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Aricov L, Precupas A, Tudose M, Baltag D, Trică B, Sandu R, Leonties AR. Trametes versicolor laccase activity modulated by the interaction with gold nanoparticles. ENVIRONMENTAL RESEARCH 2023; 237:116920. [PMID: 37597828 DOI: 10.1016/j.envres.2023.116920] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 06/08/2023] [Accepted: 08/17/2023] [Indexed: 08/21/2023]
Abstract
In this study, the impact of gold nanoparticles (AuNPs) on the structure and activity of laccase from Trametes versicolor (Lc) was described. Fluorescence experiments revealed that AuNPs efficiently quench Lc's tryptophan fluorescence by a static and dynamic process. By using differential scanning microcalorimetry and circular dichroism spectroscopy, it was determined how the concentration of nanoparticles and the composition of the medium affected the secondary structure of Lc. The data revealed that upon binding with AuNPs, conformational changes take place mainly in presence of high amounts of nanoparticles. The complex kinetic analysis unveiled the Lc activity enhancement at low concentrations of AuNPs as opposed to the concentrated regime, where it can be reduced by up to 55%. The Michaelis-Menten tests highlighted that the activity of the biocatalyst is closely related to the concentration of AuNPs, while the Selwyn analysis demonstrated that even in a concentrated regime of Lc it is not deactivated regardless of the amount of AuNPs added. The thermal parameters improved by twofold in the presence of low AuNPs concentration, whereas the activation energy increased with AuNPs content, implying that not all collisions are beneficial to the enzyme structure. The effect of AuNPs on the decomposition of a recalcitrant dye (naphthol green B, NG) by Lc was also evaluated, and the Michaelis-Menten model revealed that only the high AuNPs content influenced negatively the Lc activity. The isothermal titration calorimetry revealed that hydrogen bonds are the main intermolecular forces between Lc and AuNPs, while electrostatic interactions are responsible for NG adsorption to AuNPs. The results of the docking analysis show the binding of NG near the copper T1 site of Lc with hydrogen bonds, electrostatic and hydrophobic interactions. The findings of this work provide important knowledge for laccase-based bio-nanoconjugates and their use in the field of environmental remediation.
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Affiliation(s)
- Ludmila Aricov
- "Ilie Murgulescu" Institute of Physical Chemistry, Romanian Academy, Spl. Independentei 202, 060021, Bucharest, Romania
| | - Aurica Precupas
- "Ilie Murgulescu" Institute of Physical Chemistry, Romanian Academy, Spl. Independentei 202, 060021, Bucharest, Romania.
| | - Madalina Tudose
- "Ilie Murgulescu" Institute of Physical Chemistry, Romanian Academy, Spl. Independentei 202, 060021, Bucharest, Romania
| | - Dragos Baltag
- Department of Physical Chemistry, Faculty of Chemistry, University of Bucharest, Bd. Elisabeta 4-12, 030018, Bucharest, Romania; National Institute for Research and Development in Chemistry and Petrochemistry - ICECHIM, Spl. Independentei 202, 060021, Bucharest, Romania
| | - Bogdan Trică
- National Institute for Research and Development in Chemistry and Petrochemistry - ICECHIM, Spl. Independentei 202, 060021, Bucharest, Romania
| | - Romica Sandu
- "Ilie Murgulescu" Institute of Physical Chemistry, Romanian Academy, Spl. Independentei 202, 060021, Bucharest, Romania
| | - Anca Ruxandra Leonties
- "Ilie Murgulescu" Institute of Physical Chemistry, Romanian Academy, Spl. Independentei 202, 060021, Bucharest, Romania.
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2
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Imam H, Hill K, Reid A, Mix S, Marr PC, Marr AC. Supramolecular Ionic Liquid Gels for Enzyme Entrapment. ACS SUSTAINABLE CHEMISTRY & ENGINEERING 2023; 11:6829-6837. [PMID: 37180026 PMCID: PMC10170508 DOI: 10.1021/acssuschemeng.3c00517] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 04/21/2023] [Indexed: 05/15/2023]
Abstract
Reported herein is an entrapment method for enzyme immobilization that does not require the formation of new covalent bonds. Ionic liquid supramolecular gels are formed containing enzymes that can be shaped into gel beads and act as recyclable immobilized biocatalysts. The gel was formed from two components, a hydrophobic phosphonium ionic liquid and a low molecular weight gelator derived from the amino acid phenylalanine. Gel-entrapped lipase from Aneurinibacillus thermoaerophilus was recycled for 10 runs over 3 days without loss of activity and retained activity for at least 150 days. The procedure does not form covalent bonds upon gel formation, which is supramolecular, and no bonds are formed between the enzyme and the solid support.
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Affiliation(s)
- Hasan
T. Imam
- School
of Chemistry and Chemical Engineering, Queen’s
University Belfast, UK, David Keir Building, Stranmillis Road, Belfast, Northern Ireland, United Kingdom BT9 5AG
| | - Kyle Hill
- School
of Chemistry and Chemical Engineering, Queen’s
University Belfast, UK, David Keir Building, Stranmillis Road, Belfast, Northern Ireland, United Kingdom BT9 5AG
| | - Andrew Reid
- School
of Chemistry and Chemical Engineering, Queen’s
University Belfast, UK, David Keir Building, Stranmillis Road, Belfast, Northern Ireland, United Kingdom BT9 5AG
| | - Stefan Mix
- Department
of Biocatalysis, Almac Bioscience, Almac
Group, Almac House, 20 Seagoe Industrial Estate, Craigavon, Belfast, Northern Ireland, United Kingdom BT63 5QD
| | - Patricia C. Marr
- School
of Chemistry and Chemical Engineering, Queen’s
University Belfast, UK, David Keir Building, Stranmillis Road, Belfast, Northern Ireland, United Kingdom BT9 5AG
- E-mail:
| | - Andrew C. Marr
- School
of Chemistry and Chemical Engineering, Queen’s
University Belfast, UK, David Keir Building, Stranmillis Road, Belfast, Northern Ireland, United Kingdom BT9 5AG
- E-mail:
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3
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Alacid Y, Martínez-Tomé MJ, Esquembre R, Herrero MA, Mateo CR. Portable Alkaline Phosphatase-Hydrogel Platform: From Enzyme Characterization to Phosphate Sensing. Int J Mol Sci 2023; 24:2672. [PMID: 36769007 PMCID: PMC9917215 DOI: 10.3390/ijms24032672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/23/2023] [Accepted: 01/27/2023] [Indexed: 02/04/2023] Open
Abstract
Here, we present a study on the incorporation and characterization of the enzyme alkaline phosphatase (ALP) into a three-dimensional polymeric network through a green protocol to obtain transparent hydrogels (ALP@AETA) that can be stored at room temperature and potentially used as a disposable biosensor platform for the rapid detection of ALP inhibitors. For this purpose, different strategies for the immobilization of ALP in the hydrogel were examined and the properties of the new material, compared to the hydrogel in the absence of enzyme, were studied. The conformation and stability of the immobilized enzyme were characterized by monitoring the changes in its intrinsic fluorescence as a function of temperature, in order to study the unfolding/folding process inside the hydrogel, inherently related to the enzyme activity. The results show that the immobilized enzyme retains its activity, slightly increases its thermal stability and can be stored as a xerogel at room temperature without losing its properties. A small portion of a few millimeters of ALP@AETA xerogel was sufficient to perform enzymatic activity inhibition assays, so as a proof of concept, the device was tested as a portable optical biosensor for the detection of phosphate in water with satisfactory results. Given the good stability of the ALP@AETA xerogel and the interesting applications of ALP, not only in the environmental field but also as a therapeutic enzyme, we believe that this study could be of great use for the development of new devices for sensing and protein delivery.
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Affiliation(s)
- Yolanda Alacid
- Instituto de Investigación, Desarrollo e Innovación en Biotecnología Sanitaria de Elche (IDiBE), Universidad Miguel Hernández de Elche (UMH), 03202 Elche, Spain
| | - María José Martínez-Tomé
- Instituto de Investigación, Desarrollo e Innovación en Biotecnología Sanitaria de Elche (IDiBE), Universidad Miguel Hernández de Elche (UMH), 03202 Elche, Spain
| | - Rocío Esquembre
- Instituto de Investigación, Desarrollo e Innovación en Biotecnología Sanitaria de Elche (IDiBE), Universidad Miguel Hernández de Elche (UMH), 03202 Elche, Spain
| | - M. Antonia Herrero
- Instituto Regional de Investigación Científica Aplicada (IRICA), Universidad de Castilla-La Mancha, Avda. Camilo José Cela, s/n, 13071 Ciudad Real, Spain
| | - C. Reyes Mateo
- Instituto de Investigación, Desarrollo e Innovación en Biotecnología Sanitaria de Elche (IDiBE), Universidad Miguel Hernández de Elche (UMH), 03202 Elche, Spain
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4
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Glucose oxidase converted into a general sugar-oxidase. Sci Rep 2022; 12:10716. [PMID: 35739181 PMCID: PMC9226012 DOI: 10.1038/s41598-022-14957-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 06/15/2022] [Indexed: 11/09/2022] Open
Abstract
Entrapment of glucose oxidase (GOx) within metallic gold converts this widely used enzyme into a general saccharide oxidase. The following sugar molecules were oxidized by the entrapped enzyme (in addition to D-glucose): fructose, xylose, L-glucose, glucose-6-phosphate, sucrose, lactose, methylglucoside, and the tri-saccharide raffinose. With the exception of raffinose, none of these sugars have a natural specific oxidase. The origin of this generalization of activity is attributed to the strong protein-gold 3D interactions and to the strong interactions of the co-entrapped CTAB with both the gold, and the protein. It is proposed that these interactions induce conformational changes in the channel leading to the active site, which is located at the interface between the two units of the dimeric GOx protein. The observations are compatible with affecting the specific conformation change of pulling apart and opening this gate-keeper, rendering the active site accessible to a variety of substrates. The entrapment methodology was also found to increase the thermal stability of GOx up to 100 °C and to allow its convenient reuse, two features of practical importance.
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5
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Zhao YT, Zhang K, Zeng J, Yin H, Zheng W, Li R, Ding A, Chen S, Liu Y, Wu W, Jing Z. Immobilization on magnetic PVA/SA@Fe3O4 hydrogel beads enhances the activity and stability of neutral protease. Enzyme Microb Technol 2022; 157:110017. [DOI: 10.1016/j.enzmictec.2022.110017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 02/07/2022] [Accepted: 02/09/2022] [Indexed: 11/03/2022]
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6
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Yang P, Chen H, Zhu Q, Chen Z, Yang Z, Yuan R, Li Y, Liang W. A target-initiated autocatalytic 3D DNA nanomachine for high-efficiency amplified detection of MicroRNA. Talanta 2022; 240:123219. [PMID: 35026639 DOI: 10.1016/j.talanta.2022.123219] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 01/04/2022] [Accepted: 01/07/2022] [Indexed: 11/18/2022]
Abstract
Considering the challenges of generating simple and efficient DNA (deoxyribonucleic acid) nanomachines for sensitive bioassays and the great potential of target-induced self-cycling catalytic systems, herein, a novel autocatalytic three-dimensional (3D) DNA nanomachine was constructed based on cross-catalytic hairpin assembly on gold nanoparticles (AuNPs) to generate self-powered efficient cyclic amplification. Typically, the DNA hairpins H1, H2, H3 and H4 were immobilized onto AuNPs first. In the presence of target microRNA-203a, the 3D DNA nanomachines were triggered to activate a series of CHA (catalytic hairpin assembly) reactions. Based on the rational design of the system, the products of the CHA 1 reaction were the trigger of the CHA 2 reaction, which could trigger the CHA 1 reaction in turn, generating an efficient self-powered CHA amplification strategy without adding fuel DNA strands or protein enzymes externally and producing high-efficiency fluorescence signal amplification. More importantly, the proposed autocatalytic 3D DNA nanomachines outperformed conventional 3D DNA nanomachines combined with the single-directional cyclic amplification strategy to maximize the amplification efficiency. This strategy not only achieves high-efficiency analysis of microRNAs (microribonucleic acids) in vitro and intracellularly but also provides a new pathway for highly processive DNA nanomachines, offering a new avenue for bioanalysis and early clinical diagnosis.
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Affiliation(s)
- Peng Yang
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, PR China
| | - Haoran Chen
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, PR China
| | - Quanjing Zhu
- Department of Clinical and Military Laboratory Medicine, College of Medical Laboratory Science, Army Medical University, Chongqing, 400038, PR China
| | - Zhaopeng Chen
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, PR China
| | - Zezhou Yang
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, PR China
| | - Ruo Yuan
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, PR China
| | - Yan Li
- Department of Clinical and Military Laboratory Medicine, College of Medical Laboratory Science, Army Medical University, Chongqing, 400038, PR China.
| | - Wenbin Liang
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, PR China.
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yang Y, Mao G, Ji X, He ZK. Synthesis of bio-templated clickable quantum dots and dual-emitting organic/inorganic complex for ratiometric fluorescence visual assay of blood glucose. J Mater Chem B 2022; 10:4473-4478. [DOI: 10.1039/d2tb00435f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
With the prevalence of diabetes, rapid and simple blood glucose monitoring becomes more and more important. Here, we reported the synthesis of the bio-templated N3-CdZnTeS quantum dots (QDs), which was...
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8
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Guan L, Wu F, Ren G, Wang J, Yang X, Huang X, Yu P, Lin Y, Mao L. Role of rare-earth elements in enhancing bioelectrocatalysis for biosensing with NAD +-dependent glutamate dehydrogenase. Chem Sci 2021; 12:13434-13441. [PMID: 34777762 PMCID: PMC8528072 DOI: 10.1039/d1sc00193k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 09/01/2021] [Indexed: 11/21/2022] Open
Abstract
Dehydrogenases (DHs) are widely explored bioelectrocatalysts in the development of enzymatic bioelectronics like biosensors and biofuel cells. However, the relatively low intrinsic reaction rates of DHs which mostly depend on diffusional coenzymes (e.g., NAD+) have limited their bioelectrocatalytic performance in applications such as biosensors with a high sensitivity. In this study, we find that rare-earth elements (REEs) can enhance the activity of NAD+-dependent glutamate dehydrogenase (GDH) toward highly sensitive electrochemical biosensing of glutamate in vivo. Electrochemical studies show that the sensitivity of the GDH-based glutamate biosensor is remarkably enhanced in the presence of REE cations (i.e., Yb3+, La3+ or Eu3+) in solution, of which Yb3+ yields the highest sensitivity increase (ca. 95%). With the potential effect of REE cations on NAD+ electrochemistry being ruled out, homogeneous kinetic assays by steady-state and stopped-flow spectroscopy reveal a two-fold enhancement in the intrinsic reaction rate of GDH by introducing Yb3+, mainly through accelerating the rate-determining NADH releasing step during the catalytic cycle. In-depth structural investigations using small angle X-ray scattering and infrared spectroscopy indicate that Yb3+ induces the backbone compaction of GDH and subtle β-sheet transitions in the active site, which may reduce the energetic barrier to NADH dissociation from the binding pocket as further suggested by molecular dynamics simulation. This study not only unmasks the mechanism of REE-promoted GDH kinetics but also paves a new way to highly sensitive biosensing of glutamate in vivo.
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Affiliation(s)
- Lihao Guan
- Department of Chemistry, Capital Normal University Beijing 100048 China
| | - Fei Wu
- Beijing National Laboratory for Molecular Science, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, University of Chinese Academy of Sciences Beijing 100049 China
| | - Guoyuan Ren
- Department of Chemistry, Capital Normal University Beijing 100048 China
| | - Jialu Wang
- Department of Chemistry, Capital Normal University Beijing 100048 China
| | - Xiaoti Yang
- Beijing National Laboratory for Molecular Science, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, University of Chinese Academy of Sciences Beijing 100049 China
| | - Xiaohua Huang
- National and Local Joint Engineering Research Center of Biomedical Functional Materials, Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University Nanjing 210023 China
| | - Ping Yu
- Beijing National Laboratory for Molecular Science, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, University of Chinese Academy of Sciences Beijing 100049 China
| | - Yuqing Lin
- Department of Chemistry, Capital Normal University Beijing 100048 China
| | - Lanqun Mao
- Beijing National Laboratory for Molecular Science, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, University of Chinese Academy of Sciences Beijing 100049 China
- College of Chemistry, Beijing Normal University Beijing 100875 China
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9
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Sun M, Peng S, Nie L, Zou Y, Yang L, Gao L, Dou X, Zhao C, Feng C. Three-Dimensional Chiral Supramolecular Microenvironment Strategy for Enhanced Biocatalysis. ACS NANO 2021; 15:14972-14984. [PMID: 34491712 DOI: 10.1021/acsnano.1c05212] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
How the three-dimensional (3D) chiral environment affects the biocatalysis remains an important issue, thereby inspiring the development of a microenvironment that highly mimics the natural features of enzyme to guarantee enhanced biocatalysis. In this study, two gelators bearing d/l-phenylalanine as chiral centers are designed to construct the 3D chiral catalytic microenvironment for enhancing the biocatalysis of lipase. Such a microenvironment is programmed through chiral transmission of chirality from molecular chirality to achiral polymers. It shows that the chirality of the microenvironment evidently influences the catalytic efficiency of immobilized lipase inside the system, and the 3D microenvironment constructed by right-handed helical nanostructures can enhance the catalytic activity of lipase inside as high as 10-fold for catalyzing 4-nitrophenyl palmitate (NPP) to 4-nitrophenol (NP) and 1.4-fold for catalyzing lipids to triglycerides (TGs) in 3T3-L1 cells than that of the achiral microenvironment. Moreover, the 3D chiral microenvironment has the merits of good catalytic efficiency, high storage stability, and efficient recyclability. This strategy of designing a 3D chiral microenvironment suitable for biocatalysis will overcome the present limitations of enzymatic immobilization in traditional materials and enhance the understanding of biocatalysis.
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Affiliation(s)
- Meng Sun
- State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
- College of Life Science, Xinyang Normal University, Xinyang 464000, China
| | - Shiqiao Peng
- Shanghai Diabetes Institute, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China
| | - Lei Nie
- College of Life Science, Xinyang Normal University, Xinyang 464000, China
| | - Yunqing Zou
- State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Li Yang
- State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Laiben Gao
- State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xiaoqiu Dou
- State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Changli Zhao
- State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Chuanliang Feng
- State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
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Meena J, Gupta A, Ahuja R, Singh M, Panda AK. Recent advances in nano-engineered approaches used for enzyme immobilization with enhanced activity. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.116602] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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11
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Baruch-Shpigler Y, Avnir D. Entrapment of glucose oxidase within gold converts it to a general monosaccharide-oxidase. Sci Rep 2021; 11:10737. [PMID: 34031493 PMCID: PMC8144553 DOI: 10.1038/s41598-021-90242-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 04/23/2021] [Indexed: 12/14/2022] Open
Abstract
We report that entrapping glucose oxidase (GOx) within metallic gold, expands its activity to become an oxidase for monosaccharides that do not have a natural enzyme with that activity-fructose and xylose-and that this entrapment also removes the enantioselectivity, rendering this enzyme capable of oxidizing the "wrong" L-enantiomer of glucose. These observations suggest that in this biomaterial adsorptive interactions of the outer regions of the protein with the gold cage, pull apart and widen the tunnel between the two monomeric units of GOx, to a degree that its stereoselectivity is compromised; then, the active sites which are more versatile than currently attributed to, are free and capable of acting on the foreign sugars. To test this proposition, we entrapped in gold L-asparaginase, which is also a dimeric enzyme (a dimer of tight dimers), and found, again, that this metallic biomaterial widens the activity of that enzyme, to include the D-amino acid counter enantiomer as well. Detailed kinetic analyses for all substrates are provided for the gold bio-composites, including determination of the difference between the activation energies towards two opposite enantiomers.
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Affiliation(s)
- Yael Baruch-Shpigler
- Institute of Chemistry and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, 9190401, Jerusalem, Israel
| | - David Avnir
- Institute of Chemistry and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, 9190401, Jerusalem, Israel.
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Abstract
Bioelectrocatalysis using redox enzymes appears as a sustainable way for biosensing, electricity production, or biosynthesis of fine products. Despite advances in the knowledge of parameters that drive the efficiency of enzymatic electrocatalysis, the weak stability of bioelectrodes prevents large scale development of bioelectrocatalysis. In this review, starting from the understanding of the parameters that drive protein instability, we will discuss the main strategies available to improve all enzyme stability, including use of chemicals, protein engineering and immobilization. Considering in a second step the additional requirements for use of redox enzymes, we will evaluate how far these general strategies can be applied to bioelectrocatalysis.
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