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1.
Nature ; 631(8022): 884-890, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39020178

RESUMO

Plastic production reached 400 million tons in 2022 (ref. 1), with packaging and single-use plastics accounting for a substantial amount of this2. The resulting waste ends up in landfills, incineration or the environment, contributing to environmental pollution3. Shifting to biodegradable and compostable plastics is increasingly being considered as an efficient waste-management alternative4. Although polylactide (PLA) is the most widely used biosourced polymer5, its biodegradation rate under home-compost and soil conditions remains low6-8. Here we present a PLA-based plastic in which an optimized enzyme is embedded to ensure rapid biodegradation and compostability at room temperature, using a scalable industrial process. First, an 80-fold activity enhancement was achieved through structure-based rational engineering of a new hyperthermostable PLA hydrolase. Second, the enzyme was uniformly dispersed within the PLA matrix by means of a masterbatch-based melt extrusion process. The liquid enzyme formulation was incorporated in polycaprolactone, a low-melting-temperature polymer, through melt extrusion at 70 °C, forming an 'enzymated' polycaprolactone masterbatch. Masterbatch pellets were integrated into PLA by melt extrusion at 160 °C, producing an enzymated PLA film (0.02% w/w enzyme) that fully disintegrated under home-compost conditions within 20-24 weeks, meeting home-composting standards. The mechanical and degradation properties of the enzymated film were compatible with industrial packaging applications, and they remained intact during long-term storage. This innovative material not only opens new avenues for composters and biomethane production but also provides a feasible industrial solution for PLA degradation.


Assuntos
Plásticos Biodegradáveis , Biodegradação Ambiental , Enzimas Imobilizadas , Hidrolases , Poliésteres , Engenharia de Proteínas , Plásticos Biodegradáveis/química , Plásticos Biodegradáveis/metabolismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Hidrolases/metabolismo , Hidrolases/química , Poliésteres/química , Poliésteres/metabolismo , Solo/química , Temperatura , Estabilidade Enzimática , Compostagem
2.
Proc Natl Acad Sci U S A ; 121(30): e2403460121, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39008666

RESUMO

Autonomous nanorobots represent an advanced tool for precision therapy to improve therapeutic efficacy. However, current nanorobotic designs primarily rely on inorganic materials with compromised biocompatibility and limited biological functions. Here, we introduce enzyme-powered bacterial outer membrane vesicle (OMV) nanorobots. The immobilized urease on the OMV membrane catalyzes the decomposition of bioavailable urea, generating effective propulsion for nanorobots. This OMV nanorobot preserves the unique features of OMVs, including intrinsic biocompatibility, immunogenicity, versatile surface bioengineering for desired biofunctionalities, capability of cargo loading and protection. We present OMV-based nanorobots designed for effective tumor therapy by leveraging the membrane properties of OMVs. These involve surface bioengineering of robotic body with cell-penetrating peptide for tumor targeting and penetration, which is further enhanced by active propulsion of nanorobots. Additionally, OMV nanorobots can effectively safeguard the loaded gene silencing tool, small interfering RNA (siRNA), from enzymatic degradation. Through systematic in vitro and in vivo studies using a rodent model, we demonstrate that these OMV nanorobots substantially enhanced siRNA delivery and immune stimulation, resulting in the utmost effectiveness in tumor suppression when juxtaposed with static groups, particularly evident in the orthotopic bladder tumor model. This OMV nanorobot opens an inspiring avenue to design advanced medical robots with expanded versatility and adaptability, broadening their operation scope in practical biomedical domains.


Assuntos
Membrana Externa Bacteriana , Animais , Humanos , Membrana Externa Bacteriana/metabolismo , Camundongos , Robótica/métodos , Urease/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo
3.
Nat Chem Biol ; 20(6): 732-741, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38321209

RESUMO

Glycosylation is a critical post-translational protein modification that affects folding, half-life and functionality. Glycosylation is a non-templated and heterogeneous process because of the promiscuity of the enzymes involved. We describe a platform for sequential glycosylation reactions for tailored sugar structures (SUGAR-TARGET) that allows bespoke, controlled N-linked glycosylation in vitro enabled by immobilized enzymes produced with a one-step immobilization/purification method. We reconstruct a reaction cascade mimicking a glycosylation pathway where promiscuity naturally exists to humanize a range of proteins derived from different cellular systems, yielding near-homogeneous glycoforms. Immobilized ß-1,4-galactosyltransferase is used to enhance the galactosylation profile of three IgGs, yielding 80.2-96.3% terminal galactosylation. Enzyme recycling is demonstrated for a reaction time greater than 80 h. The platform is easy to implement, modular and reusable and can therefore produce homogeneous glycan structures derived from various hosts for functional and clinical evaluation.


Assuntos
Enzimas Imobilizadas , Galactosiltransferases , Glicosilação , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Humanos , Galactosiltransferases/metabolismo , Galactosiltransferases/química , Polissacarídeos/metabolismo , Polissacarídeos/química , Processamento de Proteína Pós-Traducional
4.
Nano Lett ; 24(11): 3404-3412, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38451852

RESUMO

Assembling metal-organic frameworks (MOFs) into ordered multidimensional porous superstructures promises the encapsulation of enzymes for heterogeneous biocatalysts. However, the full potential of this approach has been limited by the poor stability of enzymes and the uncontrolled assembly of MOF nanoparticles onto suitable supports. In this study, a novel and exceptionally robust Ni-imidazole-based MOF was synthesized in water at room temperature, enabling in situ enzyme encapsulation. Based on this MOF platform, we developed a DNA-directed assembly strategy to achieve the uniform placement of MOF nanoparticles onto bacterial cellulose nanofibers, resulting in a distinctive "branch-fruit" structure. The resulting hybrid materials demonstrated remarkable versatility across various catalytic systems, accommodating natural enzymes, nanoenzymes, and multienzyme cascades, thus showcasing enormous potential as universal microbioreactors. Furthermore, the hierarchical composites facilitated rapid diffusion of the bulky substrate while maintaining the enzyme stability, with ∼3.5-fold higher relative activity compared to the traditional enzyme@MOF immobilized in bacterial cellulose nanofibers.


Assuntos
Enzimas Imobilizadas , Nanofibras , Enzimas Imobilizadas/química , Celulose , Frutas , DNA/química
5.
Nano Lett ; 24(15): 4682-4690, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38563501

RESUMO

Multienzyme assemblies mediated by multivalent interaction play a crucial role in cellular processes. However, the three-dimensional (3D) programming of an enzyme complex with defined enzyme activity in vitro remains unexplored, primarily owing to limitations in precisely controlling the spatial topological configuration. Herein, we introduce a nanoscale 3D enzyme assembly using a tetrahedral DNA framework (TDF), enabling the replication of spatial topological configuration and maintenance of an identical edge-to-edge distance akin to natural enzymes. Our results demonstrate that 3D nanoscale enzyme assemblies in both two-enzyme systems (glucose oxidase (GOx)/horseradish peroxidase (HRP)) and three-enzyme systems (amylglucosidase (AGO)/GOx/HRP) lead to enhanced cascade catalytic activity compared to the low-dimensional structure, resulting in ∼5.9- and ∼7.7-fold enhancements over homogeneous diffusional mixtures of free enzymes, respectively. Furthermore, we demonstrate the enzyme assemblies for the detection of the metabolism biomarkers creatinine and creatine, achieving a low limit of detection, high sensitivity, and broad detection range.


Assuntos
Enzimas Imobilizadas , Glucose Oxidase , Enzimas Imobilizadas/química , Peroxidase do Rábano Silvestre/química , Glucose Oxidase/química , DNA/química
6.
J Am Chem Soc ; 146(13): 9112-9123, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38500441

RESUMO

Recent advances have demonstrated the promise of complex multicomponent polymeric supports to enable supra-biological enzyme performance. However, the discovery of such supports has been limited by time-consuming, low-throughput synthesis and screening. Here, we describe a novel combinatorial and high-throughput platform that enables rapid screening of complex and heterogeneous copolymer brushes as enzyme immobilization supports, named combinatorial high-throughput enzyme support screening (CHESS). Using a 384-well plate format, we synthesized arrays of three-component polymer brushes in the microwells using photoactivated surface-initiated polymerization and immobilized enzymes in situ. The utility of CHESS to identify optimal immobilization supports under thermally and chemically denaturing conditions was demonstrated usingBacillus subtilisLipase A (LipA). The identification of supports with optimal compositions was validated by immobilizing LipA on polymer-brush-modified biocatalyst particles. We further demonstrated that CHESS could be used to predict the optimal composition of polymer brushes a priori for the previously unexplored enzyme, alkaline phosphatase (AlkP). Our findings demonstrate that CHESS represents a predictable and reliable platform for dramatically accelerating the search of chemical compositions for immobilization supports and further facilitates the discovery of biocompatible and stabilizing materials.


Assuntos
Enzimas Imobilizadas , Ensaios de Triagem em Larga Escala , Enzimas Imobilizadas/química , Polímeros/química
7.
J Am Chem Soc ; 146(1): 858-867, 2024 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-38159294

RESUMO

Recombinant enzymes have gained prominence due to their diverse functionalities and specificity and are often a greener alternative in biocatalysis. This context makes purifying recombinant enzymes from host cells and other impurities crucial. The primary goal is to isolate the pure enzyme of interest and ensure its stability under ambient conditions. Covalent organic frameworks (COFs), renowned for their well-ordered structure and permeability, offer a promising approach for purifying histidine-tagged (His-tagged) enzymes. Furthermore, immobilizing enzymes within COFs represents a growing field in heterogeneous biocatalysis. In this study, we have developed a flow-based technology utilizing a nickel-infused covalent organic framework (Ni-TpBpy COF) to combine two distinct processes: the purification of His-tagged enzymes and the immobilization of enzymes simultaneously. Our work primarily focuses on the purification of three His-tagged enzymes ß-glucosidase, cellobiohydrolase, and endoglucanase as well as two proteins with varying molecular weights, namely, green fluorescent protein (27 kDa) and BG Rho (88 kDa). We employed Ni-TpBpy as a column matrix to showcase the versatility of our system. Additionally, we successfully obtained a Ni-TpBpy COF immobilized with enzymes, which can serve as a heterogeneous catalyst for the hydrolysis of p-nitrophenyl-ß-d-glucopyranoside and carboxymethylcellulose. These immobilized enzymes demonstrated catalytic activity comparable to that of their free counterparts, with the added advantages of recyclability and enhanced stability under ambient conditions for an extended period, ranging from 60 to 90 days. This contrasts with the free enzymes, which do not maintain their activity as effectively over time.


Assuntos
Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Biocatálise , Enzimas Imobilizadas/química , Indicadores e Reagentes , Catálise
8.
J Am Chem Soc ; 146(30): 20778-20787, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39013149

RESUMO

The forward design of in vitro enzymatic reaction networks (ERNs) requires a detailed analysis of network kinetics and potentially hidden interactions between the substrates and enzymes. Although flow chemistry allows for a systematic exploration of how the networks adapt to continuously changing conditions, the analysis of the reaction products is often a bottleneck. Here, we report on the interface between a continuous stirred-tank reactor, in which an immobilized enzymatic network made of 12 enzymes is compartmentalized, and an ion mobility-mass spectrometer. Feeding uniformly 13C-labeled inputs to the enzymatic network generates all isotopically labeled reaction intermediates and products, which are individually detected by ion mobility-mass spectrometry (IMS-MS) based on their mass-to-charge ratios and inverse ion mobilities. The metabolic flux can be continuously and quantitatively monitored by diluting the ERN output with nonlabeled standards of known concentrations. The real-time quantitative data obtained by IMS-MS are then harnessed to train a model of network kinetics, which proves sufficiently predictive to control the ERN output after a single optimally designed experiment. The high resolution of the time-course data provided by this approach is an important stepping stone to design and control sizable and intricate ERNs.


Assuntos
Enzimas Imobilizadas , Espectrometria de Massas , Espectrometria de Massas/métodos , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Cinética , Espectrometria de Mobilidade Iônica/métodos
9.
J Am Chem Soc ; 146(25): 17189-17200, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38864358

RESUMO

Spatial immobilization of fragile enzymes using a nanocarrier is an efficient means to design heterogeneous biocatalysts, presenting superior stability and recyclability to pristine enzymes. An immobilized enzyme, however, usually compromises its catalytic activity because of inevasible mass transfer issues and the unfavorable conformation changes in a confined environment. Here, we describe a synergetic metal-organic framework pore-engineering strategy to trap lipase (an important hydrolase), which confers lipase-boosted stability and activity simultaneously. The hierarchically porous NU-1003, featuring interconnected mesopore and micropore channels, is precisely modified by chain-adjustable fatty acids on its mesopore channel, into which lipase is trapped. The interconnected pore structure ensures efficient communication between trapped lipase and exterior media, while the fatty acid-mediated hydrophobic pore can activate the opening conformation of lipase by interfacial interaction. Such dual pore compartmentalization and hydrophobization activation effects render the catalytic center of trapped lipase highly accessible, resulting in 1.57-fold and 2.46-fold activities as native lipase on ester hydrolysis and enantioselective catalysis. In addition, the feasibility of these heterogeneous biocatalysts for kinetic resolution of enantiomer is also validated, showing much higher efficiency than native lipase.


Assuntos
Estabilidade Enzimática , Enzimas Imobilizadas , Interações Hidrofóbicas e Hidrofílicas , Lipase , Lipase/química , Lipase/metabolismo , Porosidade , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Estruturas Metalorgânicas/química , Hidrólise , Biocatálise
10.
J Am Chem Soc ; 146(28): 18817-18822, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38968608

RESUMO

NAD(H)-dependent enzymes play a crucial role in the biosynthesis of pharmaceuticals and fine chemicals, but the limited recyclability of the NAD(H) cofactor hinders its more general application. Here, we report the generation of mechano-responsive PEI-modified Cry3Aa protein crystals and their use for NADH recycling over multiple reaction cycles. For demonstration of its practical utility, a complementary Cry3Aa protein particle containing genetically encoded and co-immobilized formate dehydrogenase for NADH regeneration and leucine dehydrogenase for catalyzing the NADH-dependent l-tert-leucine (l-tert-Leu) biosynthesis has been produced. When combined with the PEI-modified Cry3Aa crystal, the resultant reaction system could be used for the efficient biosynthesis of l-tert-Leu for up to 21 days with a 10.5-fold improvement in the NADH turnover number.


Assuntos
Formiato Desidrogenases , NAD , NAD/metabolismo , NAD/química , Formiato Desidrogenases/metabolismo , Formiato Desidrogenases/química , Leucina Desidrogenase/metabolismo , Leucina Desidrogenase/química , Cristalização , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Modelos Moleculares
11.
Anal Chem ; 96(22): 9228-9235, 2024 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-38779801

RESUMO

Open-tubular immobilized enzyme microreactors (OT-IMERs) are some of the most widely used enzyme reaction devices due to the advantages of simple preparation and fast sample processing. However, the traditional approaches for OT-IMERs preparation had some defects such as limited enzyme loading amount, susceptibility to complex sample interference, and less stability. Here, we report a strategy for the preparation of highly active and stable OT-IMERs, in which the single-stranded DNA-enzyme composites were immobilized in capillaries and then encapsulated in situ in the capillaries via zeolitic imidazolate frameworks (ZIF-L). The phosphate groups of the DNA adjusted the surface potential of the enzyme to negative values, which could attract cations, such as Zn2+, to promote the formation of ZIF-L for enzyme encapsulation. Using chymotrypsin (ChT) as a model enzyme, the prepared ChT@ZIF-L-IMER has higher activity and better affinity than the free enzyme and ChT-IMER. Moreover, the thermal stability, pH stability, and organic solvent stability of ChT@ZIF-L-IMER were much higher than those of free enzyme and ChT-IMER. Furthermore, the activity of ChT@ZIF-L-IMER was much higher than that of ChT-IMER after ten consecutive reactions. To demonstrate the versatility of this preparation method, we replaced ChT with glucose oxidase (GOx). The stability of GOx@ZIF-L-IMER was also experimentally demonstrated to be superior to that of GOx and GOx-IMER. Finally, ChT@ZIF-L-IMER was used for proteolytic digestion analysis. The results showed that ChT@ZIF-L-IMER had a short digestion time and high digestive efficiency compared with the free enzyme. The present study broadened the synthesis method of OT-IMERs, effectively integrating the advantages of metal-organic frameworks and IMER, and the prepared OT-IMERs significantly improved enzyme stability. All of the results indicated that the IMER prepared by this method had a broad application prospect in capillary electrophoresis-based high-performance enzyme analysis.


Assuntos
Quimotripsina , Estabilidade Enzimática , Enzimas Imobilizadas , Imidazóis , Zeolitas , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Zeolitas/química , Imidazóis/química , Quimotripsina/metabolismo , Quimotripsina/química , Estruturas Metalorgânicas/química , Concentração de Íons de Hidrogênio
12.
Anal Chem ; 96(41): 16244-16251, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39353585

RESUMO

The use of miniaturized probes opens a new dimension in the analysis of (bio)chemical processes, enabling the possibility to perform measurements with local resolution. In addition, multiparametric measurements are highly valuable for a holistic understanding of the investigated process. Therefore, different strategies have been suggested for simultaneous local measurements of various parameters. Electroanalytical methods are a powerful strategy in this direction. However, they have been mainly restricted to coupling concurrent independent measurements with different miniaturized probes. Here, we present an enzymatic microbiosensor for the simultaneous detection of O2 and pH. The sensing strategy is based on the pH-dependent bioelectrocatalytic process associated with O2 reduction at a gold microelectrode modified with a multicopper oxidase. After initial investigations of the bioelectrocatalytic reaction over gold macroelectrodes, the fabrication and characterization of micrometer-sized probes are presented. The microbioelectrode exhibits a linear current increase with O2 concentration extending to 17.2 mg L-1, with a sensitivity of (5.56 ± 0.13) nA L mg-1 and a limit of detection of (0.5 ± 0.3) mg L-1. Moreover, a linear response allowing pH detection is obtained between pH 5.2 and 7.5 with a slope of -(47 ± 8) mV per pH unit. In addition, two proof-of-concept analytical examples are shown, demonstrating the capability of the developed sensing system for simultaneous local measurements of O2 and pH. Compared with other miniaturized probes reported before for simultaneous detection, our strategy stands out as the two investigated parameters are acquired from the very same measurement. This strategy greatly simplifies the analytical setup and for the first time provides truly simultaneous local detection in the micrometer scale.


Assuntos
Ouro , Microeletrodos , Oxigênio , Concentração de Íons de Hidrogênio , Oxigênio/química , Oxigênio/análise , Ouro/química , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Oxirredutases/metabolismo , Oxirredutases/química
13.
Anal Chem ; 96(28): 11549-11556, 2024 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-38958207

RESUMO

Human-borne acetone is a potent marker of lipid metabolism. Here, an enzyme immobilization method for secondary alcohol dehydrogenase (S-ADH), which is suitable for highly sensitive and selective biosensing of acetone, was developed, and then its applicability was demonstrated for spatiotemporal imaging of concentration distribution. After various investigations, S-ADH-immobilized meshes could be prepared with less than 5% variation by cross-linking S-ADH with glutaraldehyde on a cotton mesh at 40 °C for 15 min. Furthermore, high activity was obtained by adjusting the concentration of the coenzyme nicotinamide adenine dinucleotide (NADH) solution added to the S-ADH-immobilized mesh to 500 µM and the solvent to a potassium phosphate buffer solution at pH 6.5. The gas imaging system using the S-ADH-immobilized mesh was able to image the decrease in NADH fluorescence (ex 340 nm, fl 490 nm) caused by the catalytic reaction of S-ADH and the acetone distribution in the concentration range of 0.1-10 ppm-v, including the breath concentration of healthy people at rest. The exhaled breath of two healthy subjects at 6 h of fasting was quantified as 377 and 673 ppb-v, which were consistent with the values quantified by gas chromatography-mass spectrometry.


Assuntos
Acetona , Testes Respiratórios , Enzimas Imobilizadas , Acetona/análise , Acetona/química , Humanos , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Técnicas Biossensoriais , Oxirredutases do Álcool/química , Oxirredutases do Álcool/metabolismo , Gases/química , Gases/análise , Expiração , NAD/análise , NAD/química , NAD/metabolismo
14.
Anal Chem ; 96(41): 16355-16361, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39370725

RESUMO

Organic photoelectrochemical transistor (OPECT) has emerged as a promising technique for biomolecule detection, yet its operational rationale remains limited due to its short development time. This study introduces a stable tandem catalysis protocol by synergizing the enzyme-incorporated metal-organic frameworks (E-MOFs) with polyoxometalate (POM) nanozyme for sensitive OPECT bioanalysis. The zeolitic imidazolate framework-8 (ZIF-8) acts as the skeleton to protect the encapsulated glucose oxidase (GOx), allowing the stable catalytic generation of H2O2. With peroxidase-like activity, a phosphotungstic acid hydrate (PW12) is then able to utilize the H2O2 to induce the biomimetic precipitation on the photogate, ultimately resulting in the altered device characteristics for quantitative detection. This work reveals the potential and versatility of an engineered enzymatic system as a key enabler to achieve novel OPECT bioanalysis, which is believed to offer a feasible framework to explore new operational rationale in optoelectronic and bioelectronic detection.


Assuntos
Técnicas Eletroquímicas , Glucose Oxidase , Peróxido de Hidrogênio , Estruturas Metalorgânicas , Compostos de Tungstênio , Estruturas Metalorgânicas/química , Compostos de Tungstênio/química , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/análise , Catálise , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Técnicas Biossensoriais , Processos Fotoquímicos , Transistores Eletrônicos
15.
Small ; 20(30): e2312220, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38344893

RESUMO

Enzymatic activity depends on and can therefore be regulated by temperature. Selective modulation of the activity of different enzymes in one reaction pot would require temperature control local to each type of enzyme. It has been suggested previously that immobilization of enzyme on magnetic nanoparticles and exposing them to alternating magnetic field can enhance the reaction rate. This enhancement has been explained as being mediated by temperature increase caused by dissipation of the absorbed field energy in the form of heat. However, the possibility of spatially limiting this temperature increase on the microscale has been questioned. Here, it is investigated whether an activity enhancement of the enzyme sucrose phosphorylase immobilized on magnetic beads can be achieved, how this effect is related to the increase in temperature, and whether temperature differences within one reaction pot could be generated in this way. It is found that alternating magnetic field stimulation leads to increased enzymatic activity fully attributable to the increase of bulk temperature. Both theoretical analysis and experimental data indicate that no local heating near the particle surface takes place. It is further concluded that relevant increase of surface temperature can be obtained only with macroscopic, millimeter-sized, magnetic particles.


Assuntos
Ativação Enzimática , Temperatura , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Campos Magnéticos , Glucosiltransferases/metabolismo
16.
Chembiochem ; 25(11): e202400086, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38618870

RESUMO

Sustainable biocatalysis syntheses have gained considerable popularity over the years. However, further optimizations - notably to reduce costs - are required if the methods are to be successfully deployed in a range of areas. As part of this drive, various enzyme immobilization strategies have been studied, alongside process intensification from batch to continuous production. The flow bioreactor portfolio mainly ranges between packed bed reactors and wall-immobilized enzyme miniaturized reactors. Because of their simplicity, packed bed reactors are the most frequently encountered at lab-scale. However, at industrial scale, the growing pressure drop induced by the increase in equipment size hampers their implementation for some applications. Wall-immobilized miniaturized reactors require less pumping power, but a new problem arises due to their reduced enzyme-loading capacity. This review starts with a presentation of the current technology portfolio and a reminder of the metrics to be applied with flow bioreactors. Then, a benchmarking of the most recent relevant works is presented. The scale-up perspectives of the various options are presented in detail, highlighting key features of industrial requirements. One of the main objectives of this review is to clarify the strategies on which future study should center to maximize the performance of wall-immobilized enzyme reactors.


Assuntos
Biocatálise , Reatores Biológicos , Enzimas Imobilizadas , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Miniaturização
17.
Chembiochem ; 25(17): e202400339, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-38801661

RESUMO

Utilizing covalent organic frameworks (COFs) as porous supports to encapsulate enzyme represents an advanced strategy for constructing COFs biocatalysts, which has inspired numerous interests across various applications. As the structural advantages including ultrastable covalent-bonded linkage, tailorable pore structure, and metal-free biocompatibility, the resultant enzyme-COFs biocatalysts showcase functional enhancement in catalytic activity, chemical stability, long-term durability, and recyclability. This Concept describes the recent advances in the methodological strategies for engineering the COFs biocatalysts, with specific emphasis on the pore entrapment and in situ encapsulation strategies. The structural advantages of the COFs hybrid biocatalysts for organic synthesis, environment- and energy-associated applications are also canvassed. Additionally, the remaining challenges and the forward-looking directions in this field are also discussed. We believe that this Concept can offer useful methodological guidance for developing active and robust COFs biocatalysts.


Assuntos
Biocatálise , Enzimas Imobilizadas , Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/metabolismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Porosidade , Enzimas/metabolismo , Enzimas/química
18.
Chembiochem ; 25(15): e202400346, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38775416

RESUMO

Multi-enzyme cascade catalysis has become an important technique for chemical reactions used in manufacturing and scientific study. In this research, we designed a four-enzyme integrated catalyst and used it to catalyse the deracemization reaction of cyclic chiral amines, where monoamine oxidase (MAO) catalyses the enantioselective oxidation of 1-methyl-1,2,3,4-tetrahydroisoquinoline (MTQ), imine reductase (IRED) catalyses the stereo selective reduction of 1-methyl-3,4-dihydroisoquinoline (MDQ), formate dehydrogenase (FDH) is used for the cyclic regeneration of cofactors, and catalase (CAT) is used for decomposition of oxidative reactions. The four enzymes were immobilized via polydopamine (PDA)-encapsulated dendritic organosilica nanoparticles (DONs) as carriers, resulting in the amphiphilic core-shell catalysts. The hydrophilic PDA shell ensures the dispersion of the catalyst in water, and the hydrophobic DON core creates a microenvironment with the spatial confinement effect of the organic substrate and the preconcentration effect to enhance the stability of the enzymes and the catalytic efficiency. The core-shell structure improves the stability and reusability of the catalyst and rationally arranges the position of different enzymes according to the reaction sequence to improve the cascade catalytic performance and cofactor recovery efficiency.


Assuntos
Aminas , Monoaminoxidase , Polímeros , Aminas/química , Aminas/metabolismo , Monoaminoxidase/metabolismo , Monoaminoxidase/química , Polímeros/química , Polímeros/metabolismo , Formiato Desidrogenases/metabolismo , Formiato Desidrogenases/química , Catalase/química , Catalase/metabolismo , Indóis/química , Indóis/metabolismo , Estereoisomerismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Oxirredução , Nanopartículas/química , Biocatálise , Compostos de Organossilício/química , Oxirredutases/metabolismo , Oxirredutases/química , Catálise
19.
Chembiochem ; 25(19): e202400178, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38742869

RESUMO

Natural and pure p-coumaric acid has valuable applications, and it can be produced via bioprocessing. However, fermentation processes have so far been unable to provide sufficient production metrics, while a biocatalytic process decoupling growth and production historically showed much promise. This biocatalytic process is revisited in order to tackle product inhibition of the key enzyme tyrosine ammonia lyase. In situ product removal is proposed as a possible solution, and a polymer/salt aqueous two-phase system is identified as a suitable system for extraction of p-coumaric acid from an alkaline solution, with a partition coefficient of up to 13. However, a 10 % salt solution was found to reduce tyrosine ammonia lyase activity by 19 %, leading to the need for a more dilute system. The cloud points of two aqueous two-phase systems at 40 °C and pH 10 were found to be 3.8 % salt and 9.5 % polymer, and a 5 % potassium phosphate and 12.5 % poly(ethylene glycol-ran-propylene glycol) mW~2500 system was selected for in situ product removal. An immobilized tyrosine ammonia lyase biocatalyst in this aqueous two-phase system produced up to 33 g/L p-coumaric acid within 24 hours, a 1.9-fold improvement compared to biocatalysis without in situ product removal.


Assuntos
Amônia-Liases , Biocatálise , Ácidos Cumáricos , Propionatos , Ácidos Cumáricos/química , Ácidos Cumáricos/metabolismo , Amônia-Liases/metabolismo , Amônia-Liases/química , Propionatos/química , Propionatos/metabolismo , Enzimas Imobilizadas/metabolismo , Enzimas Imobilizadas/química , Concentração de Íons de Hidrogênio , Fosfatos/metabolismo , Fosfatos/química , Propilenoglicóis/química , Propilenoglicóis/metabolismo , Polietilenoglicóis/química , Polietilenoglicóis/metabolismo , Compostos de Potássio
20.
Chembiochem ; 25(12): e202400147, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629211

RESUMO

Chiral alcohols are not only important building blocks of various bioactive natural compounds and pharmaceuticals, but can serve as synthetic precursors for other valuable organic chemicals, thus the synthesis of these products is of great importance. Bio-catalysis represents one effective way to obtain these molecules, however, the weak stability and high cost of enzymes often hinder its broad application. In this work, we designed a biological nanoreactor by embedding alcohol dehydrogenase (ADH) and glucose dehydrogenase (GDH) in metal-organic-framework ZIF-8. The biocatalyst ADH&GDH@ZIF-8 could be applied to the asymmetric reduction of a series of ketones to give chiral alcohols in high yields (up to 99 %) and with excellent enantioselectivities (>99 %). In addition, the heterogeneous biocatalyst could be recycled and reused at least four times with slight activity decline. Moreover, E. coli containing ADH and GDH was immobilized by ZIF-8 to form biocatalyst E. coli@ZIF-8, which also exhibits good catalytic behaviours. Finally, the chiral alcohols are further converted to marketed drugs (R)-Fendiline, (S)-Rivastigmine and NPS R-568 respectively.


Assuntos
Álcool Desidrogenase , Biocatálise , Enzimas Imobilizadas , Escherichia coli , Glucose 1-Desidrogenase , Cetonas , Estruturas Metalorgânicas , Álcool Desidrogenase/metabolismo , Álcool Desidrogenase/química , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/metabolismo , Cetonas/química , Cetonas/metabolismo , Enzimas Imobilizadas/metabolismo , Enzimas Imobilizadas/química , Escherichia coli/enzimologia , Escherichia coli/metabolismo , Glucose 1-Desidrogenase/metabolismo , Glucose 1-Desidrogenase/química , Oxirredução , Estereoisomerismo
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