Isolation, characterization, and circulation sphere of a filovirus in fruit bats.

Bats are associated with the circulation of most mammalian filoviruses (FiVs), with pathogenic ones frequently causing deadly hemorrhagic fevers in Africa. Divergent FiVs have been uncovered in Chinese bats, raising concerns about their threat to public health. Here, we describe a long-term surveillance to track bat FiVs at orchards, eventually resulting in the identification and isolation of a FiV, Dehong virus (DEHV), from Rousettus leschenaultii bats. DEHV has a typical filovirus-like morphology with a wide spectrum of cell tropism. Its entry into cells depends on the engagement of Niemann-Pick C1, and its replication is inhibited by remdesivir. DEHV has the largest genome size of filoviruses, with phylogenetic analysis placing it between the genera Dianlovirus and Orthomarburgvirus, suggesting its classification as the prototype of a new genus within the family Filoviridae. The continuous detection of viral RNA in the serological survey, together with the wide host distribution, has revealed that the region covering southern Yunnan, China, and bordering areas is a natural circulation sphere for bat FiVs. These emphasize the need for a better understanding of the pathogenicity and potential risk of FiVs in the region.

Structural and Chemical Bonding Properties of AuS2H0/-: A Photoelectron Velocity-Map Imaging Spectroscopic and Theoretical Study.

Mass-selected photoelectron velocity-map imaging spectroscopy was employed to investigate the geometrical and electronic properties of AuS2H-/0. The comprehensive comparison between the experiment and theoretical calculations establishes that the ground-state AuS2H- anion has a mixed-ligand structure [SAuSH]- with an unsymmetrical S-Au-S unit. Further chemical bonding analyses on AuS2H and comparison with the isoelectronic AuS2- suggest that the unique S-Au-S unit in these species features two three-center, three-electron π-bonding, and one three-center, two-electron σ-bonding. The isoelectronic replacement of the extra electron in AuS2- by the H atom can lead to σ bonding evolution from the electron-sharing bond to the dative bond. These findings are conducive to the fundamental understanding of the intrinsic stability of thiolate-protected gold nanoclusters and their delicate ligand design to achieve desirable properties.

Cocrystallization-driven Formation of fcc-based Ag110 Nanocluster with Chinese Triple Luban Lock Shape.

Luban locks with mortise and tenon structure have structural diversity and architectural stability, and it is extremely challenging to synthesize Luban lock-like structures at the molecular level. In this work, we report the cocrystallization of two structurally related atom-precise fcc silver nanoclusters Ag110 (SPhF)48 (PPh3 )12 (Ag110 ) and Ag14 (µ6 -S)(SPhF)12 (PPh3 )8 (Ag14 ). It is worth noting that the Ag110 cluster is the first compound to simulate the complex Luban lock structure at the molecular level. Meanwhile, Ag110 is the largest known fcc-based silver nanocluster, so far, there is no precedent for fcc silver nanocluster with more than 100 silver atoms. DFT calculations show that Ag110 is a 58-electron superatom with an electronically closed shell1S2 1P6 1D10 2S2 1F14 2P6 1G18 . Ag110 ⋅Ag14 can rapidly catalyze the reduction of 4-nitrophenol within 4 minutes. In addition, Ag110 presents clear structural evidence to reveal the critical size and mechanism of the transformation of metal core from fcc stacking to quasi-spherical superatom. This research work provides an important structural model for studying the nucleation mechanism and structural assembly of silver nanoclusters.

Coordination-induced bond weakening in NiC3: An experimental and theoretical investigation.

Mass-selected photoelectron velocity-map imaging spectroscopy in conjunction with the density functional theory calculations was employed to investigate the geometrical and chemical bonding properties of NiC3-/0. Both the photoelectron spectrum and photoelectron angular distribution were measured from the spectra, yielding useful geometrical and electronic information about NiC3-/0. The complementary theoretical calculations suggest that the linear and fan-like structures were both populated experimentally in the cluster beam. Further comparative study on the synergistic donor-acceptor interactions in both isomers revealed the side-on coordination-induced bond weakening in the fan-like isomer as compared to the linear isomer. These findings will shed light on the structure-dependent reactivity of transition metal carbides.

Health Status Recognition Method for Rotating Machinery Based on Multi-Scale Hybrid Features and Improved Convolutional Neural Networks.

Rotating machinery is susceptible to harsh environmental interference, and fault signal features are challenging to extract, leading to difficulties in health status recognition. This paper proposes multi-scale hybrid features and improved convolutional neural networks (MSCCNN) health status identification methods for rotating machinery. Firstly, the rotating machinery vibration signal is decomposed into intrinsic modal components (IMF) using empirical wavelet decomposition, and multi-scale hybrid feature sets are constructed by simultaneously extracting time-domain, frequency-domain and time-frequency-domain features based on the original vibration signal and the intrinsic modal components it decomposes. Secondly, using correlation coefficients to select features sensitive to degradation, construct rotating machinery health indicators based on kernel principal component analysis and complete health state classification. Finally, a convolutional neural network model (MSCCNN) incorporating multi-scale convolution and hybrid attention mechanism modules is developed for health state identification of rotating machinery, and an improved custom loss function is applied to improve the superiority and generalization ability of the model. The bearing degradation data set of Xi'an Jiaotong University is used to verify the effectiveness of the model. The recognition accuracy of the model is 98.22%, which is 5.83%, 3.30%, 2.29%, 1.52%, and 4.31% higher than that of SVM, CNN, CNN + CBAM, MSCNN, and MSCCNN + conventional features, respectively. The PHM2012 challenge dataset is used to increase the number of samples to validate the model effectiveness, and the model recognition accuracy is 97.67%, which is 5.63%, 1.88%, 1.36%, 1.49%, and 3.69% higher compared to SVM, CNN, CNN + CBAM, MSCNN, and MSCCNN + conventional features methods, respectively. The MSCCNN model recognition accuracy is 98.67% when validated on the degraded dataset of the reducer platform.

LPA1-mediated PKD2 activation promotes LPA-induced tissue factor expression via the p38α and JNK2 MAPK pathways in smooth muscle cells.

Tissue factor (TF) is the principal initiator of blood coagulation and is necessary for thrombosis. We previously reported that lysophosphatidic acid (LPA), a potent bioactive lipid, highly induces TF expression at the transcriptional level in vascular smooth muscle cells. To date, however, the specific role of the LPA receptor is unknown, and the intracellular signaling pathways that lead to LPA induction of TF have been largely undetermined. In the current study, we found that LPA markedly induced protein kinase D (PKD) activation in mouse aortic smooth muscle cells (MASMCs). Small-interfering RNA-mediated knockdown of PKD2 blocked LPA-induced TF expression and activity, indicating that PKD2 is the key intracellular mediator of LPA signaling leading to the expression and cell surface activity of TF. Furthermore, our data reveal a novel finding that PKD2 mediates LPA-induced TF expression via the p38α and JNK2 MAPK signaling pathways, which are accompanied by the PKD-independent MEK1/2-ERK-JNK pathway. To identify the LPA receptor(s) responsible for LPA-induced TF expression, we isolated MASMCs from LPA receptor-knockout mice. Our results demonstrated that SMCs isolated from LPA receptor 1 (LPA1)-deficient mice completely lost responsiveness to LPA stimulation, which mediates induction of TF expression and activation of PKD and p38/JNK MAPK, indicating that LPA1 is responsible for PKD2-mediated activation of JNK2 and p38α. Taken together, our data reveal a new signaling mechanism in which the LPA1-PKD2 axis mediates LPA-induced TF expression via the p38α and JNK2 pathways. This finding provides new insights into LPA signaling, the PKD2 pathway, and the mechanisms of coagulation/atherothrombosis.

Bak interacts with AKT and is involved in TNFα/CHX-induced apoptosis.

Bak is important for TNFα/CHX-induced neuronal death, but the precise molecular mechanism remains unclear. At the same time, TNFα/CHX concomitantly activates the phosphorylation of the MAPK and PI3K/AKT kinases. This study for the first time clarified the association between the MAPK and AKT under the TNFα/CHX stimulation upon addition of different kinase inhibitors to show whether Bak is associated with the kinase activation. The bioinformatics software HDOCK predicted the interaction between Bak and AKT. The addition of TNFα/CHX was proposed to destroy the complex, such that the dissociated Bak would exert a proapoptosis effect AKT can influence the inhibition of cell apoptosis. There was no cell death upon inducing TNFα/CHX for 3 h. AKT was less obvious with apoptosis but in the Bak knockout cells, the anti-apoptotic effect of AKT was very obvious. This study, therefore, provides the theoretical basis for the molecular mechanism of apoptosis induced by TNFα/CHX, providing a new target and direction for studying drug resistance.

Highly potent multivalent VHH antibodies against Chikungunya isolated from an alpaca naïve phage display library.

BACKGROUND: Chikungunya virus (CHIKV) is a re-emerged mosquito-borne alphavirus that can cause musculoskeletal diseases, imposing a substantial threat to public health globally. High-affinity antibodies are need for diagnosis and treatment of CHIKV infections. As a potential diagnostic and therapeutic agent, the multivalent VHH antibodies is a promising tookit in nanomedicine. Here, we developed potent multivalent VHH antibodies from an alpaca naïve phage display library targeting the E2 glycoprotein of the CHIKV virus. RESULTS: In the present study, we generated 20 VHH antibodies using a naïve phage display library for binders to the CHIKV E2 glycoprotein. Of these, multivalent VHH antibodies Nb-2E8 and Nb-3C5 had specific high-affinity binding to E2 protein within the nanomolar range. The equilibrium dissociation constant (KD) was between 2.59-20.7 nM, which was 100-fold stronger than the monovalent antibodies' affinity. Moreover, epitope mapping showed that Nb-2E8 and Nb-3C5 recognized different linear epitopes located on the E2 glycoprotein domain C and A, respectively. A facile protocol of sandwich ELISA was established using BiNb-2E8 as a capture antibody and HRP-conjugated BiNb-3C5 as a detection antibody. A good linear correlation was achieved between the OD450 value and the E2 protein concentration in the 5-1000 ng/mL range (r = 0.9864, P < 0.0001), indicating its potential for quantitative detection of the E2 protein. CONCLUSIONS: Compared to monovalent antibodies, multivalent VHH antibodies Nb-2E8 and Nb-3C5 showed high affinity and are potential candidates for diagnostic applications to better detect CHIKV virions in sera.

Fe3O4@polydopamine nanoparticle-loaded human umbilical cord mesenchymal stem cells improve the cognitive function in Alzheimer's disease mice by promoting hippocampal neurogenesis.

One of the most promising treatments for neurodegenerative diseases is the stem cell therapy; however, there are still some limitations in the treatment of Alzheimer's disease. In this study, superparamagnetic nanoparticles composed of magnetic Fe3O4 and polydopamine shells were used to label human umbilical cord mesenchymal stem cells (hUC-MSCs) in order to increase the targeting of hUC-MSCs. Our data suggested that Fe3O4@PDA labeling increase the efficiency of hUC-MSCs entering the brain. Moreover, the water maze test showed that compared with hUC-MSCs only, Fe3O4@PDA-labeled hUC-MSCs improved the cognitive ability of APP/PS1 transgenic mice more significantly. Other experimental data showed that the expression of essential proteins in the hippocampus, such as Aß, synaptophysin, brain-derived neurotrophic factor, are affected by Fe3O4@PDA coated-hUC-MSCs. The regulation of Fe3O4@PDA coated-hUC-MSCs could improve the memory and cognitive ability of AD mice by excessive generation of neuroprotective factors, which might be considered a viable therapy to treat AD.

Seroreactive Profiling of Filoviruses in Chinese Bats Reveals Extensive Infection of Diverse Viruses.

Southern China is a hot spot of emerging infectious diseases, in which diverse species of bats dwell, a large group of flying mammals considered natural reservoirs for zoonotic viruses. Recently, divergent filoviruses (FiVs) have been identified in bats within this region, which pose a potential risk to public health, but the true infection situation in bats remains largely unclear. Here, 689 archived bat serum samples were analyzed by enzyme-linked immunosorbent assay (ELISA), Western blotting, and neutralization assay to investigate the seroprevalence and cross-reactivity of four divergent FiVs and two other viruses (rabies virus and Tuhoko pararubulavirus 1) of different families within the order Mononegavirales Results showed no cross-antigenicity between FiVs and other mononegaviruses but different cross-reactivity among the FiVs themselves. The total FiV seroreactive rate was 36.3% (250/689), with infection by the indigenous Chinese FiV DH04 or an antigenically related one being the most widely and the most highly prevalent. Further viral metagenomic analysis of fruit bat tissues also identified the gene sequence of a novel FiV. These results indicate the likely prevalence of other so far unidentified FiVs within the Chinese bat population, with frugivorous Rousettus leschenaultii and Eonycteris spelaea bats and insectivorous Myotis horsfieldii and Miniopterus schreibersii bats being their major reservoirs.IMPORTANCE Bats are natural hosts of many FiVs, from which diverse FiVs were serologically or virologically detected in Africa, Europe, and East Asia. Recently, very divergent FiVs were identified in the Chinese bat population, but their antigenic relationship with other known FiVs remains unknown. Here, we conducted serological characterization and investigation of Chinese indigenous FiVs and prototypes of other viruses in bats. Results indicated that Chinese indigenous FiVs are antigenically distant to other FiVs, and infection of novel or multiple FiVs occurred in Chinese bats, with FiV DH04 or an antigenically related one being the most widely and the most highly prevalent. Additionally, besides Rousettus leschenaultii and Eonycteris spelaea bats, the insectivorous Myotis horsfieldii and M. schreibersii bats are highly preferential hosts of FiVs. Seroreactive and viral metagenomic results indicated that more as yet unknown bat-borne FiVs circulate in Southern China, and to uncover them further, investigation and timely surveillance is needed.

Extensive Genetic Diversity of Polyomaviruses in Sympatric Bat Communities: Host Switching versus Coevolution.

Polyomaviruses (PyVs) are small DNA viruses carried by diverse vertebrates. The evolutionary relationships of viruses and hosts remain largely unclear due to very limited surveillance in sympatric communities. In order to investigate whether PyVs can transmit among different mammalian species and to identify host-switching events in the field, we conducted a systematic study of a large collection of bats (n = 1,083) from 29 sympatric communities across China which contained multiple species with frequent contact. PyVs were detected in 21 bat communities, with 192 PyVs identified in 186 bats from 15 species within 6 families representing at least 28 newly described PyVs. Surveillance results and phylogenetic analyses surprisingly revealed three interfamily PyV host-switching events in these sympatric bat communities: two distinct PyVs were identified in two bat species in restricted geographical locations, while another PyV clustered phylogenetically with PyVs carried by bats from a different host family. Virus-host relationships of all discovered PyVs were also evaluated, and no additional host-switching events were found. PyVs were identified in different horseshoe bat species in sympatric communities without observation of host-switching events, showed high genomic identities, and clustered with each other. This suggested that even for PyVs with high genomic identities in closely related host species, the potential for host switching is low. In summary, our findings revealed that PyV host switching in sympatric bat communities can occur but is limited and that host switching of bat-borne PyVs is relatively rare on the predominantly evolutionary background of codivergence with their hosts.IMPORTANCE Since the discovery of murine polyomavirus in the 1950s, polyomaviruses (PyVs) have been considered highly host restricted in mammals. Sympatric bat communities commonly contain several different bat species in an ecological niche facilitating viral transmission, and they therefore represent a model to identify host-switching events of PyVs. In this study, we screened PyVs in a large number of bats in sympatric communities from diverse habitats across China. We provide evidence that cross-species bat-borne PyV transmission exists, though is limited, and that host-switching events appear relatively rare during the evolutionary history of these viruses. PyVs with close genomic identities were also identified in different bat species without host-switching events. Based on these findings, we propose an evolutionary scheme for bat-borne PyVs in which limited host-switching events occur on the background of codivergence and lineage duplication, generating the viral genetic diversity in bats.

Seroprevalence, cross antigenicity and circulation sphere of bat-borne hantaviruses revealed by serological and antigenic analyses.

Bats are newly identified reservoirs of hantaviruses (HVs) among which very divergent HVs have been discovered in recent years. However, their significance for public health remains unclear since their seroprevalence as well as antigenic relationship with human-infecting HVs have not been investigated. In the present study archived tissues of 1,419 bats of 22 species from 6 families collected in 5 south and southwest provinces in China were screened by pan-HV RT-PCR following viral metagenomic analysis. As a result nine HVs have been identified in two bat species in two provinces and phylogenetically classified into two species, Laibin virus (LAIV, ICTV approved species, 1 strain) and Xuan son virus (XSV, proposed species, 8 strains). Additionally, 709 serum samples of these bats were also analyzed by ELISA to investigate the seroprevalence and cross-reactivity between different HVs using expressed recombinant nucleocapsid proteins (rNPs) of LAIV, XSV and Seoul virus (SEOV). The cross-reactivity of some bat sera were further confirmed by western blot (WB) using three rNPs followed by fluorescent antibody virus neutralization test (FAVNT) against live SEOV. Results showed that the total HV seropositive rate of bat sera was 18.5% (131/709) with many cross reacting with two or all three rNPs and several able to neutralize SEOV. WB analysis using the three rNPs and their specific hyperimmune sera demonstrated cross-reactivity between XSV/SEOV and LAIV/XSV, but not LAIV/SEOV, indicating that XSV is antigenically closer to human-infecting HVs. In addition a study of the distribution of the viruses identified an area covering the region between Chinese Guangxi and North Vietnam, in which XSV and LAIV circulate within different bat colonies with a high seroprevalence. A circulation sphere of bat-borne HVs has therefore been proposed.

Cd-Based Metal-Organic Framework for Selective Turn-On Fluorescent DMSO Residual Sensing.

Dimethyl sulfoxide (DMSO) is a universally used solvent in various synthetic reactions, and trace amounts of DMSO residual are often seen on the surface of chemical product. It is difficult to quickly determine whether the residual DMSO is washed completely. This work reports a CdII metal-organic framework (MOF) SXU-4 which can detect trace amounts of DMSO in various solvents. Fluorescence experiments reveal its turn-on fluorescence effect toward DMSO with high selectivity and sensitivity, indicating that it can be used as an effective luminescent probe for rapid chemical product purity detection by testing the washing solution. Crystallographically characterized DMSO loaded SXU-4 (DMSO@SXU-4), in combination with computational results uncover that the enhanced DMSO-MOF conjugation through multiple DMSO-MOF supramolecule interactions and charge rearrangement are the main causes of fluorescence intensification.

Polyoxotitanate Molecular Cage Featuring Four Types of Ethylenediamines: Formation Mechanism Insight from Host-Guest Interaction and Crystallographic Study.

Titanium-oxide or polyoxotitanate clusters are a new type of inorganic host materials that can encapsulate inorganic molecules or ions. We report herein a (NH4)4(enH2)[Ti18O27(PhCOO)24(en)9] molecular cage (Ti18) that encapsulates an entire organic ethylenediamine (en) ion. A thorough investigation has revealed the extraordinary versatility of en. Besides being a guest cation, it also functions as chelating and bridging ligand. It balances the charge of the negative Ti18 cage and facilitates the deprotonation of benzoic acid at the early stage of the reaction as well. DFT calculation and a derivative of Ti18 with open sites at its equatorial position shed further light on the formation mechanism. Ti18 strongly absorbs visible light as a result of en coordination, and it exhibits superior photocatalytic activity compared to anatase TiO2.

A One-Dimensional Broadband Emissive Hybrid Lead Iodide with Face-Sharing PbI6 Octahedral Chains.

One-dimensional (1D) organic-inorganic hybrid lead halides with unique core-shell quantum wire structures and splendid photoluminescence properties have been considered one of the most promising high-efficiency broadband emitters. However, studies on the broadband emissions in 1D purely face-shared lead iodide hybrids are still rare so far. Herein, we report on a new 1D lead iodide hybrid, (2cepyH)PbI3 (2cepy = 1-(2-chloroethyl)pyrrolidine), characterized with face-sharing PbI6 octahedral chains. Upon UV photoexcitation, this material shows broadband yellow emissions originating from the self-trapped excitons associated with distorted Pb-I lattices on account of the strong exciton-phonon coupling, as proved by variable-temperature emission spectra. Moreover, experimental and calculated results reveal that (2cepyH)PbI3 is an indirect bandgap semiconductor, the band structures of which are governed by inorganic parts. Our work represents the first broadband emitter based on a 1D face-shared lead iodide hybrid and opens a new way to obtain the novel broadband emission materials.

Emergent chikungunya fever and vertical transmission in Yunnan Province, China, 2019.

During the dengue epidemic in Yunnan Province, China, during 2019, a concurrent outbreak of chikungunya occurred in the city of Ruili, which is located in the southwest of the province, adjacent to Myanmar. As part of this outbreak, three neonatal cases of infection with indigenous chikungunya virus from mother-to-child (vertical) transmission were observed. Isolates of chikungunya virus were obtained from 37 serum samples of patients with chikungunya during this outbreak, and a phylogenetic analysis of these isolates revealed that they belong to the Indian Ocean subclade of the East/Central/South African genotype. The E1 genes of these viruses did not harbor the A226V mutation.

Response of periphytic biofilm in water to estrone exposure: Phenomenon and mechanism.

The responses of pure strains to contaminant (i.e., estrone, E1) exposure have been widely studied. However, few studies about the responses of multispecies microbial aggregates (e.g., periphytic biofilm) to E1 exposure are available. In this study, the changes in physiological activity and community composition of periphytic biofilms before and after E1 exposure were investigated. The results showed that periphytic biofilms exhibited high adaptability to E1 exposure at a concentration of 0.5 mg L-1 based on physiological results. The increase in productivity of extracellular polymeric substances (EPS) after exposure to E1 was the main factor preventing association between E1 and microbial cells. The increase in the activity of superoxide dismutase (SOD) and ATP enzyme activity and the change in the co-occurrence pattern of microbial communities (increasing the relative abundance of Xanthomonadaceae and Cryomorphacea) also protected biofilms from E1 exposure. However, exposure to a high concentration of E1 (>10 mg L-1) significantly decreased EPS productivity and metabolic activity due to the excessive accumulation of reactive oxygen species. In addition, the abundance of some sensitive species, such as Pseudanabaenaceae, decreased sharply at this concentration. Overall, this study highlighted the feasibility of periphytic biofilms to adapt to E1 exposure at low concentrations in aquatic environments.

Transient Receptor Potential (TRP) Channels in the Pacific Oyster (Crassostrea gigas): Genome-Wide Identification and Expression Profiling after Heat Stress between C. gigas and C. angulata.

Transmembrane proteins are involved in an array of stress responses, particularly in thermo-sensation and thermo-regulation. In this study, we performed a genome-wide identification and characterization of the Transient Receptor Potential (TRP) genes in the Pacific oyster (Crassostrea gigas) and investigated their expression profiles after heat stress to identify critical TRPs potentially associated with thermal regulation. A total of 66 TRP genes were identified in the C. gigas, which showed significant gene expansion and tandem duplication. Meta-analysis of the available RNA-Seq data generated from samples after acute heat stress revealed a set of heat-inducible TRPs. Further examination of their expression profiles under chronic heat stress, and comparison between C. gigas and C. angulata, two oyster species with different tolerance levels to heat stress, led to the identification of TRPC3.6, TRPC3.7, and TRPV4.7 as important TRPs involved in thermal regulation in oysters. This work provided valuable information for future studies on the molecular mechanism of TRP mediated thermal tolerance, and identification of diagnostic biomarker for thermal stress in the oysters.

Insulin-Like Peptide Receptor-Mediated Signaling Pathways Orchestrate Regulation of Growth in the Pacific Oyster (Crassostrea gigas), as Revealed by Gene Expression Profiles.

The involvement of insulin/insulin-like growth factor signaling (IIS) pathways in the growth regulation of marine invertebrates remains largely unexplored. In this study, we used a fast-growing Pacific oyster (Crassostrea gigas) variety "Haida No.1" as the material with which to unravel the role of IIS systems in growth regulation in oysters. Systematic bioinformatics analyses allowed us to identify major components of the IIS signaling pathway and insulin-like peptide receptor (ILPR)-mediated signaling pathways, including PI3K-AKT, RAS-MAPK, and TOR, in C. gigas. The expression levels of the major genes in IIS and its downstream signaling pathways were significantly higher in "Haida No.1" than in wild oysters, suggesting their involvement in the growth regulation of C. gigas. The expression profiles of IIS and its downstream signaling pathway genes were significantly altered by nutrient abundance and culture temperature. These results suggest that the IIS signaling pathway coupled with the ILPR-mediated signaling pathways orchestrate the regulation of energy metabolism to control growth in Pacific oysters.

Genuine Active Species Generated from Fe3 N Nanotube by Synergistic CoNi Doping for Boosted Oxygen Evolution Catalysis.

The surface reconstruction of oxygen evolution reaction (OER) catalysts has been proven favorable for enhancing its catalytic activity. However, what is the active site and how to promote the active species generation remain unclear and are still under debate. Here, the in situ synthesis of CoNi incorporated Fe3 N nanotubes (CoNi-Fe3 N) on the iron foil through the anodization/electrodeposition/nitridation process for use of boosted OER catalysis is reported. The synergistic CoNi doping induces the lattice expansion and up shifts the d-band center of Fe3 N, which enhances the adsorption of hydroxyl groups from electrolyte during the OER catalysis, facilitating the generation of active CoNi-FeOOH on the Fe3 N nanotube surface. As a result of this OER-conditioned surface reconstruction, the optimized catalyst requires an overpotential of only 285 mV at a current density of 10 mA cm-2 with a Tafel slope of 34 mV dec-1 , outperforming commercial RuO2 catalysts. Density functional theory (DFT) calculations further reveal that the Ni site in CoNi-FeOOH modulates the adsorption of OER intermediates and delivers a lower overpotential than those from Fe and Co sites, serving as the optimal active site for excellent OER performance.