1
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Yan M, Chen Y, Feng Y, Saeed M, Fang Z, Zhen W, Ni Z, Chen H. Perspective on Agricultural Industrialization: Modification Strategies for Enhancing the Catalytic Capacity of Keratinase. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024. [PMID: 38832583 DOI: 10.1021/acs.jafc.4c03025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2024]
Abstract
Keratinases is a special hydrolytic enzyme produced by microorganisms, which has the ability to catalyze the degradation of keratin. Currently, keratinases show great potential for application in many agricultural and industrial fields, such as biofermented feed, leather tanning, hair removal, and fertilizer production. However, these potentials have not yet been fully unleashed on an industrial scale. This paper reviews the sources, properties, and catalytic mechanisms of keratinases. Strategies for the molecular modification of keratinases are summarized and discussed in terms of improving the substrate specificity, thermostability, and pH tolerance of keratinases. The modification strategies are also enriched by the introduction of immobilized enzymes and directed evolution. In addition, the selection of modification strategies when facing specific industrial applications is discussed and prospects are provided. We believe that this review serves as a reference for the future quest to extend the application of keratinases from the laboratory to industry.
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Affiliation(s)
- Mingchen Yan
- School of the Life Sciences, Jiangsu University, Zhenjiang 212000, China
| | - Ying Chen
- School of the Life Sciences, Jiangsu University, Zhenjiang 212000, China
| | - Yong Feng
- School of the Life Sciences, Jiangsu University, Zhenjiang 212000, China
| | - Muhammad Saeed
- School of the Life Sciences, Jiangsu University, Zhenjiang 212000, China
| | - Zhen Fang
- Biofuels Institute, School of the Environment, Jiangsu University, Zhenjiang 212000, China
| | - Wang Zhen
- Biofuels Institute, School of the Environment, Jiangsu University, Zhenjiang 212000, China
| | - Zhong Ni
- School of the Life Sciences, Jiangsu University, Zhenjiang 212000, China
| | - Huayou Chen
- School of the Life Sciences, Jiangsu University, Zhenjiang 212000, China
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2
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Tomar V, Rikkerink EHA, Song J, Sofkova-Bobcheva S, Bus VGM. Structure-Function Characterisation of Eop1 Effectors from the Erwinia-Pantoea Clade Reveals They May Acetylate Their Defence Target through a Catalytic Dyad. Int J Mol Sci 2023; 24:14664. [PMID: 37834112 PMCID: PMC10572645 DOI: 10.3390/ijms241914664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 09/21/2023] [Accepted: 09/25/2023] [Indexed: 10/15/2023] Open
Abstract
The YopJ group of acetylating effectors from phytopathogens of the genera Pseudomonas and Ralstonia have been widely studied to understand how they modify and suppress their host defence targets. In contrast, studies on a related group of effectors, the Eop1 group, lag far behind. Members of the Eop1 group are widely present in the Erwinia-Pantoea clade of Gram-negative bacteria, which contains phytopathogens, non-pathogens and potential biocontrol agents, implying that they may play an important role in agroecological or pathological adaptations. The lack of research in this group of YopJ effectors has left a significant knowledge gap in their functioning and role. For the first time, we perform a comparative analysis combining AlphaFold modelling, in planta transient expressions and targeted mutational analyses of the Eop1 group effectors from the Erwinia-Pantoea clade, to help elucidate their likely activity and mechanism(s). This integrated study revealed several new findings, including putative binding sites for inositol hexakisphosphate and acetyl coenzyme A and newly postulated target-binding domains, and raises questions about whether these effectors function through a catalytic triad mechanism. The results imply that some Eop1s may use a catalytic dyad acetylation mechanism that we found could be promoted by the electronegative environment around the active site.
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Affiliation(s)
- Vishant Tomar
- Mt Albert Research Centre, The New Zealand Institute for Plant and Food Research Limited, Auckland 1025, New Zealand
- School of Agriculture and Environment, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand;
| | - Erik H. A. Rikkerink
- Mt Albert Research Centre, The New Zealand Institute for Plant and Food Research Limited, Auckland 1025, New Zealand
| | - Janghoon Song
- Pear Research Institute, National Institute of Horticultural & Herbal Science, Rural Development Administration, Naju 58216, Republic of Korea
| | - Svetla Sofkova-Bobcheva
- School of Agriculture and Environment, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand;
| | - Vincent G. M. Bus
- Hawkes Bay Research Centre, The New Zealand Institute for Plant and Food Research Limited, Havelock North 4130, New Zealand;
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3
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Sorokin AV, Goncharova SS, Lavlinskaya MS, Holyavka MG, Faizullin DA, Zuev YF, Kondratyev MS, Artyukhov VG. Complexation of Bromelain, Ficin, and Papain with the Graft Copolymer of Carboxymethyl Cellulose Sodium Salt and N-Vinylimidazole Enhances Enzyme Proteolytic Activity. Int J Mol Sci 2023; 24:11246. [PMID: 37511006 PMCID: PMC10379864 DOI: 10.3390/ijms241411246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 07/01/2023] [Accepted: 07/07/2023] [Indexed: 07/30/2023] Open
Abstract
This study investigates the features of interactions between cysteine proteases (bromelain, ficin, and papain) and a graft copolymer of carboxymethyl cellulose sodium salt with N-vinylimidazole. The objective is to understand the influence of this interactions on the proteolytic activity and stability of the enzymes. The enzymes were immobilized through complexation with the carrier. The interaction mechanism was examined using Fourier-transform infrared spectroscopy and flexible molecular docking simulations. The findings reveal that the enzymes interact with the functional groups of the carrier via amino acid residues, resulting in the formation of secondary structure elements and enzyme's active sites. These interactions induce modulation of active site of the enzymes, leading to an enhancement in their proteolytic activity. Furthermore, the immobilized enzymes demonstrate superior stability compared to their native counterparts. Notably, during a 21-day incubation period, no protein release from the conjugates was observed. These results suggest that the complexation of the enzymes with the graft copolymer has the potential to improve their performance as biocatalysts, with applications in various fields such as biomedicine, pharmaceutics, and biotechnology.
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Affiliation(s)
- Andrey V Sorokin
- Biophysics and Biotechnology Department, Voronezh State University, 1 Universitetskaya Square, 394018 Voronezh, Russia
- Bioresource Potential of the Seaside Territory Laboratory, Sevastopol State University, 33 Studencheskaya Street, 299053 Sevastopol, Russia
| | - Svetlana S Goncharova
- Biophysics and Biotechnology Department, Voronezh State University, 1 Universitetskaya Square, 394018 Voronezh, Russia
| | - Maria S Lavlinskaya
- Biophysics and Biotechnology Department, Voronezh State University, 1 Universitetskaya Square, 394018 Voronezh, Russia
- Bioresource Potential of the Seaside Territory Laboratory, Sevastopol State University, 33 Studencheskaya Street, 299053 Sevastopol, Russia
| | - Marina G Holyavka
- Biophysics and Biotechnology Department, Voronezh State University, 1 Universitetskaya Square, 394018 Voronezh, Russia
- Bioresource Potential of the Seaside Territory Laboratory, Sevastopol State University, 33 Studencheskaya Street, 299053 Sevastopol, Russia
| | - Dzhigangir A Faizullin
- Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Center of RAS, 2/31 Lobachevsky Street, 420111 Kazan, Russia
| | - Yuriy F Zuev
- Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Center of RAS, 2/31 Lobachevsky Street, 420111 Kazan, Russia
- Alexander Butlerov Chemical Institute, Kazan Federal University, Kremlevskaya Street 18, 420008 Kazan, Russia
| | - Maxim S Kondratyev
- Biophysics and Biotechnology Department, Voronezh State University, 1 Universitetskaya Square, 394018 Voronezh, Russia
- Institute of Cell Biophysics of the RAS, 3 Institutskaya Street, 142290 Pushchino, Russia
| | - Valeriy G Artyukhov
- Biophysics and Biotechnology Department, Voronezh State University, 1 Universitetskaya Square, 394018 Voronezh, Russia
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4
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Díaz-Cervantes E, Robles J, Solà M, Swart M. The peptide bond rupture mechanism in the serine proteases: an in silico study based on sequential scale models. Phys Chem Chem Phys 2023; 25:8043-8049. [PMID: 36876585 DOI: 10.1039/d2cp04872h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Given the importance of serine proteases for biochemical processes, we have studied the peptide bond rupture mechanism using three sequential scale models as representations of the KLK5 enzyme (a protein overexpressed in ovarian cancer). The first model contains the basic functional groups of the residues that conform to the catalytic triad present in serine proteases; the second model contains some additional residues and, finally, the last representation includes all atoms of the KLK5 protein together with 10.000 explicit water molecules. This separation into three scale models allows us to separate the intrinsic reactivity of the catalytic triad from the process taking place in the enzyme. The methodologies employed in this work include full DFT calculations with a dielectric continuum in the first two models and a multi-level setup with a Quantum Mechanics/Molecular Mechanics (QM/MM) partition in the whole protein system. Our results show that the peptide-bond rupture mechanism is a stepwise process involving two proton transfer reactions. The rate-determining step is the second proton transfer from the imidazole group to the amidic nitrogen of the substrate. In addition, we find that the simplest model does not provide accurate results compared to the full protein system. This can be attributed to the electronic stabilization conferred by the residues around the reaction site. Interestingly, the energy profile obtained with the second scale model with additional residues shows the same trends as the full system and could therefore be considered an appropriate model system. It could be used for studying the peptide bond rupture mechanism in case full QM/MM calculations cannot be performed, or as a rapid tool for screening purposes.
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Affiliation(s)
- Erik Díaz-Cervantes
- Departamento de Alimentos, Centro Interdisciplinario del Noreste, Universidad de Guanajuato, 37975 Tierra Blanca, Guanajuato, Mexico.,Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona, 17003 Girona, Spain.
| | - Juvencio Robles
- Departamento de Farmacia, Universidad de Guanajuato, Noria Alta S/N, Gto. 36050, Guanajuato, Mexico
| | - Miquel Solà
- Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona, 17003 Girona, Spain.
| | - Marcel Swart
- Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona, 17003 Girona, Spain. .,ICREA, Pg. Lluís Companys 23, 08010 Barcelona, Spain
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5
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Gisdon FJ, Bombarda E, Ullmann GM. Serine and Cysteine Peptidases: So Similar, Yet Different. How the Active-Site Electrostatics Facilitates Different Reaction Mechanisms. J Phys Chem B 2022; 126:4035-4048. [PMID: 35609250 DOI: 10.1021/acs.jpcb.2c01484] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The catalytic mechanisms of serine and cysteine peptidases are similar: the proton of the nucleophile (serine or cysteine) is transferred to the catalytic histidine, and the nucleophile attacks the substrate for cleavage. However, they differ in an important aspect: cysteine peptidases form a stable ion-pair intermediate in a stepwise mechanism, while serine peptidases follow a concerted mechanism. While it is known that a positive electrostatic potential at the active site of cysteine peptidases stabilizes the cysteine anion in the ion-pair state, the physical basis of the concerted mechanism of serine peptidases is poorly understood. In this work, we use continuum electrostatic analysis and quantum mechanical/molecular mechanical (QM/MM) simulations to demonstrate that a destabilization of an anionic serine by a negative electrostatic potential in combination with a compact active site geometry facilitates a concerted mechanism in serine peptidases. Moreover, we show that an anionic serine would destabilize the protein significantly compared to an anionic cysteine in cysteine peptidases, which underlines the necessity of a concerted mechanism for serine peptidases. On the basis of our calculations on an inactive serine mutant of a natural cysteine peptidase, we show that the energy barrier for the catalytic mechanism can be substantially decreased by introducing a negative electrostatic potential and by reducing the relevant distances indicating that these parameters are essential for the activity of serine peptidases. Our work demonstrates that the concerted mechanism of serine peptidases represents an evolutionary innovative way to perform catalysis without the energetically expensive need to stabilize the anionic serine. In contrast in cysteine peptidases, the anionic cysteine is energetically easily accessible and it is a very efficient nucleophile, making these peptidases mechanistically simple. However, a cysteine is highly oxygen sensitive, which is problematic in an aerobic environment. On the basis of the analysis in this work, we suggest that serine peptidases represent an oxygen-insensitive alternative to cysteine peptidases.
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Affiliation(s)
- Florian J Gisdon
- Biochemistry, University of Bayreuth, Universitätsstraße 30, BGI, 95447 Bayreuth, Germany.,Computational Biochemistry, University of Bayreuth, Universitätsstraße 30, BGI, 95447 Bayreuth, Germany
| | - Elisa Bombarda
- Computational Biochemistry, University of Bayreuth, Universitätsstraße 30, BGI, 95447 Bayreuth, Germany
| | - G Matthias Ullmann
- Computational Biochemistry, University of Bayreuth, Universitätsstraße 30, BGI, 95447 Bayreuth, Germany
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6
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Phiromphu N, Suramitr S, Chotima R, Boonseng B, Songsasen A, Piyasaengthong A. Azine-hydrazone Tautomerism of Thiazolylazo Pyridine Compound: Synthesis, Structural Determination, and Biological Activities. J Mol Struct 2021. [DOI: 10.1016/j.molstruc.2020.129658] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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7
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Saranya V, Radhika R, Shankar R, Vijayakumar S. In silico studies of the inhibition mechanism of dengue with papain. J Biomol Struct Dyn 2020; 39:1912-1927. [PMID: 32249700 DOI: 10.1080/07391102.2020.1742205] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Dengue virus is becoming a major global disease; the envelope protein is the major target for vaccine development against Dengue. Nowadays, the attention has focused on developing inhibitors based on Papain is a promising target for treating Dengue. In the present work, the theoretical studies of E-protein(Cys74-Glu79;Lys110)…Papain(Cys25, Asn175 and His159) complexes are analysed by Density Functional Theory (M06-2X/cc-pVDZ) method. Among the E-protein(Cys74-Glu79;Lys110)…Papain(Cys25, Asn175 and Hys159) complexes, E-protein(Glu76)…Papain(Cys25) complex has the highest interaction value of -352.22 kcal/mol. Moreover, the natural bond orbital analysis also supports the above results. The 100 ns Molecular Dynamics simulation reveals that, E-protein(Ala54-Ile129)…Papain(Cys25) complex had the lowest root mean square deviation value of 1 Å compared to the E-protein(Ala54-Ile129)… Papain(Asn175 & His159) complexes. The salt bridge formation between the Asp103 and Lys110 residues are the important stabilizing factor in E-protein(Ala54-Ile129)…Papain(Cys25) complex. This result can extend our knowledge of the functional behaviour of Papain and provides structural insight to target Envelope protein as forthcoming drug targets in Dengue.
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8
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Shafee T, Gatti-Lafranconi P, Minter R, Hollfelder F. Handicap-Recover Evolution Leads to a Chemically Versatile, Nucleophile-Permissive Protease. Chembiochem 2015; 16:1866-1869. [PMID: 26097079 PMCID: PMC4576821 DOI: 10.1002/cbic.201500295] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 06/19/2015] [Indexed: 11/25/2022]
Abstract
Mutation of the tobacco etch virus (TEV) protease nucleophile from cysteine to serine causes an approximately ∼104 -fold loss in activity. Ten rounds of directed evolution of the mutant, TEVSer , overcame the detrimental effects of nucleophile exchange to recover near-wild-type activity in the mutant TEVSer X. Rather than respecialising TEV to the new nucleophile, all the enzymes along the evolutionary trajectory also retained the ability to use the original cysteine nucleophile. Therefore the adaptive evolution of TEVSer is paralleled by a neutral trajectory for TEVCys , in which mutations that increase serine nucleophile reactivity hardly affect the reactivity of cysteine. This apparent nucleophile permissiveness explains how nucleophile switches can occur in the phylogeny of the chymotrypsin-like protease PA superfamily. Despite the changed key component of their chemical mechanisms, the evolved variants TEVSer X and TEVCys X have similar activities; this could potentially facilitate escape from adaptive conflict to enable active-site evolution.
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Affiliation(s)
- Thomas Shafee
- Department of Biochemistry, University of Cambridge80 Tennis Court Road, Cambridge, CB2 1GA (UK)
- Antibody Discovery and Protein Engineering, MedImmuneGranta Park, Cambridge, CB21 6GH (UK)
- Present address: La Trobe Institute of Molecular Sciences, La Trobe University, Science DriveMelbourne, Victoria 3086 (Australia)
| | - Pietro Gatti-Lafranconi
- Department of Biochemistry, University of Cambridge80 Tennis Court Road, Cambridge, CB2 1GA (UK)
| | - Ralph Minter
- Antibody Discovery and Protein Engineering, MedImmuneGranta Park, Cambridge, CB21 6GH (UK)
| | - Florian Hollfelder
- Department of Biochemistry, University of Cambridge80 Tennis Court Road, Cambridge, CB2 1GA (UK)
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9
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Selenocysteine robustness versus cysteine versatility: a hypothesis on the evolution of the moonlighting behaviour of peroxiredoxins. Biochem Soc Trans 2015; 42:1768-72. [PMID: 25399604 DOI: 10.1042/bst20140212] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Peroxiredoxins (Prxs) and glutathione peroxidases (Gpxs) provide the majority of peroxides reducing activity in the cytoplasm. Both are peroxidases but differences in the chemical mechanism of reduction of oxidative agents, as well as in the reactivity of the catalytically active residues, confer peculiar features on them. Ultimately, Gpx should be regarded as an efficient peroxides scavenger having a high-reactive selenocysteine (Sec) residue. Prx, by having a low pKa cysteine, is less efficient than Gpx in reduction of peroxides under physiological conditions, but the chemistry of the sulfur together with the peculiar structural arrangement of the active site, in typical Prxs, make it suitable to sense a redox environment and to switch-in-function so as to exert holdase activity under redox-stress conditions. The complex macromolecular assembly would have evolved the chaperone holdase function and the moonlighting behaviour typical of many Prxs.
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10
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Takahashi T, Cheung M, Butterweck T, Schankweiler S, Heller MJ. Quest for a turnover mechanism in peptide-based enzyme mimics. CATAL COMMUN 2015. [DOI: 10.1016/j.catcom.2014.10.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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11
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Russo AT, Malmstrom RD, White MA, Watowich SJ. Structural basis for substrate specificity of alphavirus nsP2 proteases. J Mol Graph Model 2010; 29:46-53. [PMID: 20483643 DOI: 10.1016/j.jmgm.2010.04.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Accepted: 04/18/2010] [Indexed: 11/25/2022]
Abstract
The alphavirus nsP2 protease is essential for correct processing of the alphavirus nonstructural polyprotein (nsP1234) and replication of the viral genome. We have combined molecular dynamics simulations with our structural studies to reveal features of the nsP2 protease catalytic site and S1'-S4 subsites that regulate the specificity of the protease. The catalytic mechanism of the nsP2 protease appears similar to the papain-like cysteine proteases, with the conserved catalytic dyad forming a thiolate-imidazolium ion pair in the nsP2-activated state. Substrate binding likely stabilizes this ion pair. Analysis of bimolecular complexes of Venezuelan equine encephalitis virus (VEEV) nsP2 protease with each of the nsP1234 cleavage sites identified protease residues His(510), Ser(511), His(546) and Lys(706) as critical for cleavage site recognition. Homology modelling and molecular dynamics simulations of diverse alphaviruses and their cognate cleavage site sequences revealed general features of substrate recognition that operate across alphavirus strains as well as strain specific covariance between binding site and cleavage site residues. For instance, compensatory changes occurred in the P3 and S3 subsite residues to maintain energetically favourable complementary binding surfaces. These results help explain how alphavirus nsP2 proteases recognize different cleavage sites within the nonstructural polyprotein and discriminate between closely related cleavage targets.
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Affiliation(s)
- Andrew T Russo
- Department of Biochemistry and Molecular Biology and the Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX 77555-0647, USA
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12
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Ghosh R, Chakraborty S, Chakrabarti C, Dattagupta JK, Biswas S. Structural insights into the substrate specificity and activity of ervatamins, the papain-like cysteine proteases from a tropical plant, Ervatamia coronaria. FEBS J 2007; 275:421-34. [PMID: 18167146 DOI: 10.1111/j.1742-4658.2007.06211.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Multiple proteases of the same family are quite often present in the same species in biological systems. These multiple proteases, despite having high homology in their primary and tertiary structures, show deviations in properties such as stability, activity, and specificity. It is of interest, therefore, to compare the structures of these multiple proteases in a single species to identify the structural changes, if any, that may be responsible for such deviations. Ervatamin-A, ervatamin-B and ervatamin-C are three such papain-like cysteine proteases found in the latex of the tropical plant Ervatamia coronaria, and are known not only for their high stability over a wide range of temperature and pH, but also for variations in activity and specificity among themselves and among other members of the family. Here we report the crystal structures of ervatamin-A and ervatamin-C, complexed with an irreversible inhibitor 1-[l-N-(trans-epoxysuccinyl)leucyl]amino-4-guanidinobutane (E-64), together with enzyme kinetics and molecular dynamic simulation studies. A comparison of these results with the earlier structures helps in a correlation of the structural features with the corresponding functional properties. The specificity constants (k(cat)/K(m)) for the ervatamins indicate that all of these enzymes have specificity for a branched hydrophobic residue at the P2 position of the peptide substrates, with different degrees of efficiency. A single amino acid change, as compared to ervatamin-C, in the S2 pocket of ervatamin-A (Ala67-->Tyr) results in a 57-fold increase in its k(cat)/K(m) value for a substrate having a Val at the P2 position. Our studies indicate a higher enzymatic activity of ervatamin-A, which has been subsequently explained at the molecular level from the three-dimensional structure of the enzyme and in the context of its helix polarizibility and active site plasticity.
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Affiliation(s)
- Raka Ghosh
- Crystallography and Molecular Biology Division, Saha Institute of Nuclear Physics, Kolkata, India
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13
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Dardenne LE, Werneck AS, de Oliveira Neto M, Bisch PM. Electrostatic properties in the catalytic site of papain: A possible regulatory mechanism for the reactivity of the ion pair. Proteins 2003; 52:236-53. [PMID: 12833547 DOI: 10.1002/prot.10368] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We present an analysis of the electrostatic properties in the catalytic site of papain (EC 3.4.22.2), an archetype enzyme of the C1 cysteine proteinase family, and we investigate their possible role in the formation, stabilization and regulation of the Cys25((-))...His159((+)) catalytic ion pair. The electrostatic properties were computed using a reassociation method based in multicentered multipolar expansions obtained from ab initio quantum calculations of overlapping protein fragments. Solvent effects were introduced by coupling the use of multicentered multipolar expansions to two continuum boundary element methods to solve the Poisson and the linearized Poisson-Boltzmann equations. The electrostatic profile found in the proton transfer region of papain showed that this enzyme has a well-defined electrostatic environment to favor the formation and stabilization of the catalytic ion pair. The papain catalytic site electrostatic profile can be considered as an electrostatic fingerprint of the papain family with the following characteristics: (i) the presence of a net electric field highly aligned in the (Cys25)-SG-->(His159)-ND1 direction; (ii) the electrostatic profile has a saddle-point character; (iii) it is basically a local environmental effect. Furthermore, our analysis describes a possible regulatory mechanism (the E(SG-->ND1) attenuation effect) controlling the ion pair reactivity and permits to infer the Asp57 acidic residue as the most probable candidate to act as the electrostatic modulator.
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Affiliation(s)
- Laurent E Dardenne
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro-UFRJ, CCS, Bloco G, Ilha do Fundão, 21949-900 Rio de Janeiro, RJ, Brazil
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14
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Sandy J, Mushtaq A, Kawamura A, Sinclair J, Sim E, Noble M. The structure of arylamine N-acetyltransferase from Mycobacterium smegmatis--an enzyme which inactivates the anti-tubercular drug, isoniazid. J Mol Biol 2002; 318:1071-83. [PMID: 12054803 DOI: 10.1016/s0022-2836(02)00141-9] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Arylamine N-acetyltransferases which acetylate and inactivate isoniazid, an anti-tubercular drug, are found in mycobacteria including Mycobacterium smegmatis and Mycobacterium tuberculosis. We have solved the structure of arylamine N-acetyltransferase from M. smegmatis at a resolution of 1.7 A as a model for the highly homologous NAT from M. tuberculosis. The fold closely resembles that of NAT from Salmonella typhimurium, with a common catalytic triad and domain structure that is similar to certain cysteine proteases. The detailed geometry of the catalytic triad is typical of enzymes which use primary alcohols or thiols as activated nucleophiles. Thermal mobility and structural variations identify parts of NAT which might undergo conformational changes during catalysis. Sequence conservation among eubacterial NATs is restricted to structural residues of the protein core, as well as the active site and a hinge that connects the first two domains of the NAT structure. The structure of M. smegmatis NAT provides a template for modelling the structure of the M. tuberculosis enzyme and for structure-based ligand design as an approach to designing anti-TB drugs.
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Affiliation(s)
- James Sandy
- Department of Pharmacology, University of Oxford, Mansfield Road, OX1 3QT, UK
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15
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Štrajbl M, Florián J, Warshel A. Ab Initio Evaluation of the Free Energy Surfaces for the General Base/Acid Catalyzed Thiolysis of Formamide and the Hydrolysis of Methyl Thiolformate: A Reference Solution Reaction for Studies of Cysteine Proteases. J Phys Chem B 2001. [DOI: 10.1021/jp010279l] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Marek Štrajbl
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-1062
| | - Jan Florián
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-1062
| | - Arieh Warshel
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-1062
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Peptide models XXIII. Conformational model for polar side-chain containing amino acid residues: A comprehensive analysis of RHF, DFT, and MP2 properties of HCO-L-SER-NH2. J Comput Chem 2000. [DOI: 10.1002/(sici)1096-987x(200006)21:8<626::aid-jcc4>3.0.co;2-p] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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