1.Syndrome Differentiation and Treatment of Asymptomatic Renal Hematuria Population Based on Association of Age-Constitution-Syndrome
Guangjian WANG ; Cong QIN ; Yibo WU ; Guodong YUAN ; Suzhi CHEN
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(9):247-255
For a long time, simple asymptomatic renal hematuria has not been taken seriously. Current studies have confirmed that renal hematuria is a risk factor for the progression of renal function, but there is no effective treatment available. Because asymptomatic renal hematuria is highly concealed and lacks typical symptoms, individualized syndrome differentiation in traditional Chinese medicine (TCM) is difficult, making it a challenge in clinical diagnosis and treatment. Although TCM has a long history and solid theoretical basis in the treatment of hematuria, it urgently needs to break through the bottleneck of traditional syndrome differentiation. Based on classical TCM theories, research achievements in modern constitution studies, and relevant clinical and pathological evidence, this article focuses on the decisive influence of age on constitution distribution and its regular association with the evolution of core syndromes, and constructs a three-dimensional diagnostic and therapeutic system of "age-constitution-syndrome". It reveals that the syndrome manifestations of asymptomatic renal hematuria are profoundly shaped by constitution, and that constitution shows a group distribution pattern with age-children often present with deficiency of lung and spleen Qi combined with wind-heat, young and middle-aged individuals often present with deficiency of liver and kidney Yin combined with deficient fire and stasis heat, and elderly individuals often present with deficiency of spleen and kidney combined with cold-dampness and stasis obstruction. By analyzing the common pathogenic mechanisms, outcome characteristics, and internal mechanisms among different age groups, this study provides a basic syndrome framework and core intervention strategies for specific populations in clinical practice, offering a new evidence-based approach to addressing the dilemma of “no identifiable syndrome”.
2.The Mechanism of Exercise Regulating Intestinal Flora in The Prevention and Treatment of Depression
Lei-Zi MIN ; Jing-Tong WANG ; Qing-Yuan WANG ; Yi-Cong CUI ; Rui WANG ; Xin-Dong MA
Progress in Biochemistry and Biophysics 2025;52(6):1418-1434
Depression, a prevalent mental disorder with significant socioeconomic burdens, underscores the urgent need for safe and effective non-pharmacological interventions. Recent advances in microbiome research have revealed the pivotal role of gut microbiota dysbiosis in the pathogenesis of depression. Concurrently, exercise, as a cost-effective and accessible intervention, has demonstrated remarkable efficacy in alleviating depressive symptoms. This comprehensive review synthesizes current evidence on the interplay among exercise, gut microbiota modulation, and depression, elucidating the mechanistic pathways through which exercise ameliorates depressive symptoms via the microbiota-gut-brain (MGB) axis. Depression is characterized by gut microbiota alterations, including reduced alpha and beta diversity, depletion of beneficial taxa (e.g., Bifidobacterium, Lactobacillus, and Coprococcus), and overgrowth of pro-inflammatory and pathogenic bacteria (e.g., Morganella, Klebsiella, and Enterobacteriaceae). Metagenomic analyses reveal disrupted metabolic functions in depressive patients, such as diminished synthesis of short-chain fatty acids (SCFAs), impaired tryptophan metabolism, and dysregulated bile acid conversion. For instance, Bifidobacterium longum deficiency correlates with reduced synthesis of neuroactive metabolites like homovanillic acid, while decreased Coprococcus abundance limits butyrate production, exacerbating neuroinflammation. Furthermore, elevated levels of indole derivatives from Clostridium species inhibit serotonin (5-HT) synthesis, contributing to depressive phenotypes. These dysbiotic profiles disrupt the MGB axis, triggering systemic inflammation, neurotransmitter imbalances, and hypothalamic-pituitary-adrenal (HPA) axis hyperactivity. Exercise exerts profound effects on gut microbiota composition, diversity, and metabolic activity. Longitudinal studies demonstrate that sustained aerobic exercise increases alpha diversity, enriches SCFA-producing genera (e.g., Faecalibacterium prausnitzii, Roseburia, and Akkermansia), and suppresses pathobionts (e.g., Desulfovibrio and Streptococcus). For example, a meta-analysis of 25 trials involving 1 044 participants confirmed that exercise enhances microbial richness and restores the Firmicutes/Bacteroidetes ratio, a biomarker of metabolic health. Notably, endurance training promotes Veillonella proliferation, which converts lactate into propionate, enhancing energy metabolism and delaying fatigue. Exercise also strengthens intestinal barrier integrity by upregulating tight junction proteins (e.g., ZO-1, occludin), thereby reducing lipopolysaccharide (LPS) translocation and systemic inflammation. However, excessive exercise may paradoxically diminish microbial diversity and exacerbate intestinal permeability, highlighting the importance of moderate intensity and duration. Exercise ameliorates depressive symptoms through multifaceted interactions with the gut microbiota, primarily via 4 interconnected pathways. First, exercise mitigates neuroinflammation by elevating anti-inflammatory SCFAs such as butyrate, which suppresses NF-κB signaling to attenuate microglial activation and oxidative stress in the hippocampus. Animal studies demonstrate that voluntary wheel running reduces hippocampal TNF‑α and IL-17 levels in stress-induced depression models, while fecal microbiota transplantation (FMT) from exercised mice reverses depressive behaviors by modulating the TLR4/NF‑κB pathway. Second, exercise regulates neurotransmitter dynamics by enriching GABA-producing Lactobacillus and Bifidobacterium, thereby counteracting neuronal hyperexcitability. Aerobic exercise also enhances the abundance of Lactobacillus plantarum and Streptococcus thermophilus, which facilitate 5-HT and dopamine synthesis. Clinical trials reveal that 12 weeks of moderate exercise increases fecal Coprococcus and Blautia abundance, correlating with improved 5-HT bioavailability and reduced depression scores. Third, exercise normalizes HPA axis hyperactivity by reducing cortisol levels and restoring glucocorticoid receptor sensitivity. In rodent models, chronic stress-induced corticosterone elevation is reversed by probiotic supplementation (e.g., Lactobacillus), which enhances endocannabinoid signaling and hippocampal neurogenesis. Furthermore, exercise upregulates brain-derived neurotrophic factor (BDNF) via microbial metabolites like butyrate, promoting histone acetylation and synaptic plasticity. FMT experiments confirm that exercise-induced microbiota elevates prefrontal BDNF expression, reversing stress-induced neuronal atrophy. Fourth, exercise reshapes microbial metabolic crosstalk, diverting tryptophan metabolism toward 5-HT synthesis instead of neurotoxic kynurenine derivatives. Butyrate inhibits indoleamine 2,3-dioxygenase (IDO), a key enzyme in the kynurenine pathway linked to depression. Concurrently, exercise-induced Akkermansia enrichment enhances mucin production, fortifies the gut barrier, and reduces LPS-driven neuroinflammation. Collectively, these mechanisms underscore exercise as a potent modulator of the microbiota-gut-brain axis, offering a holistic approach to alleviating depression through microbial and neurophysiological synergy. Current evidence supports exercise as a potent adjunct therapy for depression, with personalized regimens (e.g., aerobic, resistance, or yoga) tailored to individual microbiota profiles. However, challenges remain in optimizing exercise prescriptions (intensity, duration, and type) and integrating them with probiotics, prebiotics, or FMT for synergistic effects. Future research should prioritize large-scale randomized controlled trials to validate causality, multi-omics approaches to decipher MGB axis dynamics, and mechanistic studies exploring microbial metabolites as therapeutic targets. The authors advocate for a paradigm shift toward microbiota-centric interventions, emphasizing the bidirectional relationship between physical activity and gut ecosystem resilience in mental health management. In conclusion, this review underscores exercise as a multifaceted modulator of the gut-brain axis, offering novel insights into non-pharmacological strategies for depression. By bridging microbial ecology, neuroimmunology, and exercise physiology, this work lays a foundation for precision medicine approaches targeting the gut microbiota to alleviate depressive disorders.
3.A case-control study on the association of Hashimoto’s thyroiditis and anti-thyroid antibodies with oral lichen planus
LIU Yuan ; CHEN Yan ; CONG Zhaoxia ; LI Yiming ; XUE Rui ; ZHAO Jin
Journal of Prevention and Treatment for Stomatological Diseases 2025;33(9):757-764
Objective:
This study aims to explore the association between oral lichen planus (OLP) and Hashimoto’s thyroiditis (HT) and its anti-thyroid antibodies to provide clinical evidence for thyroid disease screening in patients with OLP.
Methods:
This study was approved by the institutional ethics committee. A total of 125 clinically and histopathologically confirmed patients with OLP were enrolled as the case group, and they were matched with 125 non-OLP controls based on sex and age. Demographic data (gender, age, lesion type, and disease duration) were collected from both groups. Serum levels of thyroid peroxidase antibodies (TPOAb) and thyroglobulin antibodies (TgAb) were measured to analyze their associations with sex, age, lesion type, and disease duration in patients with OLP.
Result:
The prevalence of HT in patients with OLP was 31.20%, significantly higher than that in the control group (9.60%) (χ2=18.504, P<0.001). The prevalence of HT in female patients with OLP (39.13%) was significantly higher than that in male patients (9.09%)(χ2=10.93,P<0.001). The positivity rate of thyroid peroxidase antibodies (TPOAb) in patients with OLP (17.6%) was significantly higher than in the control group (4.0%) (χ2=10.989, P<0.001). The TPOAb positivity rate was significantly higher in female patients (22.83%) than in male patients (3.03%) (χ2=5.210, P=0.014). There was no statistically significant difference in the positivity rate of TgAb between patients with OLP (7.2%) and the control group (3.2%) (P>0.05). Patients with erosive lesions had a significantly higher TPOAb positivity rate (25.0%, 17/68) compared to those with non-erosive lesions (8.77%, 5/57), and the difference was statistically significant (χ2=4.831, P=0.028). Logistic regression analysis revealed that female patients with OLP had an 8.935-fold higher risk of being TPOAb positive compared to males (OR=8.935, 95%CI: 1.134-70.388, P=0.038). Patients with erosive OLP lesions had a 3.199-fold higher risk of TPOAb positivity compared to those with non-erosive lesions (OR=3.199, 95%CI: 1.064-9.618, P=0.038).
Conclusion
The prevalence of HT is higher in patients with OLP, with higher positivity rates of anti-thyroid antibodies observed in female patients and those with erosive OLP lesions. This suggests that thyroid disease screening should be incorporated into the clinical management of patients with OLP, especially for women and patients who present with erosive lesions.
4.Network Pharmacology and Experimental Verification Unraveled The Mechanism of Pachymic Acid in The Treatment of Neuroblastoma
Hang LIU ; Yu-Xin ZHU ; Si-Lin GUO ; Xin-Yun PAN ; Yuan-Jie XIE ; Si-Cong LIAO ; Xin-Wen DAI ; Ping SHEN ; Yu-Bo XIAO
Progress in Biochemistry and Biophysics 2025;52(9):2376-2392
ObjectiveTraditional Chinese medicine (TCM) constitutes a valuable cultural heritage and an important source of antitumor compounds. Poria (Poria cocos (Schw.) Wolf), the dried sclerotium of a polyporaceae fungus, was first documented in Shennong’s Classic of Materia Medica and has been used therapeutically and dietarily in China for millennia. Traditionally recognized for its diuretic, spleen-tonifying, and sedative properties, modern pharmacological studies confirm that Poria exhibits antioxidant, anti-inflammatory, antibacterial, and antitumor activities. Pachymic acid (PA; a triterpenoid with the chemical structure 3β-acetyloxy-16α-hydroxy-lanosta-8,24(31)-dien-21-oic acid), isolated from Poria, is a principal bioactive constituent. Emerging evidence indicates PA exerts antitumor effects through multiple mechanisms, though these remain incompletely characterized. Neuroblastoma (NB), a highly malignant pediatric extracranial solid tumor accounting for 15% of childhood cancer deaths, urgently requires safer therapeutics due to the limitations of current treatments. Although PA shows multi-mechanistic antitumor potential, its efficacy against NB remains uncharacterized. This study systematically investigated the potential molecular targets and mechanisms underlying the anti-NB effects of PA by integrating network pharmacology-based target prediction with experimental validation of multi-target interactions through molecular docking, dynamic simulations, and in vitro assays, aimed to establish a novel perspective on PA’s antitumor activity and explore its potential clinical implications for NB treatment by integrating computational predictions with biological assays. MethodsThis study employed network pharmacology to identify potential targets of PA in NB, followed by validation using molecular docking, molecular dynamics (MD) simulations, MM/PBSA free energy analysis, RT-qPCR and Western blot experiments. Network pharmacology analysis included target screening via TCMSP, GeneCards, DisGeNET, SwissTargetPrediction, SuperPred, and PharmMapper. Subsequently, potential targets were predicted by intersecting the results from these databases via Venn analysis. Following target prediction, topological analysis was performed to identify key targets using Cytoscape software. Molecular docking was conducted using AutoDock Vina, with the binding pocket defined based on crystal structures. MD simulations were performed for 100 ns using GROMACS, and RMSD, RMSF, SASA, and hydrogen bonding dynamics were analyzed. MM/PBSA calculations were carried out to estimate the binding free energy of each protein-ligand complex. In vitro validation included RT-qPCR and Western blot, with GAPDH used as an internal control. ResultsThe CCK-8 assay demonstrated a concentration-dependent inhibitory effect of PA on NB cell viability. GO analysis suggested that the anti-NB activity of PA might involve cellular response to chemical stress, vesicle lumen, and protein tyrosine kinase activity. KEGG pathway enrichment analysis suggested that the anti-NB activity of PA might involve the PI3K/AKT, MAPK, and Ras signaling pathways. Molecular docking and MD simulations revealed stable binding interactions between PA and the core target proteins AKT1, EGFR, SRC, and HSP90AA1. RT-qPCR and Western blot analyses further confirmed that PA treatment significantly decreased the mRNA and protein expression of AKT1, EGFR, and SRC while increasing the HSP90AA1 mRNA and protein levels. ConclusionIt was suggested that PA may exert its anti-NB effects by inhibiting AKT1, EGFR, and SRC expression, potentially modulating the PI3K/AKT signaling pathway. These findings provide crucial evidence supporting PA’s development as a therapeutic candidate for NB.
5.Centrifuge overload simulation method for post stall super maneuvering flights
Yi WANG ; Cong WANG ; Ming-hao YANG ; Zhao JIN ; Li-hui ZHANG ; Yuan-jing ZHENG
Chinese Medical Equipment Journal 2025;46(7):21-26
Objective To propose a centrifuge overload simulation method for post stall super manueuvering flights to conduct the pilot centrifuge training during post stall super maneuvering flights.Methods Firstly,the independent active disturbance rejection control was designed in the longitudinal,transverse and heading channels to achieve closed-loop control of the aircraft at high angles of attack with thrust vector control technology.Secondly,a method for establishing control command for the three-axis centrifuge with the main arm rotation,cabin roll and cabin pitch was put forward based on the relationship between the pilot overload and the centrifuge control information.Finally,a simulation model was constructed based on the cobra maneuver to carry out digital simulation experiments.Results The method proposed effectively extracted overload information under super maneuvering flight conditions,then the centrifuge control commands could be determined accordingly to enable corresponding overload trainings with the centrifuge.Conclusion The proposed method facilitates the improvement of pilots'flight maneuvering performance in post stall super maneuvering flights under sustained high overload conditions.[Chinese Medical Equipment Journal,2025,46(7):21-26]
6.A Study on the Impact of the Employee Medical Insurance Outpatient Mutual Assistance System on Medical Insurance Costs for Patients with Diabetes Mellitus
Meng'en CHEN ; Xiaoxi ZHANG ; Youshu YUAN ; Yan WANG ; Tianzhen CONG ; Haojia HOU ; Jingyu YANG ; Zhiwei WANG
Chinese Health Economics 2025;44(10):38-42
Objective:It aims to examine the effects of the employee medical insurance outpatient mutual assistance on medical insurance costs for patients with diabetes mellitus,offering insights for optimizing outpatient insurance policies and chronic disease management strategies.Methods:Outpatient cost settlement data of urban employees with diabetes mellitus in Lanzhou from 2022 to 2023 was collected.Univariate analysis and interrupted time-series models were used to compare relevant medical insurance cost indicators before and after the reform.Results:The inpatient data of 765 730 diabetes mellitus patients were included in the study,and male patients account for 62.67%.After the reform,average per-visit pooling fund expenditure,average per-visit individual payment expenditures,average per-visit personal account expenditure,average per-visit eligible expense amount,average per-visit total fund payment,and the average per-visit proportion of basic medical pooling payments were decreased(P<0.05).Moreover,average per-visit pooling fund expenditure,average per-visit individual account expenditure,average per-visit cash payment,average per-visit eligible expense amount,average per-visit total fund payment,and the average per-visit proportion of basic medical pooling payments showed a notable declining trend post-reform(P<0.05).In contrast,the per-visit fully out-of-pocket expenditure exhibited no significant change before and after the reform(P>0.05).Conclusion:The reform of the employee medical insurance outpatient mutual assistance system has alleviated the economic burden of disease for diabetic patients and improved the efficiency of medical insurance fund utilization,but it reduced the proportion of basic medical pooling payments.It is recommended to continuously refine the outpatient medical insurance payment system,strengthen supervision of medical expenses and service quality,and balance patient benefits with fund pressure to enhance chronic disease outpatient benefits.
7.Liraglutide may alleviate acetaminophen-induced liver injury by enhancing autophagy
Guo-jing XING ; Wen-bin LI ; Long-long LUO ; Li-fei WANG ; Yuan DENG ; Zhen WANG ; Zhao-jie ZHANG ; Xiao-hui YU ; Jiu-cong ZHANG
Chinese Pharmacological Bulletin 2025;41(10):1867-1875
Aim To investigate the protective effect of liraglutide(LIRA)on acetaminophen(APAP)-in-duced hepatotoxicity at the in vivo level and to reveal the underlying mechanism.Methods Forty SPF grade male C57BL/6J mice were randomly divided into the Control,LIRA(200 μg·kg-1),APAP(500 mg·kg-1),LIRA+APAP,LIRA+APAP+3-methylade-nine(3-MA,30 mg·kg-1)groups,with eight mice in each group.The mice were administered for three con-secutive days,and the materials were taken after 24 h.The general condition and body weight of mice in each group were recorded,and liver morphology was ob-served.Serum ALT and AST levels,as well as SOD ac-tivity,MDA,and GSH content in liver homogenates,were measured using biochemical assay kits.The levels of inflammatory cytokines IL-6,TNF-α,and IL-1β in serum were detected by ELISA.Liver pathological changes were assessed by HE staining,while mitochon-drial and autophagosome structures in liver tissues were observed using transmission electron microscopy.The number of PCNA-positive cells in liver tissues was e-valuated using immunohistochemical staining.The pro-tein expression levels of LC3Ⅱ,p62,Bax,Bcl-2,PC-NA,and CyclinD1 in liver tissues were determined by Western blot.Results LIRA pretreatment can im-prove the general condition of mice with acetamino-phen-induced liver injury(AILI),reduce serum ALT and AST levels,and effectively ameliorate the appear-ance and morphology of the liver as well as the patho-logical damage to liver tissue.Simultaneously,the lev-els of inflammatory cytokines IL-6,TNF-α,and IL-1βare significantly decreased;SOD activity and GSH con-tent are significantly increased,while MDA content is significantly reduced.Transmission electron microsco-py observations reveal the presence of numerous auto-phagosomes in the cytoplasm of liver tissue.Immuno-histochemical staining results indicate a significant in-crease in the number of PCNA-positive cells.Further-more,the expression of LC3Ⅱ,Bcl-2,PCNA,and Cy-clinD1 proteins in liver tissue is significantly upregulat-ed,while the expression of p62 and Bax proteins is significantly downregulated.However,after interven-tion with the autophagy inhibitor 3-MA,the aforemen-tioned protective effects of LIRA are significantly.Conclusions LIRA pretreatment can significantly im-prove liver injury in AILI mice.Its protective mecha-nism may be related to enhancing autophagy in hepato-cytes,thereby reducing oxidative stress,inflammatory response and apoptosis in liver of AILI mice.
8.A Study on the Impact of the Employee Medical Insurance Outpatient Mutual Assistance System on Medical Insurance Costs for Patients with Diabetes Mellitus
Meng'en CHEN ; Xiaoxi ZHANG ; Youshu YUAN ; Yan WANG ; Tianzhen CONG ; Haojia HOU ; Jingyu YANG ; Zhiwei WANG
Chinese Health Economics 2025;44(10):38-42
Objective:It aims to examine the effects of the employee medical insurance outpatient mutual assistance on medical insurance costs for patients with diabetes mellitus,offering insights for optimizing outpatient insurance policies and chronic disease management strategies.Methods:Outpatient cost settlement data of urban employees with diabetes mellitus in Lanzhou from 2022 to 2023 was collected.Univariate analysis and interrupted time-series models were used to compare relevant medical insurance cost indicators before and after the reform.Results:The inpatient data of 765 730 diabetes mellitus patients were included in the study,and male patients account for 62.67%.After the reform,average per-visit pooling fund expenditure,average per-visit individual payment expenditures,average per-visit personal account expenditure,average per-visit eligible expense amount,average per-visit total fund payment,and the average per-visit proportion of basic medical pooling payments were decreased(P<0.05).Moreover,average per-visit pooling fund expenditure,average per-visit individual account expenditure,average per-visit cash payment,average per-visit eligible expense amount,average per-visit total fund payment,and the average per-visit proportion of basic medical pooling payments showed a notable declining trend post-reform(P<0.05).In contrast,the per-visit fully out-of-pocket expenditure exhibited no significant change before and after the reform(P>0.05).Conclusion:The reform of the employee medical insurance outpatient mutual assistance system has alleviated the economic burden of disease for diabetic patients and improved the efficiency of medical insurance fund utilization,but it reduced the proportion of basic medical pooling payments.It is recommended to continuously refine the outpatient medical insurance payment system,strengthen supervision of medical expenses and service quality,and balance patient benefits with fund pressure to enhance chronic disease outpatient benefits.
9.Structural Design and Experimental Study of a New Aerodynamic Electric Hook
Cao LIU ; Junwei HUANG ; Haidong LIAO ; Jiale YUAN ; Yang XIE ; Jiafeng LIU ; Yong YING ; Xiangtai ZENG ; Cong LIAO
Chinese Journal of Minimally Invasive Surgery 2025;25(10):628-635
Objective To investigate the safety parameters of the air-powered electrocautery hook and its advantages in laparoscopic surgery.Methods In pressure trauma experiments,21 healthy New Zealand White Rabbits were randomly divided into three groups.In each group,three sites(liver,intestine,and kidney)were selected from each rabbit,and the air-powered electrocautery hook was used under laparoscopy to apply pressure and time gradients in a cross-combination manner.The three groups of experimental rabbits were dissected at three time points:immediately after application,3 d post-application,and 7 d post-application.Pathological sections were prepared from the corresponding treated sites,and the extent of injury was assessed.In rabbit renal capsule removal experiment,another 20 healthy New Zealand White Rabbits were randomly divided into 2 groups.Renal capsule removal was performed by using an air-powered electrosurgical hook and a conventional electrosurgical hook,respectively,to compare the two groups in terms of surgical time,intraoperative bleeding volume,intraoperative complications,and the number of times of wiping speculum.Results In pressure trauma experiment,except for the intestinal tract at 3 seconds(P=0.060),the histopathological scores under 0.3 MPa pressure were significantly higher than those under 0.1 MPa(P<0.05)and 0.2 MPa(P<0.05)in all the tissues.In the tissue sampling groups at 3 d and 7 d post-surgery,no tissue damage was observed in any tissue at any time point under 0.1 MPa pressure.In rabbit renal capsule removal experiment,the aerodynamic electrocautery group had less intraoperative bleeding volume than the conventional electrocautery group[(2.9±0.5)ml vs.(3.4±0.5)ml,t=-2.280,P=0.035].There were no significant differences between the two groups in terms of surgical time,intraoperative complication rates,and the number of times of wiping speculum(P>0.05).Conclusions The safe pressure range for using the air-powered electrosurgical hook on the surfaces of the kidney and intestinal tract is within 0.2 MPa.Within the safe pressure range,blowing on tissue for 6 seconds or less is relatively safe.Using the air-powered electrosurgical hook in surgeries requiring the separation of loose connective tissue can reduce intraoperative bleeding.
10.Heterologous Expression,Purification and Enzymatic Characterization of Xylitol Dehydrogenase from the Thermophilic Fungus Talaromyces emersonii
Er MENG ; Cong QU ; Ke YI ; Hui-Min LI ; Xin-Yi DUAN ; Zhe-Yuan ZHANG ; Shao-Long HE ; Yu-Tao LUO ; Lei WU ; Dong-Yi ZHANG ; Chang-Jun LIU
Chinese Journal of Biochemistry and Molecular Biology 2025;41(7):1007-1018
The xylitol dehydrogenase(XDH)is a crucial enzyme involved in the xylose utilization in pentose-catabolizing yeasts and fungi.In addition to producing xylulose,XDH can also be employed to develop a biosensor for monitoring xylitol concentration.In this study,the gene encoding the thermophilic fungus Talaromyces emersonii XDH(TeXDH)was heterologously expressed in Escherichia coli BL21(DE3)at 16 ℃ in the soluble form.Recombinant TeXDH with high purity was purified by using a Ni-NTA affinity column.Size-exclusion chromatography and SDS-PAGE analysis demonstrated that the puri-fied recombinant TeXDH exists as a native trimer with a molecular mass of approximately 116 kD,and is composed of three identical subunits,each with a molecular weight of around 39 kD.The TeXDH strictly preferred NAD+as a coenzyme to NADP+.The optimal temperature and pH of the TeXDH were 40 ℃and 10.0,respectively.After EDTA treatment,the enzyme activity of TeXDH decreased to 43.26%of the initial enzyme activity,while the divalent metal ions Mg2+or Ca2+could recover the enzyme activity of TeXDH,reaching 103.32%and 110.69%of the initial enzyme activity,respectively,making them the optimal divalent metal ion cofactors for TeXDH enzyme.However,the divalent metal ions of Mn2+,Ni2+,Cu2+,Zn2+,Co2+,and Cd2+significantly inhibited the activity of TeXDH.ICP-MS and molecular doc-king studies revealed that 1 mol/L of TeXDH bound 2 mol/L Zn2+ions and 1 mol/L Mg2+ion.Further-more,TeXDH exhibited a high specificity for xylitol,laying the foundation for the development of future xylitol biosensors.


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