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1.
Anal Chem ; 2024 Aug 02.
Article de Anglais | MEDLINE | ID: mdl-39094103

RÉSUMÉ

Fibrinolytic activity assay is particularly important for the detection, diagnosis, and treatment of cardiovascular disease and the development of fibrinolytic drugs. A novel efficacious strategy for real-time and label-free dynamic detection of fibrinolytic activity based on ordered porous layer interferometry (OPLI) was developed. Fibrin or a mixture of fibrin and plasminogen (Plg) was loaded into the highly ordered silica colloidal crystal (SCC) film scaffold to construct a fibrinolytic response interference layer to measure fibrinolytic activity with different mechanisms of action. Fibrinolytic enzyme-triggered fibrinolysis led to the migration of interference fringes in the interferogram, which could be represented by optical thickness changes (ΔOT) tracked in real time by the OPLI system. The morphology and optical property of the fibrinolytic response interference layer were characterized, and the Plg content in the fibrinolytic response interference layer and experimental parameters of the system were optimized. The method showed adequate sensitivity for the fibrinolytic activity of lumbrokinase and streptokinase, with wide linear ranges of 12-6000 and 10-2000 U/mL, respectively. Compared with the traditional fibrin plate method, it has a lower detection limit and higher linearity. The whole kinetic process of fibrinolysis by these two fibrinolytic drug models was recorded in real time, and the Michaelis constant and apparent kinetic parameters were calculated. Importantly, some other blood proteins were less interfering with this system, and it showed reliability in fibrin activity detection in real whole blood samples. This study established a better and more targeted research method of in vitro fibrinolysis and provided dynamic monitoring data for the analysis of fibrinolytic activity of whole blood.

2.
Int J Biol Macromol ; : 134649, 2024 Aug 09.
Article de Anglais | MEDLINE | ID: mdl-39128763

RÉSUMÉ

Immunoglobulin G (IgG) exhibits potent antiviral, antibacterial, and immunological activities. The digestion process and bioavailability of IgG are often a concern. Dietary hydrocolloids are crucial for regulating healthy digestion and the bioavailability of protein as functional components. Understanding the effects of dietary hydrocolloids on the digestive kinetics of IgG is requisite. Herein, the pepsin and trypsin digestion of IgG was investigated using ordered porous layer interferometry (OPLI). The real-time variation in the interference spectral shift reflected by OPLI can be converted into changes in the optical thickness (OT) to obtain a degradation kinetics curve. The impact of dietary hydrocolloids, including alginic acid sodium salt (ALG), polydextrose (PD), and konjac glucomannan (KG), on IgG degradation was evaluated using OPLI. The results demonstrated that ALG significantly inhibited the degradation of IgG by pepsin under acidic conditions, whereas the addition of PD increased the Michaelis-Menten constant for IgG degradation by trypsin. Notably, this dependence is not based on the hydrocolloid viscosity, but relies more on the electrical properties. The study enhances our understanding of how hydrocolloids affect IgG digestion and could provide valuable insights into preserving IgG activity and facilitating the development of oral drugs or health products related to IgG.

3.
BMC Vet Res ; 20(1): 356, 2024 Aug 10.
Article de Anglais | MEDLINE | ID: mdl-39127663

RÉSUMÉ

BACKGROUND: Klebsiella pneumoniae is a zoonotic opportunistic pathogen, and also one of the common pathogenic bacteria causing mink pneumonia. The aim of this study was to get a better understanding of the whole-genome of multi-drug resistant Klebsiella pneumoniae with K2 serotype in China. This study for the first time to analyze Gene Ontology (GO) enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment, resistance and virulence genes of Klebsiella pneumoniae in mink. RESULTS: The isolate was Klebsiella pneumoniae with serotype K2 and ST6189 by PCR method. The string test was positive and showed high mucus phenotype. There was one plasmid with IncFIB replicons in the genome. The virulence factors including capsule, lipopolysaccharide, adhesin, iron uptake system, urease, secretory system, regulatory gene (rcsA, rcsB), determinants of pili adhesion, enolase and magnesium ion absorption related genes. The strain was multi-drug resistant. A total of 26  resistance genes, including beta-lactam, aminoglycosides, tetracycline, fluoroquinolones, sulfonamides, amide alcohols, macrolides, rifampicin, fosfomycin, vancomycin, diaminopyrimidines and polymyxin. Multidrug-resistant efflux protein AcrA, AcrB, TolC, were predicted in the strain. CONCLUSION: It was the first to identify that serotype K2 K. pneumonia with ST6189 isolated from mink in China. The finding indicated that hypervirulent and multi-drug resistant K. pneumoniae was exist in Chinese mink. The whole-genome of K. pneumoniae isolates have importance in mink farming practice.


Sujet(s)
Multirésistance bactérienne aux médicaments , Klebsiella pneumoniae , Visons , Sérogroupe , Séquençage du génome entier , Animaux , Multirésistance bactérienne aux médicaments/génétique , Visons/microbiologie , Chine , Klebsiella pneumoniae/génétique , Klebsiella pneumoniae/effets des médicaments et des substances chimiques , Klebsiella pneumoniae/isolement et purification , Génome bactérien , Infections à Klebsiella/médecine vétérinaire , Infections à Klebsiella/microbiologie , Antibactériens/pharmacologie , Facteurs de virulence/génétique
4.
Nanomaterials (Basel) ; 14(15)2024 Jul 25.
Article de Anglais | MEDLINE | ID: mdl-39120356

RÉSUMÉ

We study theoretically the Josephson diode effect (JDE) when realized in a system composed of parallel-coupled double-quantum dots (DQDs) sandwiched between two semiconductor nanowires deposited on an s-wave superconductor surface. Due to the combined effects of proximity-induced superconductivity, strong Rashba spin-orbit interaction, and the Zeeman splitting inside the nanowires, a pair of Majorana bound states (MBSs) may possibly emerge at opposite ends of each nanowire. Different phase factors arising from the superconductor substrate can be generated in the coupling amplitudes between the DQDs and MBSs prepared at the left and right nanowires, and this will result in the Josephson current. We find that the critical Josephson currents in positive and negative directions are different from each other in amplitude within an oscillation period with respect to the magnetic flux penetrating through the system, a phenomenon known as the JDE. It arises from the quantum interference effect in this double-path device, and it can hardly occur in the system of one QD coupled to MBSs. Our results also show that the diode efficiency can reach up to 50%, but this depends on the overlap amplitude between the MBSs, as well as the energy levels of the DQDs adjustable by gate voltages. The present model is realizable within current nanofabrication technologies and may find practical use in the interdisciplinary field of Majorana and Josephson physics.

5.
Front Pharmacol ; 15: 1361733, 2024.
Article de Anglais | MEDLINE | ID: mdl-39130645

RÉSUMÉ

Introduction: Cytotoxic cerebral edema is a serious complication associated with cerebral ischemic stroke and is widely treated using the hypertonic dehydrant. Here, we propose, for the first time, the decrease of intracellular osmosis as a treatment strategy for alleviating cytotoxic cerebral edema. Methods: We established a fluorescence resonance energy transfer-based intermediate filament tension probe for the study and in situ evaluation of osmotic gradients, which were examined in real-time in living cells from primary cultures as well as cell lines. The MCAO rat model was used to confirm our therapy of cerebral edema. Results: Depolymerization of microfilaments/microtubules and the production of NLRP3 inflammasome resulted in an abundance of protein nanoparticles (PNs) in the glutamate-induced swelling of astrocytes. PNs induced changes in membrane potential and intracellular second messengers, thereby contributing to hyper-osmosis and the resultant astrocyte swelling via the activation of voltage-dependent nonselective ion channels. Therefore, multiple inhibitors of PNs, sodium and chloride ion channels were screened as compound combinations, based on a decrease in cell osmosis and astrocyte swelling, which was followed by further confirmation of the effectiveness of the compound combination against alleviated cerebral edema after ischemia. Discussion: The present study proposes new pathological mechanisms underlying "electrophysiology-biochemical signal-osmotic tension," which are responsible for cascade regulation in cerebral edema. It also explores various compound combinations as a potential treatment strategy for cerebral edema, which act by multi-targeting intracellular PNs and voltage-dependent nonselective ion flux to reduce astrocyte osmosis.

6.
Anal Chem ; 2024 Jul 11.
Article de Anglais | MEDLINE | ID: mdl-38989558

RÉSUMÉ

Heparan sulfate (HS) meshes within the glycocalyx on cell surfaces have protein recognition ability and have been crucial for gaining insights into vital bioprocesses, such as viral infection, cancer development, and inflammation. The protein recognition ability is determined by the mesh property and compositions of HS, although little attention has been paid to the effect of the mesh property on the recognition. An in-depth specificity study of protein-HS-mesh recognition is essential to illustrate related biological functions. Here, ordered porous layer interferometry is applied to study the interaction behavior between mimicked HS meshes and lactoferrin (LF). Our work aimed at mimicking HS meshes with heparin, a widely used substitute of HS, and analyzing the specific LF-heparin-mesh interaction mechanism by inhibiting the nonspecific interaction in a blended sample. We found that the counterion release-based electrostatic interaction is dominant in the specific LF-heparin-mesh recognition. Furthermore, we detail the contributions of nonspecific and specific interactions to the recognition. We illustrate that the concentrated charge distribution of the proteins appears to be primarily related to this robust, specific recognition.

7.
Appl Environ Microbiol ; : e0096824, 2024 Jul 31.
Article de Anglais | MEDLINE | ID: mdl-39082808

RÉSUMÉ

Hyperosmotic stress tolerance is crucial for Saccharomyces cerevisiae in producing value-added products from renewable feedstock. The limited understanding of its tolerance mechanism has impeded the application of these microbial cell factories. Previous studies have shown that Med3 plays a role in hyperosmotic stress in S. cerevisiae. However, the specific function of Med3 in hyperosmotic stress tolerance remains unclear. In this study, we showed that the deletion of the mediator Med3 impairs S. cerevisiae growth under hyperosmotic stress. Phenotypic analyses and yeast two-hybrid assays revealed that Med3 interacts with the transcription factor Stb5 to regulate the expression of the genes gnd1 and ald6, which are involved in NADPH production under hyperosmotic stress conditions. The deletion of med3 resulted in a decrease in intracellular NADPH content, leading to increased oxidative stress and elevated levels of intracellular reactive oxygen species under hyperosmotic stress, thereby impacting bud formation. These findings highlight the significant role of Med3 as a regulator in maintaining NADPH generation and redox homeostasis in S. cerevisiae during hyperosmotic stress.IMPORTANCEHyperosmotic stress tolerance in the host strain is a significant challenge for fermentation performance in industrial production. In this study, we showed that the S. cerevisiae mediator Med3 is essential for yeast growth under hyperosmotic conditions. Med3 interacts with the transcription factor Stb5 to regulate the expression of genes involved in the NADPH-generation system during hyperosmotic stress. Adequate NADPH ensures the timely removal of excess reactive oxygen species and supports bud formation under these conditions. This work highlights the crucial role of Med3 as a regulator in maintaining NADPH generation and redox homeostasis in S. cerevisiae during hyperosmotic stress.

8.
Water Res ; 263: 122161, 2024 Jul 26.
Article de Anglais | MEDLINE | ID: mdl-39084092

RÉSUMÉ

Recycling phosphorus from waste activated sludge (WAS) is an effective method to address the nonrenewable nature of phosphorus and mitigate environmental pollution. To overcome the challenge of low phosphorus recovery from WAS due to insufficient disintegration, a method using a citric acid-based natural deep eutectic solvent (CA-NADES) assisted with low-temperature pretreatment was proposed to efficiently release and recover phosphorus. The results of 31P nuclear magnetic resonance (NMR) confirmed that low-temperature pretreatment promoted the conversion of organic phosphorus (OP) to inorganic phosphorus (IP) and enhanced the effect of CA-NADES. Changes in the three-dimensional excitation-emission matrix (3D-EEM) and flow cytometry (FCM) indicated that the method of CA-NADES with low-temperature thermal simultaneously release IP and OP by disintegrating sludge flocs, dissolving extracellular polymeric substances (EPS) structure, and cracking cells. When 5 % (v/v) of CA-NADES was added and thermally treated at 60 °C for 30 min, 43 % of total phosphorus (TP) was released from the sludge. The concentrations of proteins and polysaccharides reached 826 and 331 mg/L, respectively, which were 6.30 and 14.43 times higher than those of raw sludge. The dewatering and settling of the sludge were also improved. Metals were either enriched in the solid phase or released into the liquid phase in small quantities (most efficiencies of less than 10 %) for subsequent clean recovery. The released phosphorus was successfully recovered as vivianite with a rate of 90 %. This study develops an efficient, green, and sustainable method for phosphorus recovery from sludge using NADES and provides new insights into the high-value conversion of sludge.

9.
Nat Commun ; 15(1): 5737, 2024 Jul 09.
Article de Anglais | MEDLINE | ID: mdl-38982157

RÉSUMÉ

Exploring the promiscuity of native enzymes presents a promising strategy for expanding their synthetic applications, particularly for catalyzing challenging reactions in non-native contexts. In this study, we explore the promiscuous potential of old yellow enzymes (OYEs) to facilitate the Morita-Baylis-Hillman reaction (MBH reaction), leveraging substrate similarities between MBH reaction and reduction reaction. Using mass spectrometry and spectroscopic techniques, we confirm promiscuity of GkOYE in both MBH and reduction reactions. By blocking H- and H+ transfer pathways, we engineer GkOYE.8, which loses its reduction ability but enhances its MBH activity. The structural basis of MBH reaction catalyzed by GkOYE.8 is obtained through mutation studies and kinetic simulations. Furthermore, enantiocomplementary mutants GkOYE.11 and GkOYE.13 are obtained by directed evolution, exhibiting the ability to accept various aromatic aldehydes and alkenes as substrates. This study demonstrates the potential of leveraging substrate similarities to unlock enzyme functionalities, enabling the catalysis of new-to-nature reactions.


Sujet(s)
Biocatalyse , Spécificité du substrat , Cinétique , Aldéhydes/métabolisme , Aldéhydes/composition chimique , Catalyse , Mutation , Alcènes/métabolisme , Alcènes/composition chimique , Protéines bactériennes/métabolisme , Protéines bactériennes/génétique , Protéines bactériennes/composition chimique , Ingénierie des protéines
10.
Nutrients ; 16(13)2024 Jun 25.
Article de Anglais | MEDLINE | ID: mdl-38999758

RÉSUMÉ

Globally, metabolic dysfunction-associated steatotic liver disease (MASLD), previously termed nonalcoholic fatty liver disease (NAFLD), is one of the most common liver disorders and is strongly associated with copper deficiency. To explore the potential effects and mechanisms of Lactiplantibacillus plantarum LPJZ-658, copper deficiency combined with a high-sugar diet-induced MASLD mouse model was utilized in this study. We fed 40-week-old (middle-aged) male C57BL/6 mice a copper-deficient and high-sugar diet for 16 weeks (CuDS), with supplementary LPJZ-658 for the last 6 weeks (CuDS + LPJZ-658). In this study, we measured body weight, liver weight, and serum biochemical markers. Lipid accumulation, histology, lipidomics, and sphingolipid metabolism-related enzyme expression were investigated to analyze liver function. Untargeted metabolomics was used to analyze the serum and the composition and abundance of intestinal flora. In addition, the correlation between differential liver lipid profiles, serum metabolites, and gut flora at the genus level was measured. The results show that LPJZ-658 significantly improves abnormal liver function and hepatic steatosis. The lipidomics analyses and metabolic pathway analysis identified sphingolipid, retinol, and glycerophospholipid metabolism as the most relevant metabolic pathways that characterized liver lipid dysregulation in the CuDS group. Consistently, RT-qPCR analyses revealed that the enzymes catalyzing sphingolipid metabolism that were significantly upregulated in the CuDS group were downregulated by the LPJZ-658 treatment. In addition, the serum metabolomics results indicated that the linoleic acid, taurine and hypotaurine, and ascorbate and aldarate metabolism pathways were associated with CuDS-induced MASLD. Notably, we found that treatment with LPJZ-658 partially reversed the changes in the differential serum metabolites. Finally, LPJZ-658 effectively regulated intestinal flora abnormalities and was significantly correlated with differential hepatic lipid species and serum metabolites. In conclusion, we elucidated the function and potential mechanisms of LPJZ-658 in alleviating copper deficiency combined with sugar-induced middle-aged MASLD and hope this will provide possible treatment strategies for improving MASLD.


Sujet(s)
Cuivre , Foie , Souris de lignée C57BL , Stéatose hépatique non alcoolique , Animaux , Mâle , Stéatose hépatique non alcoolique/étiologie , Stéatose hépatique non alcoolique/métabolisme , Souris , Cuivre/sang , Foie/métabolisme , Métabolisme lipidique , Microbiome gastro-intestinal/effets des médicaments et des substances chimiques , Modèles animaux de maladie humaine , Probiotiques/administration et posologie , Probiotiques/pharmacologie , Métabolomique , Lactobacillus plantarum , Lipidomique , Multi-omique
11.
Nanomaterials (Basel) ; 14(14)2024 Jul 16.
Article de Anglais | MEDLINE | ID: mdl-39057886

RÉSUMÉ

We study the electron tunneling (ET) and local Andreev reflection (AR) processes in a quantum dot (QD) coupled to the left and right ferromagnetic leads with noncollinear ferromagnetisms. In particular, we consider that the QD is also side-coupled to a nanowire hosting Majorana bound states (MBSs) at its ends. Our results show that when one mode of the MBSs is coupled simultaneously to both spin-up and spin-down electrons on the QD, the height of the central peak is different from that if the MBS is coupled to only one spin component electrons. The ET and AR conductances, which are mediated by the dot-MBS hybridization, strongly depend on the angle between the left and right magnetic moments in the leads. Interaction between the QD and the MBSs will result in sign change of the angle-dependent tunnel magnetoresistance. This is very different from the case when the QD is coupled to regular fermonic mode, and can be used for detecting the existence of MBSs, a current challenge in condensed matter physics under extensive investigations.

12.
Front Plant Sci ; 15: 1401050, 2024.
Article de Anglais | MEDLINE | ID: mdl-38974980

RÉSUMÉ

Introduction: Drought stress usually inhibits plant growth, which may increase the difficulty of greening slopes. Methods: In this study, we systematically investigated the effects of arbuscular mycorrhizal (AM) fungi on the growth and drought tolerance of two plant species, Festuca elata and Cassia glauca, in a vegetation concrete environment by exogenously inoculating AM fungi and setting three drought levels: well water, moderate drought and severe drought. The results showed that plant growth was significantly inhibited under drought stress; however, AM fungi inoculation significantly promoted plant height, root length, and above- and belowground biomass in these two plant species. Results: Compared with, those in the CK treatment, the greatest increases in the net photosynthesis rate, stomatal conductance and transpiration rate in the AM treatment group were 36.72%, 210.08%, and 66.41%, respectively. Moreover, inoculation with AM fungi increased plant superoxide dismutase and catalase activities by 4.70-150.73% and 9.10-95.70%, respectively, and reduced leaf malondialdehyde content by 2.79-55.01%, which alleviated the damage caused by oxidative stress. These effects alleviated the damage caused by oxidative stress and increased the content of soluble sugars and soluble proteins in plant leaves by 1.52-65.44% and 4.67-97.54%, respectively, which further increased the drought adaptability of plants. However, inoculation with AM fungi had different effects on different plants. Conclusion: In summary, this study demonstrated that the inoculation of AM fungi in vegetation concrete environments can significantly increase plant growth and drought tolerance. The plants that formed a symbiotic structure with AM fungi had a larger root uptake area, greater water uptake capacity, and greater photosynthesis and gas exchange efficiency. In addition, AM fungi inoculation further increased the drought adaptability of the plants by increasing their antioxidant enzyme activity and regulating their metabolite content. These findings are highly important for promoting plant growth and increasing drought tolerance under drought conditions, especially for potential practical applications in areas such as slope protection, and provide useful references for future ecological engineering and sustainable development.

13.
BMC Psychiatry ; 24(1): 479, 2024 Jul 01.
Article de Anglais | MEDLINE | ID: mdl-38951775

RÉSUMÉ

BACKGROUND: Increasing evidence suggests that leptin is involved in the pathology of autism spectrum disorder (ASD). In this study, our objective was to investigate the levels of leptin in the blood of children with ASD and to examine the overall profile of adipokine markers in ASD through meta-analysis. METHODS: Leptin concentrations were measured using an enzyme-linked immunosorbent assay (ELISA) kit, while adipokine profiling, including leptin, was performed via meta-analysis. Original reports that included measurements of peripheral adipokines in ASD patients and healthy controls (HCs) were collected from databases such as Web of Science, PubMed, and Cochrane Library. These studies were collected from September 2022 to September 2023 and followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Standardized mean differences were calculated using a random effects model for the meta-analysis. Additionally, we performed meta-regression and explored heterogeneity among studies. RESULTS: Our findings revealed a significant increase in leptin levels in children with ASD compared to HCs (p = 0.0319). This result was consistent with the findings obtained from the meta-analysis (p < 0.001). Furthermore, progranulin concentrations were significantly reduced in children with ASD. However, for the other five adipokines analyzed, there were no significant differences observed between the children with ASD and HCs children. Heterogeneity was found among the studies, and the meta-regression analysis indicated that publication year and latitude might influence the results of the meta-analysis. CONCLUSIONS: These findings provide compelling evidence that leptin levels are increased in children with ASD compared to healthy controls, suggesting a potential mechanism involving adipokines, particularly leptin, in the pathogenesis of ASD. These results contribute to a better understanding of the pathology of ASD and provide new insights for future investigations.


Sujet(s)
Adipokines , Trouble du spectre autistique , Leptine , Humains , Trouble du spectre autistique/sang , Leptine/sang , Enfant , Adipokines/sang , Marqueurs biologiques/sang
14.
ACS Nano ; 18(24): 15991-16001, 2024 Jun 18.
Article de Anglais | MEDLINE | ID: mdl-38829730

RÉSUMÉ

Phase heterogeneity of bromine-iodine (Br-I) mixed wide-bandgap (WBG) perovskites has detrimental effects on solar cell performance and stability. Here, we report a heterointerface anchoring strategy to homogenize the Br-I distribution and mitigate the segregation of Br-rich WBG-perovskite phases. We find that methoxy-substituted phenyl ethylammonium (x-MeOPEA+) ligands not only contribute to the crystal growth with vertical orientation but also promote halide homogenization and defect passivation near the buried perovskite/hole transport layer (HTL) interface as well as reduce trap-mediated recombination. Based on improvements in WBG-perovskite homogeneity and heterointerface contacts, NiOx-based opaque WBG-perovskite solar cells (WBG-PSCs) achieved impressive open-circuit voltage (Voc) and fill factor (FF) values of 1.22 V and 83%, respectively. Moreover, semitransparent WBG-PSCs exhibit a PCE of 18.5% (15.4% for the IZO front side) and a high FF of 80.7% (79.4% for the IZO front side) for a designated illumination area (da) of 0.12 cm2. Such a strategy further enables 24.3%-efficient two-terminal perovskite/silicon (double-polished) tandem solar cells (da of 1.159 cm2) with a high Voc of over 1.90 V. The tandem devices also show high operational stability over 1000 h during T90 lifetime measurements.

15.
Food Chem ; 457: 140165, 2024 Nov 01.
Article de Anglais | MEDLINE | ID: mdl-38936118

RÉSUMÉ

Para-hydroxybenzoic acid (PHBA) is extensively used as an additive in the food and cosmetics industries, significantly enhancing product shelf life and stability. While microbial fermentation offers an environment-friendly and sustainable method for producing PHBA, the titer and productivity are limited due to product toxicity and complex metabolic flux distributions. Here, we initially redesigned a L-phenylalanine-producing Escherichia coli by employing rational metabolic engineering strategies, resulting in the production of PHBA reached the highest reported level of 14.17 g/L. Subsequently, a novel accelerated evolution system was devised comprising deaminase, the alpha subunit of RNA polymerase, an uracil-DNA glycosylase inhibitor, and the PHBA-responsive promoter PyhcN. This system enabled us to obtain a mutant strain exhibiting a 47% increase in the half-inhibitory concentration (IC50) for PHBA within 15 days. Finally, the evolved strain achieved a production of 21.35 g/L PHBA in a 5-L fermenter, with a yield of 0.19 g/g glucose and a productivity rate of 0.44 g/L/h. This engineered strain emerges as a promising candidate for industrial production of PHBA through an eco-friendly approach.


Sujet(s)
Escherichia coli , Fermentation , Génie métabolique , Parabènes , Escherichia coli/génétique , Escherichia coli/métabolisme , Parabènes/métabolisme
16.
Sheng Wu Gong Cheng Xue Bao ; 40(6): 1882-1894, 2024 Jun 25.
Article de Chinois | MEDLINE | ID: mdl-38914498

RÉSUMÉ

1,4-cyclohexanedimethylamine (1,4-BAC) is an important monomer for bio-based materials, it finds wide applications in various fields including organic synthesis, medicine, chemical industry, and materials. At present, its synthesis primarily relies on chemical method, which suffer from issues such as expensive metal catalyst, harsh reaction conditions, and safety risks. Therefore, it is necessary to explore greener alternatives for its synthesis. In this study, a two-bacterium three-enzyme cascade conversion pathway was successfully developed to convert 1,4-cyclohexanedicarboxaldehyde to 1,4-cyclohexanedimethylamine. This pathway used Escherichia coli derived aminotransferase (EcTA), Saccharomyces cerevisiae derived glutamate dehydrogenase (ScGlu-DH), and Candida boidinii derived formate dehydrogenase (CbFDH). Through structure-guided protein engineering, a beneficial mutant, EcTAF91Y, was obtained, exhibiting a 2.2-fold increase in specific activity and a 1.9-fold increase in kcat/Km compared to that of the wild type. By constructing recombinant strains and optimizing reaction conditions, it was found that under the optimal conditions, a substrate concentration of 40 g/L could produce (27.4±0.9) g/L of the product, corresponding to a molar conversion rate of 67.5%±2.1%.


Sujet(s)
Escherichia coli , Saccharomyces cerevisiae , Escherichia coli/métabolisme , Escherichia coli/génétique , Saccharomyces cerevisiae/métabolisme , Saccharomyces cerevisiae/génétique , Saccharomyces cerevisiae/enzymologie , Transaminases/métabolisme , Transaminases/génétique , Ingénierie des protéines , Glutamate dehydrogenase/métabolisme , Glutamate dehydrogenase/génétique , Formate dehydrogenases/métabolisme , Formate dehydrogenases/génétique , Candida/enzymologie , Candida/métabolisme , Cyclohexylamines/métabolisme
17.
BMC Psychiatry ; 24(1): 439, 2024 Jun 12.
Article de Anglais | MEDLINE | ID: mdl-38867159

RÉSUMÉ

BACKGROUND: To analyze the economic benefits of paliperidone palmitate in the treatment of schizophrenia. METHODS: We collected 546 patients who met the diagnostic criteria for schizophrenia according to the 《International Statistical Classification of Diseases and Related Health Problems,10th》(ICD-10). We gathered general population data such as gender, age, marital status, and education level, then initiated treatment with paliperidone palmitate. Then Follow-up evaluations were conducted at 1, 3, 6, 9, and 12 months after the start of treatment to assess clinical efficacy, adverse reactions, and injection doses. We also collected information on the economic burden before and after 12 months of treatment, as well as the number of outpatient visits and hospitalizations in the past year to analyze economic benefits. RESULTS: The baseline patients totaled 546, with 239 still receiving treatment with paliperidone palmitate 12 months later. After 12 months of treatment, the number of outpatient visits per year increased compared to before (4 (2,10) vs. 12 (4,12), Z=-5.949, P < 0.001), while the number of hospitalizations decreased (1 (1,3) vs. 1 (1,2), Z = 5.625, P < 0.001). The inpatient costs in the direct medical expenses of patients after 12 months of treatment decreased compared to before (5000(2000,12000) vs. 3000 (1000,8050), P < 0.05), while there was no significant change in outpatient expenses and direct non-medical expenses (transportation, accommodation, meal, and family accompanying expenses, etc.) (P > 0.05); the indirect costs of patients after 12 months of treatment (lost productivity costs for patients and families, economic costs due to destructive behavior, costs of seeking non-medical assistance) decreased compared to before (300(150,600) vs. 150(100,200), P < 0.05). CONCLUSION: Palmatine palmitate reduces the number of hospitalizations for patients, as well as their direct and indirect economic burdens, and has good economic benefits.


Sujet(s)
Neuroleptiques , Palmitate de palipéridone , Schizophrénie , Humains , Palmitate de palipéridone/usage thérapeutique , Palmitate de palipéridone/économie , Palmitate de palipéridone/administration et posologie , Schizophrénie/traitement médicamenteux , Schizophrénie/économie , Mâle , Femelle , Neuroleptiques/économie , Neuroleptiques/usage thérapeutique , Adulte , Adulte d'âge moyen , Hospitalisation/économie , Hospitalisation/statistiques et données numériques , Études de cohortes , Coûts indirects de la maladie , Résultat thérapeutique
18.
ACS Synth Biol ; 13(6): 1879-1892, 2024 Jun 21.
Article de Anglais | MEDLINE | ID: mdl-38847341

RÉSUMÉ

Aromatic d-amino acids (d-AAs) play a pivotal role as important chiral building blocks and key intermediates in fine chemical and drug synthesis. Meso-diaminopimelate dehydrogenase (DAPDH) serves as an excellent biocatalyst in the synthesis of d-AAs and their derivatives. However, its strict substrate specificity and the lack of efficient engineering methods have hindered its widespread application. Therefore, this study aims to elucidate the catalytic mechanism underlying DAPDH from Proteus vulgaris (PvDAPDH) through the examination of its crystallographic structure, computational simulations of potential energies and molecular dynamics simulations, and site-directed mutagenesis. Mechanism-guided computational design showed that the optimal mutant PvDAPDH-M3 increased specific activity and catalytic efficiency (kcat/Km) for aromatic keto acids up to 124-fold and 92.4-fold, respectively, compared to that of the wild type. Additionally, it expanded the substrate scope to 10 aromatic keto acid substrates. Finally, six high-value-added aromatic d-AAs and their derivatives were synthesized using a one-pot three-enzyme cascade reaction, exhibiting a good conversion rate ranging from 32 to 84% and excellent stereoselectivity (enantiomeric excess >99%). These findings provide a potential synthetic pathway for the green industrial production of aromatic d-AAs.


Sujet(s)
Amino-acid oxidoreductases , Acides aminés aromatiques , Simulation de dynamique moléculaire , Mutagenèse dirigée , Amino-acid oxidoreductases/métabolisme , Amino-acid oxidoreductases/génétique , Amino-acid oxidoreductases/composition chimique , Spécificité du substrat , Acides aminés aromatiques/métabolisme , Acides aminés aromatiques/biosynthèse , Proteus vulgaris/enzymologie , Proteus vulgaris/génétique , Biocatalyse , Protéines bactériennes/génétique , Protéines bactériennes/métabolisme , Protéines bactériennes/composition chimique
19.
BMC Vet Res ; 20(1): 274, 2024 Jun 26.
Article de Anglais | MEDLINE | ID: mdl-38918815

RÉSUMÉ

BACKGROUND: Acinetobacter lwoffii (A. lwoffii) is a Gram-negative bacteria common in the environment, and it is the normal flora in human respiratory and digestive tracts. The bacteria is a zoonotic and opportunistic pathogen that causes various infections, including nosocomial infections. The aim of this study was to identify A. lwoffii strains isolated from bovine milk with subclinical mastitis in China and get a better understanding of its antimicrobial susceptibility and resistance profile. This is the first study to analyze the drug resistance spectrum and corresponding mechanisms of A. lwoffii isolated in raw milk. RESULTS: Four A. lwoffii strains were isolated by PCR method. Genetic evolution analysis using the neighbor-joining method showed that the four strains had a high homology with Acinetobacter lwoffii. The strains were resistant to several antibiotics and carried 17 drug-resistance genes across them. Specifically, among 23 antibiotics, the strains were completely susceptible to 6 antibiotics, including doxycycline, erythromycin, polymyxin, clindamycin, imipenem, and meropenem. In addition, the strains showed variable resistance patterns. A total of 17 resistance genes, including plasmid-mediated resistance genes, were detected across the four strains. These genes mediated resistance to 5 classes of antimicrobials, including beta-lactam, aminoglycosides, fluoroquinolones, tetracycline, sulfonamides, and chloramphenicol. CONCLUSION: These findings indicated that multi-drug resistant Acinetobacter lwoffii strains exist in raw milk of bovine with subclinical mastitis. Acinetobacter lwoffii are widespread in natural environmental samples, including water, soil, bathtub, soap box, skin, pharynx, conjunctiva, saliva, gastrointestinal tract, and vaginal secretions. The strains carry resistance genes in mobile genetic elements to enhance the spread of these genes. Therefore, more attention should be paid to epidemiological surveillance and drug resistant A. lwoffii.


Sujet(s)
Acinetobacter , Antibactériens , Mammite bovine , Lait , Animaux , Bovins , Mammite bovine/microbiologie , Mammite bovine/épidémiologie , Femelle , Acinetobacter/isolement et purification , Acinetobacter/génétique , Acinetobacter/effets des médicaments et des substances chimiques , Lait/microbiologie , Chine/épidémiologie , Antibactériens/pharmacologie , Tests de sensibilité microbienne/médecine vétérinaire , Infections à Acinetobacter/médecine vétérinaire , Infections à Acinetobacter/microbiologie , Infections à Acinetobacter/épidémiologie , Résistance bactérienne aux médicaments/génétique , Multirésistance bactérienne aux médicaments/génétique
20.
Angew Chem Int Ed Engl ; 63(32): e202406060, 2024 08 05.
Article de Anglais | MEDLINE | ID: mdl-38789390

RÉSUMÉ

The hydroxylation of remote C(sp3)-H bonds in aliphatic amino acids yields crucial precursors for the synthesis of high-value compounds. However, accurate regulation of the regioselectivity of remote C(sp3)-H bonds hydroxylation in aliphatic amino acids continues to be a common challenge in chemosynthesis and biosynthesis. In this study, the Fe(II)/α-ketoglutarate-dependent dioxygenase from Bacillus subtilis (BlAH) was mined and found to catalyze hydroxylation at the γ and δ sites of aliphatic amino acids. Crystal structure analysis, molecular dynamics simulations, and quantum chemical calculations revealed that regioselectivity was regulated by the spatial effect of BlAH. Based on these results, the spatial effect of BlAH was reconstructed to stabilize the transition state at the δ site of aliphatic amino acids, thereby successfully reversing the γ site regioselectivity to the δ site. For example, the regioselectivity of L-Homoleucine (5 a) was reversed from the γ site (1 : 12) to the δ site (>99 : 1). The present study not only expands the toolbox of biocatalysts for the regioselective functionalization of remote C(sp3)-H bonds, but also provides a theoretical guidance for the precision-driven modification of similarly remote C(sp3)-H bonds in complex molecules.


Sujet(s)
Acides aminés , Bacillus subtilis , Dioxygenases , Acides cétoglutariques , Hydroxylation , Bacillus subtilis/enzymologie , Dioxygenases/métabolisme , Dioxygenases/composition chimique , Acides cétoglutariques/métabolisme , Acides cétoglutariques/composition chimique , Acides aminés/composition chimique , Acides aminés/métabolisme , Stéréoisomérie , Composés du fer II/composition chimique , Composés du fer II/métabolisme , Simulation de dynamique moléculaire
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