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Van Elzen R, Konijnenberg A, Van der Veken P, Edgeworth MJ, Scrivens JH, Fülöp V, Sobott F, Lambeir AM. Study of the Conformational Dynamics of Prolyl Oligopeptidase by Mass Spectrometry: Lessons Learned. J Med Chem 2024; 67:10436-10446. [PMID: 38783480 PMCID: PMC11215766 DOI: 10.1021/acs.jmedchem.4c00866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Revised: 05/14/2024] [Accepted: 05/16/2024] [Indexed: 05/25/2024]
Abstract
Ion mobility mass spectrometry (IM-MS) can be used to analyze native proteins according to their size and shape. By sampling individual molecules, it allows us to study mixtures of conformations, as long as they have different collision cross sections and maintain their native conformation after dehydration and vaporization in the mass spectrometer. Even though conformational heterogeneity of prolyl oligopeptidase has been demonstrated in solution, it is not detectable in IM-MS. Factors that affect the conformation in solution, binding of an active site ligand, the stabilizing Ser554Ala mutation, and acidification do not qualitatively affect the collision-induced unfolding pattern. However, measuring the protection of accessible cysteines upon ligand binding provides a principle for the development of MS-based ligand screening methods.
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Affiliation(s)
- Roos Van Elzen
- Laboratory
of Medical Biochemistry, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Albert Konijnenberg
- Laboratory
of Biomolecular & Analytical Mass Spectrometry, Department of
Chemistry, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium
| | - Pieter Van der Veken
- Laboratory
of Medicinal Chemistry, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Matthew J. Edgeworth
- Waters/Warwick
Centre for BioMedical Mass Spectrometry and Proteomics, School of
Life Sciences, University of Warwick, Coventry CV4 7AL, U.K.
| | - James H. Scrivens
- Waters/Warwick
Centre for BioMedical Mass Spectrometry and Proteomics, School of
Life Sciences, University of Warwick, Coventry CV4 7AL, U.K.
| | - Vilmos Fülöp
- School
of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, U.K.
- Institute
of Biochemistry and Medical Chemistry, Medical School, University of Pécs, 7624 Pécs, Hungary
| | - Frank Sobott
- Laboratory
of Biomolecular & Analytical Mass Spectrometry, Department of
Chemistry, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium
- Astbury
Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, U.K.
- School
of Molecular and Cellular Biology, University
of Leeds, Leeds LS2 9JT, U.K.
| | - Anne-Marie Lambeir
- Laboratory
of Medical Biochemistry, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
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2
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Osorio CE, Wen N, Mejías JH, Mitchell S, von Wettstein D, Rustgi S. Directed-Mutagenesis of Flavobacterium meningosepticum Prolyl-Oligopeptidase and a Glutamine-Specific Endopeptidase From Barley. Front Nutr 2020; 7:11. [PMID: 32133368 PMCID: PMC7040222 DOI: 10.3389/fnut.2020.00011] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 01/28/2020] [Indexed: 12/12/2022] Open
Abstract
Wheat gluten proteins are the known cause of celiac disease. The repetitive tracts of proline and glutamine residues in these proteins make them exceptionally resilient to digestion in the gastrointestinal tract. These indigested peptides trigger immune reactions in susceptible individuals, which could be either an allergic reaction or celiac disease. Gluten exclusion diet is the only approved remedy for such disorders. Recently, a combination of a glutamine specific endoprotease from barley (EP-B2), and a prolyl endopeptidase from Flavobacterium meningosepticum (Fm-PEP), when expressed in the wheat endosperm, were shown to reasonably detoxify immunogenic gluten peptides under simulated gastrointestinal conditions. However useful, these "glutenases" are limited in application due to their denaturation at high temperatures, which most of the food processes require. Variants of these enzymes from thermophilic organisms exist, but cannot be applied directly due to their optimum activity at temperatures higher than 37°C. Though, these enzymes can serve as a reference to guide the evolution of peptidases of mesophilic origin toward thermostability. Therefore, a sequence guided site-saturation mutagenesis approach was used here to introduce mutations in the genes encoding Fm-PEP and EP-B2. A thermostable variant of Fm-PEP capable of surviving temperatures up to 90°C and EP-B2 variant with a thermostability of up 60°C were identified using this approach. However, the level of thermostability achieved is not sufficient; the present study has provided evidence that the thermostability of glutenases can be improved. And this pilot study has paved the way for more detailed structural studies in the future to obtain variants of Fm-PEP and EP-B2 that can survive temperatures ~100°C to allow their packing in grains and use of such grains in the food industry.
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Affiliation(s)
- Claudia E. Osorio
- Department of Crop and Soil Sciences, Washington State University, Pullman, WA, United States
- Agriaquaculture Nutritional Genomic Center, Temuco, Chile
| | - Nuan Wen
- Department of Crop and Soil Sciences, Washington State University, Pullman, WA, United States
| | - Jaime H. Mejías
- Centro Regional de Investigación Carillanca, Instituto de Investigaciones Agropecuarias INIA, Temuco, Chile
| | - Shannon Mitchell
- Department of Biological Systems Engineering, Washington State University, Pullman, WA, United States
| | - Diter von Wettstein
- Department of Crop and Soil Sciences, Washington State University, Pullman, WA, United States
| | - Sachin Rustgi
- Department of Crop and Soil Sciences, Washington State University, Pullman, WA, United States
- Department of Plant and Environmental Sciences, Clemson University Pee Dee Research and Education Center, Florence, SC, United States
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3
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Bauer TL, Buchholz PCF, Pleiss J. The modular structure of α/β-hydrolases. FEBS J 2019; 287:1035-1053. [PMID: 31545554 DOI: 10.1111/febs.15071] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 08/15/2019] [Accepted: 09/19/2019] [Indexed: 12/22/2022]
Abstract
The α/β-hydrolase fold family is highly diverse in sequence, structure and biochemical function. To investigate the sequence-structure-function relationships, the Lipase Engineering Database (https://led.biocatnet.de) was updated. Overall, 280 638 protein sequences and 1557 protein structures were analysed. All α/β-hydrolases consist of the catalytically active core domain, but they might also contain additional structural modules, resulting in 12 different architectures: core domain only, additional lids at three different positions, three different caps, additional N- or C-terminal domains and combinations of N- and C-terminal domains with caps and lids respectively. In addition, the α/β-hydrolases were distinguished by their oxyanion hole signature (GX-, GGGX- and Y-types). The N-terminal domains show two different folds, the Rossmann fold or the β-propeller fold. The C-terminal domains show a β-sandwich fold. The N-terminal β-propeller domain and the C-terminal β-sandwich domain are structurally similar to carbohydrate-binding proteins such as lectins. The classification was applied to the newly discovered polyethylene terephthalate (PET)-degrading PETases and MHETases, which are core domain α/β-hydrolases of the GX- and the GGGX-type respectively. To investigate evolutionary relationships, sequence networks were analysed. The degree distribution followed a power law with a scaling exponent γ = 1.4, indicating a highly inhomogeneous network which consists of a few hubs and a large number of less connected sequences. The hub sequences have many functional neighbours and therefore are expected to be robust toward possible deleterious effects of mutations. The cluster size distribution followed a power law with an extrapolated scaling exponent τ = 2.6, which strongly supports the connectedness of the sequence space of α/β-hydrolases. DATABASE: Supporting data about domains from other proteins with structural similarity to the N- or C-terminal domains of α/β-hydrolases are available in Data Repository of the University of Stuttgart (DaRUS) under doi: https://doi.org/10.18419/darus-458.
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Affiliation(s)
- Tabea L Bauer
- Institute of Biochemistry and Technical Biochemistry, University of Stuttgart, Germany
| | - Patrick C F Buchholz
- Institute of Biochemistry and Technical Biochemistry, University of Stuttgart, Germany
| | - Jürgen Pleiss
- Institute of Biochemistry and Technical Biochemistry, University of Stuttgart, Germany
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4
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Dynamics and ligand-induced conformational changes in human prolyl oligopeptidase analyzed by hydrogen/deuterium exchange mass spectrometry. Sci Rep 2017; 7:2456. [PMID: 28550305 PMCID: PMC5446394 DOI: 10.1038/s41598-017-02550-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 04/12/2017] [Indexed: 11/08/2022] Open
Abstract
Prolyl oligopeptidase (PREP) is conserved in many organisms across life. It is involved in numerous processes including brain function and neuropathology, that require more than its strict proteolytic role. It consists of a seven-bladed β-propeller juxtaposed to a catalytic α/β-hydrolase domain. The conformational dynamics of PREP involved in domain motions and the gating mechanism that allows substrate accessibility remain elusive. Here we used Hydrogen Deuterium eXchange Mass Spectrometry (HDX-MS) to derive the first near-residue resolution analysis of global PREP dynamics in the presence or absence of inhibitor bound in the active site. Clear roles are revealed for parts that would be critical for the activation mechanism. In the free state, the inter-domain interface is loose, providing access to the catalytic site. Inhibitor binding "locks" the two domains together exploiting prominent interactions between the loop of the first β-propeller blade and its proximal helix from the α/β-hydrolase domain. Loop A, thought to drive gating, is partially stabilized but remains flexible and dynamic. These findings provide a conformational guide for further dissection of the gating mechanism of PREP, that would impact drug development. Moreover, they offer a structural framework against which to study proteolysis-independent interactions with disordered proteins like α-synuclein involved in neurodegenerative disease.
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Abstract
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Prolyl
oligopeptidase B from Galerina marginata (GmPOPB)
has recently been discovered as a peptidase capable of
breaking and forming peptide bonds to yield a cyclic peptide. Despite
the relevance of prolyl oligopeptidases in human biology and disease,
a kinetic analysis pinpointing rate-limiting steps for a member of
this enzyme family is not available. Macrocyclase enzymes are currently
exploited to produce cyclic peptides with potential therapeutic applications.
Cyclic peptides are promising druglike molecules because of their
stability and conformational rigidity. Here we describe an in-depth
kinetic characterization of a prolyl oligopeptidase acting as a macrocyclase
enzyme. By combining steady-state and pre-steady-state kinetics, we
propose a kinetic sequence in which a step after macrocyclization
limits steady-state turnover. Additionally, product release is ordered,
where the cyclic peptide departs first followed by the peptide tail.
Dissociation of the peptide tail is slow and significantly contributes
to the turnover rate. Furthermore, trapping of the enzyme by the peptide
tail becomes significant beyond initial rate conditions. The presence
of a burst of product formation and a large viscosity effect further
support the rate-limiting nature of a physical step occurring after
macrocyclization. This is the first detailed description of the kinetic
sequence of a macrocyclase enzyme from this class. GmPOPB is among
the fastest macrocyclases described to date, and this work is a necessary
step toward designing broad-specificity efficient macrocyclases.
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Affiliation(s)
- Clarissa M Czekster
- School of Chemistry, Biomedical Sciences Research Complex, University of St Andrews , North Haugh, St Andrews K16 9ST, U.K
| | - James H Naismith
- School of Chemistry, Biomedical Sciences Research Complex, University of St Andrews , North Haugh, St Andrews K16 9ST, U.K.,Biotherapy Centre, Sichuan University , Chengdu, China
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6
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Männistö PT, García-Horsman JA. Mechanism of Action of Prolyl Oligopeptidase (PREP) in Degenerative Brain Diseases: Has Peptidase Activity Only a Modulatory Role on the Interactions of PREP with Proteins? Front Aging Neurosci 2017; 9:27. [PMID: 28261087 PMCID: PMC5306367 DOI: 10.3389/fnagi.2017.00027] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 01/30/2017] [Indexed: 12/14/2022] Open
Abstract
In the aging brain, the correct balance of neural transmission and its regulation is of particular significance, and neuropeptides have a significant role. Prolyl oligopeptidase (PREP) is a protein highly expressed in brain, and evidence indicates that it is related to aging and in neurodegenration. Although PREP is regarded as a peptidase, the physiological substrates in the brain have not been defined, and after intense research, the molecular mechanisms where this protein is involved have not been defined. We propose that PREP functions as a regulator of other proteins though peptide gated direct interaction. We speculate that, at least in some processes where PREP has shown to be relevant, the peptidase activity is only a consequence of the interactions, and not the main physiological activity.
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Affiliation(s)
- Pekka T Männistö
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki Helsinki, Finland
| | - J Arturo García-Horsman
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki Helsinki, Finland
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7
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Portugal B, Motta FN, Correa AF, Nolasco DO, de Almeida H, Magalhães KG, Atta ALV, Vieira FD, Bastos IMD, Santana JM. Mycobacterium tuberculosis Prolyl Oligopeptidase Induces In vitro Secretion of Proinflammatory Cytokines by Peritoneal Macrophages. Front Microbiol 2017; 8:155. [PMID: 28223969 PMCID: PMC5293833 DOI: 10.3389/fmicb.2017.00155] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 01/20/2017] [Indexed: 11/13/2022] Open
Abstract
Tuberculosis (TB) is a disease that leads to death over 1 million people per year worldwide and the biological mediators of this pathology are poorly established, preventing the implementation of effective therapies to improve outcomes in TB. Host-bacterium interaction is a key step to TB establishment and the proteases produced by these microorganisms seem to facilitate bacteria invasion, migration and host immune response evasion. We presented, for the first time, the identification, biochemical characterization, molecular dynamics (MDs) and immunomodulatory properties of a prolyl oligopeptidase (POP) from Mycobacterium tuberculosis (POPMt). POP is a serine protease that hydrolyzes substrates with high specificity for proline residues and has already been characterized as virulence factor in infectious diseases. POPMt reveals catalytic activity upon N-Suc-Gly-Pro-Leu-Gly-Pro-AMC, a recognized POP substrate, with optimal activity at pH 7.5 and 37°C. The enzyme presents KM and Kcat/KM values of 108 μM and 21.838 mM-1 s-1, respectively. MDs showed that POPMt structure is similar to that of others POPs, which consists of a cylindrical architecture divided into an α/β hydrolase catalytic domain and a β-propeller domain. Finally, POPMt was capable of triggering in vitro secretion of proinflammatory cytokines by peritoneal macrophages, an event dependent on POPMt intact structure. Our data suggests that POPMt may contribute to an inflammatory response during M. tuberculosis infection.
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Affiliation(s)
- Brina Portugal
- Pathogen-Host Interface Laboratory, Department of Cell Biology, The University of Brasília, Brasília Brazil
| | - Flávia N Motta
- Pathogen-Host Interface Laboratory, Department of Cell Biology, The University of Brasília, BrasíliaBrazil; Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de GoiásGoiânia, Brazil
| | - Andre F Correa
- Pathogen-Host Interface Laboratory, Department of Cell Biology, The University of Brasília, BrasíliaBrazil; Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de GoiásGoiânia, Brazil
| | - Diego O Nolasco
- Physics Course and Postgraduate Program in Genomic Sciences and Biotechnology, Catholic University of Brasília Brasília, Brazil
| | - Hugo de Almeida
- Pathogen-Host Interface Laboratory, Department of Cell Biology, The University of Brasília, Brasília Brazil
| | - Kelly G Magalhães
- Laboratory of Immunology and Inflammation, Department of Cell Biology, The University of Brasília Brasília, Brazil
| | - Ana L V Atta
- Laboratório Central de Saúde Pública do Distrito Federal Brasília, Brazil
| | - Francisco D Vieira
- Laboratório Central de Saúde Pública do Distrito Federal Brasília, Brazil
| | - Izabela M D Bastos
- Pathogen-Host Interface Laboratory, Department of Cell Biology, The University of Brasília, Brasília Brazil
| | - Jaime M Santana
- Pathogen-Host Interface Laboratory, Department of Cell Biology, The University of Brasília, Brasília Brazil
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8
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The loops facing the active site of prolyl oligopeptidase are crucial components in substrate gating and specificity. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1834:98-111. [DOI: 10.1016/j.bbapap.2012.08.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Revised: 08/04/2012] [Accepted: 08/13/2012] [Indexed: 11/15/2022]
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Kaszuba K, Róg T, Danne R, Canning P, Fülöp V, Juhász T, Szeltner Z, St. Pierre JF, García-Horsman A, Männistö PT, Karttunen M, Hokkanen J, Bunker A. Molecular dynamics, crystallography and mutagenesis studies on the substrate gating mechanism of prolyl oligopeptidase. Biochimie 2012; 94:1398-411. [DOI: 10.1016/j.biochi.2012.03.012] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Accepted: 03/13/2012] [Indexed: 01/10/2023]
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10
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St-Pierre JF, Karttunen M, Mousseau N, Róg T, Bunker A. Use of Umbrella Sampling to Calculate the Entrance/Exit Pathway for Z-Pro-Prolinal Inhibitor in Prolyl Oligopeptidase. J Chem Theory Comput 2011; 7:1583-94. [PMID: 26596426 DOI: 10.1021/ct1007058] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Prolyl oligopeptidase (POP), a member of the prolyl endopeptidase family, is known to play a role in several neurological disorders. Its primary function is to cleave a wide range of small oligopeptides, including neuroactive peptides. We have used force biased molecular dynamics simulation to study the binding mechanism of POP. We examined three possible binding pathways using Steered Molecular Dynamics (SMD) and Umbrella Sampling (US) on a crystal structure of porcine POP with bound Z-pro-prolinal (ZPP). Using SMD, an exit pathway between the first and seventh blade of the β-propeller domain of POP was found to be a nonviable route. US on binding pathways through the β-propeller tunnel and the TYR190-GLN208 flexible loop at the interface between both POP domains allowed us to isolate the flexible loop pathway as the most probable. Further analysis of that pathway suggests a long-range covariation of the interdomain H-bond network, which indicates the possibility of large-scale domain reorientation observed in bacterial homologues and hypothesized to also occur in human POP.
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Affiliation(s)
- Jean-François St-Pierre
- Département de Physique and Regroupement Québécois sur les Matériaux de Pointe, Université de Montréal , C.P. 6128, succursale centre-ville, Montréal (Québec), Canada H3C 3J7
| | - Mikko Karttunen
- Department of Applied Mathematics, The University of Western Ontario , 1151 Richmond Street North, London (Ontario), Canada N6A 5B7
| | - Normand Mousseau
- Département de Physique and Regroupement Québécois sur les Matériaux de Pointe, Université de Montréal , C.P. 6128, succursale centre-ville, Montréal (Québec), Canada H3C 3J7
| | - Tomasz Róg
- Department of Physics, Tampere University of Technology , P.O. Box 692, FI-33101 Tampere, Finland
| | - Alex Bunker
- Centre for Drug Research, Faculty of Pharmacy, University of Helsinki , P.O. Box 56, FI-00014, University of Helsinki, Finland.,Department of Chemistry, Aalto University , PO Box 6100, FI-02015, Aalto, Finland
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11
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Tenorio-Laranga J, Coret-Ferrer F, Casanova-Estruch B, Burgal M, García-Horsman JA. Prolyl oligopeptidase is inhibited in relapsing-remitting multiple sclerosis. J Neuroinflammation 2010; 7:23. [PMID: 20370893 PMCID: PMC2864237 DOI: 10.1186/1742-2094-7-23] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Accepted: 04/06/2010] [Indexed: 12/27/2022] Open
Abstract
Background Multiple sclerosis (MS) is a complex, inflammatory and neurodegenerative disease of the central nervous system leading to long-term disability. Recent studies indicate a close association between inflammation and neurodegeneration in all lesions and disease stages of MS. Prolyl oligopeptidase (POP) is a proline-specific serine protease that cleaves several neuroactive peptides. This peptidase has been implicated in neurodegeneration, as well as in the modulation of the inflammatory response. Methods We examined plasma POP and the levels of an endogenous POP inhibitor from relapsing remitting MS patients and compared these with healthy controls, by monitoring the fluorescent changes due to standard fluorescently labelled substrate cleavage. We analysed the data in relationship to patient age and disease disability status. Results We observed a significant decrease in POP activity in plasma of relapsing remitting MS patients relative to healthy controls, coupled with an increase of POP endogenous inhibitor. The POP activity was also correlated with patient age and disability status. The lowered POP activity from plasma of MS patients could be rescued by reductants Conclusions The decrease in circulating POP activity measured in MS is reverted by reductants. This suggests that POP inactivation in MS might be a result of the oxidative conditions prevailing in the plasma of the diseased patients. Plasma levels of POP activity as well as those of their endogenous inhibitor are suggested as biomarkers of inflammation and oxidative stress in MS.
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Affiliation(s)
- Jofre Tenorio-Laranga
- Department of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
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12
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Kaszuba K, Rog T, St Pierre JF, Mannisto PT, Karttunen M, Bunker A. Molecular dynamics study of prolyl oligopeptidase with inhibitor in binding cavity. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2009; 20:595-609. [PMID: 20024801 DOI: 10.1080/10629360903438198] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We used the crystal structure of prolyl oligopeptidase (POP) with bound Z-pro-prolinal (ZPP) inhibitor (Protein Data Bank (PDB) structure 1QFS) to perform an intensive molecular dynamics study of the POP-ZPP complex. We performed 100 ns of simulation with the hemiacetal bond, through which the ZPP is bound to the POP, removed in order to better investigate the binding cavity environment. From basic analysis, measuring the radius of gyration, root mean square deviation, solvent accessible surface area and definition of the secondary structure of protein, we determined that the protein structure is highly stable and maintains its structure over the entire simulation time. This demonstrates that such long time simulations can be performed without the protein structure losing stability. We found that water bridges and hydrogen bonds play a negligible role in binding the ZPP thus indicating the importance of the hemiacetal bond. The two domains of the protein are bound by a set of approximately 12 hydrogen bonds, specific to the particular POP protein.
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Affiliation(s)
- K Kaszuba
- Department of Physics, Tampere University of Technology, FI-33101 Tampere, Finland
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13
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Oligopeptidase B: A processing peptidase involved in pathogenesis. Biochimie 2008; 90:336-44. [DOI: 10.1016/j.biochi.2007.10.011] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2007] [Accepted: 10/25/2007] [Indexed: 11/20/2022]
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14
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Abstract
The peptidase domain of prolyl oligopeptidase is covered by a propeller domain, which excludes large peptides and proteins from the catalytic triad. Previous studies indicated that some amino acids of the N-terminal region constitute a part of the substrate entrance to the active site. To investigate the catalytic role of the N-terminus, we removed the residues 1-32 from the enzyme and examined the kinetic, thermodynamic, and structural consequences of the deletion, using the thermophile Pyrococcus furiosus prolyl oligopeptidase. An about threefold decrease in the catalytic activity along with a 20 degrees C reduction in the temperature optimum was observed. The pH-rate profile, the rate-limiting step, and the activation parameters did not change significantly. However, a substantial decrease was observed in the stability of the protein as demonstrated by circular dichroism and differential scanning calorimetry measurements, and by denaturation with guanidinium chloride. It was concluded that the N-terminal segment did not facilitate the substrate binding, independent of the size of the substrate, but contributed principally to the protein stability required for the formation of the proper active site.
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Affiliation(s)
- Tünde Juhász
- Institute of Enzymology, Biological Research Center, Hungarian Academy of Sciences, H-1518 Budapest 112, Hungary
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15
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Gorrão SS, Hemerly JP, Lima AR, Melo RL, Szeltner Z, Polgár L, Juliano MA, Juliano L. Fluorescence resonance energy transfer (FRET) peptides and cycloretro-inverso peptides derived from bradykinin as substrates and inhibitors of prolyl oligopeptidase. Peptides 2007; 28:2146-54. [PMID: 17904692 DOI: 10.1016/j.peptides.2007.08.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2007] [Revised: 08/17/2007] [Accepted: 08/17/2007] [Indexed: 10/22/2022]
Abstract
Prolyl oligopeptidase (POP, EC 3.4.21.26) is a member of a family of serine peptidases with post-proline cleaving activity towards peptides. It is located in the cytosol in active form but without hydrolytic activity on proteins or peptides higher than 30 amino acids. Its function is not well defined, but it is involved in central nervous system disorders. Here, we studied the substrate specificity of wild type POP (POPwt) and its C255T variant lacking the non-catalytic Cys(255). This residue is located in the seven-bladed beta-propeller domain that regulates the activity of POP. Fluorescence resonance energy transfer (FRET) peptides were used with sequences derived from bradykinin-containing region of human kininogen and flanked by Abz (ortho-aminobenzoic acid) and EDDnp [N-ethylenediamine-(2,4-dinitrophenyl)]. The peptide Abz-GFSPFRQ-EDDnp was taken as leader substrate for the synthesis of five series of peptides modified at the P(3), P(2), P'(1), P'(2) and P'(3) residues. The optimal amino acids in each position for POPwt resulted in the sequence RRPYIR that is very similar to the C-terminal sequence of neurotensin. The cyclic peptides c(G((n))FSPFR) (n=1-4) were hydrolyzed by POP; their cycloretro and cycloretro-inverso analogues were inhibitors in the micromolar range. The differences between POPwt and its C255T mutant in the hydrolysis of the series derived from Abz-GFSPFRQ-EDDnp were restricted to the non-prime site of the substrates. The kinetic data of hydrolysis and inhibition by the cyclic peptides are consistent with the structures of POP-substrate/inhibitor complexes and with the substrate specificity data obtained with linear FRET peptides. All together, these results give information about the POP-substrate/inhibitor interactions that further complete knowledge of this important oligopeptidase.
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Affiliation(s)
- Silvia S Gorrão
- Department of Biophysics, Escola Paulista de Medicina, Rua Três de Maio 100, São Paulo--SP 04044-020, Brazil
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Juhász T, Szeltner Z, Polgár L. Properties of the prolyl oligopeptidase homologue from Pyrococcus furiosus. FEBS Lett 2006; 580:3493-7. [PMID: 16714022 DOI: 10.1016/j.febslet.2006.05.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2006] [Revised: 05/02/2006] [Accepted: 05/08/2006] [Indexed: 10/24/2022]
Abstract
Prolyl oligopeptidase (POP), the paradigm of a serine peptidase family, hydrolyses peptides, but not proteins. The thermophilic POP from Pyrococcus furiosus (Pfu) appeared to be an exception, since it hydrolysed large proteins. Here we demonstrate that the Pfu POP does not display appreciable activity against azocasein. The autolysis observed earlier was an artefact. We have also found that the pH-rate profile is different from that of the mammalian enzyme and the low pK(a) extracted from the curve represents the ionization of the catalytic histidine. We conclude that some oligopeptidases may be true endopeptidases, cleaving at disordered segments of proteins, but with very low efficacy.
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Affiliation(s)
- Tünde Juhász
- Institute of Enzymology, Biological Research Center, Hungarian Academy of Sciences, Budapest
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17
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Nishimura M, Ikeda K, Sugiyama M. Molecular cloning and characterization of gene encoding novel puromycin-inactivating enzyme from blasticidin S-producing Streptomyces morookaensis. J Biosci Bioeng 2006; 101:63-9. [PMID: 16503293 DOI: 10.1263/jbb.101.63] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2005] [Accepted: 10/27/2005] [Indexed: 11/17/2022]
Abstract
Puromycin (PM) is classified into a family of nucleoside antibiotics together with blasticidin S (BS). PM-producing Streptomyces alboniger is known to express a PM-inactivating enzyme as a self-resistance determinant, which catalyzes the acetylation of PM. We have shown that, although BS-producing Streptomyces morookaensis also produces a PM-inactivating enzyme, it catalyzes the hydrolysis of an amide linkage between the aminonucleoside and O-methyl-L-tyrosine moiety of PM. In the present study, we cloned and characterized a gene encoding PM hydrolase (PMH) from BS-producing S. morookaensis JCM4673. The nucleotide sequence analysis suggests that an open reading frame consisting of 1986 bp is a gene for PMH and encodes a protein consisting of 662 amino acids with a calculated molecular mass of 71,260 Da. The molecular mass of the recombinant PMH, which was produced using an Escherichia coli host-vector system, was the same as that of PMH purified from the JCM4673 strain. Our biochemical study of the recombinant PMH confirmed that the enzyme is an aminopeptidase with broad substrate specificity. The putative primary structure of PMH contains a Gly-X-Ser-X-Gly motif, which is commonly observed among serine proteases. In addition, the amino acid sequence of PMH displays a high similarity to that of the Streptomyces acyl-peptide hydrolase (ACPH), which is a member of the prolyl oligopeptidase (POP) family of serine proteases. Furthermore, the catalytic triad (Ser-Asp-His), which is observed in the POP family, is also present in the primary structure of PMH. These results suggest that PMH is an aminopeptidase classified into the POP family.
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Affiliation(s)
- Motohiro Nishimura
- Department of Chemical and Biological Engineering, Ube National College of Technology, 2-14-1 Tokiwadai, Ube, Yamaguchi 755-8555, Japan.
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18
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Morty RE, Shih AY, Fülöp V, Andrews NW. Identification of the reactive cysteine residues in oligopeptidase B from Trypanosoma brucei. FEBS Lett 2005; 579:2191-6. [PMID: 15811340 DOI: 10.1016/j.febslet.2005.03.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2005] [Revised: 03/07/2005] [Accepted: 03/07/2005] [Indexed: 11/28/2022]
Abstract
Oligopeptidase B (OpdB) from Trypanosoma brucei is a candidate therapeutic target in African trypanosomiasis. OpdB is an atypical serine peptidase, since activity is inhibited by thiol-blocking reagents and enhanced by reducing agents. We have identified C256 as the reactive cysteine residue that mediates OpdB inhibition by N-ethylmaleimide and iodoacetic acid. Modeling studies suggest that C256 adducts occlude the P(1) substrate-binding site, preventing substrate binding. We further demonstrate that C559 and C597 are responsible for the thiol-enhancement of OpdB activity. These studies may facilitate the development of specific OpdB inhibitors with therapeutic potential, by exploiting these unique properties of this enzyme.
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Affiliation(s)
- Rory E Morty
- Department of Internal Medicine, University of Giessen School of Medicine, Aulweg 123 (Room 6-11), D-35392 Giessen, Germany.
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19
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Shan L, Marti T, Sollid L, Gray G, Khosla C. Comparative biochemical analysis of three bacterial prolyl endopeptidases: implications for coeliac sprue. Biochem J 2005; 383:311-8. [PMID: 15245330 PMCID: PMC1134072 DOI: 10.1042/bj20040907] [Citation(s) in RCA: 163] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Prolyl endopeptidases have potential for treating coeliac sprue, a disease of the intestine caused by proteolytically resistant peptides from proline-rich prolamins of wheat, barley and rye. We compared the properties of three similar bacterial prolyl endopeptidases, including the known enzymes from Flavobacterium meningosepticum (FM) and Sphingomonas capsulate (SC) and a novel enzyme from Myxococcus xanthus (MX). These enzymes were interrogated with reference chromogenic substrates, as well as two related gluten peptides (PQPQLPYPQPQLP and LQLQPFPQPQLPYPQPQLPYPQPQLPYPQPQPF), believed to play a key role in coeliac sprue pathogenesis. In vitro and in vivo studies were conducted to evaluate the activity, specificity and acid/protease stability of the enzymes. All peptidases were relatively resistant to acid, pancreatic proteases and membrane peptidases of the small intestinal mucosa. Although their activities against reference substrates were similar, the enzymes exhibited substantial differences with respect to chain length and subsite specificity. SC hydrolysed PQPQLPYPQPQLP well, but had negligible activity against LQLQPFPQPQLPYPQPQLPYPQPQLPYPQPQPF. In contrast, the FM and MX peptidases cleaved both substrates, although the FM enzyme acted more rapidly on LQLQPFPQPQLPYPQPQLPYPQPQLPYPQPQPF than MX. Whereas the FM enzyme showed a preference for Pro-Gln bonds, SC cleaved both Pro-Gln and Pro-Tyr bonds with comparable efficiency, and MX had a modest preference for Pro-(Tyr/Phe) sites over Pro-Gln sites. While a more comprehensive understanding of sequence and chain-length specificity may be needed to assess the relative utility of alternative prolyl endopeptidases for treating coeliac sprue, our present work has illustrated the diverse nature of this class of enzymes from the standpoint of proteolysing complex substrates such as gluten.
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Affiliation(s)
- Lu Shan
- *Department of Chemical Engineering, Stanford Unversity, Stanford, CA 94305, U.S.A
| | - Thomas Marti
- †Celiac Sprue Research Foundation, 3181 Porter Drive, Palo Alto, CA 94304, U.S.A
| | - Ludvig M. Sollid
- ‡Institute of Immunology, Rikshospitalet, University of Oslo, N-0027 Oslo, Norway
| | - Gary M. Gray
- †Celiac Sprue Research Foundation, 3181 Porter Drive, Palo Alto, CA 94304, U.S.A
- §Department of Medicine, Stanford Unversity, Stanford, CA 94305, U.S.A
| | - Chaitan Khosla
- *Department of Chemical Engineering, Stanford Unversity, Stanford, CA 94305, U.S.A
- ∥Department of Chemistry, Stanford Unversity, Stanford, CA 94305, U.S.A
- ¶Department of Biochemistry, Stanford Unversity, Stanford, CA 94305, U.S.A
- To whom correspondence should be addressed (email )
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20
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Juhász T, Szeltner Z, Fülöp V, Polgár L. Unclosed β-Propellers Display Stable Structures: Implications for Substrate Access to the Active Site of Prolyl Oligopeptidase. J Mol Biol 2005; 346:907-17. [PMID: 15713471 DOI: 10.1016/j.jmb.2004.12.014] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2004] [Revised: 12/02/2004] [Accepted: 12/06/2004] [Indexed: 10/26/2022]
Abstract
Prolyl oligopeptidase is implicated in the metabolism of neuropeptides and is involved in amnesia and depression. It contains a peptidase and an unusual beta-propeller domain that excludes large peptides and proteins from the active site. The propeller consists of seven blades not closed by a "Velcro" between the first and last blades. The propeller domain was expressed as a stable, soluble protein, P(7). Its conformational identity with that of the native propeller was verified by circular dichroism and digestion with trypsin. Differential scanning calorimetry, kinetic denaturation with urea and equilibrium denaturation with guanidinium chloride have shown that the propeller is more stable than the parent prolyl oligopeptidase. The deletion of the seventh blade of P(7) led to a stable structure, a six-bladed propeller, P(6), which immediately dimerized, in contrast with the monomeric P(7). Addition of an 11 amino acid residue extension to the C terminus of P(6) also produced a dimer, whereas the P(6) labelled with a His-tag at the N terminus displayed a monomer structure. The stability of P(6) and its variants was lower than that of P(7). The denatured propellers refolded readily. This study shows that the unclosed P(7) is a stable structure, and suggests that an opening between the peptidase and the propeller domains is more important for the substrate entry than is the putative opening between the first and seventh blades. Our results suggest that the propellers are simple, versatile structures, which can be prepared artificially.
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Affiliation(s)
- Tünde Juhász
- Institute of Enzymology, Biological Research Center, Hungarian Academy of Sciences, 1113 Karolina ut 29, H-1518 Budapest 112, P.O. Box 7, Hungary
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21
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Szeltner Z, Rea D, Juhász T, Renner V, Fülöp V, Polgár L. Concerted Structural Changes in the Peptidase and the Propeller Domains of Prolyl Oligopeptidase are Required for Substrate Binding. J Mol Biol 2004; 340:627-37. [PMID: 15210359 DOI: 10.1016/j.jmb.2004.05.011] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2004] [Revised: 04/26/2004] [Accepted: 05/07/2004] [Indexed: 10/26/2022]
Abstract
Prolyl oligopeptidase contains a peptidase domain and its catalytic triad is covered by the central tunnel of a seven-bladed beta-propeller. This domain makes the enzyme an oligopeptidase by excluding large structured peptides from the active site. The apparently rigid crystal structure does not explain how the substrate can approach the catalytic groups. Two possibilities of substrate access were investigated: either blades 1 and 7 of the propeller domain move apart, or the peptidase and/or propeller domains move to create an entry site at the domain interface. Engineering disulfide bridges to the expected oscillating structures prevented such movements, which destroyed the catalytic activity and precluded substrate binding. This indicated that concerted movements of the propeller and the peptidase domains are essential for the enzyme action.
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Affiliation(s)
- Zoltán Szeltner
- Institute of Enzymology, Biological Research Center, Hungarian Academy of Sciences, H-1518 Budapest 112, P.O. Box 7, Hungary
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22
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Venäläinen JI, Juvonen RO, Männistö PT. Evolutionary relationships of the prolyl oligopeptidase family enzymes. ACTA ACUST UNITED AC 2004; 271:2705-15. [PMID: 15206935 DOI: 10.1111/j.1432-1033.2004.04199.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The prolyl oligopeptidase (POP) family of serine proteases includes prolyl oligopeptidase, dipeptidyl peptidase IV, acylaminoacyl peptidase and oligopeptidase B. The enzymes of this family specifically hydrolyze oligopeptides with less than 30 amino acids. Many of the POP family enzymes have evoked pharmaceutical interest as they have roles in the regulation of peptide hormones and are involved in a variety of diseases such as dementia, trypanosomiasis and type 2 diabetes. In this study we have clarified the evolutionary relationships of these four POP family enzymes and analyzed POP sequences from different sources. The phylogenetic trees indicate that the four enzymes were present in the last common ancestor of all life forms and that the beta-propeller domain has been part of the family for billions of years. There are striking differences in the mutation rates between the enzymes and POP was found to be the most conserved enzyme of this family. However, the localization of this enzyme has changed throughout evolution, as three archaeal POPs seem to be membrane bound and one third of the bacterial as well as two eukaryotic POPs were found to be secreted out of the cell. There are also considerable distinctions between the mutation rates of the different substrate binding subsites of POP. This information may help in the development of species-specific POP inhibitors.
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23
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Szeltner Z, Rea D, Juhász T, Renner V, Mucsi Z, Orosz G, Fülöp V, Polgár L. Substrate-dependent competency of the catalytic triad of prolyl oligopeptidase. J Biol Chem 2002; 277:44597-605. [PMID: 12228249 DOI: 10.1074/jbc.m207386200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Prolyl oligopeptidase, a serine peptidase unrelated to trypsin and subtilisin, is implicated in memory disorders and is an important target of drug design. The catalytic competence of the Asp(641) residue of the catalytic triad (Ser(554), Asp(641), His(680)) was studied using the D641N and D641A variants of the enzyme. Both variants displayed 3 orders of magnitude reduction in k(cat)/K(m) for benzyloxycarbonyl-Gly-Pro-2-naphthylamide. Using an octapeptide substrate, the decrease was 6 orders of magnitude, whereas with Z-Gly-Pro-4-nitrophenyl ester there was virtually no change in k(cat)/K(m). This indicates that the contribution of Asp(641) is very much dependent on the substrate-leaving group, which was not the case for the classic serine peptidase, trypsin. The rate constant for benzyloxycarbonyl-Gly-Pro-thiobenzylester conformed to this series as demonstrated by a method designed for monitoring the hydrolysis of thiolesters in the presence of thiol groups. Alkylation of His(680) with Z-Gly-Pro-CH(2)Cl was concluded with similar rate constants for wild-type and D641A variant. However, kinetic measurements with Z-Gly-Pro-OH, a product-like inhibitor, indicated that the His(680) is not accessible in the enzyme variants. Crystal structure determination of these mutants revealed subtle perturbations related to the catalytic activity. Many of these observations show differences in the catalysis between trypsin and prolyl oligopeptidase.
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Affiliation(s)
- Zoltán Szeltner
- Institute of Enzymology, Biological Research Center, Hungarian Academy of Sciences, H-1518, P. O. Box 7, Budapest 112, Hungary
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24
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Szeltner Z, Rea D, Renner V, Fulop V, Polgar L. Electrostatic effects and binding determinants in the catalysis of prolyl oligopeptidase. Site specific mutagenesis at the oxyanion binding site. J Biol Chem 2002; 277:42613-22. [PMID: 12202494 DOI: 10.1074/jbc.m208043200] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Prolyl oligopeptidase, a member of a new family of serine peptidases, plays an important role in memory disorders. Earlier x-ray crystallographic investigations indicated that stabilization of the tetrahedral transition state of the reaction involved hydrogen bond formation between the oxyanion of the tetrahedral intermediate and the OH group of Tyr(473). The contribution of the OH group was tested with the Y473F variant using various substrates. The charged succinyl-Gly-Pro-4-nitroanilide was hydrolyzed with a much lower k(cat)/K(m) compared with the neutral benzyloxycarbonyl-G1y-Pro-2-naphthylamide, although the binding modes of the two substrates were similar, as shown by x-ray crystallography. This suggested that electrostatic interactions between Arg(643) and the succinyl group competed with the productive binding mechanism. Unlike most enzyme reactions, catalysis by the wild-type enzyme exhibited positive activation entropy. In contrast, the activation entropy for the Y473F variant was negative, suggesting that the tyrosine OH group is involved in stabilizing both the transition state and the water shell at the active site. Importantly, Tyr(473) is also implicated in the formation of the enzyme-substrate complex. The nonlinear Arrhenius plot suggested a greater significance of the oxyanion binding site at physiological temperature. The results indicated that Tyr(473) was more needed at high pH, at high temperature, and with charged substrates exhibiting "internally competitive inhibition."
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Affiliation(s)
- Zoltan Szeltner
- Institute of Enzymology, Biological Research Center, Hungarian Academy of Sciences, H-1518 Budapest, Hungary
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25
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Fülöp V, Szeltner Z, Renner V, Polgár L. Structures of prolyl oligopeptidase substrate/inhibitor complexes. Use of inhibitor binding for titration of the catalytic histidine residue. J Biol Chem 2001; 276:1262-6. [PMID: 11031266 DOI: 10.1074/jbc.m007003200] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Structure determination of the inactive S554A variant of prolyl oligopeptidase complexed with an octapeptide has shown that substrate binding is restricted to the P4-P2' region. In addition, it has revealed a hydrogen bond network of potential catalytic importance not detected in other serine peptidases. This involves a unique intramolecular hydrogen bond between the P1' amide and P2 carbonyl groups and another between the P2' amide and Nepsilon2 of the catalytic histidine 680 residue. It is argued that both hydrogen bonds promote proton transfer from the imidazolium ion to the leaving group. Another complex formed with the product-like inhibitor benzyloxycarbonyl-glycyl-proline, indicating that the carboxyl group of the inhibitor forms a hydrogen bond with the Nepsilon2 of His(680). Because a protonated histidine makes a stronger interaction with the carboxyl group, it offers a possibility of the determination of the real pK(a) of the catalytic histidine residue. This was found to be 6.25, lower than that of the well studied serine proteases. The new titration method gave a single pK(a) for prolyl oligopeptidase, whose reaction exhibited a complex pH dependence for k(cat)/K(m), and indicated that the observed pK(a) values are apparent. The procedure presented may be applicable for other serine peptidases.
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Affiliation(s)
- V Fülöp
- Department of Biological Sciences, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
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26
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Fülöp V, Szeltner Z, Polgár L. Catalysis of serine oligopeptidases is controlled by a gating filter mechanism. EMBO Rep 2000; 1:277-81. [PMID: 11256612 PMCID: PMC1083722 DOI: 10.1093/embo-reports/kvd048] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Proteases have a variety of strategies for selecting substrates in order to prevent uncontrolled protein degradation. A recent crystal structure determination of prolyl oligopeptidase has suggested a way for substrate selection involving an unclosed seven-bladed beta-propeller domain. We have engineered a disulfide bond between the first and seventh blades of the propeller, which resulted in the loss of enzymatic activity. These results provided direct evidence for a novel strategy of regulation in which oscillating propeller blades act as a gating filter during catalysis, letting small peptide substrates into the active site while excluding large proteins to prevent accidental proteolysis.
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Affiliation(s)
- V Fülöp
- Department of Biological Sciences, University of Warwick, Coventry, UK
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