasing attention which can inform related disease interventions, but such studies necessitate the preparation and development of various ISG15 protein tools. Here, we find that the leader protease (Lbpro) encoded by foot‐and‐mouth disease virus can promote ligation reactions between recombinant ISG15 and synthetic glycyl compounds, generating protein tools such as ISG15‐propargylamide and ISG15‐rhodamine110, which are needed for cellular proteomic studies of deISGylases, and the screening and evaluation of inhibitors against SARS‐CoV‐2 papain‐like protease (PLpro). Furthermore, this strategy can be also used to load ISG15 onto the lysine of a synthetic peptide through an isopeptide bond, and prepare Ub and NEDD8 (ubiquitin‐like protein Nedd8) protein tools. [ABSTRACT FROM AUTHOR]

We present a method for atomically precise nanocluster synthesis. As an illustration, we introduced the reducing‐ligand induction combined method and synthesized a novel nanocluster, which was determined to be Au28(SCH2Ph‐tBu)22 with the same number of gold atoms as existing Au28(SR)20 nanoclusters but different ligands (hetero‐composition‐homo‐size). Compared with the latter, the former has distinct properties and structures. In particular, a novel kernel evolution pattern is reported, i.e. the quasi‐linear growth of Au4‐tetrahedron by sharing one vertex and structural features, including a tritetrahedron kernel with two bridging thiolates and two Au6(SCH2Ph‐tBu)6 hexamer chair‐like rings on the kernel surface were also first reported, which endow Au28(SCH2Ph‐tBu)22 with the best photoluminescence quantum yield among hydrophobic thiolated gold nanoclusters so far, probably due to the enhanced charge transfer from the bi‐ring to the kernel via Au−Au bonds. [ABSTRACT FROM AUTHOR]

Although face-centered cubic (fcc), body-centered cubic (bcc), hexagonal close-packed (hcp), and other structured gold nanoclusters have been reported, it was unclear whether gold nanoclusters with mix-packed (fcc and non-fcc) kernels exist, and the correlation between kernel packing and the properties of gold nanoclusters is unknown. A Au49(2,4-DMBT)27 nanocluster with a shell electron count of 22 has now been been synthesized and structurally resolved by single-crystal X-ray crystallography, which revealed that Au49(2,4-DMBT)27 contains a unique Au34 kernel consisting of one quasi-fcc-structured Au21 and one non-fcc-structured Au13 unit (where 2,4-DMBTH=2,4-dimethylbenzenethiol). Further experiments revealed that the kernel packing greatly influences the electrochemical gap (EG) and the fcc structure has a larger EG than the investigated non-fcc structure. [ABSTRACT FROM AUTHOR]

The identification of specific substrates of glutathione S-transferases (GSTs) is important for understanding drug metabolism. A method termed bioorthogonal identification of GST substrates (BIGS) was developed, in which a reduced glutathione (GSH) analogue was developed for recognition by a rationally engineered GST to label the substrates of the corresponding native GST. A K44G-W40A-R41A mutant (GST-KWR) of the mu-class glutathione S-transferases GSTM1 was shown to be active with a clickable GSH analogue (GSH-R1) as the cosubstrate. The GSH-R1 conjugation products can react with an azido-based biotin probe for ready enrichment and MS identification. Proof-of-principle studies were carried to detect the products of GSH-R1 conjugation to 1-chloro-2,4-dinitrobenzene (CDNB) and dopamine quinone. The BIGS technology was then used to identify GSTM1 substrates in the Chinese herbal medicine Ganmaocongji. [ABSTRACT FROM AUTHOR]

Ubiquitin (Ub)‐like protein ISG15 (interferon‐stimulated gene 15) regulates innate immunity and links with the evasion of host response by viruses such as SARS‐CoV‐2. Dissecting ISGylation pathways recently received increasing attention which can inform related disease interventions, but such studies necessitate the preparation and development of various ISG15 protein tools. Here, we find that the leader protease (Lbpro) encoded by foot‐and‐mouth disease virus can promote ligation reactions between recombinant ISG15 and synthetic glycyl compounds, generating protein tools such as ISG15‐propargylamide and ISG15‐rhodamine110, which are needed for cellular proteomic studies of deISGylases, and the screening and evaluation of inhibitors against SARS‐CoV‐2 papain‐like protease (PLpro). Furthermore, this strategy can be also used to load ISG15 onto the lysine of a synthetic peptide through an isopeptide bond, and prepare Ub and NEDD8 (ubiquitin‐like protein Nedd8) protein tools. [ABSTRACT FROM AUTHOR]

We present a method for atomically precise nanocluster synthesis. As an illustration, we introduced the reducing‐ligand induction combined method and synthesized a novel nanocluster, which was determined to be Au28(SCH2Ph‐tBu)22 with the same number of gold atoms as existing Au28(SR)20 nanoclusters but different ligands (hetero‐composition‐homo‐size). Compared with the latter, the former has distinct properties and structures. In particular, a novel kernel evolution pattern is reported, i.e., the quasi‐linear growth of Au4‐tetrahedron by sharing one vertex and structural features, including a tritetrahedron kernel with two bridging thiolates and two Au6(SCH2Ph‐tBu)6 hexamer chair‐like rings on the kernel surface were also first reported, which endow Au28(SCH2Ph‐tBu)22 with the best photoluminescence quantum yield among hydrophobic thiolated gold nanoclusters so far, probably due to the enhanced charge transfer from the bi‐ring to the kernel via Au−Au bonds. [ABSTRACT FROM AUTHOR]