1.The Structure and Function of The YopJ Family Effectors in The Bacterial Type III Secretion System
Ao-Ning LI ; Wen-Bo LI ; Yu-Ying LU ; Min-Hui ZHU ; Yu-Long QIN ; Yong ZHAO ; Zhao-Huan ZHANG
Progress in Biochemistry and Biophysics 2026;53(3):516-533
The Type III Secretion System (T3SS) serves as a pivotal virulence apparatus for numerous Gram-negative bacterial pathogens, enabling them to infect both animal and plant hosts. Functioning as a molecular syringe, the T3SS directly translocates bacterial effector proteins from the bacterial cytoplasm into the interior of eukaryotic host cells. These effectors are central weapons that precisely manipulate a wide spectrum of host cellular physiological processes, ranging from cytoskeletal dynamics to immune signaling, to establish a favorable niche for bacterial survival and proliferation. Among the diverse arsenal of T3SS effectors, the YopJ family constitutes a critical group of virulence factors. Members of this family are characterized by a conserved catalytic triad structure—a hallmark of the CE clan of cysteine proteases that has been evolutionarily repurposed to confer acetyltransferase activity. A defining and intriguing feature of these enzymes is their stringent dependence on a host-derived eukaryotic cofactor, inositol hexakisphosphate (IP6), for allosteric activation. This requirement acts as a sophisticated molecular safeguard, ensuring enzymatic activity only within the appropriate host environment, thereby preventing detrimental effects on the bacterium itself. While seminal studies on individual members such as Yersinia’s YopJ and Salmonella’s AvrA have provided deep mechanistic insights, a systematic and integrative understanding of the structure-function relationships across the entire family remains fragmented. Key questions persist regarding how a conserved catalytic core has diverged to recognize distinct host substrates in different kingdoms of life. To address this gap, this article provides a systematic review of the YopJ family, focusing on three interconnected aspects: their structural features, their catalytic mechanism, and their divergent immunosuppressive strategies in animal versus plant hosts. By conducting a comparative analysis of the sequences and resolved three-dimensional structures of three representative members (e.g., HopZ1a, PopP2, AvrA), we elucidate regions of significant variation embedded within the conserved core catalytic architecture. These variable regions, often involving surface loops and substrate-binding interfaces, are crucial determinants of target specificity and functional specialization. The functional divergence of this effector family is most apparent when comparing their modes of action in different hosts. In animal hosts, YopJ-family effectors primarily sabotage innate immune signaling pathways. They achieve this by acetylating key serine and threonine residues within the activation loops of critical kinases in the MAPK and NF‑κB pathways. This post-translational modification blocks the phosphorylation and subsequent activation of these kinases, leading to potent suppression of inflammatory cytokine production. Conversely, in plant hosts, the strategy broadens to dismantle the two-tiered plant immune system. YopJ homologs target a more diverse set of substrates, including immune-associated receptor-like cytoplasmic kinases (RLCKs), microtubule networks via tubulin acetylation (which disrupts cellular trafficking and signaling), and transcription factors central to defense gene regulation. This multi-target approach effectively suppresses both Pattern-Triggered Immunity (PTI) and Effector-Triggered Immunity (ETI). In conclusion, this synthesis aims to deepen the mechanistic understanding of YopJ family-mediated pathogenesis by integrating structural biology with cellular function across host kingdoms. Elucidating the precise molecular basis for substrate selection—how conserved platforms achieve target diversity—is a major frontier. Furthermore, this knowledge provides a vital theoretical foundation for developing novel anti-virulence strategies. Targeting the conserved IP6-binding pocket or the catalytic acetyltransferase activity itself represents a promising avenue for designing broad-spectrum inhibitors that could disarm this critical family of bacterial effectors, potentially offering new therapeutic approaches against a range of pathogenic bacteria.
2.Clinical efficacy of demineralized dentin matrix particles in immediate implantation for bone defects in posterior region: a 1 to 5-year follow-up study.
Hao WU ; Ning CAO ; Liangwei CAO ; Fei YU ; Xu ZHANG ; Shibo WEI ; Hongwu WEI ; Shuigen GUO
West China Journal of Stomatology 2025;43(4):570-583
OBJECTIVES:
This study aims to evaluate the short- to medium-term clinical efficacy of demineralized dentin matrix (DDM) particles applied during the immediate implantation of alveolar bone defects in the posterior region.
METHODS:
A total of 76 patients with 110 simple taper retentive implants were included in the conducted study and divided into Groups A and B in accordance with the bone grafting materials. Cone beam computed tomography and panoramic radiographs were taken immediately after implant surgery, immediate crown repair, and final follow-up time. The average follow-up time for Groups A and B was recorded. The primary observed clinical indicators were overall survival rate of the implant, bone resorption of the mesial and distal margins of the implant, buccal bone width resorption at the platform level and 1 mm below the platform, and bone height of the implant. Implant complication was a secondary observed clinical indicator.
RESULTS:
During the 1-to-5-year follow-up observation period, the mean follow-up of Group A was 38.2 months while that of Group B was 39.9 months. In Group A, two implants failed, one of which fractured, and implant overall survival rate was 96.4%. Four implants failed in Group B due to peri-implantitis, and implant overall survival rate was 92.6%. No statistically significant difference in implant overall survival rate was found between the two groups (P>0.05). In Group A, the average bone resorption in the mesial and distal margins of the implants was (1.011±2.047) mm and (0.841±2.183) mm, respectively. In Group B, the average bone resorption of the mesial and distal margins of the implants was (1.546±1.778) mm and (1.431±1.909) mm, respectively. No statistically significant difference was noted between the two groups (P>0.05). In Group A, buccal bone width resorption at the platform level and 1 mm below the platform of the implant was (0.782±2.084) mm and (0.681±2.307) mm, respectively. In Group B, buccal bone width resorption at the platform level and 1 mm below the platform of implant was (1.071±1.474) mm and (0.949±1.909) mm, respectively. No statistically significant difference was found between the two groups (P>0.05). In Group A, the buccal bone height of resorption of the implant was (1.044±2.214) mm. In Group B, the buccal bone height of resorption of the implant was (1.075±1.456) mm. No statistically significant difference in bone height was observed between the two groups (P>0.05).
CONCLUSIONS
During the 1-to-5-year follow-up observation period, DDM particles can effectively increase the height and width of alveolar bone, and they can achieve the same effect of maintaining alveolar bone contour and bone augmentation compared with deproteinized inorganic calf bone. DDM particles can be used as a potential new bone grafting material for the treatment of bone defects in clinical practice.
Humans
;
Follow-Up Studies
;
Dentin
;
Cone-Beam Computed Tomography
;
Dental Implants
;
Male
;
Female
;
Adult
;
Alveolar Bone Loss/surgery*
;
Middle Aged
;
Bone Transplantation
;
Radiography, Panoramic
;
Dental Implantation, Endosseous/methods*
;
Immediate Dental Implant Loading
3.Analysis of risk factors for early failure of simple taper retentive implants.
Xu ZHANG ; Zengxuan WAN ; Shibo WEI ; Fei YU ; Ning CAO ; Liangwei CAO ; Hao WU ; Shuigen GUO ; Hongwu WEI
West China Journal of Stomatology 2025;43(6):780-788
OBJECTIVES:
To explore the related risk factors of early failure of simple taper retentive implants, and to provide theoretical guidance for clinical work.
METHODS:
Collect cases of patients who visited the Department of Stomatology of the Fourth Affiliated Hospital of Nanchang University from January 2021 to June 2024, received simple taper retentive implants, and had complete medical records. Taking the implants as the unit, analyze the influence of patient-related factors (gender, age, smoking history, hypertension history, diabetes history), implant-related factors (implant length, implant diameter, implant surface treatment), and surgical-related factors (implant site, implant timing, simultaneous maxillary sinus floor elevation, simultaneous bone augmentation) on the early failure of implants. Univariate analysis and multivariate analysis were adopted to explore the potential risk factors for early failure of simple taper retentive implants.
RESULTS:
A total of 3,533 simple taper retentive from 1,681 patients were included during the study period. Among them, 53 implants from 49 patients experienced early failure, with an early failure rate of 2.9% at the patient le-vel and 1.5% at the implant level. Multivariate analysis revealed that smoking (OR=2.148, P=0.021), the anterior mandibular region (OR=3.669, P=0.006), and the posterior maxillary region (OR=2.191, P=0.033) were risk factors for early failure of simple taper retentive implants. In the univariate analysis, simultaneous maxillary sinus floor elevation had a higher risk of early failure, but this effects was no longer significant in the multivariate analysis (P>0.05).
CONCLUSIONS
Smoking, the anterior mandibular region, and the posterior maxillary region are risk factors for the early failure of simple taper retentive implants, and could be comprehensively considered in the preoperative treatment plan.
Humans
;
Risk Factors
;
Male
;
Female
;
Middle Aged
;
Dental Implants
;
Adult
;
Smoking/adverse effects*
;
Dental Restoration Failure
;
Aged
4.Screening key genes of PANoptosis in hepatic ischemia-reperfusion injury based on bioinformatics
Lirong ZHU ; Qian GUO ; Jie YANG ; Qiuwen ZHANG ; Guining HE ; Yanqing YU ; Ning WEN ; Jianhui DONG ; Haibin LI ; Xuyong SUN
Organ Transplantation 2025;16(1):106-113
Objective To explore the relationship between PANoptosis and hepatic ischemia-reperfusion injury (HIRI), and to screen the key genes of PANoptosis in HIRI. Methods PANoptosis-related differentially expressed genes (PDG) were obtained through the Gene Expression Omnibus database and GeneCards database. Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Set Enrichment Analysis (GSEA) were used to explore the biological pathways related to PDG. A protein-protein interaction network was constructed. Key genes were selected, and their diagnostic value was assessed and validated in the HIRI mice. Immune cell infiltration analysis was performed based on the cell-type identification by estimating relative subsets of RNA transcripts. Results A total of 16 PDG were identified. GO analysis showed that PDG were closely related to cellular metabolism. KEGG analysis indicated that PDG were mainly enriched in cellular death pathways such as apoptosis and immune-related signaling pathways such as the tumor necrosis factor signaling pathway. GSEA results showed that key genes were mainly enriched in immune-related signaling pathways such as the mitogen-activated protein kinase (MAPK) signaling pathway. Two key genes, DFFB and TNFSF10, were identified with high accuracy in diagnosing HIRI, with areas under the curve of 0.964 and 1.000, respectively. Immune infiltration analysis showed that the control group had more infiltration of resting natural killer cells, M2 macrophages, etc., while the HIRI group had more infiltration of M0 macrophages, neutrophils, and naive B cells. Real-time quantitative polymerase chain reaction results showed that compared with the Sham group, the relative expression of DFFB messenger RNA in liver tissue of HIRI group mice increased, and the relative expression of TNFSF10 messenger RNA decreased. Cibersort analysis showed that the infiltration abundance of naive B cells was positively correlated with DFFB expression (r=0.70, P=0.035), and the infiltration abundance of M2 macrophages was positively correlated with TNFSF10 expression (r=0.68, P=0.045). Conclusions PANoptosis-related genes DFFB and TNFSF10 may be potential biomarkers and therapeutic targets for HIRI.
5.Effect of Dingzhi Xiaowan on PI3K/Akt/mTOR/HIF-1α Pathway in Post-stroke Cognitive Impairment Model Mice
Han ZHANG ; Yu WANG ; Xiaoqin ZHONG ; Zhenqiu NING ; Dafeng HU ; Minzhen DENG
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(5):1-11
ObjectiveTo investigate the effect of Dingzhi Xiaowan (DZXW) in post-stroke cognitive impairment (PSCI) model mice. MethodsThe cerebral ischemia-reperfusion injury model of mice was established by using the middle cerebral artery occlusion method. Forty C57BL/6 male mice were randomly divided into the sham operation group, model group, low-dose DZXW group (1.43 g·kg-1), and high-dose DZXW group (2.56 g·kg-1), with 10 mice in each group. Both the sham operation group and the model group were treated with equal amounts of normal saline by gavage, and the above four groups of mice were gavaged once a day for 30 consecutive days. Morris water maze test was used to evaluate the learning memory ability of mice. Serum levels of amyloid precursor protein (APP), amyloid 42 (Aβ42), acetylcholinesterase (AChE), and superoxide dismutase (SOD) were measured by enzyme-linked immunosorbent assay (ELISA). Deoxyribonucleotide end transferase-mediated nick end labelling (TUNEL) assay was applied to detect the degree of apoptosis in the mouse's hippocampal neurons. Western blot was used to detect the protein expression of phosphoinositol-3 kinase (PI3K), protein kinase B (Akt), mammalian target of rapamycin (mTOR), hypoxia-inducible factor 1-alpha (HIF-1α), B-cell lymphoma 2 (Bcl-2) homologous structural domain protein (Beclin1), sequestosome 1 (p62), microtubule-associated protein light chain 3 (LC3), Bcl-2, and Bcl-2-associated X protein (Bax) in hippocampal tissue. Prussian blue staining was used to detect iron deposition in hippocampal tissue. Transmission electron microscopy was taken to observe the ultrastructure of the mouse's hippocampal neurons. ResultsCompared with the sham operation group, the latency, APP, Aβ42, AChE, TUNEL positivity, ferric ion deposition, HIF-1α, Beclin1, Bax, and LC3Ⅱ/Ⅰ were significantly increased in the model group (P<0.01), while the number of crossing platforms, SOD, p-PI3K, p-Akt, p-mTOR, p62, and Bcl-2 were significantly decreased (P<0.01). Compared with the model group, the latency, APP, Aβ42, AChE, TUNEL positivity rate, ferric ion deposition, HIF-1α, Beclin1, Bax, and LC3Ⅱ/Ⅰ were significantly reduced in the DZXW groups (P<0.05), while the number of crossing platforms, SOD, p-PI3K, p-Akt, p-mTOR, p62, and Bcl-2 were significantly higher (P<0.05). ConclusionDZXW can alleviate cognitive impairment induced by oxidative stress-aggravated hippocampal neuronal damage in PSCI model mice by modulating the PI3K/Akt/mTOR/HIF-1α autophagy signalling pathway.
6.Palpitations, Shortness of Breath, Weakness in Limbs, Edema, and Dyspnea: A Rare Inflammatory Myopathy with Positive Aniti-mitochondrial Antibodies and Cardiac Involvement
Chunsu LIANG ; Xuchang ZHANG ; Ning ZHANG ; Lin KANG ; Xiaohong LIU ; Jiaqi YU ; Yingxian LIU ; Lin QIAO ; Yanli YANG ; Xiaoyi ZHAO ; Ruijie ZHAO ; Na NIU ; Xuelian YAN
Medical Journal of Peking Union Medical College Hospital 2025;16(1):248-255
This article presents a case study of a patient who visited the Geriatric Department of Peking Union Medical College Hospital due to "palpitations, shortness of breath for more than 2 years, limb weakness for 6 months, edema, and nocturnal dyspnea for 2 months". The patient exhibited decreased muscle strength in the limbs and involvement of swallowing and respiratory muscles, alongside complications of heart failure and various arrhythmias which were predominantly atrial. Laboratory tests revealed the presence of multiple autoantibodies and notably anti-mitochondrial antibodies. Following a comprehensive multidisciplinary evaluation, the patient was diagnosed with anti-mitochondrial antibody-associated inflammatory myopathy. Treatment involved a combination of glucocorticoids and immunosuppressants, along with resistance exercises for muscle strength and rehabilitation training for lung function, resulting in significant improvement of clinical symptoms. The case underscores the importance of collaborative multidisciplinary approaches in diagnosing and treating rare diseases in elderly patients, where careful consideration of clinical manifestations and subtle abnormal clinical data can lead to effective interventions.
7.Study on the pollution and influencing factors of legionella pneumophila in industrial circulating cooling tower
Man YU ; Ying TANG ; Chenyi TAO ; Yong NING ; Yi XU ; Xia ZHANG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2025;43(2):122-128
Objective:To investigate the pollution status of legionella pneumophila of industrial circulating cooling towers, and explore the factors affecting the positive rate and quantity of legionella pneumophila, in order to provide data support for the risk assessment and hierarchical management of legionella pneumophila in workplaces.Methods:In February, May, August and October 2023, the cooling water samples were collected from a total of 20 industrial circulating cooling towers of 9 enterprises in an industrial park in Shanghai. The water temperature, free residual chlorine, total residual chlorine, turbidity, chroma, pH, conductivity, chemical oxygen consumption, iron content and total plate count in the water samples were detected. Meanwhile, the legionella pneumophila in the water samples were qualitatively and quantitatively analyzed, and the influence of water quality indexes on the positive rate and number of legionella pneumophila detected was analyzed by logistic regression and linear regression respectively.Results:The positive rates of legionella pneumophila in the first to fourth quarters of 20 industrial circulating cooling towers of 9 chemical enterprises were 35% (7/20), 45% (9/20), 45% (9/20), and 85% (17/20). The serotypes of legionella pneumophila detected in the cooling tower were mainly legionella pneumophila type 1 (95.2%, 40/42), and the number of legionella pneumophila ranged from 0.2 to 316.8 cfu/ml. Circulating cooling water temperature ( OR=1.36, 95% CI: 1.12-1.64, P=0.001) and conductivity ( OR=1.02, 95% CI: 1.00-1.03, P=0.026) were independent risk factors affecting the detection of legionella pneumophila. There was a positive correlation between chemical oxygen consumption and the detected amount of legionella pneumophila ( β=8.08, P=0.002) . Conclusion:The positive rate of legionella pneumophila in industrial circulating cooling water system is high, and the detected quantity fluctuates greatly, which may have health risks, suggesting that it is necessary to pay attention to the water quality management such as water temperature, conductivity and chemical oxygen consumption of industrial circulating cooling water and the monitoring and control of legionella pneumophila.
8.Construction of a recombinant adenovirus for Mycobacterium tuberculosis c-di-AMP phosphodiesterase expression and induction of humoral immunity
Jia-hao HU ; Huan-huan NING ; Meng-juan DONG ; Yan-zhi LU ; Ting DAI ; Cong-yue ZHANG ; Zi-qing XU ; Shu-yu WANG ; Zheng-yan ZHOU ; Yin-lan BAI
Chinese Journal of Zoonoses 2025;41(4):364-369
A recombinant adenovirus(rAd)for expression of Mycobacterium tuberculosis(M.tb)c-di-AMP phosphodiesterase CnpB was constructed,and its induced humoral immune response was detected.The codon-optimized gene of M.tb CnpB was cloned into the adenoviral plasmid pcADV.The recombinant plasmid pcADV-CnpB was transfected into HEK293T cells,and expression was detected with Western blot.The recombinant plasmid pcADV-CnpB and the backbone plasmid were co-transfected into HEK293T cells to obtain the recombinant adenovirus rAd-CnpB.rAd-CnpB was amplified in HEK293T cells,and the target protein expression of rAd-CnpB was detected with Western blot and immunofluorescence.Mice were immunized with rAd-CnpB intranasally,and their sera and bronchoalveolar lavage fluid(BALF)were collected.ELISA was used to detect levels of antigen-specific antibodies.Restriction enzyme digestion and sequencing indicated that the recombinant plasmid pcADV-CnpB was successfully constructed and led to protein expression in eukaryotic cells.rAd-CnpB was packaged and produced in HEK293T cells.After amplification and purification,rAd-CnpB with a titer of 5.53×1010 PFU/mL was obtained.rAd-CnpB led to CnpB expression in HEK293T cells.Intranasal immunization with rAd-CnpB increased levels of IgG and secretory IgA in BALF and led to high levels of IgG in sera.rAd-CnpB,the recombinant adenovirus for expression of c-di-AMP phosphodiesterase CnpB was successfully constructed,and was found to induce antigen-specific humoral and mucosal immune responses through mucosal immunization.Thus,rAd-CnpB may be used in further research on new TB vaccine strategies.
9.Regulation of white adipose tissue in mice by immunization with recombinant Bacillus Calmette-Gue?rin with c-di-AMP adjuvant
Meng-juan DONG ; Yu-xiao CHANG ; Huan-huan NING ; Yan-zhi LU ; Jian KANG ; Ming-ze XU ; Ting DAI ; Jia-ling LI ; Le-ran HAO ; Lin-na ZHANG ; Yin-lan BAI
Chinese Journal of Zoonoses 2025;41(4):370-375
This study assessed the role and mechanism of the recombinant Bacillus Calmette-Gue?rin vaccine(rBCG)with c-di-AMP adjuvant in regulating metabolism and immunity in epididymal white adipose(eWAT)in mice.Male C57BL/6 mice were intravenously immunized with BCG and rBCG,and their body weights were monitored.eWAT was isolated from the mice,and the stromal vascular fractions(SVFs)cell number was counted with a hemocytometer.Sections of mouse adipose tissue were prepared,and the size,number,and morphology of eWAT adipocytes and crown-like structure(CLS)formation were compared under a microscope after HE staining.The transcription levels of lipid metabolism-associated factors,cytokines and aging-associated genes in each group were determined with qRT-PCR.The body weights of mice gradually increased after immunization with BCG and rBCG.The proportions of eWAT increased,and the SVFs cell number decreased,in rBCG immunized mice.HE staining indicated that BCG immunization promoted hyperplasia,whereas rBCG immunization promoted hypertrophy of eWAT adipocytes;moreover,both BCG and rBCG immunization induced CLS formation in eWAT.The qRT-PCR results indicated that rBCG immunization inhibited the expression of genes associated with lipolysis and energy expenditure in eWAT.BCG immunization had little effect on cytokine transcription,whereas rBCG significantly induced the transcription of IFN-γ and IL-1Ra,and inhibited that of IL-15 and IL-2,but did not induce the expression of aging-associated genes.Thus,rBCG immunization induced eWAT adipocyte hypertrophy,which was associated with the inhibition of eWAT lipolysis and the regulation of cytokine expression.
10.Novel Structural Features of Isoflavone Synthase from Medicago truncatula Shed Light on Its Unique Enzymatic Mechanism
Chao SHI ; Zhao-Yang YE ; Fei XU ; Xiang-Ning DU ; Zhang-Xin CHEN ; Ming-Yue GU ; Jie DENG ; Wei WANG ; Liang-Yu LIU ; Mei-Ying WANG ; Xiao-Dong SU ; He-Li LIU ; Ming-Ying SHANG ; Li-Xin HUANG ; Zhen-Zhan CHANG
Chinese Journal of Biochemistry and Molecular Biology 2025;41(8):1204-1213,中插1-中插6
Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 ? by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Ⅰa-loop-helix Ⅰβ motif which cor-responds to helix Ⅰ of other P450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,the γ-domain.The structure reveals a homodimer in which the γ-domain of one molecule interacts with the β-domain of another.The plane of heme group makes an angle of ap-proximately 40° with the helix Ⅰa-loop-helix Ⅰβ motif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recogni-tion.Phe-301,Ser-303 and Gly-305 from the helix Ⅰa-loop-helix Ⅰβ motif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.

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