1
|
Castro-Amorim J, Oliveira A, Mukherjee AK, Ramos MJ, Fernandes PA. Unraveling the Reaction Mechanism of Russell's Viper Venom Factor X Activator: A Paradigm for the Reactivity of Zinc Metalloproteinases? J Chem Inf Model 2023. [PMID: 37092784 DOI: 10.1021/acs.jcim.2c01156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
Snake venom metalloproteinases (SVMPs) are important drug targets against snakebite envenoming, the neglected tropical disease with the highest mortality worldwide. Here, we focus on Russell's viper (Daboia russelii), one of the "big four" snakes of the Indian subcontinent that, together, are responsible for ca. 50,000 fatalities annually. The "Russell's viper venom factor X activator" (RVV-X), a highly toxic metalloproteinase, activates the blood coagulation factor X (FX), leading to the prey's abnormal blood clotting and death. Given its tremendous public health impact, the WHO recognized an urgent need to develop efficient, heat-stable, and affordable-for-all small-molecule inhibitors, for which a deep understanding of the mechanisms of action of snake's principal toxins is fundamental. In this study, we determine the catalytic mechanism of RVV-X by using a density functional theory/molecular mechanics (DFT:MM) methodology to calculate its free energy profile. The results showed that the catalytic process takes place via two steps. The first step involves a nucleophilic attack by an in situ generated hydroxide ion on the substrate carbonyl, yielding an activation barrier of 17.7 kcal·mol-1, while the second step corresponds to protonation of the peptide nitrogen and peptide bond cleavage with an energy barrier of 23.1 kcal·mol-1. Our study shows a unique role played by Zn2+ in catalysis by lowering the pKa of the Zn2+-bound water molecule, enough to permit the swift formation of the hydroxide nucleophile through barrierless deprotonation by the formally much less basic Glu140. Without the Zn2+ cofactor, this step would be rate-limiting.
Collapse
Affiliation(s)
- Juliana Castro-Amorim
- LAQV, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, Porto 4169-007, Portugal
| | - Ana Oliveira
- LAQV, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, Porto 4169-007, Portugal
| | - Ashis K Mukherjee
- Institute of Advanced Study in Science and Technology, Vigyan Path Garchuk, Paschim Boragaon, Guwahati 781035, Assam, India
| | - Maria J Ramos
- LAQV, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, Porto 4169-007, Portugal
| | - Pedro A Fernandes
- LAQV, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, Porto 4169-007, Portugal
| |
Collapse
|
2
|
Taleb V, Liao Q, Narimatsu Y, García-García A, Compañón I, Borges RJ, González-Ramírez AM, Corzana F, Clausen H, Rovira C, Hurtado-Guerrero R. Structural and mechanistic insights into the cleavage of clustered O-glycan patches-containing glycoproteins by mucinases of the human gut. Nat Commun 2022; 13:4324. [PMID: 35882872 PMCID: PMC9325726 DOI: 10.1038/s41467-022-32021-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 07/13/2022] [Indexed: 11/09/2022] Open
Abstract
Mucinases of human gut bacteria cleave peptide bonds in mucins strictly depending on the presence of neighboring O-glycans. The Akkermansia muciniphila AM0627 mucinase cleaves specifically in between contiguous (bis) O-glycans of defined truncated structures, suggesting that this enzyme may recognize clustered O-glycan patches. Here, we report the structure and molecular mechanism of AM0627 in complex with a glycopeptide containing a bis-T (Galβ1-3GalNAcα1-O-Ser/Thr) O-glycan, revealing that AM0627 recognizes both the sugar moieties and the peptide sequence. AM0627 exhibits preference for bis-T over bis-Tn (GalNAcα1-O-Ser/Thr) O-glycopeptide substrates, with the first GalNAc residue being essential for cleavage. AM0627 follows a mechanism relying on a nucleophilic water molecule and a catalytic base Glu residue. Structural comparison among mucinases identifies a conserved Tyr engaged in sugar-π interactions in both AM0627 and the Bacteroides thetaiotaomicron BT4244 mucinase as responsible for the common activity of these two mucinases with bis-T/Tn substrates. Our work illustrates how mucinases through tremendous flexibility adapt to the diversity in distribution and patterns of O-glycans on mucins. AM0627 is a bis-O-glycan mucinase that might work in the final steps of mucus degradation, thereby providing a carbon and nitrogen source for Akkermansia muciniphila. Here, the authors provide molecular insights into AM0627 function from X-ray crystallography and computer simulations.
Collapse
Affiliation(s)
- Víctor Taleb
- Institute of Biocomputation and Physics of Complex Systems, University of Zaragoza, Mariano Esquillor s/n, Campus Rio Ebro, Edificio I+D, Zaragoza, Spain
| | - Qinghua Liao
- Departament de Química Inorgánica i Orgánica (Secció de Química Orgánica) and Institut de Química Teorica i Computacional (IQTCUB), Universitat de Barcelona, 08028, Barcelona, Spain
| | - Yoshiki Narimatsu
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Ana García-García
- Institute of Biocomputation and Physics of Complex Systems, University of Zaragoza, Mariano Esquillor s/n, Campus Rio Ebro, Edificio I+D, Zaragoza, Spain
| | - Ismael Compañón
- Departamento de Química, Universidad de La Rioja, Centro de Investigación en Síntesis Química, E-26006, Logroño, Spain
| | - Rafael Junqueira Borges
- Departamento de Biofísica e Farmacologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, Brazil
| | - Andrés Manuel González-Ramírez
- Institute of Biocomputation and Physics of Complex Systems, University of Zaragoza, Mariano Esquillor s/n, Campus Rio Ebro, Edificio I+D, Zaragoza, Spain
| | - Francisco Corzana
- Departamento de Química, Universidad de La Rioja, Centro de Investigación en Síntesis Química, E-26006, Logroño, Spain
| | - Henrik Clausen
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Carme Rovira
- Departament de Química Inorgánica i Orgánica (Secció de Química Orgánica) and Institut de Química Teorica i Computacional (IQTCUB), Universitat de Barcelona, 08028, Barcelona, Spain. .,Institució Catalana de Recerca i Estudis Avancats (ICREA), 08010, Barcelona, Spain.
| | - Ramon Hurtado-Guerrero
- Institute of Biocomputation and Physics of Complex Systems, University of Zaragoza, Mariano Esquillor s/n, Campus Rio Ebro, Edificio I+D, Zaragoza, Spain. .,Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark. .,Fundación ARAID, 50018, Zaragoza, Spain.
| |
Collapse
|
3
|
Enhanced carboxypeptidase efficacies and differentiation of peptide epimers. Anal Biochem 2021; 642:114451. [PMID: 34774536 DOI: 10.1016/j.ab.2021.114451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 10/20/2021] [Accepted: 11/04/2021] [Indexed: 11/24/2022]
Abstract
Carboxypeptidases enzymatically cleaves the peptide bond of C-terminal amino acids within peptides. In humans, it is involved in enzymatic synthesis and maturation of proteins and peptides. Carboxypeptidases A and Y have difficulty hydrolyzing the peptide bond of dipeptides and some other amino acid sequences. Early investigations into different N-blocking groups concluded that larger moieties increased substrate susceptibility to peptide bond hydrolysis with carboxypeptidase. This study conclusively demonstrates that 6-aminoquinoline-N-hydroxysuccimidyl carbamate (AQC) as an N-blocking group greatly enhances substrate hydrolysis with carboxypeptidase. AQC addition to the N-terminus of amino acids and peptides also improves chromatographic peak shape and sensitivities via mass spectrometry detection. These enzymes have been used for amino acid sequence determination prior to the advent of modern proteomics. However, most modern proteomic methods assume that all peptides are comprised of l-amino acids and therefore cannot distinguish L-from d-amino acids within the peptide sequence. The majority of existing methods that allow for chiral differentiation either require synthetic standards or incur racemization in the process. This study highlights the resistance of d-amino acids within peptides to enzymatic hydrolysis by Carboxypeptidase Y. This stereoselectivity may be advantageous when screening low abundance peptide epimers.
Collapse
|
4
|
Elsässer B, Goettig P. Mechanisms of Proteolytic Enzymes and Their Inhibition in QM/MM Studies. Int J Mol Sci 2021; 22:3232. [PMID: 33810118 PMCID: PMC8004986 DOI: 10.3390/ijms22063232] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 02/24/2021] [Accepted: 02/26/2021] [Indexed: 12/11/2022] Open
Abstract
Experimental evidence for enzymatic mechanisms is often scarce, and in many cases inadvertently biased by the employed methods. Thus, apparently contradictory model mechanisms can result in decade long discussions about the correct interpretation of data and the true theory behind it. However, often such opposing views turn out to be special cases of a more comprehensive and superior concept. Molecular dynamics (MD) and the more advanced molecular mechanical and quantum mechanical approach (QM/MM) provide a relatively consistent framework to treat enzymatic mechanisms, in particular, the activity of proteolytic enzymes. In line with this, computational chemistry based on experimental structures came up with studies on all major protease classes in recent years; examples of aspartic, metallo-, cysteine, serine, and threonine protease mechanisms are well founded on corresponding standards. In addition, experimental evidence from enzyme kinetics, structural research, and various other methods supports the described calculated mechanisms. One step beyond is the application of this information to the design of new and powerful inhibitors of disease-related enzymes, such as the HIV protease. In this overview, a few examples demonstrate the high potential of the QM/MM approach for sophisticated pharmaceutical compound design and supporting functions in the analysis of biomolecular structures.
Collapse
Affiliation(s)
| | - Peter Goettig
- Structural Biology Group, Department of Biosciences, University of Salzburg, Billrothstrasse 11, 5020 Salzburg, Austria;
| |
Collapse
|
5
|
Xiong L, Peng M, Zhao M, Liang Z. Truncated Expression of a Carboxypeptidase A from Bovine Improves Its Enzymatic Properties and Detoxification Efficiency of Ochratoxin A. Toxins (Basel) 2020; 12:E680. [PMID: 33137913 PMCID: PMC7692142 DOI: 10.3390/toxins12110680] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 10/23/2020] [Accepted: 10/24/2020] [Indexed: 12/11/2022] Open
Abstract
Ochratoxin A (OTA) is a toxic secondary metabolite produced mainly by Penicillium spp. and Aspergillus spp. and commonly found in foodstuffs and feedstuffs. Carboxypeptidase A (CPA) can hydrolyze OTA into the non-toxic product ochratoxin α, with great potential to realize industrialized production and detoxify OTA in contaminated foods and feeds. This study constructed a P. pastoris expression vector of mature CPA (M-CPA) without propeptide and signal peptide. The results showed that the degradation rate of OTA by M-CPA was up to 93.36%. Its optimum pH was 8, the optimum temperature was 40 °C, the value of Km was 0.126 mmol/L, and the maximum reaction rate was 0.0219 mol/min. Compared with commercial CPA (S-CPA), the recombinant M-CPA had an improve stability, for which its optimum temperature increased by 10 °C and stability at a wide range pH, especially at pH 3-4 and pH 11. M-CPA could effectively degrade OTA in red wine. M-CPA has the potential for industrial applications, such as can be used as a detoxification additive for foods and feeds.
Collapse
Affiliation(s)
- Lu Xiong
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; (L.X.); (M.P.); (M.Z.)
| | - Mengxue Peng
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; (L.X.); (M.P.); (M.Z.)
| | - Meng Zhao
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; (L.X.); (M.P.); (M.Z.)
| | - Zhihong Liang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; (L.X.); (M.P.); (M.Z.)
- The Supervision, Inspection and Testing Center of Genetically Modified Organisms, Ministry of Agriculture, Beijing 100083, China
- Beijing Laboratory for Food Quality and Safety, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
| |
Collapse
|
6
|
Abstract
The mercapturic acid pathway is a major route for the biotransformation of xenobiotic and endobiotic electrophilic compounds and their metabolites. Mercapturic acids (N-acetyl-l-cysteine S-conjugates) are formed by the sequential action of the glutathione transferases, γ-glutamyltransferases, dipeptidases, and cysteine S-conjugate N-acetyltransferase to yield glutathione S-conjugates, l-cysteinylglycine S-conjugates, l-cysteine S-conjugates, and mercapturic acids; these metabolites constitute a "mercapturomic" profile. Aminoacylases catalyze the hydrolysis of mercapturic acids to form cysteine S-conjugates. Several renal transport systems facilitate the urinary elimination of mercapturic acids; urinary mercapturic acids may serve as biomarkers for exposure to chemicals. Although mercapturic acid formation and elimination is a detoxication reaction, l-cysteine S-conjugates may undergo bioactivation by cysteine S-conjugate β-lyase. Moreover, some l-cysteine S-conjugates, particularly l-cysteinyl-leukotrienes, exert significant pathophysiological effects. Finally, some enzymes of the mercapturic acid pathway are described as the so-called "moonlighting proteins," catalytic proteins that exert multiple biochemical or biophysical functions apart from catalysis.
Collapse
Affiliation(s)
- Patrick E Hanna
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN, USA
| | - M W Anders
- Department of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, NY, USA
| |
Collapse
|
7
|
Akparov VK, Timofeev VI, Konstantinova GE, Khaliullin IG, Kuranova IP, Rakitina TV, Švedas V. The nature of the ligand's side chain interacting with the S1'-subsite of metallocarboxypeptidase T (from Thermoactinomyces vulgaris) determines the geometry of the tetrahedral transition complex. PLoS One 2019; 14:e0226636. [PMID: 31887148 PMCID: PMC6937156 DOI: 10.1371/journal.pone.0226636] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 11/27/2019] [Indexed: 01/03/2023] Open
Abstract
The carboxypeptidase T (CPT) from Thermoactinomyces vulgaris has an active site structure and 3D organization similar to pancreatic carboxypeptidases A and B (CPA and CPB), but differs in broader substrate specificity. The crystal structures of CPT complexes with the transition state analogs N-sulfamoyl-L-leucine and N-sulfamoyl-L-glutamate (SLeu and SGlu) were determined and compared with previously determined structures of CPT complexes with N-sulfamoyl-L-arginine and N-sulfamoyl-L-phenylalanine (SArg and SPhe). The conformations of residues Tyr255 and Glu270, the distances between these residues and the corresponding ligand groups, and the Zn-S gap between the zinc ion and the sulfur atom in the ligand's sulfamoyl group that simulates a distance between the zinc ion and the tetrahedral sp3-hybridized carbon atom of the converted peptide bond, vary depending on the nature of the side chain in the substrate's C-terminus. The increasing affinity of CPT with the transition state analogs in the order SGlu, SArg, SPhe, SLeu correlates well with a decreasing Zn-S gap in these complexes and the increasing efficiency of CPT-catalyzed hydrolysis of the corresponding tripeptide substrates (ZAAL > ZAAF > ZAAR > ZAAE). Thus, the side chain of the ligand that interacts with the primary specificity pocket of CPT, determines the geometry of the transition complex, the relative orientation of the bond to be cleaved by the catalytic groups of the active site and the catalytic properties of the enzyme. In the case of CPB, the relative orientation of the catalytic amino acid residues, as well as the distance between Glu270 and SArg/SPhe, is much less dependent on the nature of the corresponding side chain of the substrate. The influence of the nature of the substrate side chain on the structural organization of the transition state determines catalytic activity and broad substrate specificity of the carboxypeptidase T.
Collapse
Affiliation(s)
- Valery Kh. Akparov
- Protein Chemistry Department, Federal Institution "State Research Institute of Genetics and Selection of Industrial Microorganisms of the National Research Center "Kurchatov Institute", Moscow, Russia
- Protein Factory, National Research Centre “Kurchatov Institute”, Moscow, Russia
| | - Vladimir I. Timofeev
- Laboratory of X-ray analysis methods and synchrotron radiation, Shubnikov Institute of Crystallography of Federal Scientific Research Centre “Crystallography and Photonics” of Russian Academy of Sciences, Moscow, Russia
- Kurchatov center of synchrotron-neutron research, National Research Centre “Kurchatov Institute”, Moscow, Russia
| | - Galina E. Konstantinova
- Protein Chemistry Department, Federal Institution "State Research Institute of Genetics and Selection of Industrial Microorganisms of the National Research Center "Kurchatov Institute", Moscow, Russia
| | - Ilyas G. Khaliullin
- Laboratory of ion and molecular physics, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow region, Russia
| | - Inna P. Kuranova
- Laboratory of X-ray analysis methods and synchrotron radiation, Shubnikov Institute of Crystallography of Federal Scientific Research Centre “Crystallography and Photonics” of Russian Academy of Sciences, Moscow, Russia
- Kurchatov center of synchrotron-neutron research, National Research Centre “Kurchatov Institute”, Moscow, Russia
| | - Tatiana V. Rakitina
- Protein Factory, National Research Centre “Kurchatov Institute”, Moscow, Russia
- Laboratory of Hormonal Regulation Proteins, Shemyakin−Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Vytas Švedas
- Faculty of Bioengineering and Bioinformatics, Belozersky Institute of Physicochemical Biology, Lomonosov Moscow State University, Moscow, Russia
| |
Collapse
|
8
|
Yasuda M, Saga Y, Tokunaga T, Itoh S, Aoki S. Stereoselective aldol reactions of dihydroxyacetone derivatives catalyzed by chiral Zn2+ complexes. Tetrahedron 2019. [DOI: 10.1016/j.tet.2018.12.060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
9
|
Mahesh S, Tang KC, Raj M. Amide Bond Activation of Biological Molecules. Molecules 2018; 23:E2615. [PMID: 30322008 PMCID: PMC6222841 DOI: 10.3390/molecules23102615] [Citation(s) in RCA: 103] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 10/09/2018] [Accepted: 10/09/2018] [Indexed: 12/02/2022] Open
Abstract
Amide bonds are the most prevalent structures found in organic molecules and various biomolecules such as peptides, proteins, DNA, and RNA. The unique feature of amide bonds is their ability to form resonating structures, thus, they are highly stable and adopt particular three-dimensional structures, which, in turn, are responsible for their functions. The main focus of this review article is to report the methodologies for the activation of the unactivated amide bonds present in biomolecules, which includes the enzymatic approach, metal complexes, and non-metal based methods. This article also discusses some of the applications of amide bond activation approaches in the sequencing of proteins and the synthesis of peptide acids, esters, amides, and thioesters.
Collapse
Affiliation(s)
- Sriram Mahesh
- Department of Chemistry and Biochemistry, Auburn University, Auburn, AL 36849, USA.
| | - Kuei-Chien Tang
- Department of Chemistry and Biochemistry, Auburn University, Auburn, AL 36849, USA.
| | - Monika Raj
- Department of Chemistry and Biochemistry, Auburn University, Auburn, AL 36849, USA.
| |
Collapse
|
10
|
In silico design of potentially functional artificial metallo-haloalkane dehalogenase containing catalytic zinc. 3 Biotech 2018; 8:314. [PMID: 30023146 DOI: 10.1007/s13205-018-1333-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 07/02/2018] [Indexed: 01/05/2023] Open
Abstract
Artificial metalloenzymes are unique as they combine the good features of homogeneous and enzymatic catalysts, and they can potentially improve some difficult catalytic assays. This study reports a method that can be used to create an artificial metal-binding site prior to proving it to be functional in a wet lab. Haloalkane dehalogenase was grafted into a metal-binding site to form an artificial metallo-haloalkane dehalogenase and was studied for its potential functionalities in silico. Computational protocols regarding dynamic metal docking were studied using native metalloenzymes and functional artificial metalloenzymes. Using YASARA Structure, a simulation box covering template structure was created to be filled with water molecules followed by one mutated water molecule closest to the metal-binding site to metal ion. A simple energy minimization step was subsequently run using an AMBER force field to allow the metal ion to interact with the metal-binding residues. Long molecular dynamic simulation using YASARA Structure was performed to analyze the stability of the metal-binding site and the distance between metal-binding residues. Metal ions fluctuating around 2.0 Å across a 20 ns simulation indicated a stable metal-binding site. Metal-binding energies were predicted using FoldX, with a native metalloenzyme (carbonic anhydrase) scoring 18.0 kcal/mol and the best mutant model (C1a) scoring 16.4 kcal/mol. Analysis of the metal-binding site geometry was performed using CheckMyMetal, and all scores for the metalloenzymes and mutant models were in an acceptable range. Like native metalloenzymes, the metal-binding site of C1a was supported by residues in the second coordination shell to maintain a more coordinated metal-binding site. Short-chain multihalogenated alkanes (1,2-dibromoethane and 1,2,3-trichloropropane) were able to dock in the active site of C1a. The halides of the substrate were in contact with both the metal and halide-stabilizing residues, thus indicating a better stabilization of the substrate. The simple catalytic mechanism proposed is that the metal ion interacted with halogen and polarized the carbon-halogen bond, thus making the alpha carbon susceptible to attack by nucleophilic hydroxide. The interaction between halogen in the metal ion and halide-stabilizing residues may help to improve the stabilization of the substrate-enzyme complex and reduce the activation energy. This study reports a modified dynamic metal-docking protocol and validation tests to verify the metal-binding site. These approaches can be applied to design different kinds of artificial metalloenzymes or metal-binding sites.
Collapse
|
11
|
Valdez CE, Morgenstern A, Eberhart ME, Alexandrova AN. Predictive methods for computational metalloenzyme redesign - a test case with carboxypeptidase A. Phys Chem Chem Phys 2018; 18:31744-31756. [PMID: 27841396 DOI: 10.1039/c6cp02247b] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Computational metalloenzyme design is a multi-scale problem. It requires treating the metal coordination quantum mechanically, extensive sampling of the protein backbone, and additionally accounting for the polarization of the active site by both the metal cation and the surrounding protein (a phenomenon called electrostatic preorganization). We bring together a combination of theoretical methods that jointly offer these desired qualities: QM/DMD for mixed quantum-classical dynamic sampling, quantum theory of atoms in molecules (QTAIM) for the assessment of electrostatic preorganization, and Density Functional Theory (DFT) for mechanistic studies. Within this suite of principally different methods, there are both complementarity of capabilities and cross-validation. Using these methods, predictions can be made regarding the relative activities of related enzymes, as we show on the native Zn2+-dependent carboxypeptidase A (CPA), and its mutant proteins, which are hypothesized to hydrolyze modified substrates. For the native CPA, we replicated the catalytic mechanism and the rate in close agreement with the experiment, giving validity to the QM/DMD predicted structure, the DFT mechanism, and the QTAIM assessment of catalytic activity. For most sequences of the modified substrate and tried CPA mutants, substantially worsened activity is predicted. However, for the substrate mutant that contains Asp instead of Phe at the C-terminus, one CPA mutant exhibits a reasonable activity, as predicted across the theoretical methods. CPA is a well-studied system, and here it serves as a testing ground for the offered methods.
Collapse
Affiliation(s)
- Crystal E Valdez
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA.
| | - Amanda Morgenstern
- Molecular Theory Group, Colorado School of Mines, Golden, Colorado 80401, USA.
| | - Mark E Eberhart
- Molecular Theory Group, Colorado School of Mines, Golden, Colorado 80401, USA.
| | - Anastassia N Alexandrova
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA. and California NanoSystems Institute, Los Angeles, CA 90095, USA
| |
Collapse
|
12
|
Jitonnom J, Mujika JI, van der Kamp MW, Mulholland AJ. Quantum Mechanics/Molecular Mechanics Simulations Identify the Ring-Opening Mechanism of Creatininase. Biochemistry 2017; 56:6377-6388. [PMID: 29140090 DOI: 10.1021/acs.biochem.7b01032] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Creatininase catalyzes the conversion of creatinine (a biosensor for kidney function) to creatine via a two-step mechanism: water addition followed by ring opening. Water addition is common to other known cyclic amidohydrolases, but the precise mechanism for ring opening is still under debate. The proton donor in this step is either His178 or a water molecule bound to one of the metal ions, and the roles of His178 and Glu122 are unclear. Here, the two possible reaction pathways have been fully examined by means of combined quantum mechanics/molecular mechanics simulations at the SCC-DFTB/CHARMM22 level of theory. The results indicate that His178 is the main catalytic residue for the whole reaction and explain its role as proton shuttle during the ring-opening step. In the first step, His178 provides electrostatic stabilization to the gem-diolate tetrahedral intermediate. In the second step, His178 abstracts the hydroxyl proton of the intermediate and delivers it to the cyclic amide nitrogen, leading to ring opening. The latter is the rate-limiting step with a free energy barrier of 18.5 kcal/mol, in agreement with the experiment. We find that Glu122 must be protonated during the enzyme reaction, so that it can form a stable hydrogen bond with its neighboring water molecule. Simulations of the E122Q mutant showed that this replacement disrupts the H-bond network formed by three conserved residues (Glu34, Ser78, and Glu122) and water, increasing the energy barrier. Our computational studies provide a comprehensive explanation for previous structural and kinetic observations, including why the H178A mutation causes a complete loss of activity but the E122Q mutation does not.
Collapse
Affiliation(s)
- Jitrayut Jitonnom
- Division of Chemistry, School of Science, University of Phayao , Phayao 56000, Thailand
| | - Jon I Mujika
- Kimika Fakultatea, Euskal Herriko Unibertsitatea UPV/EHU, and Donostia International Physics Center (DIPC) , P.K. 1072, 20080 Donostia, Euskadi, Spain
| | - Marc W van der Kamp
- School of Biochemistry, University of Bristol , Biomedical Sciences Building, University Walk, Bristol BS8 1TD, U.K
- Centre for Computational Chemistry, School of Chemistry, University of Bristol , Bristol BS8 1TS, U.K
| | - Adrian J Mulholland
- Centre for Computational Chemistry, School of Chemistry, University of Bristol , Bristol BS8 1TS, U.K
| |
Collapse
|
13
|
Levytskyy RM, Bohovych I, Khalimonchuk O. Metalloproteases of the Inner Mitochondrial Membrane. Biochemistry 2017; 56:4737-4746. [PMID: 28806058 DOI: 10.1021/acs.biochem.7b00663] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The inner mitochondrial membrane (IM) is among the most protein-rich cellular compartments. The metastable IM subproteome where the concentration of proteins is approaching oversaturation creates a challenging protein folding environment with a high probability of protein malfunction or aggregation. Failure to maintain protein homeostasis in such a setting can impair the functional integrity of the mitochondria and drive clinical manifestations. The IM is equipped with a series of highly conserved, proteolytic complexes dedicated to the maintenance of normal protein homeostasis within this mitochondrial subcompartment. Particularly important is a group of membrane-anchored metallopeptidases commonly known as m-AAA and i-AAA proteases, and the ATP-independent Oma1 protease. Herein, we will summarize the current biochemical knowledge of these proteolytic machines and discuss recent advances in our understanding of mechanistic aspects of their functioning.
Collapse
Affiliation(s)
- Roman M Levytskyy
- Department of Biochemistry, University of Nebraska-Lincoln , Lincoln, Nebraska 68588-0664, United States
| | - Iryna Bohovych
- Department of Biochemistry, University of Nebraska-Lincoln , Lincoln, Nebraska 68588-0664, United States
| | - Oleh Khalimonchuk
- Department of Biochemistry, University of Nebraska-Lincoln , Lincoln, Nebraska 68588-0664, United States.,Nebraska Redox Biology Center, University of Nebraska-Lincoln , Lincoln, Nebraska 68588-0662, United States.,Fred & Pamela Buffett Cancer Center , Omaha, Nebraska 68106, United States
| |
Collapse
|
14
|
Mazurkewich S, Brott AS, Kimber MS, Seah SYK. Structural and Kinetic Characterization of the 4-Carboxy-2-hydroxymuconate Hydratase from the Gallate and Protocatechuate 4,5-Cleavage Pathways of Pseudomonas putida KT2440. J Biol Chem 2016; 291:7669-86. [PMID: 26867578 PMCID: PMC4817193 DOI: 10.1074/jbc.m115.682054] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 02/03/2016] [Indexed: 11/06/2022] Open
Abstract
The bacterial catabolism of lignin and its breakdown products is of interest for applications in industrial processing of ligno-biomass. The gallate degradation pathway ofPseudomonas putidaKT2440 requires a 4-carboxy-2-hydroxymuconate (CHM) hydratase (GalB), which has a 12% sequence identity to a previously identified CHM hydratase (LigJ) fromSphingomonassp. SYK-6. The structure of GalB was determined and found to be a member of the PIG-LN-acetylglucosamine deacetylase family; GalB is structurally distinct from the amidohydrolase fold of LigJ. LigJ has the same stereospecificity as GalB, providing an example of convergent evolution for catalytic conversion of a common metabolite in bacterial aromatic degradation pathways. Purified GalB contains a bound Zn(2+)cofactor; however the enzyme is capable of using Fe(2+)and Co(2+)with similar efficiency. The general base aspartate in the PIG-L deacetylases is an alanine in GalB; replacement of the alanine with aspartate decreased the GalB catalytic efficiency for CHM by 9.5 × 10(4)-fold, and the variant enzyme did not have any detectable hydrolase activity. Kinetic analyses and pH dependence studies of the wild type and variant enzymes suggested roles for Glu-48 and His-164 in the catalytic mechanism. A comparison with the PIG-L deacetylases led to a proposed mechanism for GalB wherein Glu-48 positions and activates the metal-ligated water for the hydration reaction and His-164 acts as a catalytic acid.
Collapse
Affiliation(s)
- Scott Mazurkewich
- From the Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Ashley S Brott
- From the Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Matthew S Kimber
- From the Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Stephen Y K Seah
- From the Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| |
Collapse
|
15
|
Factors affecting the activation and inhibition of intracellular enzymes for degradation of 1,2 diamino benzene: kinetics and thermodynamic studies. Bioprocess Biosyst Eng 2015; 38:2221-30. [PMID: 26334986 DOI: 10.1007/s00449-015-1460-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2015] [Accepted: 08/13/2015] [Indexed: 10/23/2022]
Abstract
Citrobacter freundii, the bacterium isolated from marine sediments was capable of degrading 1,2 diamino benzene (DAB), an endocrine disruptor. The mixed intracellular enzymes from C. freundii were extracted and purified. The mixed intracellular enzymes were used for the degradation of DAB and degree of degradation was evaluated in terms of pyruvic acid, the end product, formed. The variables such as effect of pH, temperature and metal ions on the degradation of DAB using mixed intracellular enzymes (MICE) were investigated. The maximum amount of pyruvic acid formed was found to be 569 ± 5 µg with 96% degradation efficiency at pH 7; temperature 25 °C; zinc nitrate 0.1 mM; and copper sulphate ions 0.15 mM. The stability of MICE at different temperatures and the interaction of MICE with metal ions were confirmed using FT-IR spectroscopy. The formation of pyruvic acid from degradation of DAB followed pseudo-second-order rate kinetics and it was a spontaneous, exothermic process. The activation energy of degradation of DAB by MICE was found to be 82.55 kJ/mol.
Collapse
|
16
|
|
17
|
Miller RE, Lu Y, Tortorella MD, Malfait AM. Genetically Engineered Mouse Models Reveal the Importance of Proteases as Osteoarthritis Drug Targets. Curr Rheumatol Rep 2014; 15:350. [PMID: 23926636 DOI: 10.1007/s11926-013-0350-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
More than two decades of research has revealed a combination of proteases that determine cartilage degradation in osteoarthritis. These include metalloproteinases, which degrade the major macromolecules in cartilage, aggrecan and type II collagen, serine proteases, and cysteine proteases, for example cathepsin K. This review summarizes the function of proteases in osteoarthritis progression, as revealed by studies of genetically engineered mouse models. A brief overview of the biochemical characteristics and features of several important proteases is provided, with the objective of increasing understanding of their function. Published data reveal at least three enzymes to be major targets for osteoarthritis drug development: ADAMTS-5, MMP-13, and cathepsin K. In surgical models of osteoarthritis, mice lacking these enzymes are protected from cartilage damage and, to varying degrees, from bone changes. In-vivo studies targeting these proteases with selective small-molecule inhibitors have been performed for a variety of animal models. Mouse models will provide opportunities for future tests of the therapeutic effect of protease inhibitors, both on progression of structural damage to the joint and on associated pain.
Collapse
Affiliation(s)
- Rachel E Miller
- Department of Medicine, Section of Rheumatology, Rush University Medical Center, 1611 W. Harrison St., Suite 510, Chicago, IL 60612, USA
| | | | | | | |
Collapse
|
18
|
Quantum chemical study of silanediols as metal binding groups for metalloprotease inhibitors. J Mol Model 2013; 19:1819-34. [DOI: 10.1007/s00894-012-1745-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Accepted: 12/18/2012] [Indexed: 11/27/2022]
|
19
|
Bruschi M, Bertini L, Bonačić-Koutecký V, De Gioia L, Mitrić R, Zampella G, Fantucci P. Speciation of Copper–Peptide Complexes in Water Solution Using DFTB and DFT Approaches: Case of the [Cu(HGGG)(Py)] Complex. J Phys Chem B 2012; 116:6250-60. [DOI: 10.1021/jp210409c] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Maurizio Bruschi
- Department of Environmental Science, University of Milano-Bicocca, Piazza della Scienza
1, I-20126 Milano, Italy
| | - Luca Bertini
- Department of Biotechnologies
and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, I-20126 Milano, Italy
| | - Vlasta Bonačić-Koutecký
- Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse
2, D-12489 Berlin, Germany
| | - Luca De Gioia
- Department of Biotechnologies
and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, I-20126 Milano, Italy
| | - Roland Mitrić
- Fachbereich Physik, Freie Universität zu Berlin, Arnimallee 14,
D-14195 Berlin, Germany
| | - Giuseppe Zampella
- Department of Biotechnologies
and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, I-20126 Milano, Italy
| | - Piercarlo Fantucci
- Department of Biotechnologies
and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, I-20126 Milano, Italy
| |
Collapse
|
20
|
A general acid–general base reaction mechanism for human brain aspartoacylase: A QM/MM study. COMPUT THEOR CHEM 2012. [DOI: 10.1016/j.comptc.2011.11.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
21
|
Wu S, Zhang C, Cao R, Xu D, Guo H. pH-Dependent reactivity for glycyl-L-tyrosine in carboxypeptidase-A-catalyzed hydrolysis. J Phys Chem B 2011; 115:10360-7. [PMID: 21732684 DOI: 10.1021/jp2046504] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The dipeptide glycyl-L-tyrosine (GY) can be either a substrate for carboxypeptidase A (CPA) or an inhibitor, depending on pH. In this work, we investigate the pH-dependent reactivity of this dipeptide in CPA-catalyzed hydrolysis using a combined quantum mechanical and molecular mechanical method. It is shown that the monoionic form of the dipeptide, prevalent at high pH, chelates the active site zinc ion, rendering the enzyme inactive. This inhibitory form is consistent with an earlier X-ray structure of the CPA-GY complex. On the other hand, the prevailing di-ionic form of the dipeptide at low pH was found to undergo hydrolysis via a nucleophilic mechanism, leading to an acyl-enzyme complex. The stability of this reaction intermediate is consistent with previous low-temperature solid-state NMR results. The calculated overall free-energy barrier of 20.1 kcal/mol is in excellent agreement with the experimental value of 19.9 kcal/mol.
Collapse
Affiliation(s)
- Shanshan Wu
- College of Chemistry, MOE Key Laboratory of Green Chemistry, Sichuan University, Chengdu, Sichuan 610064, People's Republic of China
| | | | | | | | | |
Collapse
|
22
|
Shushanyan M, Khoshtariya DE, Tretyakova T, Makharadze M, van Eldik R. Diverse role of conformational dynamics in carboxypeptidase A-driven peptide and ester hydrolyses: Disclosing the “Perfect Induced Fit” and “Protein Local Unfolding” pathways by altering protein stability. Biopolymers 2011; 95:852-70. [DOI: 10.1002/bip.21688] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Accepted: 06/05/2011] [Indexed: 11/11/2022]
|
23
|
Wang X, Wu S, Xu D, Xie D, Guo H. Inhibitor and substrate binding by angiotensin-converting enzyme: quantum mechanical/molecular mechanical molecular dynamics studies. J Chem Inf Model 2011; 51:1074-82. [PMID: 21520937 DOI: 10.1021/ci200083f] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Angiotensin-converting enzyme (ACE) is an important zinc-dependent hydrolase responsible for converting the inactive angiotensin I to the vasoconstrictor angiotensin II and for inactivating the vasodilator bradykinin. However, the substrate binding mode of ACE has not been completely understood. In this work, we propose a model for an ACE Michaelis complex based on two known X-ray structures of inhibitor-enzyme complexes. Specifically, the human testis angiotensin-converting enzyme (tACE) complexed with two clinic drugs were first investigated using a combined quantum mechanical and molecular mechanical (QM/MM) approach. The structural parameters obtained from the 550 ps molecular dynamics simulations are in excellent agreement with the X-ray structures, validating the QM/MM approach. Based on these structures, a model for the Michaelis complex was proposed and simulated using the same computational protocol. Implications to ACE catalysis are discussed.
Collapse
Affiliation(s)
- Xuemei Wang
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University , Chengdu, Sichuan 610064, China
| | | | | | | | | |
Collapse
|