Co-reporter:Tiezheng Pan, Yao Liu, Chengye Si, Yushi Bai, Shanpeng Qiao, Linlu Zhao, Jiayun Xu, Zeyuan Dong, Quan Luo, and Junqiu Liu
ACS Catalysis March 3, 2017 Volume 7(Issue 3) pp:1875-1875
Publication Date(Web):February 6, 2017
DOI:10.1021/acscatal.6b03274
Rational redesign of allosteric protein offers an efficient strategy to develop switchable biocatalysts. By combining the computational design and protein engineering, a glutathione peroxidase (GPx)-like active center that contains the catalytic selenocysteine (Sec) residue and substrate-binding Arg residue was precisely incorporated into the allosteric domain of adenylate kinase (AKe). The engineered selenoenzyme shows not only high GPx activity but also adenosine triphosphate (ATP)-responsive catalytic property, which is regulated by its opened to closed conformational change upon ATP binding. Theoretical and mutational analysis reveals that the synergistic effect of electrostatic interactions and van der Waals (vdW) interactions for substrate recognition is a major contribution to the high activity. The mitochondrial oxidative damage experiment further demonstrated its antioxidant ability at the subcellular level, offering a potential application toward controllable catalysis in vivo.Keywords: adenylate kinase; allosteric switches; antioxidant; artificial selenoenzyme; enzyme design;
Co-reporter:Lu Miao, Qiusheng Fan, Linlu Zhao, Qinglong Qiao, Xiyu Zhang, Chunxi Hou, Jiayun Xu, Quan Luo and Junqiu Liu
Chemical Communications 2016 vol. 52(Issue 21) pp:4092-4095
Publication Date(Web):15 Feb 2016
DOI:10.1039/C6CC00632A
A simple strategy has been developed to construct high-ordered protein nanotubes using electrostatic interactions and “zero-length” crosslinking induced by small molecular ethylenediamine. Furthermore, utilizing covalent crosslinking, we constructed stable nanoenzymes with multi-glutathione peroxidase (GPx) active centers on the surface of the nanotubes, which were anticipated to be ideal functional bionanomaterials.
Co-reporter:Libo Li, Xia Li, Quan Luo, Tianyan You
Talanta 2015 Volume 142() pp:28-34
Publication Date(Web):1 September 2015
DOI:10.1016/j.talanta.2015.04.039
•Four chiral drugs were enantioseparated basically by CE using CM-β-CD.•ITC, NMR and MM were combined to provide deeper understanding of the processes.•The method may be helpful in choosing suitable chiral selectors.•The method can assist to predict chiral CE results before experiments.Four chiral drugs were enantioseparated by native beta-cyclodextrin (β-CD) and negatively charged carboxymethyl-beta-cyclodextrin (CM-β-CD) using capillary electrophoresis coupled with electrochemiluminescence detection (CE-ECL). Using 50 mM pH 5.5 Tris–H3PO4 with 10 mM CM-β-CD as a running buffer, high resolution efficiency could be obtained. With the help of isothermal titration calorimetry (ITC), nuclear magnetic resonance (NMR) and molecular modeling, the chiral recognition mechanism was comprehensively investigated. Thermodynamic parameters data from ITC revealed that CM-β-CD exhibited stronger binding affinity with analytes than β-CD, and that the driving forces of CM-β-CD responsible for chiral recognition were mainly electrostatic interactions between negatively charged CM-β-CD and positively charged analytes. In addition, from both a macroscopic and microscopic point of view, the results of NMR and molecular modeling investigation adequately confirm the conclusion by comparing the stereochemical structures of complexes. Combination of ITC, NMR and molecular modeling techniques not only can assist CE to investigate the chiral discrimination mechanism, but also can predict and guide CE enantioseparation efficiency conversely.Four chiral drugs were enantioseparated by cyclodextrin-mediated capillary electrophoresis, and higher resolution efficiency was obtained using carboxymethyl -beta-cyclodextrinas chiral selector. Isothermal titrational calorimetry, nuclear magnetic resonance and molecular modeling were combined together to investigate the recognition process.
Co-reporter:Lu Miao, Xiyu Zhang, Chengye Si, Yuzhou Gao, Linlu Zhao, Chunxi Hou, Oded Shoseyov, Quan Luo and Junqiu Liu
Organic & Biomolecular Chemistry 2014 vol. 12(Issue 2) pp:362-369
Publication Date(Web):11 Oct 2013
DOI:10.1039/C3OB41561A
Stable Protein One (SP1) is a boiling-stable oligomeric protein. The unique characteristics of SP1 offer a scaffold to design artificial enzymes against extreme temperature. Here, an efficient antioxidase is successfully constructed on the ring-shaped SP1 homododecamer. By means of computational design and genetic engineering, the active center of glutathione peroxidase (GPx), selenocysteine (Sec), is introduced to the SP1 monomer surface, and the self-assembly properties of the protein monomer lead to a ring-shaped SP1 with homododecamer catalytic selenium centers. This artificial selenoenzyme exhibits high GPx catalytic activity and shows a typical ping-pong kinetic mechanism. Moreover, it has a significantly broader temperature range and high thermostability. Owing to having multi-GPx active centers on a SP1 oligomer, this selenium-containing biomacromolecule exerts an excellent capability to protect cells from oxidative damage at the mitochondrial level. This strategy represents a new way to develop thermostable artificial nanoenzymes for some specific applications.
Co-reporter:Chunqiu Zhang;Tiezheng Pan; Christian Salesse;Dongmei Zhang;Lu Miao;Liang Wang;Yuzhou Gao;Jiayun Xu; Zeyuan Dong; Quan Luo; Junqiu Liu
Angewandte Chemie International Edition 2014 Volume 53( Issue 49) pp:13536-13539
Publication Date(Web):
DOI:10.1002/anie.201407135
Abstract
A Ca2+-responsive artificial selenoenzyme was constructed by computational design and engineering of recoverin with the active center of glutathione peroxidase (GPx). By combining the recognition capacity for the glutathione (GSH) substrate and the steric orientation of the catalytic selenium moiety, the engineered selenium-containing recoverin exhibits high GPx activity for the catalyzed reduction of H2O2 by glutathione (GSH). Moreover, the engineered selenoenzyme can be switched on/off by Ca2+-induced allosterism of the protein recoverin. This artificial selenoenzyme also displays excellent antioxidant ability when it was evaluated using a mitochondrial oxidative damage model, showing great potential for controlled catalysis in biomedical applications.
Co-reporter:Chunqiu Zhang;Tiezheng Pan; Christian Salesse;Dongmei Zhang;Lu Miao;Liang Wang;Yuzhou Gao;Jiayun Xu; Zeyuan Dong; Quan Luo; Junqiu Liu
Angewandte Chemie 2014 Volume 126( Issue 49) pp:13754-13757
Publication Date(Web):
DOI:10.1002/ange.201407135
Abstract
A Ca2+-responsive artificial selenoenzyme was constructed by computational design and engineering of recoverin with the active center of glutathione peroxidase (GPx). By combining the recognition capacity for the glutathione (GSH) substrate and the steric orientation of the catalytic selenium moiety, the engineered selenium-containing recoverin exhibits high GPx activity for the catalyzed reduction of H2O2 by glutathione (GSH). Moreover, the engineered selenoenzyme can be switched on/off by Ca2+-induced allosterism of the protein recoverin. This artificial selenoenzyme also displays excellent antioxidant ability when it was evaluated using a mitochondrial oxidative damage model, showing great potential for controlled catalysis in biomedical applications.
Co-reporter:Zupeng Huang, Shuwen Guan, Yongguo Wang, Guannan Shi, Lina Cao, Yuzhou Gao, Zeyuan Dong, Jiayun Xu, Quan Luo and Junqiu Liu
Journal of Materials Chemistry A 2013 vol. 1(Issue 17) pp:2297-2304
Publication Date(Web):05 Mar 2013
DOI:10.1039/C3TB20156B
Herein, we report the construction of a novel hydrolase model via self-assembly of a synthetic amphiphilic short peptide (Fmoc-FFH-CONH2) into nanotubes. The peptide-based self-assembled nanotubes (PepNTs-His) with imidazolyl groups as the catalytic centers exhibit high catalytic activity for p-nitrophenyl acetate (PNPA) hydrolysis. By replacement of the histidine of Fmoc-FFH-CONH2 with arginine to produce a structurally similar peptide Fmoc-FFR-CONH2, guanidyl groups can be presented in the nanotubes through the co-assembly of these two molecules to stabilize the transition state of the hydrolytic reaction. Therefore significantly improved catalytic activity has been achieved by the reasonable distribution of three dominating catalytic factors: catalytic center, binding site and transition state stabilization to the co-assembled peptide nanotubes (PepNTs-His-Argmax). The resulting hydrolase model shows typical saturation kinetics behaviour to that of natural enzymes and the catalytic efficiency of a single catalytic center is 519-fold higher than that without catalysts. As for a nanotube with multi-catalytic centers, a remarkable catalytic efficiency could be achieved with the increase of building blocks. This model suggests that the well ordered and dynamic supramolecular structure is an attractive platform to develop new artificial enzymes to enhance the catalytic activity. Besides, this novel peptide-based material has excellent biocompatibility with human cells and is expected to be applied to organisms as a substitute for natural hydrolases.
Co-reporter:Yuzhou Gao;Chunxi Hou;Lipeng Zhou;Dongmei Zhang;Chunqiu Zhang;Lu Miao;Liang Wang;Zeyuan Dong;Junqiu Liu
Macromolecular Bioscience 2013 Volume 13( Issue 6) pp:808-816
Publication Date(Web):
DOI:10.1002/mabi.201300019
Co-reporter:Quan Luo;Chunqiu Zhang;Lu Miao;Dongmei Zhang;Yushi Bai;Chunxi Hou
Amino Acids 2013 Volume 44( Issue 3) pp:1009-1019
Publication Date(Web):2013 March
DOI:10.1007/s00726-012-1435-3
By combining computational design and site-directed mutagenesis, we have engineered a new catalytic ability into the antibody scFv2F3 by installing a catalytic triad (Trp29–Sec52–Gln72). The resulting abzyme, Se-scFv2F3, exhibits a high glutathione peroxidase (GPx) activity, approaching the native enzyme activity. Activity assays and a systematic computational study were performed to investigate the effect of successive replacement of residues at positions 29, 52, and 72. The results revealed that an active site Ser52/Sec substitution is critical for the GPx activity of Se-scFv2F3. In addition, Phe29/Trp–Val72/Gln mutations enhance the reaction rate via functional cooperation with Sec52. Molecular dynamics simulations showed that the designed catalytic triad is very stable and the conformational flexibility caused by Tyr101 occurs mainly in the loop of complementarity determining region 3. The docking studies illustrated the importance of this loop that favors the conformational shift of Tyr54, Asn55, and Gly56 to stabilize substrate binding. Molecular dynamics free energy and molecular mechanics-Poisson Boltzmann surface area calculations estimated the pKa shifts of the catalytic residue and the binding free energies of docked complexes, suggesting that dipole–dipole interactions among Trp29–Sec52–Gln72 lead to the change of free energy that promotes the residual catalytic activity and the substrate-binding capacity. The calculated results agree well with the experimental data, which should help to clarify why Se-scFv2F3 exhibits high catalytic efficiency.
Co-reporter:Wei Zhang, Quan Luo, Lu Miao, Chunxi Hou, Yushi Bai, Zeyuan Dong, Jiayun Xu and Junqiu Liu
Nanoscale 2012 vol. 4(Issue 19) pp:5847-5851
Publication Date(Web):30 Jul 2012
DOI:10.1039/C2NR31244A
This study presents the Ni-ion-directed self-assembly of a C2-symmetric homodimeric enzyme into nanowires. A genetically introduced His-tag arm stretches out of the central structure of a C2-symmetric homodimer of glutathione S-transferase, which is used as a linker to recruit a second building block through interprotein metal coordination, forming self-assembled one-dimensional nanostructures with excellent enzymatic activity.
Co-reporter:Yongguo Wang, Lina Cao, Shuwen Guan, Guannan Shi, Quan Luo, Lu Miao, Ian Thistlethwaite, Zupeng Huang, Jiayun Xu and Junqiu Liu
Journal of Materials Chemistry A 2012 vol. 22(Issue 6) pp:2575-2581
Publication Date(Web):21 Dec 2011
DOI:10.1039/C1JM14090F
In this work, we employ Fmoc-peptide-based self-assembled nanofibers which are equipped with numerous carboxylic acid and thiol groups on their exterior as scaffolds for the mineralization of silver nanoparticles (Ag-PepNFs). The space- and size-constraint effect along with physical isolation provided by the nano-templates of peptide nanofibers facilitates the production of Ag nanoparticles (AgNPs) with high monodispersity and stability. These Ag-PepNFs nanocomposites can maintain stability for up to 3 months of storage at room temperature in air. In comparison to the traditional Ag-containing materials, Ag-PepNFs nanocomposites offer obvious advantages of ease of fabrication, good biocompatibility, inexpensive production, functional flexibility. More importantly, the tubular nanocomposite are shown to possess a highly effective and long-term antibacterial activity against both Gram-positive bacteria (Bacillus subtilis) and Gram-negative bacteria (Escherichia coliDH5 α).
Co-reporter:Jiaxi Li;Lipeng Zhou;Yongguo Wang;Chunqiu Zhang;Wei Lu;Jiayun Xu ;Junqiu Liu
Chinese Journal of Chemistry 2012 Volume 30( Issue 9) pp:2085-2090
Publication Date(Web):
DOI:10.1002/cjoc.201200603
Abstract
Cucurbituril (CB), a well-known macrocyclic cavitand, has been used extensively to construct supramolecular aggregates. Based on host-guest intertactions, an adamantanyl derivative guest molecule was designed and synthesized to prepare a supramolecular amphiphile with cucurbit[7]uril. In aqueous solution, the cucurbit[7]uril based supramolecular amphiphiles self-assemble into well-defined vesicles, and their disassembly can be achieved by addition of excess competitive agent 1-adamantanamine hydrochloride. This vesicle functions as a new nanocapsule to encapsulate molecules within its hollow cavity. Through competitive disassembly of supramolecular amphiphiles, the vesicles behave as a novel drug delivery carrier.
Co-reporter:Tiezhu Li;Jinghui Wang;Yuqiu Li;Li Zhang;Li Zheng
Journal of Molecular Modeling 2011 Volume 17( Issue 7) pp:1661-1668
Publication Date(Web):2011 July
DOI:10.1007/s00894-010-0869-3
In the structural-based mutagenesis of Mucor pusillus pepsin (MPP), understanding how κ-casein interacts with MPP is a great challenge for us to explore. Chymosin-sensitive peptide is the key domain of κ-casein that regulates milk clotting through the specific proteolytic cleavage of its peptide bond (Phe105-Met106) by MPP to produce insoluble para-κ-casein. Here, we built the model of this large peptide using molecular modeling technique. Docking study showed that MPP can accommodate the designed model with a favorable binding energy and the docked complex has proven to locally resemble the inhibitor-chymosin complex. The catalytic mechanism for the peptide model binding with MPP was explored in terms of substrate-enzyme interaction and property of contacting surface. Some critical amino acid residues in the substrate binding cleft have been identified as an important guide for further site-directed mutagenesis. Glu13 and Leu11 in the S3 region of MPP, predicted as the special mutation sites, were confirmed to retain clotting activity and decrease the proteolytic activity. These novel mutants may provide a promising application for improving cheese flavor.
Co-reporter:Yongguo Wang, Lina Cao, Shuwen Guan, Guannan Shi, Quan Luo, Lu Miao, Ian Thistlethwaite, Zupeng Huang, Jiayun Xu and Junqiu Liu
Journal of Materials Chemistry A 2012 - vol. 22(Issue 6) pp:NaN2581-2581
Publication Date(Web):2011/12/21
DOI:10.1039/C1JM14090F
In this work, we employ Fmoc-peptide-based self-assembled nanofibers which are equipped with numerous carboxylic acid and thiol groups on their exterior as scaffolds for the mineralization of silver nanoparticles (Ag-PepNFs). The space- and size-constraint effect along with physical isolation provided by the nano-templates of peptide nanofibers facilitates the production of Ag nanoparticles (AgNPs) with high monodispersity and stability. These Ag-PepNFs nanocomposites can maintain stability for up to 3 months of storage at room temperature in air. In comparison to the traditional Ag-containing materials, Ag-PepNFs nanocomposites offer obvious advantages of ease of fabrication, good biocompatibility, inexpensive production, functional flexibility. More importantly, the tubular nanocomposite are shown to possess a highly effective and long-term antibacterial activity against both Gram-positive bacteria (Bacillus subtilis) and Gram-negative bacteria (Escherichia coliDH5 α).
Co-reporter:Zupeng Huang, Shuwen Guan, Yongguo Wang, Guannan Shi, Lina Cao, Yuzhou Gao, Zeyuan Dong, Jiayun Xu, Quan Luo and Junqiu Liu
Journal of Materials Chemistry A 2013 - vol. 1(Issue 17) pp:NaN2304-2304
Publication Date(Web):2013/03/05
DOI:10.1039/C3TB20156B
Herein, we report the construction of a novel hydrolase model via self-assembly of a synthetic amphiphilic short peptide (Fmoc-FFH-CONH2) into nanotubes. The peptide-based self-assembled nanotubes (PepNTs-His) with imidazolyl groups as the catalytic centers exhibit high catalytic activity for p-nitrophenyl acetate (PNPA) hydrolysis. By replacement of the histidine of Fmoc-FFH-CONH2 with arginine to produce a structurally similar peptide Fmoc-FFR-CONH2, guanidyl groups can be presented in the nanotubes through the co-assembly of these two molecules to stabilize the transition state of the hydrolytic reaction. Therefore significantly improved catalytic activity has been achieved by the reasonable distribution of three dominating catalytic factors: catalytic center, binding site and transition state stabilization to the co-assembled peptide nanotubes (PepNTs-His-Argmax). The resulting hydrolase model shows typical saturation kinetics behaviour to that of natural enzymes and the catalytic efficiency of a single catalytic center is 519-fold higher than that without catalysts. As for a nanotube with multi-catalytic centers, a remarkable catalytic efficiency could be achieved with the increase of building blocks. This model suggests that the well ordered and dynamic supramolecular structure is an attractive platform to develop new artificial enzymes to enhance the catalytic activity. Besides, this novel peptide-based material has excellent biocompatibility with human cells and is expected to be applied to organisms as a substitute for natural hydrolases.
Co-reporter:Lu Miao, Xiyu Zhang, Chengye Si, Yuzhou Gao, Linlu Zhao, Chunxi Hou, Oded Shoseyov, Quan Luo and Junqiu Liu
Organic & Biomolecular Chemistry 2014 - vol. 12(Issue 2) pp:NaN369-369
Publication Date(Web):2013/10/11
DOI:10.1039/C3OB41561A
Stable Protein One (SP1) is a boiling-stable oligomeric protein. The unique characteristics of SP1 offer a scaffold to design artificial enzymes against extreme temperature. Here, an efficient antioxidase is successfully constructed on the ring-shaped SP1 homododecamer. By means of computational design and genetic engineering, the active center of glutathione peroxidase (GPx), selenocysteine (Sec), is introduced to the SP1 monomer surface, and the self-assembly properties of the protein monomer lead to a ring-shaped SP1 with homododecamer catalytic selenium centers. This artificial selenoenzyme exhibits high GPx catalytic activity and shows a typical ping-pong kinetic mechanism. Moreover, it has a significantly broader temperature range and high thermostability. Owing to having multi-GPx active centers on a SP1 oligomer, this selenium-containing biomacromolecule exerts an excellent capability to protect cells from oxidative damage at the mitochondrial level. This strategy represents a new way to develop thermostable artificial nanoenzymes for some specific applications.
Co-reporter:Lu Miao, Qiusheng Fan, Linlu Zhao, Qinglong Qiao, Xiyu Zhang, Chunxi Hou, Jiayun Xu, Quan Luo and Junqiu Liu
Chemical Communications 2016 - vol. 52(Issue 21) pp:NaN4095-4095
Publication Date(Web):2016/02/15
DOI:10.1039/C6CC00632A
A simple strategy has been developed to construct high-ordered protein nanotubes using electrostatic interactions and “zero-length” crosslinking induced by small molecular ethylenediamine. Furthermore, utilizing covalent crosslinking, we constructed stable nanoenzymes with multi-glutathione peroxidase (GPx) active centers on the surface of the nanotubes, which were anticipated to be ideal functional bionanomaterials.
![4,7,11,14,18,21-Hexaazatetracosanediamide,N1,N24-bis(2-aminoethyl)-4,21-bis[3-[(2-aminoethyl)amino]-3-oxopropyl]-11,14-bis[3-[[2-[bis[3-[(2-aminoethyl)amino]-3-oxopropyl]amino]ethyl]amino]-3-oxopropyl]-8,17-dioxo-](http://img.cochemist.com/ccimg/143000/142986-44-5.png)
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