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1.
Heliyon ; 10(10): e30315, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38765036

RESUMEN

In this study, bibliometric analysis was carried out to comprehend the global research trends, hotspots, scientific frontiers, and output characteristics of the links between dendritic cells (DCs) and allergic diseases from 2004 to 2023. Publications and their recorded information were retrieved from the Web of Science Core Collection (WoSCC). VOSviewer and Citespace were used to visualize the hotspots and trends of research area. ChemBio 3D, Autodock tools, and Discovery Studio were used to visualize the molecular docking results of hotspots. A total of 4861 articles were retrieved. The number of publications (Np) was in a high and stable state. Years 2011 and 2017 were two peaks in Np. The largest contributor in terms of publications, scholars, and affiliations was the USA. The paper published in NATURE MEDICINE (IF: 82.9) and written by Trompette, A in 2006 had the highest global citation score (GCS). Keywords, such as "asthma," "t-cells," "inflammation," "expression," "atopic dermatitis," "food allergy," "gut microbiota," "murine model," and "cytokines related to immunity" appeared the most frequently. Most of the binding free energy of the key active components of Saposhnikovia divaricata docked with toll-like receptor proteins well. This bibliometric study aimed to help better comprehend the present state and make decisions from a macro viewpoint.

2.
J Bone Oncol ; 46: 100604, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38765702

RESUMEN

Osteosarcoma (OS), a malignant tumor, originates from the bone marrow. Currently, treatment for OS remains limited, making it urgent to understand the immune response in the tumor microenvironment of patients with OS. A comprehensive bioinformatics analysis was performed, including cell clustering subgroups, differential expression genes screening, proposed temporal order, and genomic variant analysis on single-cell RNA-sequencing data, from ten pre-chemotherapy patients and eleven post-chemotherapy patients. Subsequently, we analyzed the differentiation trajectories of osteoblasts, osteoclasts, fibroblasts, myeloid cells, and tumor-infiltrating lymphocytes (TILs) in detail to compare the changes in cell proportions and differential genes pre- and post-chemotherapy. The nine cell types were identified, including fibroblasts, myeloid cells, osteoblasts, TILs, osteoclasts, proliferative osteoblasts, pericytes, endothelial cells, and B cells. Post-chemotherapy treatment, the proportions of myeloid cells and TILs in OS were declined, while the number of osteoblasts was elevated. Besides, a decrease was observed in CD74, FTL, FTH1, MT1X and MT2A, and an increase in PTN, COL3A1, COL1A1, IGFBP7 and FN1. Meanwhile, EMT, DNA repair, G2M checkpoint, and E2F targets were highly enriched post-chemotherapy. Furthermore, there was a down-regulation in the proportions of CD14 monocytes, Tregs, NK cells and CD1C-/CD141-DCs, while an up-regulation was observed in the proportions of SELENOP macrophages, IL7R macrophages, COL1A1 macrophages, CD1C DCs, CD4+ T cells and CD8+ T cells. Overall, these findings revealed changes in the tumor microenvironment of OS post-chemotherapy treatment, providing a new direction for investigating OS treatment.

3.
Front Vet Sci ; 11: 1375852, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38756509

RESUMEN

Jingmen tick virus (JMTV) is a newly identified segmented flavivirus that has been recognized in multiple hosts, such as humans, buffalos, bats, rodents, mosquitos and ticks. Various clinical cases and studies manifested that JMTV is a true arbovirus with wide host spectrum and showed potential threats toward public health. JMTV has been reported in multiple countries in Asia, Europe, Africa, and America. Moreover, wild boars serve as an important intermediary between humans and the wild ecological system. In China, it has been reported in nine provinces, while the prevalence and the distribution of JMTV in most regions including Jiangxi Province are still unknown. Thus, to profile the distribution of JMTV in Jiangxi Province, an epidemiological investigation was carried out from 2020 to 2022. In current study, 66 ticks were collected from 17 wild boars in Jiangxi Province. The results showed that 12 out of 66 ticks were JMTV positive, indicating JMTV is prevalent in ticks and boars in Jiangxi Province. The genome sequences of JMTV strain WY01 were sequenced to profile viral evolution of JMTV in China. Phylogenetic analysis divided JMTV strains into two genotypes, Group I and Group II. WY01 belongs to Group II and it shares the closest evolutionary relationship with the Japan strains rather than the strains from neighboring provinces in China suggesting that JMTV might have complex transmission routes. Overall, current study, for the first time, reported that JMTV is prevalent in Jiangxi Province and provided additional information concerning JMTV distribution and evolution in China.

4.
Technol Health Care ; 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38759044

RESUMEN

BACKGROUND: Physical activity (PA) holds profound implications for the holistic development of college students. However, students with chronic diseases or physical disabilities experience significantly limited PA during adaptive sports. OBJECTIVE: This study aims to investigate the relationship between physical activity and Functional Movement Screening (FMS) among university students who participate in the adaptive physical course. METHODS: 36 university students (from the adaptive physical course) completed the International Physical Activity Questionnaire-Long Form (IPAQ-L). Body measurements and FMS were assessed. Correlation analysis and t-tests were used to determine relationships and differences between various indicators. A two-way analysis of variance was used to investigate potential variations in FMS scores based on gender and weight status. RESULTS: The results show that gender, PA, and BMI significantly influence FMS scores in students participating in adaptive physical courses. FMS score is significantly negatively correlated with BMI and significantly positively correlated with PA. The FMS score for males, as well as the scores for Trunk Stability Push-Up and Rotary Stability, are significantly higher than those for females. CONCLUSION: University students in adaptive physical courses can benefit from increased PA and FMS scores. Improving functional movement and enhancing physical activity are crucial for promoting overall health in this population.

5.
Technol Health Care ; 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38759071

RESUMEN

BACKGROUND: Shoes upper has been shown to affect the shoe microclimate (temperature and humidity). However, the existing data on the correlation between the microclimate inside footwear and the body's physical factors is still quite limited. OBJECTIVE: This study examined whether shoes air permeability would influence foot microclimate and spatial characteristics of lower limb and body. METHODS: Twelve recreational male habitual runners were instructed to finish an 80 min experimental protocol, wearing two running shoes with different air permeability. Participants wearing CLOSED upper structure shoe exhibited higher in-shoe temperature and relative humidity. RESULTS: Although there was no significant difference, shank temperature and metabolism in OPEN upper structure shoes were lower. CONCLUSIONS: This indicates that the air permeability of shoes can modify the microclimate of the feet, potentially affecting the lower limb temperature. This study provides relevant information for the design and evaluation of footwear.

6.
Anal Chem ; 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773697

RESUMEN

Sensitive identification and effective inactivation of the virus are paramount for the early diagnosis and treatment of viral infections to prevent the risk of secondary transmission of viruses in the environment. Herein, we developed a novel two-step fluorescence immunoassay using antibody/streptavidin dual-labeled polystyrene nanobeads and biotin-labeled G-quadruplex/hemin DNAzymes with peroxidase-mimicking activity for sensitive quantitation and efficient inactivation of living Zika virus (ZIKV). The dual-labeled nanobeads can specifically bind ZIKV through E protein targeting and simultaneously accumulate DNAzymes, leading to the catalytic oxidation of Amplex Red indicators and generation of intensified aggregation-induced emission fluorescence signals, with a detection limit down to 66.3 PFU/mL and 100% accuracy. Furthermore, robust reactive oxygen species generated in situ by oxidized Amplex Red upon irradiation can completely kill the virus. This sensitive and efficient detection-inactivation integrated system will expand the viral diagnostic tools and reduce the risk of virus transmission in the environment.

7.
Org Biomol Chem ; 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38771218

RESUMEN

A palladium-catalyzed decarboxylative asymmetric [4 + 2] annulation of methyleneindolinones with a zwitterionic oxo-1,4-dipole intermediate was successfully developed to access spirocyclic oxindoles bearing two vicinal stereocenters in good yields with high diastereoselectivities and enantioselectivities. This strategy features a broad substrate scope (28 examples), allowing for efficient scale-up. Further selective transformation of the product and preliminary mechanistic studies were conducted.

8.
Int J Ophthalmol ; 17(3): 528-536, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38721515

RESUMEN

AIM: To evaluate the effectiveness and safety of early lens extraction during pars plana vitrectomy (PPV) for proliferative diabetic retinopathy (PDR) compared to those of PPV with subsequent cataract surgery. METHODS: This multicenter randomized controlled trial was conducted in three Chinese hospitals on patients with PDR, aged >45y, with mild cataracts. The participants were randomly assigned to the combined (PPV combined with simultaneously cataract surgery, i.e., phacovitrectomy) or subsequent (PPV with subsequent cataract surgery 6mo later) group and followed up for 12mo. The primary outcome was the change in best-corrected visual acuity (BCVA) from baseline to 6mo, and the secondary outcomes included complication rates and medical expenses. RESULTS: In total, 129 patients with PDR were recruited and equally randomized (66 and 63 in the combined and subsequent groups respectively). The change in BCVA in the combined group [mean, 36.90 letters; 95% confidence interval (CI), 30.35-43.45] was significantly better (adjusted difference, 16.43; 95%CI, 8.77-24.08; P<0.001) than in the subsequent group (mean, 22.40 letters; 95%CI, 15.55-29.24) 6mo after the PPV, with no significant difference between the two groups at 12mo. The overall surgical risk of two sequential surgeries was significantly higher than that of the combined surgery for neovascular glaucoma (17.65% vs 3.77%, P=0.005). No significant differences were found in the photocoagulation spots, surgical time, and economic expenses between two groups. In the subsequent group, the duration of work incapacity (22.54±9.11d) was significantly longer (P<0.001) than that of the combined group (12.44±6.48d). CONCLUSION: PDR patients aged over 45y with mild cataract can also benefit from early lens extraction during PPV with gratifying effectiveness, safety and convenience, compared to sequential surgeries.

9.
IUBMB Life ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38721892

RESUMEN

Low back pain is a common clinical symptom of intervertebral disc degeneration (IVDD), which seriously affects the quality of life of the patients. The abnormal apoptosis and senescence of nucleus pulposus cells (NPCs) play important roles in the pathogenesis of IVDD. PHLDA2 is an imprinted gene related to cell apoptosis and tumour progression. However, its role in NPC degeneration is not yet clear. Therefore, this study was set to explore the effects of PHLDA2 on NPC senescence and apoptosis and the underlying mechanisms. The expression of PHLDA2 was examined in human nucleus pulposus (NP) tissues and NPCs. Immunohistochemical staining, magnetic resonance imaging imaging and western blot were performed to evaluate the phenotypes of intervertebral discs. Senescence and apoptosis of NPCs were assessed by SA-ß-galactosidase, flow cytometry and western blot. Mitochondrial function was investigated by JC-1 staining and transmission electron microscopy. It was found that the expression level of PHLDA2 was abnormally elevated in degenerated human NP tissues and NPCs. Furthermore, knockdown of PHLDA2 can significantly inhibit senescence and apoptosis of NPCs, whereas overexpression of PHLDA2 can reverse senescence and apoptosis of NPCs in vitro. In vivo experiment further confirmed that PHLDA2 knockdown could alleviate IVDD in rats. Knockdown of PHLDA2 could also reverse senescence and apoptosis in IL-1ß-treated NPCs. JC-1 staining indicated PHLDA2's knockdown impaired disruption of the mitochondrial membrane potential and also ameliorated superstructural destruction of NPCs as showed by transmission electron microscopy. Finally, we found the PHLDA2 knockdown promoted Collagen-II expression and suppressed MMP3 expression in NPCs by repressing wnt/ß-catenin pathway. In conclusion, the results of the present study showed that PHLDA2 promotes IL-1ß-induced apoptosis and senescence of NP cells via mitochondrial route by activating the Wnt/ß-catenin pathway, and suggested that therapy targeting PHLDA2 may provide valuable insights into possible IVDD therapies.

11.
Materials (Basel) ; 17(9)2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38730741

RESUMEN

In this study, an effective numerical model was developed for the calculation of the deformation of laser-welded 3 mm 304L stainless steel plates with different gaps (0.2 mm, 0.5 mm, and 1.0 mm). The welding deformation would become larger when the welding gaps increased, and the largest deformation values along the Z direction, of 4 mm, were produced when the gap value was 1.0 mm. A larger plastic strain region was generated in the location near the weld seam, since higher plastic deformation had occurred. In addition, the tensile stress model was also applied at the plastic strain zone and demonstrated that a larger welding gap led to a wider residual stress area. Based on the above results, inherent deformations for butt and corner joints were calculated according to inherent strain theory, and the welding formation for the complex structure was calculated with different gaps. The numerical results demonstrated that a larger deformation was also produced with a larger welding gap and that it could reach the highest value of 10.1 mm. This proves that a smaller welding gap should be adopted during the laser welding of complex structures to avoid excessive welding deformation.

12.
Transl Lung Cancer Res ; 13(4): 849-860, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38736498

RESUMEN

Background: Resectable non-small cell lung cancer (NSCLC) patients have a high risk of recurrence. Multiple randomized controlled trials (RCTs) have shown that neoadjuvant chemo-immunotherapy brings new hope for these patients. The study aims to evaluate the safety, surgery-related outcomes and oncological outcomes for neoadjuvant chemo-immunotherapy in real-world setting with a large sample size and long-term follow-up. Methods: Patients with clinical stage IB-IIIB NSCLC who received neoadjuvant chemo-immunotherapy at two Chinese institutions were included in this retrospective cohort study. Surgical and oncological outcomes of the enrolled NSCLC patients were collected and analyzed. Results: There were 158 patients identified, of which 124 (78.5%) were at stage IIIA-IIIB and the remaining 34 (21.5%) were at stage IB-IIB. Forty-one patients (25.9%) received two cycles of neoadjuvant treatment, 80 (50.6%) had three cycles, and 37 (23.4%) had four cycles. Twenty-four patients (15.2%) experienced grade 3 or worse immune-related adverse events. The median interval time between the last neoadjuvant therapy and surgery was 37 [interquartile range (IQR), 31-43] days. Fifty-eight out of 96 (60.4%) central NSCLC patients who were expected to undergo complex surgery had the scope or the difficulty of operation reduced. Ninety-five (60.1%) patients achieved major pathologic response (MPR), including 62 (39.2%) patients with pathologic complete response (pCR). Multivariate regression analysis showed that no clinical factor other than programmed death-ligand 1 (PD-L1) expression was predictive of the pathological response. The median follow-up time from diagnosis was 27.1 months. MPR and pCR were significantly associated with improved progression-free survival (PFS) and overall survival (OS). Neither stage nor PD-L1 expression was significantly associated with long-term survival. Conclusions: The neoadjuvant chemo-immunotherapy is a feasible strategy for NSCLC with a favorable rate of pCR/MPR, modified resection and 2-year survival. No clinical factor other than PD-L1 expression was predictive of the pathological response. pCR/MPR may be effective surrogate endpoint for survival in NSCLC patients who received neoadjuvant chemo-immunotherapy.

13.
Cell Biosci ; 14(1): 58, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38720328

RESUMEN

The cyclic guanosine monophosphate (GMP)-adenosine monophosphate (AMP) synthase-stimulator of interferon genes (cGAS-STING) signaling pathway, an important component of the innate immune system, is involved in the development of several diseases. Ectopic DNA-induced inflammatory responses are involved in several pathological processes. Repeated damage to tissues and metabolic organelles releases a large number of damage-associated molecular patterns (mitochondrial DNA, nuclear DNA, and exogenous DNA). The DNA fragments released into the cytoplasm are sensed by the sensor cGAS to initiate immune responses through the bridging protein STING. Many recent studies have revealed a regulatory role of the cGAS-STING signaling pathway in cardiovascular diseases (CVDs) such as myocardial infarction, heart failure, atherosclerosis, and aortic dissection/aneurysm. Furthermore, increasing evidence suggests that inhibiting the cGAS-STING signaling pathway can significantly inhibit myocardial hypertrophy and inflammatory cell infiltration. Therefore, this review is intended to identify risk factors for activating the cGAS-STING pathway to reduce risks and to simultaneously further elucidate the biological function of this pathway in the cardiovascular field, as well as its potential as a therapeutic target.

14.
Hortic Res ; 11(5): uhae070, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38725459

RESUMEN

Citric acid (CA) plays a crucial role as a fruit flavor enhancer and serves as a mediator in multiple metabolic pathways in tomato fruit development. Understanding factors influencing CA metabolism is essential for enhancing fruit flavor and CA-mediated biological processes. The accumulation of CA, however, is influenced by a complex interplay of genetic and environmental factors, leading to challenges in accurately predicting and regulating its levels. In this study, we conducted a genome-wide association study (GWAS) on CA, employing six landmark models based on genome-wide variations including structural variants, insertions and deletions, and single nucleotide polymorphisms. The identification of 11 high-confidence candidate genes was further facilitated by leveraging linkage disequilibrium and causal variants associated with CA. The transcriptome data from candidate genes were examined, revealing higher correlations between the expression of certain candidate genes and changes in CA metabolism. Three CA-associated genes exerted a positive regulatory effect on CA accumulation, while the remaining genes exhibited negative impacts based on gene cluster and correlation analyses. The CA content of tomatoes is primarily influenced by improvement sweeps with minimal influence from domestication sweeps in the long-term breeding history, as evidenced by population differentiation and variants distribution. The presence of various causal variants within candidate genes is implicated in the heterogeneity of CA content observed among the tomato accessions. This observation suggests a potential correlation between the number of alternative alleles and CA content. This study offers significant function-based markers that can be utilized in marker-assisted breeding, thereby enhancing their value and applicability.

15.
Int J Biol Sci ; 20(7): 2727-2747, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38725857

RESUMEN

Phenotypic switching (from contractile to synthetic) of vascular smooth muscle cells (VSMCs) is essential in the progression of atherosclerosis. The damaged endothelium in the atherosclerotic artery exposes VSMCs to increased interstitial fluid shear stress (IFSS). However, the precise mechanisms by which increased IFSS influences VSMCs phenotypic switching are unrevealed. Here, we employed advanced numerical simulations to calculate IFSS values accurately based on parameters acquired from patient samples. We then carefully investigated the phenotypic switching and extracellular vesicles (EVs) secretion of VSMCs under various IFSS conditions. By employing a comprehensive set of approaches, we found that VSMCs exhibited synthetic phenotype upon atherosclerotic IFSS. This synthetic phenotype is the upstream regulator for the enhanced secretion of pro-calcified EVs. Mechanistically, as a mechanotransducer, the epidermal growth factor receptor (EGFR) initiates the flow-based mechanical cues to MAPK signaling pathway, facilitating the nuclear accumulation of the transcription factor krüppel-like factor 5 (KLF5). Furthermore, pharmacological inhibiting either EGFR or MAPK signaling pathway blocks the nuclear accumulation of KLF5 and finally results in the maintenance of contractile VSMCs even under increased IFSS stimulation. Collectively, targeting this signaling pathway holds potential as a novel therapeutic strategy to inhibit VSMCs phenotypic switching and mitigate the progression of atherosclerosis.


Asunto(s)
Receptores ErbB , Vesículas Extracelulares , Factores de Transcripción de Tipo Kruppel , Músculo Liso Vascular , Miocitos del Músculo Liso , Estrés Mecánico , Vesículas Extracelulares/metabolismo , Receptores ErbB/metabolismo , Factores de Transcripción de Tipo Kruppel/metabolismo , Factores de Transcripción de Tipo Kruppel/genética , Humanos , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Líquido Extracelular/metabolismo , Fenotipo , Animales , Aterosclerosis/metabolismo , Sistema de Señalización de MAP Quinasas , Transducción de Señal
16.
Front Endocrinol (Lausanne) ; 15: 1383772, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38715799

RESUMEN

Background: ASCVD is the primary cause of mortality in individuals with T2DM. A potential link between ASCVD and T2DM has been suggested, prompting further investigation. Methods: We utilized linear and multivariate logistic regression, Wilcoxon test, and Spearman's correlation toanalyzethe interrelation between ASCVD and T2DM in NHANES data from 2001-2018.The Gene Expression Omnibus (GEO) database and Weighted Gene Co-expression Network Analysis (WGCNA) wereconducted to identify co-expression networks between ASCVD and T2DM. Hub genes were identified using LASSO regression analysis and further validated in two additional cohorts. Bioinformatics methods were employed for gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, along with the prediction of candidate small molecules. Results: Our analysis of the NHANES dataset indicated a significant impact of blood glucose on lipid levels within diabetic cohort, suggesting that abnormal lipid metabolism is a critical factor in ASCVD development. Cross-phenotyping analysis revealed two pivotal genes, ABCC5 and WDR7, associated with both T2DM and ASCVD. Enrichment analyses demonstrated the intertwining of lipid metabolism in both conditions, encompassing adipocytokine signaling pathway, fatty acid degradation and metabolism, and the regulation of adipocyte lipolysis. Immune infiltration analysis underscored the involvement of immune processes in both diseases. Notably, RITA, ON-01910, doxercalciferol, and topiramate emerged as potential therapeutic agents for both T2DM and ASCVD, indicating their possible clinical significance. Conclusion: Our findings pinpoint ABCC5 and WDR7 as new target genes between T2DM and ASCVD, with RITA, ON-01910, doxercalciferol, and topiramate highlighted as promising therapeutic agents.


Asunto(s)
Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Femenino , Enfermedades Cardiovasculares/genética , Enfermedades Cardiovasculares/epidemiología , Masculino , Persona de Mediana Edad , Factores de Riesgo de Enfermedad Cardiaca , Metabolismo de los Lípidos/genética , Expresión Génica
17.
J Hazard Mater ; 472: 134520, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38718512

RESUMEN

Polyethylene (PE) microplastic, which is detected in various environmental media worldwide, also inevitably enters wastewater treatment plants, which may have an impact on anaerobic processes in wastewater treatment. In this work, the effect of PE microplastics on anaerobic sulfur transformation was explored. Experimental results showed that PE microplastics addition at 0.1%- 0.5% w/w promoted H2S production by 14.8%-27.4%. PE microplastics enhanced the release of soluble organic sulfur and inorganic sulfate, and promoted the bioprocesses of organosulfur compounds hydrolysis and sulfate reduction. Mechanism analysis showed that PE microplastics increased the content of electroactive components (e.g., protein and humic acids) contained in extracellular polymeric substances (EPS). In particular, PE microplastics increased the proportion and the dipole moment of α-helix, an important component involved in electron transfer contained in extracelluar protein, which provided more electron transfer sites and promoted the α-helix mediated electron transfer. These enhanced the direct electron transfer ability of EPSs, which might explain why PE microplastics facilitated the bioprocesses of organosulfur compounds hydrolysis and sulfate reduction. Correspondingly, metagenomic analysis revealed that PE microplastics increased the relative abundance of S2- producers (e.g., Desulfobacula and Desulfonema) and the relative abundance of functional genes involved in anaerobic sulfur transformation (e.g., PepD and cysD), which were beneficial to H2S production in anaerobic system.

18.
Biotechnol J ; 19(5): e2400178, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38719574

RESUMEN

Sucrose isomerase (SIase) catalyzes the hydrolysis and isomerization of sucrose into isomaltulose, a functional sugar extensively used in the food industry. However, the lack of safe and efficient heterologous expression systems for SIase has constrained its production and application. In this study, an engineered Bacillus subtilis strain for antibiotic-free SIase production was developed via a food-grade expression system. First, the B. subtilis strain TEA was modified through the CRISPR/Cas9 system, resulting in a mutant strain TEA4, which exhibited enhanced capabilities for recombinant protein expression. For efficient and safe production of SIase, different constitutive and inducible promoters were evaluated. The maltose-inducible promoter Poglv was found to have an extracellular SIase activity of 21.7 U mL-1 in engineered strain TEA4. Subsequent optimization of the culture medium further increased SIase activity to 26.4 U mL-1 during shake flask cultivation. Eventually, using the crude enzyme solution of the engineered strain in biotransformation reactions resulted in a high yield of isomaltulose under high concentrations sucrose, achieving a maximum yield of 83.1%. These findings demonstrated an engineered B. subtilis strain for antibiotic-free SIase production, paving the way for its scale-up industrial production and application.


Asunto(s)
Bacillus subtilis , Glucosiltransferasas , Isomaltosa , Proteínas Recombinantes , Sacarosa , Bacillus subtilis/genética , Bacillus subtilis/enzimología , Bacillus subtilis/metabolismo , Isomaltosa/metabolismo , Isomaltosa/análogos & derivados , Glucosiltransferasas/genética , Glucosiltransferasas/metabolismo , Sacarosa/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Ingeniería Metabólica/métodos , Regiones Promotoras Genéticas/genética , Sistemas CRISPR-Cas/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo
20.
Sci Bull (Beijing) ; 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38734586

RESUMEN

Ion channel activation upon ligand gating triggers a myriad of biological events and, therefore, evolution of ligand gating mechanism is of fundamental importance. TRPM2, a typical ancient ion channel, is activated by adenosine diphosphate ribose (ADPR) and calcium and its activation has evolved from a simple mode in invertebrates to a more complex one in vertebrates, but the evolutionary process is still unknown. Molecular evolutionary analysis of TRPM2s from more than 280 different animal species has revealed that, the C-terminal NUDT9-H domain has evolved from an enzyme to a ligand binding site for activation, while the N-terminal MHR domain maintains a conserved ligand binding site. Calcium gating pattern has also evolved, from one Ca2+-binding site as in sea anemones to three sites as in human. Importantly, we identified a new group represented by olTRPM2, which has a novel gating mode and fills the missing link of the channel gating evolution. We conclude that the TRPM2 ligand binding or activation mode evolved through at least three identifiable stages in the past billion years from simple to complicated and coordinated. Such findings benefit the evolutionary investigations of other channels and proteins.

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