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1.
J Hazard Mater ; 472: 134551, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38743979

RESUMO

Most hyperaccumulators cannot maintain vigorous growth throughout the year, which may result in a low phytoextraction efficiency for a few months. In the present study, rotation of two hyperaccumulators is proposed to address this issue. An 18-month field experiment was conducted to evaluate the phytoextraction efficiency of Cd by the monoculture and rotation of Celosia argentea and Sedum plumbizincicola. The results showed that rotation increased amount of extracted Cd increased by 2.3 and 1.6 times compared with monoculture of C. argentea and S. plumbizincicola. In rotation system, the biomass of S. plumbizincicola and Cd accumulation in C. argentea increased by 54.4% and 40.7%, respectively. Rotation reduced fallow time and increased harvesting frequency, thereby enhancing Cd phytoextraction. Planting C. argentea significantly decreased soil pathogenic microbes and increased the abundances of plant growth-promoting rhizobacteria (PGPR) and 1-aminocyclopropane-1-carboxylate (ACC) deaminase genes, which may be beneficial for the growth of S. plumbizincicola. Planting S. plumbizincicola increased the abundance of sulfur oxidization (SOX) system genes and decreased soil pH (p < 0.05), thereby increasing the Cd uptake by C. argentea. These findings indicated that rotation of C. argentea and S. plumbizincicola is a promising method for promoting Cd phytoextraction.

2.
J Am Chem Soc ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38747066

RESUMO

Ni-rich cathodes are some of the most promising candidates for advanced lithium-ion batteries, but their available capacities have been stagnant due to the intrinsic Li+ storage sites. Extending the voltage window down can induce the phase transition from O3 to 1T of LiNiO2-derived cathodes to accommodate excess Li+ and dramatically increase the capacity. By setting the discharge cutoff voltage of LiNi0.6Co0.2Mn0.2O2 to 1.4 V, we can reach an extremely high capacity of 393 mAh g-1 and an energy density of 1070 Wh kg-1 here. However, the phase transition causes fast capacity decay and related structural evolution is rarely understood, hindering the utilization of this feature. We find that the overlithiated phase transition is self-limiting, which will transform into solid-solution reaction with cycling and make the cathode degradation slow down. This is attributed to the migration of abundant transition metal ions into lithium layers induced by the overlithiation, allowing the intercalation of overstoichiometric Li+ into the crystal without the O3 framework change. Based on this, the wide-potential cycling stability is further improved via a facile charge-discharge protocol. This work provides deep insight into the overstoichiometric Li+ storage behaviors in conventional layered cathodes and opens a new avenue toward high-energy batteries.

3.
Materials (Basel) ; 17(9)2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38730890

RESUMO

A modified 3D re-entrant honeycomb is designed and fabricated utilizing Laser Cladding Deposition (LCD) technology, the mechanical properties of which are systematically investigated by experimental and finite element (FE) methods. Firstly, the influences of honeycomb angle on localized deformation and the response of force are studied by an experiment. Experimental results reveal that the honeycomb angles have a significant effect on deformation and force. Secondly, a series of numerical studies are conducted to analyze stress characteristics and energy absorption under different angles (α) and velocities (v). It is evident that two variables play an important role in stress and energy. Thirdly, response surface methodology (RSM) and the Non-Dominated Sorting Genetic Algorithm II (NSGA-II) are implemented with high precision to solve multi-objective optimization. Finally, the final compromise solution is determined based on the fitness function, with an angle of 49.23° and an impact velocity of 16.40 m/s. Through simulation verification, the errors of energy absorption (EA) and peak crush stress (PCS) are 9.26% and 0.4%, respectively. The findings of this study offer valuable design guidance for selecting the optimal design parameters under the same mass conditions to effectively enhance the performance of the honeycomb.

4.
Biotechnol Lett ; 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38733437

RESUMO

Chiral epichlorohydrin (ECH) is an attractive intermediate for chiral pharmaceuticals and chemicals preparation. The asymmetric synthesis of chiral ECH using 1,3-dicholoro-2-propanol (1,3-DCP) catalyzed by a haloalcohol dehalogenase (HHDH) was considered as a feasible approach. However, the reverse ring opening reaction caused low optical purity of chiral ECH, thus severely restricts the industrial application of HHDHs. In the present study, a novel selective conformation adjustment strategy was developed with an engineered HheCPS to regulate the kinetic parameters of the forward and reverse reactions, based on site saturation mutation and molecular simulation analysis. The HheCPS mutant E85P was constructed with a markable change in the conformation of (S)-ECH in the substrate pocket and a slight impact on the interaction between 1,3-DCP and the enzyme, which resulted in the kinetic deceleration of the reverse reactions. Compared with HheCPS, the catalytic efficiency (kcat(S)-ECH/Km(S)-ECH) of the reversed reaction dropped to 0.23-fold (from 0.13 to 0.03 mM-1 s-1), while the catalytic efficiency (kcat(1,3-DCP)/Km(1,3-DCP)) of the forward reaction only reduced from 0.83 to 0.71 mM-1 s-1. With 40 mM 1,3-DCP as substrate, HheCPS E85P catalyzed the synthesis of (S)-ECH with the yield up to 55.35% and the e.e. increased from 92.54 to >99%. Our work provided an effective approach for understanding the stereoselective catalytic mechanism as well as the green manufacturing of chiral epoxides.

5.
J Hazard Mater ; 473: 134590, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38762990

RESUMO

Phytoremediation, an eco-friendly approach for mitigating heavy metal contamination, is reliant on hyperaccumulators. This study focused on Leersia hexandra Swart, a known chromium (Cr) hyperaccumulator with demonstrated tolerance to multiple heavy metals. Our objective was to investigate its response to simultaneous Cr and nickel (Ni) stress over 12 days. Results from physiological experiments demonstrated a significant increase in the activities of antioxidant enzymes (APX, SOD, CAT) and glutathione (GSH) content under Cr and Ni stress, indicating enhanced antioxidant mechanisms. Transcriptome analysis revealed that stress resulted in the differential expression of 27 genes associated with antioxidant activity and metal binding, including APX, SOD, CAT, GSH, metallothionein (MT), and nicotinamide (NA). Among them, twenty differentially expressed genes (DEGs) related to GSH metabolic cycle were identified. Notably, GSTU6, GND1, and PGD were the top three related genes, showing upregulation with fold changes of 4.57, 6.07, and 3.76, respectively, indicating their crucial role in metal tolerance. The expression of selected DEGs was validated by quantitative real-time PCR, confirming the reliability of RNA-Seq data. Metabolomic analysis revealed changes in 1121 metabolites, with amino acids, flavonoids, and carbohydrates being the most affected. Furthermore, glucosinolate biosynthesis and amino acid biosynthesis pathways were represented in the KEGG pathway of differentially expressed metabolites (DEMs). This study provides insights into the tolerance mechanisms of L. hexandra under the co-stress of Cr and Ni, offering a new perspective for enhancing its remediation performance.

6.
Yi Chuan ; 46(5): 360-372, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38763771

RESUMO

In order to understand the progress and frontier in the application of BSA(bulked segregant analysis) method in crop breeding and to reflect objectively the contribution of different countries, institutions and researchers in this field at home and abroad, this study analyzed 2111 items in the WOS (Web of Science) database from 2000 to 2023 and 446 items in the CNKI (China National through Knowledge Infrastructure) database from 2003 to 2023, regarding the researches of the application of BSA in crop breeding, basing on bibliometric analysis methods using CiteSpace software including keyword co-occurrence analysis, highlight word analysis, keyword clustering analysis, clustering timeline analysis and author co-citation. The results showed that there was an consistent increasing trend in the publication number of the application of BSA in crop breeding both in the domestic and foreign journals year by year. Ranking of the top countries according to the number of publications was China, the United States and India. The Huazhong Agricultural University displayed the highest number of publications in the CNKI database, while the Chinese Academy of Agricultural Sciences was found to have the highest number of publications in the WOS database. The published articles related to the application of BSA in crop breeding abroad mainly focused on the disciplines such as plant science, agronomy, horticulture and genetics, while those in China mainly concentrated on such disciplines as plant science, plant protection, horticulture and biology. The top three authors in terms of influence in the field of appling BSA in crop breeding were Michelmore RW, Kosambi DD and Li H, while Michelmore RW, Lander ES and Li H had closer cooperations with other authors. The top three crops relating to the studies of BSA were rice(Oryza sativa), soybean(Glycine max), corn(Zea mays L.) with the hot spot traits of disease resistance and plant height domestically. The top three crops involving the studies of BSA were rice, Arabidopsis thaliana and wheat(Triticum aestivum L.) with hot spot traits of disease resistance abroad. Up to now, BSA was mainly used to localize and functionally verify the candidate genes linking target traits and the mutated genes in crops in the domestical documents, while the foreign published studies based on BSA were mainly focused on the fine mapping and functional verification of target trait genes aiming at the revelation of genetic mechanisms in crops. Research frontier analysis indicated that rice, peanuts(Arachis hypogaea L.), upland cotton(Gossypium hirsutum L.) would be the main objects of studies concerning application of BSA in crop breeding with the hot topics of crop mutants and crop metabolites in the future.


Assuntos
Bibliometria , Produtos Agrícolas , Melhoramento Vegetal , Produtos Agrícolas/genética , Melhoramento Vegetal/métodos , China
7.
Funct Integr Genomics ; 24(3): 81, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709433

RESUMO

One of the primary concerns for the survival of the human species is the growing demand for food brought on by an increasing global population. New developments in genome-editing technology present promising opportunities for the growth of wholesome and prolific farm animals. Genome editing in large animals is used for a variety of purposes, including biotechnology to improve food production, animal health, and pest management, as well as the development of animal models for fundamental research and biomedicine. Genome editing entails modifying genetic material by removing, adding, or manipulating particular DNA sequences from a particular locus in a way that does not happen naturally. The three primary genome editors are CRISPR/Cas 9, TALENs, and ZFNs. Each of these enzymes is capable of precisely severing nuclear DNA at a predetermined location. One of the most effective inventions is base editing, which enables single base conversions without the requirement for a DNA double-strand break (DSB). As reliable methods for precise genome editing in studies involving animals, cytosine and adenine base editing are now well-established. Effective zygote editing with both cytosine and adenine base editors (ABE) has resulted in the production of animal models. Both base editors produced comparable outcomes for the precise editing of point mutations in somatic cells, advancing the field of gene therapy. This review focused on the principles, methods, recent developments, outstanding applications, the advantages and disadvantages of ZFNs, TALENs, and CRISPR/Cas9 base editors, and prime editing in diverse lab and farm animals. Additionally, we address the methodologies that can be used for gene regulation, base editing, and epigenetic alterations, as well as the significance of genome editing in animal models to better reflect real disease. We also look at methods designed to increase the effectiveness and precision of gene editing tools. Genome editing in large animals is used for a variety of purposes, including biotechnology to improve food production, animal health, and pest management, as well as the development of animal models for fundamental research and biomedicine. This review is an overview of the existing knowledge of the principles, methods, recent developments, outstanding applications, the advantages and disadvantages of zinc finger nucleases (ZFNs), transcription-activator-like endonucleases (TALENs), and clustered regularly interspaced short palindromic repeats associated protein 9 (CRISPR/Cas 9), base editors and prime editing in diverse lab and farm animals, which will offer better and healthier products for the entire human race.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Gado , Edição de Genes/métodos , Animais , Gado/genética , Resistência à Doença/genética
8.
Appl Microbiol Biotechnol ; 108(1): 320, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709366

RESUMO

The unspecific peroxygenase (UPO) from Cyclocybe aegerita (AaeUPO) can selectively oxidize C-H bonds using hydrogen peroxide as an oxygen donor without cofactors, which has drawn significant industrial attention. Many studies have made efforts to enhance the overall activity of AaeUPO expressed in Komagataella phaffii by employing strategies such as enzyme-directed evolution, utilizing appropriate promoters, and screening secretion peptides. Building upon these previous studies, the objective of this study was to further enhance the expression of a mutant of AaeUPO with improved activity (PaDa-I) by increasing the gene copy number, co-expressing chaperones, and optimizing culture conditions. Our results demonstrated that a strain carrying approximately three copies of expression cassettes and co-expressing the protein disulfide isomerase showed an approximately 10.7-fold increase in volumetric enzyme activity, using the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) as the substrate. After optimizing the culture conditions, the volumetric enzyme activity of this strain further increased by approximately 48.7%, reaching 117.3 U/mL. Additionally, the purified catalytic domain of PaDa-I displayed regioselective hydroxylation of R-2-phenoxypropionic acid. The results of this study may facilitate the industrial application of UPOs. KEY POINTS: • The secretion of the catalytic domain of PaDa-I can be significantly enhanced through increasing gene copy numbers and co-expressing of protein disulfide isomerase. • After optimizing the culture conditions, the volumetric enzyme activity can reach 117.3 U/mL, using the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) as the substrate. • The R-2-phenoxypropionic acid can undergo the specific hydroxylation reaction catalyzed by catalytic domain of PaDa-I, resulting in the formation of R-2-(4-hydroxyphenoxy)propionic acid.


Assuntos
Oxigenases de Função Mista , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Oxigenases de Função Mista/química , Saccharomycetales/genética , Saccharomycetales/enzimologia , Saccharomycetales/metabolismo , Dosagem de Genes , Isomerases de Dissulfetos de Proteínas/genética , Isomerases de Dissulfetos de Proteínas/metabolismo , Expressão Gênica , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/química
9.
Drug Des Devel Ther ; 18: 1439-1457, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38707616

RESUMO

Background: Acteoside, an active ingredient found in various medicinal herbs, is effective in the treatment of diabetic kidney disease (DKD); however, the intrinsic pharmacological mechanism of action of acteoside in the treatment of DKD remains unclear. This study utilizes a combined approach of network pharmacology and experimental validation to investigate the potential molecular mechanism systematically. Methods: First, acteoside potential targets and DKD-associated targets were aggregated from public databases. Subsequently, utilizing protein-protein interaction (PPI) networks, alongside GO and KEGG pathway enrichment analyses, we established target-pathway networks to identify core potential therapeutic targets and pathways. Further, molecular docking facilitated the confirmation of interactions between acteoside and central targets. Finally, the conjectured molecular mechanisms of acteoside against DKD were verified through experimentation on unilateral nephrectomy combined with streptozotocin (STZ) rat model. The underlying downstream mechanisms were further investigated. Results: Network pharmacology identified 129 potential intersected targets of acteoside for DKD treatment, including targets such as AKT1, TNF, Casp3, MMP9, SRC, IGF1, EGFR, HRAS, CASP8, and MAPK8. Enrichment analyses indicated the PI3K-Akt, MAPK, Metabolic, and Relaxin signaling pathways could be involved in this therapeutic context. Molecular docking revealed high-affinity binding of acteoside to PIK3R1, AKT1, and NF-κB1. In vivo studies validated the therapeutic efficacy of acteoside, demonstrating reduced blood glucose levels, improved serum Scr and BUN levels, decreased 24-hour urinary total protein (P<0.05), alongside mitigated podocyte injury (P<0.05) and ameliorated renal pathological lesions. Furthermore, this finding indicates that acteoside inhibits the expression of pyroptosis markers NLRP3, Caspase-1, IL-1ß, and IL-18 through the modulation of the PI3K/AKT/NF-κB pathway. Conclusion: Acteoside demonstrates renoprotective effects in DKD by regulating the PI3K/AKT/NF-κB signaling pathway and alleviating pyroptosis. This study explores the pharmacological mechanism underlying acteoside's efficacy in DKD treatment, providing a foundation for further basic and clinical research.


Assuntos
Diabetes Mellitus Experimental , Nefropatias Diabéticas , Glucosídeos , Simulação de Acoplamento Molecular , Farmacologia em Rede , Fenóis , Polifenóis , Estreptozocina , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/metabolismo , Animais , Ratos , Glucosídeos/farmacologia , Glucosídeos/química , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Masculino , Fenóis/farmacologia , Fenóis/química , Ratos Sprague-Dawley
10.
Mol Genet Genomic Med ; 12(4): e2425, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38562051

RESUMO

BACKGROUND: To explore the clinical application value of pre-conception expanded carrier screening (PECS) in the Chinese Han ethnicity population of childbearing age. METHODS: The results of genetic testing of infertile parents who underwent PECS in the Reproductive Medicine Center of the Second Affiliated Hospital of Zhengzhou University, China, from September 2019 to December 2021, were retrospectively analyzed. The carrier rate of single gene disease, the detection rate of high-risk parents, and the clinical outcome of high-risk parents were statistically analyzed. RESULTS: A total of 1372 Chinese Han ethnicity patients underwent PECS, among which 458 patients underwent the extended 108-gene test, their overall carrier rate was 31.7%, and the detection rate of high-risk parents was 0.3%. The highest carrier rates were SLC22A (2.4%), ATP7B (2.4%), MMACHC (2.2%), PAH (1.8%), GALC (1.8%), MLC1 (1.3%), UNC13D (1.1%), CAPN3 (1.1%), and PKHD1 (1.1%). There were 488 women with fragile X syndrome-FMR1 gene detection, and 6 patients (1.2%) had FMR1 gene mutation. A total of 426 patients were screened for spinal muscular atrophy-SMN1, and the carrier rate was 3.5%, and the detection rate of parents' co-carrier was 0.5%. CONCLUSION: Monogenic recessive hereditary diseases had a high carrier rate in the population. Pre-pregnancy screening could provide good prenatal and postnatal care guidance for patients and preimplantation genetic testing for monogenic/single gene disorders (PGT-M) and prenatal diagnosis could provide more precise reproductive choices for high-risk parents.


Assuntos
Testes Genéticos , Atrofia Muscular Espinal , Gravidez , Humanos , Feminino , Estudos Retrospectivos , Testes Genéticos/métodos , Diagnóstico Pré-Natal/métodos , Mutação , Atrofia Muscular Espinal/genética , Proteína do X Frágil da Deficiência Intelectual/genética , Oxirredutases/genética , Proteínas de Membrana/genética
11.
Artigo em Inglês | MEDLINE | ID: mdl-38639560

RESUMO

Rechargeable lithium-sulfur (Li-S) batteries are promising for high-energy storage. However, conventional redox reactions involving sulfur (S) and lithium (Li) can lead to unstable intermediates. Over the past decade, many strategies have emerged to address this challenge, enabling nonconventional electrochemical reactions in Li-S batteries. In our Perspective, we provide a brief review of these strategies and highlight their potential benefits. Specifically, our group has pioneered a top-down approach, investigating Li-S reactions at molecular and subatomic levels, as demonstrated in our recent work on stable S isotopes. These insights not only enhance understanding of charge transfer and storage properties but also offer exciting opportunities for advancements in battery materials research.

12.
ACS Appl Mater Interfaces ; 16(15): 18971-18979, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38578663

RESUMO

The formation of a solid electrolyte interphase on carbon anodes causes irreversible loss of Na+ ions, significantly compromising the energy density of Na-ion full cells. Sodium compensation additives can effectively address the irreversible sodium loss but suffer from high decomposition voltage induced by low electrochemical activity. Herein, we propose a universal electrocatalytic sodium compensation strategy by introducing a carbon nanotube (CNT)/MnO2 catalyst to realize full utilization of sodium compensation additives at a much-reduced decomposition voltage. The well-organized CNT/MnO2 composite with high catalytic activity, good electronic conductivity, and abundant reaction sites enables sodium compensation additives to decompose at significantly reduced voltages (from 4.40 to 3.90 V vs Na+/Na for sodium oxalate, 3.88 V for sodium carbonate, and even 3.80 V for sodium citrate). As a result, sodium oxalate as the optimal additive achieves a specific capacity of 394 mAh g-1, almost reaching its theoretical capacity in the first charge, increasing the energy density of the Na-ion full cell from 111 to 158 Wh kg-1 with improved cycle stability and rate capability. This work offers a valuable approach to enhance sodium compensation efficiency, promising high-performance energy storage devices in the future.

13.
Bioprocess Biosyst Eng ; 47(6): 841-850, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38676737

RESUMO

D-Allulose 3-epimerase (DAE) is a vital biocatalyst for the industrial synthesis of D-allulose, an ultra-low calorie rare sugar. However, limited thermostability of DAEs hinders their use at high-temperature production. In this research, hyperthermophilic TI-DAE (Tm = 98.4 ± 0.7 ℃) from Thermotoga sp. was identified via in silico screening. A comparative study of the structure and function of site-directed saturation mutagenesis mutants pinpointed the residue I100 as pivotal in maintaining the high-temperature activity and thermostability of TI-DAE. Employing TI-DAE as a biocatalyst, D-allulose was produced from D-fructose with a conversion rate of 32.5%. Moreover, TI-DAE demonstrated excellent catalytic synergy with glucose isomerase CAGI, enabling the one-step conversion of D-glucose to D-allulose with a conversion rate of 21.6%. This study offers a promising resource for the enzyme engineering of DAEs and a high-performance biocatalyst for industrial D-allulose production.


Assuntos
Thermotoga , Thermotoga/enzimologia , Thermotoga/genética , Carboidratos Epimerases/genética , Carboidratos Epimerases/química , Carboidratos Epimerases/metabolismo , Carboidratos Epimerases/biossíntese , Racemases e Epimerases/genética , Racemases e Epimerases/metabolismo , Racemases e Epimerases/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/biossíntese , Frutose/metabolismo , Frutose/biossíntese , Frutose/química , Estabilidade Enzimática , Biocatálise , Mutagênese Sítio-Dirigida , Temperatura Alta
14.
Int J Biol Macromol ; 267(Pt 1): 131473, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38614185

RESUMO

Actinoplanes utahensis deacylase (AAC)-catalyzed deacylation of echinocandin B (ECB) is a promising method for the synthesis of anidulafungin, the newest of the echinocandin antifungal agents. However, the low activity of AAC significantly limits its practical application. In this work, we have devised a multi-dimensional rational design strategy for AAC, conducting separate analyses on the substrate-binding pocket's volume, curvature, and length. Furthermore, we quantitatively analyzed substrate properties, particularly on hydrophilic and hydrophobic. Accordingly, we tailored the linoleic acid-binding pocket of AAC to accommodate the extended long lipid chain of ECB. By fine-tuning the key residues, the resulting AAC mutants can accommodate the ECB lipid chain with a lower curvature binding pocket. The D53A/I55F/G57M/F154L/Q661L mutant (MT) displayed 331 % higher catalytic efficiency than the wild-type (WT) enzyme. The MT product conversion was 94.6 %, reaching the highest reported level. Utilizing a multi-dimensional rational design for a customized mutation strategy of the substrate-binding pocket is an effective approach to enhance the catalytic efficiency of enzymes in handling complicated substrates.


Assuntos
Equinocandinas , Proteínas Fúngicas , Interações Hidrofóbicas e Hidrofílicas , Equinocandinas/química , Especificidade por Substrato , Sítios de Ligação , Mutação , Modelos Moleculares , Amidoidrolases/química , Amidoidrolases/genética , Amidoidrolases/metabolismo , Ligação Proteica
15.
Biotechnol Adv ; 72: 108352, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38574900

RESUMO

Nitrilases represent a distinct class of enzymes that play a pivotal role in catalyzing the hydrolysis of nitrile compounds, leading to the formation of corresponding carboxylic acids. These enzymatic entities have garnered significant attention across a spectrum of industries, encompassing pharmaceuticals, agrochemicals, and fine chemicals. Moreover, their significance has been accentuated by mounting environmental pressures, propelling them into the forefront of biodegradation and bioremediation endeavors. Nevertheless, the natural nitrilases exhibit intrinsic limitations such as low thermal stability, narrow substrate selectivity, and inadaptability to varying environmental conditions. In the past decade, substantial efforts have been made in elucidating the structural underpinnings and catalytic mechanisms of nitrilase, providing basis for engineering of nitrilases. Significant breakthroughs have been made in the regulation of nitrilases with ideal catalytic properties and application of the enzymes for industrial productions. This review endeavors to provide a comprehensive discourse and summary of recent research advancements related to nitrilases, with a particular emphasis on the elucidation of the structural attributes, catalytic mechanisms, catalytic characteristics, and strategies for improving catalytic performance of nitrilases. Moreover, the exploration extends to the domain of process engineering and the multifarious applications of nitrilases. Furthermore, the future development trend of nitrilases is prospected, providing important guidance for research and application in the related fields.


Assuntos
Aminoidrolases , Nitrilas , Aminoidrolases/genética , Aminoidrolases/química , Catálise , Biodegradação Ambiental
16.
Metabolites ; 14(4)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38668359

RESUMO

Heavy metal pollution poses significant environmental challenges, and understanding how plants and endophytic bacteria interact to mitigate these challenges is of utmost importance. In this study, we investigated the roles of endophytic bacteria, particularly Chryseobacterium and Comamonas, in Leersia hexandra Swartz (L. hexandra) in response to chromium and nickel co-pollution. Our results demonstrated the remarkable tolerance of Chryseobacterium and Comamonas to heavy metals, and their potential to become dominant species in the presence of co-pollution. We observed a close relationship between these endophytic bacteria and the significant differences in metabolites, particularly carbohydrates, flavonoids, and amino acids in L. hexandra. These findings shed light on the potential of endophytic bacteria to promote the production of aspartic acid and other metabolites in plants as a response to abiotic stressors. Furthermore, our study presents a new direction for plant and bioremediation strategies in heavy metal pollution and enhances our understanding of L. hexandra's mechanisms for heavy metal tolerance.

17.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(2): 176-183, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38686713

RESUMO

Objective To evaluate the clinical efficacy and safety of intensive insulin therapy in the patients with acute myocardial infarction and provide guidance for improving the prognosis. Methods The articles involving the randomized controlled trials(RCT)focusing on the effects of intensive versus conventional insulin therapy on the clinical outcomes of the patients with acute myocardial infarction were retrieved from Cochrane,Embase,PubMed,CNKI,Wanfang Data,VIP,and CBM with the time interval from inception to October 2022.The data of each RCT were extracted and used for meta-analysis in RevMan5.4. Results A total of 8 articles were included in this study,involving 726 patients(372 in the intensive insulin group and 354 in the normal insulin group).The meta-analysis results showed that the intensive insulin group had lower incidence of major cardiovascular adverse events (RR=0.53, 95%CI=0.44-0.64, P<0.001), lower all-cause mortality (RR=0.51, 95%CI=0.33-0.78, P=0.002),lower high-sensitivity C-reactive protein level on day 7(WMD=-2.00,95%CI=-2.17- -1.83,P<0.001),higher left ventricular ejection fraction on day 30 (WMD=3.94, 95%CI=2.45-5.43,P<0.001), and higher incidence of hypoglycemia events (RR=2.96, 95%CI=1.12-7.83,P=0.030) than the normal insulin group.There was no significant difference between the two groups in terms of no-reflow event after percutaneous coronary intervention(RR=0.39,95%CI=0.14-1.13,P=0.080). Conclusion Intensive insulin therapy might be associated with more clinical benefits in the patients with acute myocardial infarction,while the conclusion remains to be confirmed by more studies.


Assuntos
Insulina , Infarto do Miocárdio , Humanos , Infarto do Miocárdio/tratamento farmacológico , Insulina/uso terapêutico , Insulina/administração & dosagem , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Proteína C-Reativa
18.
Eur J Nutr ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38687390

RESUMO

PURPOSE: Gastric cancer (GC) is among the leading causes of cancer mortality worldwide. The objective of this study was to investigate the association between dietary fiber intake and GC. METHODS: We pooled data from 11 population or hospital-based case-control studies included in the Stomach Cancer Pooling (StoP) Project, for a total of 4865 histologically confirmed cases and 10,626 controls. Intake of dietary fibers and other dietary factors was collected using food frequency questionnaires. We calculated the odds ratios (OR) and 95% confidence intervals (CI) of the association between dietary fiber intake and GC by using a multivariable logistic regression model adjusted for study site, sex, age, caloric intake, smoking, fruit and vegetable intake, and socioeconomic status. We conducted stratified analyses by these factors, as well as GC anatomical site and histological type. RESULTS: The OR of GC for an increase of one quartile of fiber intake was 0.91 (95% CI: 0.85, 0.97), that for the highest compared to the lowest quartile of dietary fiber intake was 0.72 (95% CI: 0.59, 0.88). Results were similar irrespective of anatomical site and histological type. CONCLUSION: Our analysis supports the hypothesis that dietary fiber intake may exert a protective effect on GC.

19.
Sci Adv ; 10(13): eadl4842, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38552028

RESUMO

The high-capacity advantage of lithium metal anode was compromised by common use of copper as the collector. Furthermore, lithium pulverization associated with "dead" Li accumulation and electrode cracking deteriorates the long-term cyclability of lithium metal batteries, especially under realistic test conditions. Here, we report an ultralight, integrated anode of polyimide-Ag/Li with dual anti-pulverization functionality. The silver layer was initially chemically bonded to the polyimide surface and then spontaneously diffused in Li solid solution and self-evolved into a fully lithiophilic Li-Ag phase, mitigating dendrites growth or dead Li. Further, the strong van der Waals interaction between the bottommost Li-Ag and polyimide affords electrode structural integrity and electrical continuity, thus circumventing electrode pulverization. Compared to the cutting-edge anode-free cells, the batteries pairing LiNi0.8Mn0.1Co0.1O2 with polyimide-Ag/Li afford a nearly 10% increase in specific energy, with safer characteristics and better cycling stability under realistic conditions of 1× excess Li and high areal-loading cathode (4 milliampere hour per square centimeter).

20.
Org Biomol Chem ; 22(15): 3009-3018, 2024 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-38529785

RESUMO

Catalytic activity is undoubtedly a key focus in enzyme engineering. The complicated reaction conditions hinder some enzymes from industrialization even though they have relatively promising activity. This has occurred to some dehydrogenases. Hydroxysteroid dehydrogenases (HSDHs) specifically catalyze the conversion between hydroxyl and keto groups, and hold immense potential in the synthesis of steroid medicines. We underscored the importance of 7α-HSDH activity, and analyzed the overall robustness and underlying mechanisms. Employing a high-throughput screening approach, we comprehensively assessed a mutation library, and obtained a mutant with enhanced enzymatic activity and overall stability/tolerance. The superior mutant (I201M) was identified to harbor improved thermal stability, substrate susceptibility, cofactor affinity, as well as the yield. This mutant displayed a 1.88-fold increase in enzymatic activity, a 1.37-fold improvement in substrate tolerance, and a 1.45-fold increase in thermal stability when compared with the wild type (WT) enzyme. The I201M mutant showed a 2.25-fold increase in the kcat/KM ratio (indicative of a stronger binding affinity for the cofactor). This mutant did not exhibit the highest enzyme activity compared with all the tested mutants, but these improved characteristics contributed synergistically to the highest yield. When a substrate at 100 mM was present, the 24 h yield by I201M reached 89.7%, significantly higher than the 61.2% yield elicited by the WT enzyme. This is the first report revealing enhancement of the catalytic efficiency, cofactor affinity, substrate tolerance, and thermal stability of NAD(H)-dependent 7α-HSDH through a single-point mutation. The mutated enzyme reached the highest enzymatic activity of 7α-HSDH ever reported. High enzymatic activity is undoubtedly crucial for enabling the industrialization of an enzyme. Our findings demonstrated that, when compared with other mutants boasting even higher enzymatic activity, mutants with excellent overall robustness were superior for industrial applications. This principle was exemplified by highly active enzymes such as 7α-HSDH.


Assuntos
Hidroxiesteroide Desidrogenases , Mutação Puntual , Hidroxiesteroide Desidrogenases/genética , Hidroxiesteroide Desidrogenases/metabolismo , Mutação , Catálise , Cinética
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