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Bader LPE, Klok HA. Chemical Approaches for the Preparation of Bacteria - Nano/Microparticle Hybrid Systems. Macromol Biosci 2023; 23:e2200440. [PMID: 36454518 DOI: 10.1002/mabi.202200440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 11/24/2022] [Indexed: 12/05/2022]
Abstract
Bacteria represent a class of living cells that are very attractive carriers for the transport and delivery of nano- and microsized particles. The use of cell-based carriers, such as for example bacteria, may allow to precisely direct nano- or microsized cargo to a desired site, which would greatly enhance the selectivity of drug delivery and allow to mitigate side effects. One key step towards the use of such nano-/microparticle - bacteria hybrids is the immobilization of the cargo on the bacterial cell surface. To fabricate bacteria - nano-/microparticle biohybrid microsystems, a wide range of chemical approaches are available that can be used to immobilize the particle payload on the bacterial cell surface. This article presents an overview of the various covalent and noncovalent chemistries that are available for the preparation of bacteria - nano-/microparticle hybrids. For each of the different chemical approaches, an overview will be presented that lists the bacterial strains that have been modified, the type and size of nanoparticles that have been immobilized, as well as the methods that have been used to characterize the nanoparticle-modified bacteria.
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Affiliation(s)
- Lisa Patricia Elisabeth Bader
- École Polytechnique Fédérale de Lausanne (EPFL), Institut des Matériaux and Institut des Sciences et Ingénierie Chimiques, Laboratoire des Polymères, Bâtiment MXD, Station 12, Lausanne, CH-1015, Switzerland
| | - Harm-Anton Klok
- École Polytechnique Fédérale de Lausanne (EPFL), Institut des Matériaux and Institut des Sciences et Ingénierie Chimiques, Laboratoire des Polymères, Bâtiment MXD, Station 12, Lausanne, CH-1015, Switzerland
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Characterization and Antibacterial Evaluation of Biodegradable Mannose-Conjugated Fe-MIL-88NH2 Composites Containing Vancomycin against Methicillin-Resistant Staphylococcus aureus Strains. Polymers (Basel) 2022; 14:polym14132712. [PMID: 35808757 PMCID: PMC9269330 DOI: 10.3390/polym14132712] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 06/23/2022] [Accepted: 06/28/2022] [Indexed: 02/07/2023] Open
Abstract
The emergence of bacterial resistance has increased the economic burden of infectious diseases dramatically during the previous few decades. Multidrug resistance (MDR) is difficult to cure in both Gram-negative and positive bacteria and is often incurable with traditional and broad-range antibiotics. Therefore, developing techniques to increase the antibacterial activity of therapeutic drugs is essential. Metal-organic frameworks (MOFs) are extremely versatile hybrid materials made of metal ions coupled via organic bridging ligands. They have been widely used as an excellent vehicle for drug delivery due to their low toxicity, biodegradability, and structural stability upon loading and functionalization. The present study focused on the synthesis of mannose (MNS)-coated MOFs with enhanced surface contact with S. aureus cells. The MNS coating on the surface of MOFs enhances their adherence to bacteria by binding to lectins present on the bacterial cell, resulting in improved VCM cellular penetration and activity against resistant bacteria. Various techniques, including atomic force microscopy, DLS, TGA, FT-IR, and DSC, were employed to analyze MNS-coated MOFs. They were also evaluated for their efficacy against resistant S. aureus. The results indicated that when VCM was loaded into MNS-coated MOFs, their bactericidal activity rose dramatically, resulting in the greater suppression of resistant S. aureus. AFM investigation of S. aureus strains demonstrated total morphological distortion after treatment with MNS-coated drug-loaded MOFs. The results of this work suggest that MNS-coated MOFs may be effective for reversing bacterial resistance to VCM and open new pathways for improving antibiotic therapy for diseases associated with MDR.
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Evaluation of M xO y/fucoidan hybrid system and their application in lipase immobilization process. Sci Rep 2022; 12:7218. [PMID: 35508694 PMCID: PMC9068721 DOI: 10.1038/s41598-022-11319-0] [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: 02/21/2022] [Accepted: 04/21/2022] [Indexed: 11/17/2022] Open
Abstract
In this work, new MxOy/fucoidan hybrid systems were fabricated and applied in lipase immobilization. Magnesium (MgO) and zirconium (ZrO2) oxides were used as MxOy inorganic matrices. In the first step, the proposed oxides were functionalized with fucoidan from Fucus vesiculosus (Fuc). The obtained MgO/Fuc and ZrO2/Fuc hybrids were characterized by means of spectroscopic analyses, including Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and nuclear magnetic resonance. Additionally, thermogravimetric analysis was performed to determine the thermal stability of the hybrids. Based on the results, the mechanism of interaction between the oxide supports and fucoidan was also determined. Furthermore, the fabricated MxOy/fucoidan hybrid materials were used as supports for the immobilization of lipase from Aspergillus niger, and a model reaction (transformation of p-nitrophenyl palmitate to p-nitrophenol) was performed to determine the catalytic activity of the proposed biocatalytic system. In that reaction, the immobilized lipase exhibited high apparent and specific activity (145.5 U/gcatalyst and 1.58 U/mgenzyme for lipase immobilized on MgO/Fuc; 144.0 U/gcatalyst and 2.03 U/mgenzyme for lipase immobilized on ZrO2/Fuc). The immobilization efficiency was also confirmed using spectroscopic analyses (FTIR and XPS) and confocal microscopy.
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Haseena, Khan A, Ghaffar I, Baty RS, Abdel-Daim MM, Habib SM, Kanwal T, Shah MR. Synthesis of Ribose-Coated Copper-Based Metal-Organic Framework for Enhanced Antibacterial Potential of Chloramphenicol against Multi-Drug Resistant Bacteria. Antibiotics (Basel) 2021; 10:1469. [PMID: 34943681 PMCID: PMC8698127 DOI: 10.3390/antibiotics10121469] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/28/2021] [Accepted: 11/11/2021] [Indexed: 01/21/2023] Open
Abstract
The rise in bacterial resistance to currently used antibiotics is the main focus of medical researchers. Bacterial multidrug resistance (MDR) is a major threat to humans, as it is linked to greater rates of chronic disease and mortality. Hence, there is an urgent need for developing effective strategies to overcome the bacterial MDR. Metal-organic frameworks (MOFs) are a new class of porous crystalline materials made up of metal ions and organic ligands that can vary their pore size and structure to better encapsulate drug candidates. This study reports the synthesis of ribose-coated Cu-MOFs for enhanced bactericidal activity of chloramphenicol (CHL) against Escherichia coli (resistant and sensitive) and MDR Pseudomonas aeruginosa. The synthesized Cu-MOFs were characterized with DLS, FT-IR, powder X-ray diffraction, scanning electron microscope, and atomic force microscope. They were further investigated for their efficacy against selected bacterial strains. The synthesized ribose-coated Cu-MOFs were observed as spherical shape structure with the particle size of 562.84 ± 13.42 nm. CHL caused the increased inhibition of E. coli and MDR P. aeruginosa with significantly reduced MIC and MBIC values after being encapsulated in ribose-coated Cu-MOFs. The morphological analysis of the bacterial strains treated with ribose-coated CHL-Cu-MOFs showed the complete morphological distortion of both E. coli and MDR P. aeruginosa. Based on the results of the study, it can be suggested that ribose-coated Cu-MOFs may be an effective alternate candidate to overcome the MDR and provide new perspective for the treatment of MDR bacterial infections.
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Affiliation(s)
- Haseena
- Institute of Chemical Sciences, University of Peshawar, Peshawar 25120, Pakistan; (H.); (A.K.)
| | - Adnan Khan
- Institute of Chemical Sciences, University of Peshawar, Peshawar 25120, Pakistan; (H.); (A.K.)
| | - Iqra Ghaffar
- International Centre for Chemical and Biological Sciences, Research Institute of Chemistry, University of Karachi, Karachi 74200, Pakistan; (I.G.); (S.M.H.); (T.K.)
| | - Roua S. Baty
- Department of Biotechnology, College of Science, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia;
| | - Mohamed M. Abdel-Daim
- Pharmacology Department, Faculty of Veterinary Medicine, Suez Canal University, Ismailia 41522, Egypt;
| | - Shahida M. Habib
- International Centre for Chemical and Biological Sciences, Research Institute of Chemistry, University of Karachi, Karachi 74200, Pakistan; (I.G.); (S.M.H.); (T.K.)
| | - Tasmina Kanwal
- International Centre for Chemical and Biological Sciences, Research Institute of Chemistry, University of Karachi, Karachi 74200, Pakistan; (I.G.); (S.M.H.); (T.K.)
| | - Muhammad Raza Shah
- International Centre for Chemical and Biological Sciences, Research Institute of Chemistry, University of Karachi, Karachi 74200, Pakistan; (I.G.); (S.M.H.); (T.K.)
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Cui Z, Wang Z, Zheng M, Chen T. Advances in biological production of acetoin: a comprehensive overview. Crit Rev Biotechnol 2021; 42:1135-1156. [PMID: 34806505 DOI: 10.1080/07388551.2021.1995319] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Acetoin, a high-value-added bio-based platform chemical, is widely used in foods, cosmetics, agriculture, and the chemical industry. It is an important precursor for the synthesis of: 2,3-butanediol, liquid hydrocarbon fuels and heterocyclic compounds. Since the fossil resources are becoming increasingly scarce, biological production of acetoin has received increasing attention as an alternative to chemical synthesis. Although there are excellent reviews on the: application, catabolism and fermentative production of acetoin, little attention has been paid to acetoin production via: electrode-assisted fermentation, whole-cell biocatalysis, and in vitro/cell-free biocatalysis. In this review, acetoin biosynthesis pathways and relevant key enzymes are firstly reviewed. In addition, various strategies for biological acetoin production are summarized including: cell-free biocatalysis, whole-cell biocatalysis, microbial fermentation, and electrode-assisted fermentation. The advantages and disadvantages of the different approaches are discussed and weighed, illustrating the increasing progress toward economical, green and efficient production of acetoin. Additionally, recent advances in acetoin extraction and recovery in downstream processing are also briefly reviewed. Moreover, the current issues and future prospects of diverse strategies for biological acetoin production are discussed, with the hope of realizing the promises of industrial acetoin biomanufacturing in the near future.
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Affiliation(s)
- Zhenzhen Cui
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, China
| | - Zhiwen Wang
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, China
| | - Meiyu Zheng
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, China
| | - Tao Chen
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, China
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Fan XM, Shen JJ, Xu YY, Gao J, Zhang YW. Metabolic integration of azide functionalized glycan on Escherichia coli cell surface for specific covalent immobilization onto magnetic nanoparticles with click chemistry. BIORESOURCE TECHNOLOGY 2021; 324:124689. [PMID: 33450627 DOI: 10.1016/j.biortech.2021.124689] [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] [Received: 11/28/2020] [Revised: 01/04/2021] [Accepted: 01/05/2021] [Indexed: 06/12/2023]
Abstract
A method for specific immobilization of whole-cell with covalent bonds was developed through a click reaction between alkyne and azide groups. In this approach, magnetic nanoparticle Fe3O4@SiO2-NH2-alkyne was synthesized with Fe3O4 core preparation, SiO2 coating, and alkyne functionalization on the surface. The azides were successfully integrated onto the cell surface of the recombinant E. coli harboring glycerol dehydrogenase, which was employed as the model cell. The highest immobilization yield of 83% and activity recovery of 94% were obtained under the conditions of 0.67 mg mg-1 cell-support ratio, pH 6.0, temperature 45 °C, and 20 mM Cu2+ concentration. The immobilized cell showed good reusability, which remained over 50% of initial activity after 10 cycles of utilization. Its activity was 9.7-fold higher than that of the free cell at the condition of pH 8.0 and each optimal temperature. Furthermore, the immobilized cell showed significantly higher activity, operational stability, and reusability.
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Affiliation(s)
- Xiao-Man Fan
- School of Pharmacy, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Jia-Jia Shen
- School of Pharmacy, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Yuan-Yuan Xu
- School of Pharmacy, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Jian Gao
- College of Petroleum and Chemical Engineering, Beibu Gulf University, 535100 Qinzhou, People's Republic of China
| | - Ye-Wang Zhang
- School of Pharmacy, Jiangsu University, Zhenjiang 212013, People's Republic of China; College of Petroleum and Chemical Engineering, Beibu Gulf University, 535100 Qinzhou, People's Republic of China.
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Su WB, Li FL, Li XY, Fan XM, Liu RJ, Zhang YW. Using galactitol dehydrogenase coupled with water-forming NADH oxidase for efficient enzymatic synthesis of L-tagatose. N Biotechnol 2021; 62:18-25. [PMID: 33460816 DOI: 10.1016/j.nbt.2021.01.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 01/05/2021] [Accepted: 01/11/2021] [Indexed: 10/22/2022]
Abstract
L-Tagatose, a promising building block in the production of many value-added chemicals, is generally produced by chemical routes with a low yield, which may not meet the increasing demands. Synthesis of l-tagatose by enzymatic oxidation of d-galactitol has not been applied on an industrial scale because of the high cofactor costs and the lack of efficient cofactor regeneration methods. In this work, an efficient and environmentally friendly enzymatic method containing a galactitol dehydrogenase for d-galactitol oxidation and a water-forming NADH oxidase for regeneration of NAD+ was first designed and used for l-tagatose production. Supplied with only 3 mM NAD+, subsequent reaction optimization facilitated the efficient transformation of 100 mM of d-galactitol into l-tagatose with a yield of 90.2 % after 12 h (obtained productivity: 7.61 mM.h-1). Compared with the current chemical and biocatalytic methods, the strategy developed avoids by-product formation and achieves the highest yield of l-tagatose with low costs. It is expected to become a cleaner and more promising route for industrial biosynthesis of l-tagatose.
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Affiliation(s)
- Wen-Bin Su
- School of Pharmacy, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Fei-Long Li
- School of Pharmacy, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Xue-Yong Li
- School of Pharmacy, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Xiao-Man Fan
- School of Pharmacy, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Rui-Jiang Liu
- School of Pharmacy, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Ye-Wang Zhang
- School of Pharmacy, Jiangsu University, Zhenjiang, 212013, People's Republic of China; College of Petroleum and Chemical Engineering, Beibu Gulf University, Qinzhou, 535011, People's Republic of China.
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Sheng X, Wang B, Mao C, Sha X, Zhou Y. Influence of FeCl
3
‐modified chloroaluminate ionic liquids on long‐chain alkenes alkylation. Appl Organomet Chem 2021. [DOI: 10.1002/aoc.6055] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Xiaoli Sheng
- School of Chemistry and Chemical Engineering, Jiangsu Optoelectronic Functional Materials and Engineering Laboratory Southeast University Nanjing 211189 China
| | - Beibei Wang
- School of Chemistry and Chemical Engineering, Jiangsu Optoelectronic Functional Materials and Engineering Laboratory Southeast University Nanjing 211189 China
| | - Chunfeng Mao
- School of Chemistry and Chemical Engineering, Jiangsu Optoelectronic Functional Materials and Engineering Laboratory Southeast University Nanjing 211189 China
| | - Xiao Sha
- School of Chemistry and Chemical Engineering, Jiangsu Optoelectronic Functional Materials and Engineering Laboratory Southeast University Nanjing 211189 China
| | - Yuming Zhou
- School of Chemistry and Chemical Engineering, Jiangsu Optoelectronic Functional Materials and Engineering Laboratory Southeast University Nanjing 211189 China
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Expression, biochemical characterization, and mutation of a water forming NADH: FMN oxidoreductase from Lactobacillus rhamnosus. Enzyme Microb Technol 2019; 134:109464. [PMID: 32044036 DOI: 10.1016/j.enzmictec.2019.109464] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 10/29/2019] [Accepted: 11/02/2019] [Indexed: 01/03/2023]
Abstract
Enzyme-catalyzed cofactor regeneration is a significant approach to avoid large quantities consumption of oxidized cofactor, which is vital in a variety of bioconversion reactions. NADH: FMN oxidoreductase is an ideal regenerating enzyme because innocuous molecular oxygen is required as an oxidant. But the by-product H2O2 limits its further applications at the industrial scale. Here, novel NADH: FMN oxidoreductase (LrFOR) from Lactobacillus rhamnosus comprised of 1146 bp with a predicted molecular weight of 42 kDa was cloned and overexpressed in Escherichia coli BL21 (DE3). Enzyme assay shows that the purified recombinant LrFOR has both the NADPH and NADH oxidation activity. Biochemical characterizations suggested that LrFOR exhibits the specific activity of 39.8 U·mg-1 with the optimal pH and temperature of 5.6 and 35 °C and produces H2O instead of potentially harmful peroxide. To further study its catalytic function, a critical Thr29 residue and its six mutants were investigated. Mutants T29G, T29A, and T29D show notable enhancement in activities compared with the wild type. Molecular docking of NADH into wild type and its mutants reveal that a small size or electronegative of residue in position29 could shorten the distance of NADH and FMN, promoting the electrons transfer and resulting in the increased activity. This work reveals the pivotal role of position 29 in the catalytic function of LrFOR and provides effective catalysts in NAD+ regeneration.
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Xu MQ, Li FL, Yu WQ, Li RF, Zhang YW. Combined cross-linked enzyme aggregates of glycerol dehydrogenase and NADH oxidase for high efficiency in situ NAD + regeneration. Int J Biol Macromol 2019; 144:1013-1021. [PMID: 31669469 DOI: 10.1016/j.ijbiomac.2019.09.178] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 09/10/2019] [Accepted: 09/21/2019] [Indexed: 02/06/2023]
Abstract
Cofactor regeneration is an important method to avoid the consumption of large quantities of oxidized cofactor NAD+ in enzyme-catalyzed reactions. Herein, glycerol dehydrogenase (GDH) and NADH oxidase preparations by aggregating enzymes with ammonium sulphate followed by cross-linking formed aggregates for effective regeneration of NAD+. After optimization, the activity of combi-CLEAs and separate CLEAs mixtures were 950 and 580 U/g, respectively. And the catalytic stability of combi-CLEAs against pH and temperature was superior to the free enzyme mixture. After ten cycles of reuse, the catalytic efficiency could still retain 63.3% of its initial activity, indicating that the constructed combi-CLEAs system had excellent reusability. Also, the conversion of glycerol to 1,3-dihydroxyacetone (DHA) was improved by the constructed NAD+ regeneration system, resulting in 4.6%, which was 2.5 times of the free enzyme system. Thus, wide applications of this co-immobilization method in the production of various chiral chemicals could be expected in the industry for its high efficiency at a low cost.
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Affiliation(s)
- Meng-Qiu Xu
- School of Pharmacy, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Fei-Long Li
- School of Pharmacy, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Wen-Qian Yu
- School of Pharmacy, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Rui-Fang Li
- School of Pharmacy, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Ye-Wang Zhang
- School of Pharmacy, Jiangsu University, Zhenjiang 212013, People's Republic of China.
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Abstract
The use of biocatalysts, including enzymes and metabolically engineered cells, has attracted a great deal of attention in chemical and bio-industry, because biocatalytic reactions can be conducted under environmentally-benign conditions and in more sustainable ways [...]
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Correction: Li, F.-L. et al. Specific Immobilization of Escherichia coli Expressing Recombinant Glycerol Dehydrogenase on Mannose-Functionalized Magnetic Nanoparticles. Catalysts 2019, 9, 7. Catalysts 2019. [DOI: 10.3390/catal9070585] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The authors wish to make the following corrections to our published paper [...]
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Role of introduced surface cysteine of NADH oxidase from Lactobacillus rhamnosus. Int J Biol Macromol 2019; 132:150-156. [DOI: 10.1016/j.ijbiomac.2019.03.168] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 03/10/2019] [Accepted: 03/25/2019] [Indexed: 12/15/2022]
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Switching the substrate specificity from NADH to NADPH by a single mutation of NADH oxidase from Lactobacillus rhamnosus. Int J Biol Macromol 2019; 135:328-336. [PMID: 31128193 DOI: 10.1016/j.ijbiomac.2019.05.146] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 05/14/2019] [Accepted: 05/14/2019] [Indexed: 02/07/2023]
Abstract
Enzymatic NADP+ regeneration is a promising approach to produce valuable chemicals under economic conditions. Among all the enzymatic routes, using water-forming NADH oxidase is an ideal one because there is no by-product. However, most NADH oxidases have a low specific activity to NADPH. In this work, a thermostable NADH oxidase from Lactobacillus rhamnosus (LrNox) was rationally engineered to switch its specificity from NADH to NADPH. The results show that mutants D177A, G178R, D177A/G178R, D177A/G178R/L179S improved the NADPH activity by a factor of 4-6. The highest NADPH catalytic efficiency (Kcat/Km 223.71 S-1 μm-1, 47.6-fold higher than wild-type LrNox) and 51% of NADH activity retention were achieved by replacing the single amino acid Leu179 for serine (L179S) in LrNox. Modeling of L179S-NADPH complex reveals that the phosphate group of NADPH interacts with the hydroxyl of Ser179 with a strong hydrogen bond and several shorter hydrogen bonds with the amino group of Lys185 could stabilize the binding of NADPH in the L179S mutant. This work provides an efficient method for converting NAD(P)H specificity and shows that L179S mutant is a potential and efficient auxiliary enzyme for NADP+ regeneration.
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Zhao Y, Li T, Meng X, Wang H, Zhang Y, Wang H, Zhang S. Improvement of product distribution through enhanced mass transfer in isobutane/butene alkylation. Chem Eng Res Des 2019. [DOI: 10.1016/j.cherd.2018.12.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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