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Janciauskiene S, Lechowicz U, Pelc M, Olejnicka B, Chorostowska-Wynimko J. Diagnostic and therapeutic value of human serpin family proteins. Biomed Pharmacother 2024; 175:116618. [PMID: 38678961 DOI: 10.1016/j.biopha.2024.116618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 04/15/2024] [Accepted: 04/17/2024] [Indexed: 05/01/2024] Open
Abstract
SERPIN (serine proteinase inhibitors) is an acronym for the superfamily of structurally similar proteins found in animals, plants, bacteria, viruses, and archaea. Over 1500 SERPINs are known in nature, while only 37 SERPINs are found in humans, which participate in inflammation, coagulation, angiogenesis, cell viability, and other pathophysiological processes. Both qualitative or quantitative deficiencies or overexpression and/or abnormal accumulation of SERPIN can lead to diseases commonly referred to as "serpinopathies". Hence, strategies involving SERPIN supplementation, elimination, or correction are utilized and/or under consideration. In this review, we discuss relationships between certain SERPINs and diseases as well as putative strategies for the clinical explorations of SERPINs.
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Affiliation(s)
- Sabina Janciauskiene
- Department of Pulmonary and Infectious Diseases and BREATH German Center for Lung Research (DZL), Hannover Medical School, Hannover, Germany; Department of Genetics and Clinical Immunology, National Institute of Tuberculosis and Lung Diseases, 26 Plocka St, Warsaw 01-138, Poland
| | - Urszula Lechowicz
- Department of Genetics and Clinical Immunology, National Institute of Tuberculosis and Lung Diseases, 26 Plocka St, Warsaw 01-138, Poland
| | - Magdalena Pelc
- Department of Genetics and Clinical Immunology, National Institute of Tuberculosis and Lung Diseases, 26 Plocka St, Warsaw 01-138, Poland
| | - Beata Olejnicka
- Department of Pulmonary and Infectious Diseases and BREATH German Center for Lung Research (DZL), Hannover Medical School, Hannover, Germany
| | - Joanna Chorostowska-Wynimko
- Department of Genetics and Clinical Immunology, National Institute of Tuberculosis and Lung Diseases, 26 Plocka St, Warsaw 01-138, Poland.
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Obaha A, Novinec M. Regulation of Peptidase Activity beyond the Active Site in Human Health and Disease. Int J Mol Sci 2023; 24:17120. [PMID: 38069440 PMCID: PMC10707025 DOI: 10.3390/ijms242317120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 12/01/2023] [Accepted: 12/02/2023] [Indexed: 12/18/2023] Open
Abstract
This comprehensive review addresses the intricate and multifaceted regulation of peptidase activity in human health and disease, providing a comprehensive investigation that extends well beyond the boundaries of the active site. Our review focuses on multiple mechanisms and highlights the important role of exosites, allosteric sites, and processes involved in zymogen activation. These mechanisms play a central role in shaping the complex world of peptidase function and are promising potential targets for the development of innovative drugs and therapeutic interventions. The review also briefly discusses the influence of glycosaminoglycans and non-inhibitory binding proteins on enzyme activities. Understanding their role may be a crucial factor in the development of therapeutic strategies. By elucidating the intricate web of regulatory mechanisms that control peptidase activity, this review deepens our understanding in this field and provides a roadmap for various strategies to influence and modulate peptidase activity.
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Affiliation(s)
| | - Marko Novinec
- Faculty of Chemistry and Chemical Technology, Department of Chemistry and Biochemistry, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia;
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Bhoge PR, Raigawali R, Mardhekar S, Anand S, Kikkeri R. Synergestic interplay of uronic acid and sulfation composition of heparan sulfate on molecular recognition to activity. Carbohydr Res 2023; 532:108919. [PMID: 37557021 DOI: 10.1016/j.carres.2023.108919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 08/02/2023] [Accepted: 08/02/2023] [Indexed: 08/11/2023]
Abstract
Heparan sulfate (HS) is ubiquitous polysaccharide on the surface of all mammalian cells and extracellular matrices. The incredible structural complexity of HS arises from its sulfation patterns and disaccharide compositions, which orchestrate a wide range of biological activities. Researchers have developed elegant synthetic methods to obtain well-defined HS oligosaccharides to understand the structure-activity relationship. These studies revealed that specific sulfation codes and uronic acid variants could synergistically modulate HS-protein interactions (HSPI). Additionally, the conformational flexibility of l-Iduronic acid, a uronic acid unit has emerged as a critical factor in fine-tuning the microenvironment to modulate HSPI. This review delineates how uronic acid composition in HS modulates protein binding affinity, selectivity, and biological activity. Finally, the significance of sulfated homo-oligo uronic acid as heparin mimics in drug development is also discussed.
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Affiliation(s)
- Preeti Ravindra Bhoge
- Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pashan, Pune, 4110008, India
| | - Rakesh Raigawali
- Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pashan, Pune, 4110008, India
| | - Sandhya Mardhekar
- Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pashan, Pune, 4110008, India
| | - Saurabh Anand
- Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pashan, Pune, 4110008, India
| | - Raghavendra Kikkeri
- Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pashan, Pune, 4110008, India.
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4
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Bano S, Khan AB, Fatima S, Rashid Q, Prakash A, Gupta N, Ahmad I, Ansari S, Lynn AM, Abid M, Jairajpuri MA. Mannose 2, 3, 4, 5, 6- O-pentasulfate (MPS): a partial activator of human heparin cofactor II with anticoagulation potential. J Biomol Struct Dyn 2023; 41:3717-3727. [PMID: 35343865 DOI: 10.1080/07391102.2022.2053749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 03/09/2022] [Indexed: 10/18/2022]
Abstract
Thromboembolic diseases are a major cause of mortality in human and the currently available anticoagulants are associated with various drawbacks, therefore the search for anticoagulants that have better safety profile is highly desirable. Compounds that are part of the dietary routine can be modified to possibly increase their anticoagulant potential. We show mannose 2,3,4,5,6-O-pentasulfate (MPS) as a synthetically modified form of mannose that has appreciable anticoagulation properties. An in silico study identified that mannose in sulfated form can bind effectively to the heparin-binding site of antithrombin (ATIII) and heparin cofactor II (HCII). Mannose was sulfated using a simple sulfation strategy-involving triethylamine-sulfur trioxide adduct. HCII and ATIII were purified from human plasma and the binding analysis using fluorometer and isothermal calorimetry showed that MPS binds at a unique site. A thrombin inhibition analysis using the chromogenic substrate showed that MPS partially enhances the activity of HCII. Further an assessment of in vitro blood coagulation assays using human plasma showed that the activated partial thromboplastin time (APTT) and prothrombin time (PT) were prolonged in the presence of MPS. A molecular dynamics simulation analysis of the HCII-MPS complex showed fluctuations in a N-terminal loop and the cofactor binding site of HCII. The results indicate that MPS is a promising lead due to its effect on the in vitro coagulation rate.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Shadabi Bano
- Protein Conformation and Enzymology Lab, Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Abdul Burhan Khan
- Protein Conformation and Enzymology Lab, Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Sana Fatima
- Protein Conformation and Enzymology Lab, Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Qudsia Rashid
- Protein Conformation and Enzymology Lab, Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Amresh Prakash
- School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Neha Gupta
- Protein Conformation and Enzymology Lab, Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Irshad Ahmad
- Protein Conformation and Enzymology Lab, Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Shoyab Ansari
- Protein Conformation and Enzymology Lab, Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Andrew M Lynn
- School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Mohammad Abid
- Medicinal Chemistry Lab, Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Mohamad Aman Jairajpuri
- Protein Conformation and Enzymology Lab, Department of Biosciences, Jamia Millia Islamia, New Delhi, India
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Xu J, Ye W, Yang TT, Yan T, Cai H, Zhou A, Yang Y. DNA accelerates the protease inhibition of a bacterial serpin chloropin. Front Mol Biosci 2023; 10:1157186. [PMID: 37065444 PMCID: PMC10090351 DOI: 10.3389/fmolb.2023.1157186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 03/20/2023] [Indexed: 03/31/2023] Open
Abstract
Serine protease inhibitors (Serpins) are the most widely distributed protease inhibitors in nature and have been identified from all kingdoms of life. Eukaryotic serpins are most abundant with their activities often subject to modulation by cofactors; however, little is known about the regulation of prokaryotic serpins. To address this, here we prepared a recombinant bacteria serpin, termed chloropin, derived from green sulfur bacteria Chlorobium limicola and solved its crystal structure at 2.2 Å resolution. This showed a canonical inhibitory serpin conformation of native chloropin with a surface-exposed reactive loop and a large central beta-sheet. Enzyme activity analysis showed that chloropin could inhibit multiple proteases, such as thrombin and KLK7 with second order inhibition rate constants at 2.5×104 M−1s−1 and 4.5×104 M−1s−1 respectively, consistent with its P1 arginine residue. Heparin could accelerate the thrombin inhibition by ∼17-fold with a bell-shaped dose-dependent curve as seen with heparin-mediated thrombin inhibition by antithrombin. Interestingly, supercoiled DNA could accelerate the inhibition of thrombin by chloropin by 74-fold, while linear DNA accelerated the reaction by 142-fold through a heparin-like template mechanism. In contrast, DNA did not affect the inhibition of thrombin by antithrombin. These results indicate that DNA is likely a natural modulator of chloropin protecting the cell from endogenous or exogenous environmental proteases, and prokaryotic serpins have diverged during evolution to use different surface subsites for activity modulation.
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Affiliation(s)
- Jiawei Xu
- Department of Bioengineering, Zunyi Medical University Zhuhai Campus, Zhuhai, Guangdong, China
| | - Wei Ye
- Department of Preventive Dentistry, The Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ting Ting Yang
- Department of Preventive Dentistry, The Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Teng Yan
- Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Haiyan Cai
- Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- *Correspondence: Haiyan Cai, ; Aiwu Zhou, ; Yufeng Yang,
| | - Aiwu Zhou
- Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- *Correspondence: Haiyan Cai, ; Aiwu Zhou, ; Yufeng Yang,
| | - Yufeng Yang
- Department of Bioengineering, Zunyi Medical University Zhuhai Campus, Zhuhai, Guangdong, China
- *Correspondence: Haiyan Cai, ; Aiwu Zhou, ; Yufeng Yang,
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6
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Hogwood J, Mulloy B, Lever R, Gray E, Page CP. Pharmacology of Heparin and Related Drugs: An Update. Pharmacol Rev 2023; 75:328-379. [PMID: 36792365 DOI: 10.1124/pharmrev.122.000684] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 11/04/2022] [Accepted: 11/08/2022] [Indexed: 02/17/2023] Open
Abstract
Heparin has been used extensively as an antithrombotic and anticoagulant for close to 100 years. This anticoagulant activity is attributed mainly to the pentasaccharide sequence, which potentiates the inhibitory action of antithrombin, a major inhibitor of the coagulation cascade. More recently it has been elucidated that heparin exhibits anti-inflammatory effect via interference of the formation of neutrophil extracellular traps and this may also contribute to heparin's antithrombotic activity. This illustrates that heparin interacts with a broad range of biomolecules, exerting both anticoagulant and nonanticoagulant actions. Since our previous review, there has been an increased interest in these nonanticoagulant effects of heparin, with the beneficial role in patients infected with SARS2-coronavirus a highly topical example. This article provides an update on our previous review with more recent developments and observations made for these novel uses of heparin and an overview of the development status of heparin-based drugs. SIGNIFICANCE STATEMENT: This state-of-the-art review covers recent developments in the use of heparin and heparin-like materials as anticoagulant, now including immunothrombosis observations, and as nonanticoagulant including a role in the treatment of SARS-coronavirus and inflammatory conditions.
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Affiliation(s)
- John Hogwood
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (B.M., E.G., C.P.P.); National Institute for Biological Standards and Control, South Mimms, Hertfordshire, United Kingdom (J.H., E.G.) and School of Pharmacy, University College London, London, United Kingdom (R.L.)
| | - Barbara Mulloy
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (B.M., E.G., C.P.P.); National Institute for Biological Standards and Control, South Mimms, Hertfordshire, United Kingdom (J.H., E.G.) and School of Pharmacy, University College London, London, United Kingdom (R.L.)
| | - Rebeca Lever
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (B.M., E.G., C.P.P.); National Institute for Biological Standards and Control, South Mimms, Hertfordshire, United Kingdom (J.H., E.G.) and School of Pharmacy, University College London, London, United Kingdom (R.L.)
| | - Elaine Gray
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (B.M., E.G., C.P.P.); National Institute for Biological Standards and Control, South Mimms, Hertfordshire, United Kingdom (J.H., E.G.) and School of Pharmacy, University College London, London, United Kingdom (R.L.)
| | - Clive P Page
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (B.M., E.G., C.P.P.); National Institute for Biological Standards and Control, South Mimms, Hertfordshire, United Kingdom (J.H., E.G.) and School of Pharmacy, University College London, London, United Kingdom (R.L.)
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7
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Church FC. Suggestions on leading an academic research laboratory group. Open Life Sci 2022; 17:599-609. [PMID: 35800075 PMCID: PMC9202531 DOI: 10.1515/biol-2022-0061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 02/24/2022] [Accepted: 03/25/2022] [Indexed: 11/15/2022] Open
Abstract
This commentary is about running an academic research laboratory group, including some reflections, memories, and tips on effectively managing such a group of scientists focused on one’s research. The author’s academic career has spanned from 1982 to 2022, including postdoctoral research associate through the rank of professor with tenure. Currently, the author is in the final year of 3 years of phased retirement. One must be willing to work hard at running a research laboratory. Also, stay focused on funding the laboratory tasks and publishing one’s work. Recruit the best people possible with advice from the collective laboratory group. Laboratory group members felt more like they were a part of a collective family than simply employees; however, what works best for the researcher is what matters. Several other points to discuss will include managing university roles, recruiting laboratory personnel, getting recognition, dealing with intellectual property rights, and publishing work. In closing, there are many more positives than negatives to leading a research laboratory group. Finally, one cannot replace the unforgettable memories and the legacy of a research laboratory group.
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Affiliation(s)
- Frank C. Church
- Department of Pathology and Laboratory Medicine, The University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
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Grover SP, Mackman N. Anticoagulant SERPINs: Endogenous Regulators of Hemostasis and Thrombosis. Front Cardiovasc Med 2022; 9:878199. [PMID: 35592395 PMCID: PMC9110684 DOI: 10.3389/fcvm.2022.878199] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 03/29/2022] [Indexed: 12/17/2022] Open
Abstract
Appropriate activation of coagulation requires a balance between procoagulant and anticoagulant proteins in blood. Loss in this balance leads to hemorrhage and thrombosis. A number of endogenous anticoagulant proteins, such as antithrombin and heparin cofactor II, are members of the serine protease inhibitor (SERPIN) family. These SERPIN anticoagulants function by forming irreversible inhibitory complexes with target coagulation proteases. Mutations in SERPIN family members, such as antithrombin, can cause hereditary thrombophilias. In addition, low plasma levels of SERPINs have been associated with an increased risk of thrombosis. Here, we review the biological activities of the different anticoagulant SERPINs. We further consider the clinical consequences of SERPIN deficiencies and insights gained from preclinical disease models. Finally, we discuss the potential utility of engineered SERPINs as novel therapies for the treatment of thrombotic pathologies.
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Exosite Binding in Thrombin: A Global Structural/Dynamic Overview of Complexes with Aptamers and Other Ligands. Int J Mol Sci 2021; 22:ijms221910803. [PMID: 34639143 PMCID: PMC8509272 DOI: 10.3390/ijms221910803] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 09/24/2021] [Accepted: 10/01/2021] [Indexed: 12/13/2022] Open
Abstract
Thrombin is the key enzyme of the entire hemostatic process since it is able to exert both procoagulant and anticoagulant functions; therefore, it represents an attractive target for the developments of biomolecules with therapeutic potential. Thrombin can perform its many functional activities because of its ability to recognize a wide variety of substrates, inhibitors, and cofactors. These molecules frequently are bound to positively charged regions on the surface of protein called exosites. In this review, we carried out extensive analyses of the structural determinants of thrombin partnerships by surveying literature data as well as the structural content of the Protein Data Bank (PDB). In particular, we used the information collected on functional, natural, and synthetic molecular ligands to define the anatomy of the exosites and to quantify the interface area between thrombin and exosite ligands. In this framework, we reviewed in detail the specificity of thrombin binding to aptamers, a class of compounds with intriguing pharmaceutical properties. Although these compounds anchor to protein using conservative patterns on its surface, the present analysis highlights some interesting peculiarities. Moreover, the impact of thrombin binding aptamers in the elucidation of the cross-talk between the two distant exosites is illustrated. Collectively, the data and the work here reviewed may provide insights into the design of novel thrombin inhibitors.
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10
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The 3- O-sulfation of heparan sulfate modulates protein binding and lyase degradation. Proc Natl Acad Sci U S A 2021; 118:2012935118. [PMID: 33441484 DOI: 10.1073/pnas.2012935118] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Humans express seven heparan sulfate (HS) 3-O-sulfotransferases that differ in substrate specificity and tissue expression. Although genetic studies have indicated that 3-O-sulfated HS modulates many biological processes, ligand requirements for proteins engaging with HS modified by 3-O-sulfate (3-OS) have been difficult to determine. In particular, the context in which the 3-OS group needs to be presented for binding is largely unknown. We describe herein a modular synthetic approach that can provide structurally diverse HS oligosaccharides with and without 3-OS. The methodology was employed to prepare 27 hexasaccharides that were printed as a glycan microarray to examine ligand requirements of a wide range of HS-binding proteins. The binding selectivity of antithrombin-III (AT-III) compared well with anti-Factor Xa activity supporting robustness of the array technology. Many of the other examined HS-binding proteins required an IdoA2S-GlcNS3S6S sequon for binding but exhibited variable dependence for the 2-OS and 6-OS moieties, and a GlcA or IdoA2S residue neighboring the central GlcNS3S. The HS oligosaccharides were also examined as inhibitors of cell entry by herpes simplex virus type 1, which, surprisingly, showed a lack of dependence of 3-OS, indicating that, instead of glycoprotein D (gD), they competitively bind to gB and gC. The compounds were also used to examine substrate specificities of heparin lyases, which are enzymes used for depolymerization of HS/heparin for sequence determination and production of therapeutic heparins. It was found that cleavage by lyase II is influenced by 3-OS, while digestion by lyase I is only affected by 2-OS. Lyase III exhibited sensitivity to both 3-OS and 2-OS.
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Izaguirre G, Swanson R, Roth R, Gettins PGW, Olson ST. Paramount Importance of Core Conformational Changes for Heparin Allosteric Activation of Antithrombin. Biochemistry 2021; 60:1201-1213. [PMID: 33822598 PMCID: PMC10921935 DOI: 10.1021/acs.biochem.1c00128] [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] [Indexed: 11/28/2022]
Abstract
Antithrombin is unique among serpin family protein protease inhibitors with respect to the major reactive center loop (RCL) and core conformational changes that mediate allosteric activation of its anticoagulant function by heparin. A critical role for expulsion of the RCL hinge from a native stabilizing interaction with the hydrophobic core in the activation mechanism has been proposed from reports that antithrombin variants that block this change through engineered disulfide bonds block activation. However, the sufficiency of core conformational changes for activation without expulsion of the RCL from the core is suggested by variants that are activated without the need for heparin and retain the native RCL-core interaction. To resolve these apparently conflicting findings, we engineered variants in which disulfides designed to block the RCL conformational change were combined with constitutively activating mutations. Our findings demonstrate that while a reversible constitutive activation can be engineered in variants that retain the native RCL-core interaction, engineered disulfides that lock the RCL native conformation can also block heparin allosteric activation. Such findings support a three-state allosteric activation model in which constitutive activating mutations stabilize an intermediate-activated state wherein core conformational changes and a major activation have occurred without the release of the RCL from the core but with a necessary repositioning of the RCL to allow productive engagement with an exosite. Rigid disulfide bonds that lock the RCL native conformation block heparin activation by preventing both RCL repositioning in the intermediate-activated state and the release of the RCL from the core in the fully activated state.
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12
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Serpins in cartilage and osteoarthritis: what do we know? Biochem Soc Trans 2021; 49:1013-1026. [PMID: 33843993 PMCID: PMC8106492 DOI: 10.1042/bst20201231] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 02/17/2021] [Accepted: 03/04/2021] [Indexed: 12/13/2022]
Abstract
Serpins (serine proteinase inhibitors) are an ancient superfamily of structurally similar proteins, the majority of which use an elegant suicide inhibition mechanism to target serine proteinases. Despite likely evolving from a single common ancestor, the 36 human serpins have established roles regulating diverse biological processes, such as blood coagulation, embryonic development and extracellular matrix (ECM) turnover. Genetic mutations in serpin genes underpin a host of monogenic disorders — collectively termed the ‘serpinopathies’ — but serpin dysregulation has also been shown to drive pathological mechanisms in many common diseases. Osteoarthritis is a degenerative joint disorder, characterised by the progressive destruction of articular cartilage. This breakdown of the cartilage is driven by the metalloproteinases, and it has long been established that an imbalance of metalloproteinases to their inhibitors is of critical importance. More recently, a role for serine proteinases in cartilage destruction is emerging; including the activation of latent matrix metalloproteinases and cell-surface receptors, or direct proteolysis of the ECM. Serpins likely regulate these processes, as well as having roles beyond serine proteinase inhibition. Indeed, serpins are routinely observed to be highly modulated in osteoarthritic tissues and fluids by ‘omic analysis, but despite this, they are largely ignored. Confusing nomenclature and an underappreciation for the role of serine proteinases in osteoarthritis (OA) being the likely causes. In this narrative review, serpin structure, biochemistry and nomenclature are introduced, and for the first time, their putative importance in maintaining joint tissues — as well as their dysregulation in OA — are explored.
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13
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Oral administration of dermatan sulphate reduces venous thrombus formation in vivo: potential use as a formulation for venous thromboembolism. Inflammopharmacology 2020; 29:525-535. [PMID: 33230702 DOI: 10.1007/s10787-020-00771-x] [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: 06/24/2020] [Accepted: 10/25/2020] [Indexed: 10/22/2022]
Abstract
Dermatan sulphate (DS) is a sulphated polysaccharide that displays complexity in constituent sulphated disaccharides and interacts with proteins and signalling molecules to modulate numerous biological processes, including inhibition of the coagulation cascade and regulation of blood clotting and fibrinolysis. This study shows the antithrombotic and anticoagulant effects of DS prepared from bovine collagen waste liquor following oral and intravenous administrations in a deep vein thrombosis (DVT) rabbit model. In vitro, the prothrombin time, activated partial thromboplastin time, and thrombin citrated plasma clotting assays revealed that bovine DS had strong antithrombotic and anticoagulant effects comparable to low-molecular-weight heparin [Clexane® (enoxaparin sodium)]. In a DVT rabbit model, animals received intravenous and oral administrations of bovine DS and Clexane® providing further evidence that both agents had strong antithrombotic and anticoagulant effects by significantly reducing or preventing clot formation. Thromboelastography (TEG) assays revealed further that both bovine DS and Clexane® substantially prolonged the clotting time of recalcified citrated whole blood, but only bovine DS could retain clot strength suggesting that bovine DS had less effect on platelet-fibrin interactions. In conclusion, this is the first report that oral administration of DS from bovine collagen waste liquor reduces experimental venous thrombus formation warranting further research into bovine DS as an oral antithrombotic therapeutic.
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14
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Bano S, Fatima S, Ahamad S, Ansari S, Gupta D, Tabish M, Rehman SU, Jairajpuri MA. Identification and characterization of a novel isoform of heparin cofactor II in human liver. IUBMB Life 2020; 72:2180-2193. [PMID: 32827448 DOI: 10.1002/iub.2361] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 07/05/2020] [Accepted: 07/07/2020] [Indexed: 11/07/2022]
Abstract
Heparin cofactor II (HCII) is predominantly expressed in the liver and inhibits thrombin in blood plasma to influence the blood coagulation cascade. Its deficiency is associated with arterial thrombosis. Its cleavage by neutrophil elastase produces fragment that helps in neutrophil chemotaxis in the acute inflammatory response in human. In the present study, we have identified a novel alternatively spliced transcript of the HCII gene in human liver. This novel transcript includes an additional novel region in continuation with exon 3 called exon 3b. Exon 3b acts like an alternate last exon, and hence its inclusion in the transcript due to alternative splicing removes exon 4 and encodes for a different C-terminal region to give a novel protein, HCII-N. MD simulations of HCII-N and three-dimensional structure showed a unique 51 amino acid sequence at the C-terminal having unique RCL-like structure. The HCII-N protein purified from bacterial culture showed a protein migrating at lower molecular weight (MW 55 kDa) as compared to native HCII (MW 66 kDa). A fluorescence-based analysis revealed a more compact structure of HCII-N that was in a more hydrophilic environment. The HCII-N protein, however, showed no inhibitory activity against thrombin. Due to large conformational variation observed in comparison with native HCII, HCII-N may have alternate protease specificity or a non-inhibitory role. Western blot of HCII purified from large plasma volume showed the presence of a low MW 59 kDa band with no thrombin activity. This study provides the first evidence of alternatively spliced novel isoform of the HCII gene.
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Affiliation(s)
- Shadabi Bano
- Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Sana Fatima
- Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Shahzaib Ahamad
- Translational Bioinformatics Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Shoyab Ansari
- Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Dinesh Gupta
- Translational Bioinformatics Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Mohammad Tabish
- Department of Biochemistry, Faculty of Life Sciences, Aligarh M. University, Aligarh, India
| | - Sayeed Ur Rehman
- Department of Biochemistry, School of Chemical and Life Sciences, Jamia Hamdard, New Delhi, India
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Derbalah A, Duffull S, Newall F, Moynihan K, Al-Sallami H. Revisiting the Pharmacology of Unfractionated Heparin. Clin Pharmacokinet 2020; 58:1015-1028. [PMID: 30850987 DOI: 10.1007/s40262-019-00751-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Unfractionated heparin (UFH) is a commonly used anticoagulant therapy for the acute treatment and prevention of thrombosis. Its short duration of action, reversibility of effect by protamine sulfate, and extensive clinical experience are some of the advantages that support its use. However, the choice of dose and dosing regimen of UFH remains challenging for several reasons. First, UFH has a narrow therapeutic window and wide variability in the dose-response relationship. Second, its pharmacodynamic (PD) properties are difficult to characterise owing to the complex multidimensional mechanisms of interaction with the haemostatic system. Third, the complex heterogeneous chemical composition of UFH precludes precise characterisation of its pharmacokinetic (PK) properties. This review provides a comprehensive mechanistic approach to the interaction of UFH with the haemostatic system. The effect of chemical structure on its PK and PD properties is quantitatively described, and a framework for characterisation of the dose-response relationship of UFH for the purpose of dose optimisation is proposed.
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Affiliation(s)
| | - Stephen Duffull
- School of Pharmacy, University of Otago, Dunedin, New Zealand
| | - Fiona Newall
- Department of Nursing, The University of Melbourne, Parkville, VIC, Australia.,Department of Paediatrics, The Royal Children's Hospital, The University of Melbourne, Parkville, VIC, Australia
| | - Katie Moynihan
- Department of Cardiology, Boston Children's Hospital, Boston, MA, USA.,Department of Paediatrics, Harvard Medical School, Boston, MA, USA
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Ma L, Wu J, Zheng Y, Shu Z, Wei Z, Sun Y, Carrell RW, Zhou A. Heparin Blocks the Inhibition of Tissue Kallikrein 1 by Kallistatin through Electrostatic Repulsion. Biomolecules 2020; 10:E828. [PMID: 32481593 PMCID: PMC7356578 DOI: 10.3390/biom10060828] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 05/26/2020] [Accepted: 05/26/2020] [Indexed: 11/16/2022] Open
Abstract
Kallistatin, also known as SERPINA4, has been implicated in the regulation of blood pressure and angiogenesis, due to its specific inhibition of tissue kallikrein 1 (KLK1) and/or by its heparin binding ability. The binding of heparin on kallistatin has been shown to block the inhibition of KLK1 by kallistatin but the detailed molecular mechanism underlying this blockade is unclear. Here we solved the crystal structures of human kallistatin and its complex with heparin at 1.9 and 1.8 Å resolution, respectively. The structures show that kallistatin has a conserved serpin fold and undergoes typical stressed-to-relaxed conformational changes upon reactive loop cleavage. Structural analysis and mutagenesis studies show that the heparin binding site of kallistatin is located on a surface with positive electrostatic potential near a unique protruded 310 helix between helix H and strand 2 of β-sheet C. Heparin binding on this site would prevent KLK1 from docking onto kallistatin due to the electrostatic repulsion between heparin and the negatively charged surface of KLK1, thus blocking the inhibition of KLK1 by kallistatin. Replacement of the acidic exosite 1 residues of KLK1 with basic amino acids as in thrombin resulted in accelerated inhibition. Taken together, these data indicate that heparin controls the specificity of kallistatin, such that kinin generation by KLK1 within the microcirculation will be locally protected by the binding of kallistatin to the heparin-like glycosaminoglycans of the endothelium.
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Affiliation(s)
- Lina Ma
- Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China; (L.M.); (J.W.); (Z.S.); (Z.W.)
| | - Jiawei Wu
- Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China; (L.M.); (J.W.); (Z.S.); (Z.W.)
| | - Ying Zheng
- Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China; (L.M.); (J.W.); (Z.S.); (Z.W.)
| | - Zimei Shu
- Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China; (L.M.); (J.W.); (Z.S.); (Z.W.)
| | - Zhenquan Wei
- Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China; (L.M.); (J.W.); (Z.S.); (Z.W.)
| | - Yinbiao Sun
- Randall Division of Cell & Molecular Biophysics, Faculty of Life Sciences & Medicine, King’s College London, New Hunt’s House, Guy’s Campus, London SE1 1UL, UK;
| | - Robin W. Carrell
- Department of Haematology, University of Cambridge, Cambridge CB2 0XY, UK;
| | - Aiwu Zhou
- Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China; (L.M.); (J.W.); (Z.S.); (Z.W.)
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Mehta AY, Heimburg-Molinaro J, Cummings RD, Goth CK. Emerging patterns of tyrosine sulfation and O-glycosylation cross-talk and co-localization. Curr Opin Struct Biol 2020; 62:102-111. [PMID: 31927217 DOI: 10.1016/j.sbi.2019.12.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 11/26/2019] [Accepted: 12/02/2019] [Indexed: 12/31/2022]
Affiliation(s)
- Akul Y Mehta
- Department of Surgery, Beth Israel Deaconess Medical Center, National Center for Functional Glycomics, Harvard Medical School, Boston, MA, 02215, USA
| | - Jamie Heimburg-Molinaro
- Department of Surgery, Beth Israel Deaconess Medical Center, National Center for Functional Glycomics, Harvard Medical School, Boston, MA, 02215, USA
| | - Richard D Cummings
- Department of Surgery, Beth Israel Deaconess Medical Center, National Center for Functional Glycomics, Harvard Medical School, Boston, MA, 02215, USA
| | - Christoffer K Goth
- Department of Surgery, Beth Israel Deaconess Medical Center, National Center for Functional Glycomics, Harvard Medical School, Boston, MA, 02215, USA
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Pathak M, Manna R, Li C, Kaira BG, Hamad BK, Belviso BD, Bonturi CR, Dreveny I, Fischer PM, Dekker LV, Oliva MLV, Emsley J. Crystal structures of the recombinant β-factor XIIa protease with bound Thr-Arg and Pro-Arg substrate mimetics. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2019; 75:578-591. [DOI: 10.1107/s2059798319006910] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Accepted: 05/13/2019] [Indexed: 11/10/2022]
Abstract
Coagulation factor XII (FXII) is a key initiator of the contact pathway, which contributes to inflammatory pathways. FXII circulates as a zymogen, which when auto-activated forms factor XIIa (FXIIa). Here, the production of the recombinant FXIIa protease domain (βFXIIaHis) with yields of ∼1–2 mg per litre of insect-cell culture is reported. A second construct utilized an N-terminal maltose-binding protein (MBP) fusion (MBP-βFXIIaHis). Crystal structures were determined of MBP-βFXIIaHisin complex with the inhibitor D-Phe-Pro-Arg chloromethyl ketone (PPACK) and of βFXIIaHisin isolation. The βFXIIaHisstructure revealed that the S2 and S1 pockets were occupied by Thr and Arg residues, respectively, from an adjacent molecule in the crystal. The Thr-Arg sequence mimics the P2–P1 FXIIa cleavage-site residues present in the natural substrates prekallikrein and FXII, and Pro-Arg (from PPACK) mimics the factor XI cleavage site. A comparison of the βFXIIaHisstructure with the available crystal structure of the zymogen-like FXII protease revealed large conformational changes centred around the S1 pocket and an alternate conformation for the 99-loop, Tyr99 and the S2 pocket. Further comparison with activated protease structures of factors IXa and Xa, which also have the Tyr99 residue, reveals that a more open form of the S2 pocket only occurs in the presence of a substrate mimetic. The FXIIa inhibitors EcTI and infestin-4 have Pro-Arg and Phe-Arg P2–P1 sequences, respectively, and the interactions that these inhibitors make with βFXIIa are also described. These structural studies of βFXIIa provide insight into substrate and inhibitor recognition and establish a scaffold for the structure-guided drug design of novel antithrombotic and anti-inflammatory agents.
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Dou H, Song A, Jia S, Zhang L. Heparinoids Danaparoid and Sulodexide as clinically used drugs. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2019; 163:55-74. [DOI: 10.1016/bs.pmbts.2019.02.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Roudnický P, Vorel J, Ilgová J, Benovics M, Norek A, Jedličková L, Mikeš L, Potěšil D, Zdráhal Z, Dvořák J, Gelnar M, Kašný M. Identification and partial characterization of a novel serpin from Eudiplozoon nipponicum (Monogenea, Polyopisthocotylea). ACTA ACUST UNITED AC 2018; 25:61. [PMID: 30516130 PMCID: PMC6280883 DOI: 10.1051/parasite/2018062] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 11/16/2018] [Indexed: 12/14/2022]
Abstract
Background: Serpins are a superfamily of serine peptidase inhibitors that participate in the regulation of many physiological and cell peptidase-mediated processes in all organisms (e.g. in blood clotting, complement activation, fibrinolysis, inflammation, and programmed cell death). It was postulated that in the blood-feeding members of the monogenean family Diplozoidae, serpins could play an important role in the prevention of thrombus formation, activation of complement, inflammation in the host, and/or in the endogenous regulation of protein degradation. Results: In silico analysis showed that the DNA and primary protein structures of serpin from Eudiplozoon nipponicum (EnSerp1) are similar to other members of the serpin superfamily. The inhibitory potential of EnSerp1 on four physiologically-relevant serine peptidases (trypsin, factor Xa, kallikrein, and plasmin) was demonstrated and its presence in the worm’s excretory-secretory products (ESPs) was confirmed. Conclusion: EnSerp1 influences the activity of peptidases that play a role in blood coagulation, fibrinolysis, and complement activation. This inhibitory potential, together with the serpin’s presence in ESPs, suggests that it is likely involved in host-parasite interactions and could be one of the molecules involved in the control of feeding and prevention of inflammatory responses.
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Affiliation(s)
- Pavel Roudnický
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
| | - Jiří Vorel
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
| | - Jana Ilgová
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
| | - Michal Benovics
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
| | - Adam Norek
- Veterinary Research Institute, Hudcova 296/70, 62100 Brno, Czech Republic
| | - Lucie Jedličková
- Department of Parasitology, Faculty of Science, Charles University, Viničná 7, 12844 Prague 2, Czech Republic
| | - Libor Mikeš
- Department of Parasitology, Faculty of Science, Charles University, Viničná 7, 12844 Prague 2, Czech Republic
| | - David Potěšil
- Central European Institute of Technology, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
| | - Zbyněk Zdráhal
- Central European Institute of Technology, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic - National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
| | - Jan Dvořák
- School of Biological Sciences, Medical Biology Centre, Queen's University Belfast, 97 Lisburn Road, Belfast BT9 7BL, United Kingdom - Department of Zoology and Fisheries, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences in Prague, Kamýcká 129, 16521 Prague, Czech Republic
| | - Milan Gelnar
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
| | - Martin Kašný
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic - Department of Parasitology, Faculty of Science, Charles University, Viničná 7, 12844 Prague 2, Czech Republic
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Modulating the degree of fucosylation of fucosylated chondroitin sulfate enhances heparin cofactor II-dependent thrombin inhibition. Eur J Med Chem 2018; 154:133-143. [PMID: 29787913 DOI: 10.1016/j.ejmech.2018.05.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 04/30/2018] [Accepted: 05/15/2018] [Indexed: 12/24/2022]
Abstract
Fucosylated chondroitin sulfate (FCS), an unusual glycosaminoglycan with fucose side chains, is a promising anticoagulant agent. To assess the effect of its structure on anticoagulant activity, its derivatives with various degrees of fucosylation (DF), molecular weights (Mw) and sulfation patterns were prepared and characterized. Biological tests showed that their APTT (activated partial thromboplastin time) prolonging activity and intrinsic factor Xase complex (factor IXa-VIIIa-Ca2+-PL complex) inhibitory activity were both reduced in FCS derivatives with lower Mw and DF. However, FCSs with DF at least 16% resulted in greater heparin cofactor II (HCII)-dependent thrombin inhibitory activity in response to decreasing DF, and these activities did not depend on Mw (Mw > 5.2 kDa). Solution competition binding assay further suggested that modulating the DF of FCS derivatives might enhance inhibition of thrombin by activating HCII. These findings imply that FCS derivatives with suitable chain length and DF value may be novel anticoagulants by activating HCII.
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Liu Y, Fu J, Pan W, Xue Q, Liu X, Zhang A. Inhibition of thrombin by functionalized C 60 nanoparticles revealed via in vitro assays and in silico studies. J Environ Sci (China) 2018; 63:285-295. [PMID: 29406112 DOI: 10.1016/j.jes.2017.08.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 08/09/2017] [Accepted: 08/21/2017] [Indexed: 06/07/2023]
Abstract
The studies on the human toxicity of nanoparticles (NPs) are far behind the rapid development of engineered functionalized NPs. Fullerene has been widely used as drug carrier skeleton due to its reported low risk. However, different from other kinds of NPs, fullerene-based NPs (C60 NPs) have been found to have an anticoagulation effect, although the potential target is still unknown. In the study, both experimental and computational methods were adopted to gain mechanistic insight into the modulation of thrombin activity by nine kinds of C60 NPs with diverse surface chemistry properties. In vitro enzyme activity assays showed that all tested surface-modified C60 NPs exhibited thrombin inhibition ability. Kinetic studies coupled with competitive testing using 3 known inhibitors indicated that six of the C60 NPs, of greater hydrophobicity and hydrogen bond (HB) donor acidity or acceptor basicity, acted as competitive inhibitors of thrombin by directly interacting with the active site of thrombin. A simple quantitative nanostructure-activity relationship model relating the surface substituent properties to the inhibition potential was then established for the six competitive inhibitors. Molecular docking analysis revealed that the intermolecular HB interactions were important for the specific binding of C60 NPs to the active site canyon, while the additional stability provided by the surface groups through van der Waals interaction also play a key role in the thrombin binding affinity of the NPs. Our results suggest that thrombin is a possible target of the surface-functionalized C60 NPs relevant to their anticoagulation effect.
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Affiliation(s)
- Yanyan Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China.
| | - Jianjie Fu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Wenxiao Pan
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Qiao Xue
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Xian Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Aiqian Zhang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China; Institute of Environment and Health, Jianghan University, Wuhan 430056, China.
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Heparinase Is Essential for Pseudomonas aeruginosa Virulence during Thermal Injury and Infection. Infect Immun 2017; 86:IAI.00755-17. [PMID: 29061710 DOI: 10.1128/iai.00755-17] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 10/18/2017] [Indexed: 01/07/2023] Open
Abstract
The opportunistic pathogen Pseudomonas aeruginosa is a major cause of sepsis in severely burned patients. If it is not eradicated from the wound, it translocates to the bloodstream, causing sepsis, multiorgan failure, and death. We recently described the P. aeruginosa heparinase-encoding gene, hepP, whose expression was significantly enhanced when P. aeruginosa strain UCBPP_PA14 (PA14) was grown in whole blood from severely burned patients. Further analysis demonstrated that hepP contributed to the in vivo virulence of PA14 in the Caenorhabditis elegans model. In this study, we utilized the murine model of thermal injury to examine the contribution of hepP to the pathogenesis of P. aeruginosa during burn wound infection. Mutation of hepP reduced the rate of mortality from 100% for mice infected with PA14 to 7% for mice infected with PA14::hepP While comparable numbers of PA14 and PA14::hepP bacteria were recovered from infected skin, only PA14 was recovered from the livers and spleens of infected mice. Despite its inability to spread systemically, PA14::hepP formed perivascular cuffs around the blood vessels within the skin of the thermally injured/infected mice. Intraperitoneal inoculation of the thermally injured mice, bypassing the need for translocation, produced similar results. The rate of mortality for mice infected with PA14::hepP was 0%, whereas it was 66% for mice infected with PA14. As before, only PA14 was recovered from the livers and spleens of infected mice. These results suggest that hepP plays a crucial role in the pathogenesis of PA14 during burn wound infection, most likely by contributing to PA14 survival in the bloodstream of the thermally injured mouse during sepsis.
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Nagahashi K, Takano K, Suzuki-Inoue K, Kanayama N, Umemura K, Urano T, Iwaki T. Mutation in a highly conserved glycine residue in strand 5B of plasminogen activator inhibitor 1 causes polymerisation. Thromb Haemost 2017; 117:860-869. [DOI: 10.1160/th16-07-0572] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 01/27/2017] [Indexed: 11/05/2022]
Abstract
SummarySerpinopathy is characterised as abnormal accumulation of serine protease inhibitors (SERPINs) in cells and results in clinical symptoms owing to lack of SERPIN function or excessive accumulation of abnormal SERPIN. We recently identified a patient with functional deficiency of plasminogen activator inhibitor-1 (PAI-1), a member of the SERPIN superfamily. The patient exhibited life-threatening bleeding tendencies, which have also been observed in patients with a complete deficiency in PAI-1. Sequence analysis revealed a homozygous singlenucleotide substitution from guanine to cytosine at exon 9, which changed amino acid residue 397 from glycine to arginine (c.1189G>C; p.Gly397Arg). This glycine was located in strand 5B and was well conserved in other serpins. The mutant PAI-1 was polymerised in the cells, interfering with PAI-1 secretion. The corresponding mutations in SERPINC1 (anti-thrombin III) at position 456 (Gly456Arg) and SERPINI1 (neuroserpin) at position 392 (Gly392Glu) caused an anti-thrombin deficiency and severe dementia due to intracellular retention of the polymers. Glycine is the smallest amino acid, and these mutated amino acids were larger and charged. To determine which factors were important, further mutagenesis of PAI-1 was performed. Although the G397A, C, I, L, S, T, and V were secreted, the G397D, E, F, H, K, M, N, P, Q, W, and Y were not secreted. The results revealed that the size was likely triggered by the polymerisation of SEPRINs at this position. Structural analyses of this mutated PAI-1 would be useful to develop a novel PAI-1 inhibitor, which may be applicable in the context of several pathological states.
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Xiao J, Salsbury FR. Molecular dynamics simulations of aptamer-binding reveal generalized allostery in thrombin. J Biomol Struct Dyn 2017; 35:3354-3369. [PMID: 27794633 PMCID: PMC6876308 DOI: 10.1080/07391102.2016.1254682] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 10/21/2016] [Indexed: 01/11/2023]
Abstract
Thrombin is an attractive target for antithrombotic therapy due to its central role in thrombosis and hemostasis as well as its role in inducing tumor growth, metastasis, and tumor invasion. The thrombin-binding DNA aptamer (TBA), is under investigation for anticoagulant drugs. Although aptamer binding experiments have been revealed various effects on thrombin's enzymatic activities, the detailed picture of the thrombin's allostery from TBA binding is still unclear. To investigate thrombin's response to the aptamer-binding at the molecular level, we compare the mechanical properties and free energy landscapes of the free and aptamer-bound thrombin using microsecond-scale all-atom GPU-based molecular dynamics simulations. Our calculations on residue fluctuations and coupling illustrate the allosteric effects of aptamer-binding at the atomic level, highlighting the exosite II, 60s, γ and the sodium loops, and the alpha helix region in the light chains involved in the allosteric changes. This level of details clarifies the mechanisms of previous experimentally demonstrated phenomena, and provides a prediction of the reduced autolysis rate after aptamer-binding. The shifts in thrombin's ensemble of conformations and free energy surfaces after aptamer-binding demonstrate that the presence of bound-aptamer restricts the conformational freedom of thrombin suggesting that conformational selection, i.e. generalized allostery, is the dominant mechanism of thrombin-aptamer binding. The profound perturbation on thrombin's mechanical and thermodynamic properties due to the aptamer-binding, which was revealed comprehensively as a generalized allostery in this work, may be exploited in further drug discovery and development.
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Affiliation(s)
- Jiajie Xiao
- Department of Physics, Wake Forest University, Winston-Salem, NC, USA
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Whole-exome sequencing in evaluation of patients with venous thromboembolism. Blood Adv 2017; 1:1224-1237. [PMID: 29296762 DOI: 10.1182/bloodadvances.2017005249] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 05/26/2017] [Indexed: 01/05/2023] Open
Abstract
Genetics play a significant role in venous thromboembolism (VTE), yet current clinical laboratory-based testing identifies a known heritable thrombophilia (factor V Leiden, prothrombin gene mutation G20210A, or a deficiency of protein C, protein S, or antithrombin) in only a minority of VTE patients. We hypothesized that a substantial number of VTE patients could have lesser-known thrombophilia mutations. To test this hypothesis, we performed whole-exome sequencing (WES) in 64 patients with VTE, focusing our analysis on a novel 55-gene extended thrombophilia panel that we compiled. Our extended thrombophilia panel identified a probable disease-causing genetic variant or variant of unknown significance in 39 of 64 study patients (60.9%), compared with 6 of 237 control patients without VTE (2.5%) (P < .0001). Clinical laboratory-based thrombophilia testing identified a heritable thrombophilia in only 14 of 54 study patients (25.9%). The majority of WES variants were either associated with thrombosis based on prior reports in the literature or predicted to affect protein structure based on protein modeling performed as part of this study. Variants were found in major thrombophilia genes, various SERPIN genes, and highly conserved areas of other genes with established or potential roles in coagulation or fibrinolysis. Ten patients (15.6%) had >1 variant. Sanger sequencing performed in family members of 4 study patients with and without VTE showed generally concordant results with thrombotic history. WES and extended thrombophilia testing are promising tools for improving our understanding of VTE pathogenesis and identifying inherited thrombophilias.
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Inhibitory serpins. New insights into their folding, polymerization, regulation and clearance. Biochem J 2017; 473:2273-93. [PMID: 27470592 DOI: 10.1042/bcj20160014] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 03/31/2016] [Indexed: 12/20/2022]
Abstract
Serpins are a widely distributed family of high molecular mass protein proteinase inhibitors that can inhibit both serine and cysteine proteinases by a remarkable mechanism-based kinetic trapping of an acyl or thioacyl enzyme intermediate that involves massive conformational transformation. The trapping is based on distortion of the proteinase in the complex, with energy derived from the unique metastability of the active serpin. Serpins are the favoured inhibitors for regulation of proteinases in complex proteolytic cascades, such as are involved in blood coagulation, fibrinolysis and complement activation, by virtue of the ability to modulate their specificity and reactivity. Given their prominence as inhibitors, much work has been carried out to understand not only the mechanism of inhibition, but how it is fine-tuned, both spatially and temporally. The metastability of the active state raises the question of how serpins fold, whereas the misfolding of some serpin variants that leads to polymerization and pathologies of liver disease, emphysema and dementia makes it clinically important to understand how such polymerization might occur. Finally, since binding of serpins and their proteinase complexes, particularly plasminogen activator inhibitor-1 (PAI-1), to the clearance and signalling receptor LRP1 (low density lipoprotein receptor-related protein 1), may affect pathways linked to cell migration, angiogenesis, and tumour progression, it is important to understand the nature and specificity of binding. The current state of understanding of these areas is addressed here.
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Sankarayanarayanan NV, Strebel TR, Boothello RS, Sheerin K, Raghuraman A, Sallas F, Mosier PD, Watermeyer ND, Oscarson S, Desai UR. A Hexasaccharide Containing Rare 2-O-Sulfate-Glucuronic Acid Residues Selectively Activates Heparin Cofactor II. Angew Chem Int Ed Engl 2017; 56:2312-2317. [PMID: 28124818 PMCID: PMC5347859 DOI: 10.1002/anie.201609541] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 01/10/2017] [Indexed: 11/12/2022]
Abstract
Glycosaminoglycan (GAG) sequences that selectively target heparin cofactor II (HCII), a key serpin present in human plasma, remain unknown. Using a computational strategy on a library of 46 656 heparan sulfate hexasaccharides we identified a rare sequence consisting of consecutive glucuronic acid 2-O-sulfate residues as selectively targeting HCII. This and four other unique hexasaccharides were chemically synthesized. The designed sequence was found to activate HCII ca. 250-fold, while leaving aside antithrombin, a closely related serpin, essentially unactivated. This group of rare designed hexasaccharides will help understand HCII function. More importantly, our results show for the first time that rigorous use of computational techniques can lead to discovery of unique GAG sequences that can selectively target GAG-binding protein(s), which may lead to chemical biology or drug discovery tools.
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Affiliation(s)
- Nehru Viji Sankarayanarayanan
- Department of Medicinal Chemistry and Institute of Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA, USA
| | - Tamara R Strebel
- Centre for Synthesis and Chemical Biology, University College of Dublin, Belfield, Dublin, 4, Ireland
| | - Rio S Boothello
- Department of Medicinal Chemistry and Institute of Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA, USA
| | - Kevin Sheerin
- Centre for Synthesis and Chemical Biology, University College of Dublin, Belfield, Dublin, 4, Ireland
| | - Arjun Raghuraman
- Department of Medicinal Chemistry and Institute of Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA, USA
| | - Florence Sallas
- Centre for Synthesis and Chemical Biology, University College of Dublin, Belfield, Dublin, 4, Ireland
| | - Philip D Mosier
- Department of Medicinal Chemistry and Institute of Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA, USA
| | - Nicholas D Watermeyer
- Centre for Synthesis and Chemical Biology, University College of Dublin, Belfield, Dublin, 4, Ireland
| | - Stefan Oscarson
- Centre for Synthesis and Chemical Biology, University College of Dublin, Belfield, Dublin, 4, Ireland
| | - Umesh R Desai
- Department of Medicinal Chemistry and Institute of Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA, USA
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A Hexasaccharide Containing Rare 2-O
-Sulfate-Glucuronic Acid Residues Selectively Activates Heparin Cofactor II. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201609541] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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30
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Meekins DA, Zhang X, Battaile KP, Lovell S, Michel K. 1.45 Å resolution structure of SRPN18 from the malaria vector Anopheles gambiae. Acta Crystallogr F Struct Biol Commun 2016; 72:853-862. [PMID: 27917832 PMCID: PMC5137461 DOI: 10.1107/s2053230x16017854] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 11/08/2016] [Indexed: 12/28/2022] Open
Abstract
Serine protease inhibitors (serpins) in insects function within development, wound healing and immunity. The genome of the African malaria vector, Anopheles gambiae, encodes 23 distinct serpin proteins, several of which are implicated in disease-relevant physiological responses. A. gambiae serpin 18 (SRPN18) was previously categorized as non-inhibitory based on the sequence of its reactive-center loop (RCL), a region responsible for targeting and initiating protease inhibition. The crystal structure of A. gambiae SRPN18 was determined to a resolution of 1.45 Å, including nearly the entire RCL in one of the two molecules in the asymmetric unit. The structure reveals that the SRPN18 RCL is extremely short and constricted, a feature associated with noncanonical inhibitors or non-inhibitory serpin superfamily members. Furthermore, the SRPN18 RCL does not contain a suitable protease target site and contains a large number of prolines. The SRPN18 structure therefore reveals a unique RCL architecture among the highly conserved serpin fold.
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Affiliation(s)
| | - Xin Zhang
- Division of Biology, Kansas State University, USA
| | - Kevin P. Battaile
- IMCA–CAT, Hauptman–Woodward Medical Research Institute, Argonne National Laboratory, USA
| | - Scott Lovell
- Protein Structure Laboratory, Del Shankel Structural Biology Center, University of Kansas, USA
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Dijk M, Holkers J, Voskamp P, Giannetti B, Waterreus WJ, van Veen H, Pannu N. How Dextran Sulfate Affects C1-inhibitor Activity: A Model for Polysaccharide Potentiation. Structure 2016; 24:2182-2189. [DOI: 10.1016/j.str.2016.09.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 07/14/2016] [Accepted: 10/05/2016] [Indexed: 11/25/2022]
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32
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Pica A, Russo Krauss I, Parente V, Tateishi-Karimata H, Nagatoishi S, Tsumoto K, Sugimoto N, Sica F. Through-bond effects in the ternary complexes of thrombin sandwiched by two DNA aptamers. Nucleic Acids Res 2016; 45:461-469. [PMID: 27899589 PMCID: PMC5224481 DOI: 10.1093/nar/gkw1113] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 10/20/2016] [Accepted: 10/29/2016] [Indexed: 11/23/2022] Open
Abstract
Aptamers directed against human thrombin can selectively bind to two different exosites on the protein surface. The simultaneous use of two DNA aptamers, HD1 and HD22, directed to exosite I and exosite II respectively, is a very powerful approach to exploit their combined affinity. Indeed, strategies to link HD1 and HD22 together have been proposed in order to create a single bivalent molecule with an enhanced ability to control thrombin activity. In this work, the crystal structures of two ternary complexes, in which thrombin is sandwiched between two DNA aptamers, are presented and discussed. The structures shed light on the cross talk between the two exosites. The through-bond effects are particularly evident at exosite II, with net consequences on the HD22 structure. Moreover, thermodynamic data on the binding of the two aptamers are also reported and analyzed.
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Affiliation(s)
- Andrea Pica
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia, I-80126 Naples, Italy.,Institute of Biostructures and Bioimaging, CNR, Via Mezzocannone, 16, I-80134 Naples, Italy
| | - Irene Russo Krauss
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia, I-80126 Naples, Italy.,Institute of Biostructures and Bioimaging, CNR, Via Mezzocannone, 16, I-80134 Naples, Italy
| | - Valeria Parente
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia, I-80126 Naples, Italy
| | - Hisae Tateishi-Karimata
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Kobe 650-0047, Japan
| | - Satoru Nagatoishi
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Kobe 650-0047, Japan.,Department of Bioengineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113- 8656, Japan
| | - Kouhei Tsumoto
- Department of Bioengineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113- 8656, Japan
| | - Naoki Sugimoto
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Kobe 650-0047, Japan .,Graduate School of Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan
| | - Filomena Sica
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia, I-80126 Naples, Italy .,Institute of Biostructures and Bioimaging, CNR, Via Mezzocannone, 16, I-80134 Naples, Italy
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Wei H, Cai H, Wu J, Wei Z, Zhang F, Huang X, Ma L, Feng L, Zhang R, Wang Y, Ragg H, Zheng Y, Zhou A. Heparin Binds Lamprey Angiotensinogen and Promotes Thrombin Inhibition through a Template Mechanism. J Biol Chem 2016; 291:24900-24911. [PMID: 27681598 DOI: 10.1074/jbc.m116.725895] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 08/20/2016] [Indexed: 01/01/2023] Open
Abstract
Lamprey angiotensinogen (l-ANT) is a hormone carrier in the regulation of blood pressure, but it is also a heparin-dependent thrombin inhibitor in lamprey blood coagulation system. The detailed mechanisms on how angiotensin is carried by l-ANT and how heparin binds l-ANT and mediates thrombin inhibition are unclear. Here we have solved the crystal structure of cleaved l-ANT at 2.7 Å resolution and characterized its properties in heparin binding and protease inhibition. The structure reveals that l-ANT has a conserved serpin fold with a labile N-terminal angiotensin peptide and undergoes a typical stressed-to-relaxed conformational change when the reactive center loop is cleaved. Heparin binds l-ANT tightly with a dissociation constant of ∼10 nm involving ∼8 monosaccharides and ∼6 ionic interactions. The heparin binding site is located in an extensive positively charged surface area around helix D involving residues Lys-148, Lys-151, Arg-155, and Arg-380. Although l-ANT by itself is a poor thrombin inhibitor with a second order rate constant of 500 m-1 s-1, its interaction with thrombin is accelerated 90-fold by high molecular weight heparin following a bell-shaped dose-dependent curve. Short heparin chains of 6-20 monosaccharide units are insufficient to promote thrombin inhibition. Furthermore, an l-ANT mutant with the P1 Ile mutated to Arg inhibits thrombin nearly 1500-fold faster than the wild type, which is further accelerated by high molecular weight heparin. Taken together, these results suggest that heparin binds l-ANT at a conserved heparin binding site around helix D and promotes the interaction between l-ANT and thrombin through a template mechanism conserved in vertebrates.
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Affiliation(s)
- Hudie Wei
- From the Hongqiao International Institute of Medicine, Shanghai Tongren Hospital/Faculty of Basic Medicine, Chemical Biology Division of Shanghai Universities E-Institutes, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China and
| | - Haiyan Cai
- From the Hongqiao International Institute of Medicine, Shanghai Tongren Hospital/Faculty of Basic Medicine, Chemical Biology Division of Shanghai Universities E-Institutes, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China and
| | - Jiawei Wu
- From the Hongqiao International Institute of Medicine, Shanghai Tongren Hospital/Faculty of Basic Medicine, Chemical Biology Division of Shanghai Universities E-Institutes, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China and
| | - Zhenquan Wei
- From the Hongqiao International Institute of Medicine, Shanghai Tongren Hospital/Faculty of Basic Medicine, Chemical Biology Division of Shanghai Universities E-Institutes, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China and
| | - Fei Zhang
- From the Hongqiao International Institute of Medicine, Shanghai Tongren Hospital/Faculty of Basic Medicine, Chemical Biology Division of Shanghai Universities E-Institutes, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China and
| | - Xin Huang
- From the Hongqiao International Institute of Medicine, Shanghai Tongren Hospital/Faculty of Basic Medicine, Chemical Biology Division of Shanghai Universities E-Institutes, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China and
| | - Lina Ma
- From the Hongqiao International Institute of Medicine, Shanghai Tongren Hospital/Faculty of Basic Medicine, Chemical Biology Division of Shanghai Universities E-Institutes, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China and
| | - Lingling Feng
- From the Hongqiao International Institute of Medicine, Shanghai Tongren Hospital/Faculty of Basic Medicine, Chemical Biology Division of Shanghai Universities E-Institutes, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China and
| | - Ruoxi Zhang
- From the Hongqiao International Institute of Medicine, Shanghai Tongren Hospital/Faculty of Basic Medicine, Chemical Biology Division of Shanghai Universities E-Institutes, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China and
| | - Yunjie Wang
- the Faculty of Technology, Bielefeld University, 33613 Bielefeld, Germany
| | - Hermann Ragg
- the Faculty of Technology, Bielefeld University, 33613 Bielefeld, Germany
| | - Ying Zheng
- From the Hongqiao International Institute of Medicine, Shanghai Tongren Hospital/Faculty of Basic Medicine, Chemical Biology Division of Shanghai Universities E-Institutes, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China and
| | - Aiwu Zhou
- From the Hongqiao International Institute of Medicine, Shanghai Tongren Hospital/Faculty of Basic Medicine, Chemical Biology Division of Shanghai Universities E-Institutes, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China and
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34
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Serpins in arthropod biology. Semin Cell Dev Biol 2016; 62:105-119. [PMID: 27603121 DOI: 10.1016/j.semcdb.2016.09.001] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 08/31/2016] [Accepted: 09/02/2016] [Indexed: 12/21/2022]
Abstract
Serpins are the largest known family of serine proteinase inhibitors and perform a variety of physiological functions in arthropods. Herein, we review the field of serpins in arthropod biology, providing an overview of current knowledge and topics of interest. Serpins regulate insect innate immunity via inhibition of serine proteinase cascades that initiate immune responses such as melanization and antimicrobial peptide production. In addition, several serpins with anti-pathogen activity are expressed as acute-phase serpins in insects upon infection. Parasitoid wasps can downregulate host serpin expression to modulate the host immune system. In addition, examples of serpin activity in development and reproduction in Drosophila have also been discovered. Serpins also function in host-pathogen interactions beyond immunity as constituents of venom in parasitoid wasps and saliva of blood-feeding ticks and mosquitoes. These serpins have distinct effects on immunosuppression and anticoagulation and are of interest for vaccine development. Lastly, the known structures of arthropod serpins are discussed, which represent the serpin inhibitory mechanism and provide a detailed overview of the process.
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35
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Mulloy B, Hogwood J, Gray E, Lever R, Page CP. Pharmacology of Heparin and Related Drugs. Pharmacol Rev 2016; 68:76-141. [PMID: 26672027 DOI: 10.1124/pr.115.011247] [Citation(s) in RCA: 216] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Heparin has been recognized as a valuable anticoagulant and antithrombotic for several decades and is still widely used in clinical practice for a variety of indications. The anticoagulant activity of heparin is mainly attributable to the action of a specific pentasaccharide sequence that acts in concert with antithrombin, a plasma coagulation factor inhibitor. This observation has led to the development of synthetic heparin mimetics for clinical use. However, it is increasingly recognized that heparin has many other pharmacological properties, including but not limited to antiviral, anti-inflammatory, and antimetastatic actions. Many of these activities are independent of its anticoagulant activity, although the mechanisms of these other activities are currently less well defined. Nonetheless, heparin is being exploited for clinical uses beyond anticoagulation and developed for a wide range of clinical disorders. This article provides a "state of the art" review of our current understanding of the pharmacology of heparin and related drugs and an overview of the status of development of such drugs.
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Affiliation(s)
- Barbara Mulloy
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (B.M., C.P.P.); National Institute for Biological Standards and Control, Potters Bar, Hertfordshire, United Kingdom (J.H., E.G.); and University College London School of Pharmacy, London, United Kingdom (R.L.)
| | - John Hogwood
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (B.M., C.P.P.); National Institute for Biological Standards and Control, Potters Bar, Hertfordshire, United Kingdom (J.H., E.G.); and University College London School of Pharmacy, London, United Kingdom (R.L.)
| | - Elaine Gray
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (B.M., C.P.P.); National Institute for Biological Standards and Control, Potters Bar, Hertfordshire, United Kingdom (J.H., E.G.); and University College London School of Pharmacy, London, United Kingdom (R.L.)
| | - Rebecca Lever
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (B.M., C.P.P.); National Institute for Biological Standards and Control, Potters Bar, Hertfordshire, United Kingdom (J.H., E.G.); and University College London School of Pharmacy, London, United Kingdom (R.L.)
| | - Clive P Page
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (B.M., C.P.P.); National Institute for Biological Standards and Control, Potters Bar, Hertfordshire, United Kingdom (J.H., E.G.); and University College London School of Pharmacy, London, United Kingdom (R.L.)
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36
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Trapaidze A, Hérault JP, Herbert JM, Bancaud A, Gué AM. Investigation of the selectivity of thrombin-binding aptamers for thrombin titration in murine plasma. Biosens Bioelectron 2015; 78:58-66. [PMID: 26594887 DOI: 10.1016/j.bios.2015.11.017] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 10/26/2015] [Accepted: 11/08/2015] [Indexed: 11/26/2022]
Abstract
Detection of thrombin in plasma raises timely challenges to enable therapeutic management of thrombosis in patients under vital threat. Thrombin binding aptamers represent promising candidates as sensing elements for the development of real-time thrombin biosensors; however implementation of such biosensor requires the clear understanding of thrombin-aptamer interaction properties in real-like environment. In this study, we used Surface Plasmon Resonance technique to answer the questions of specificity and sensitivity of thrombin detection by the thrombin-binding aptamers HD1, NU172 and HD22. We systematically characterized their properties in the presence of thrombin, as well as interfering molecular species such as the thrombin precursor prothrombin, thrombin in complex with some of its natural inhibitors, nonspecific serum proteins, and diluted plasma. Kinetic experiments show the multiple binding modes of HD1 and NU172, which both interact with multiple sites of thrombin with low nanomolar affinities and show little specificity of interaction for prothrombin vs. thrombin. HD22, on the other hand, binds specifically to thrombin exosite II and has no affinity to prothrombin at all. While thrombin in complex with some of its inhibitors could not be recognized by any aptamer, the binding of HD1 and NU172 properties is compromised by thrombin inhibitors alone, as well as with serum albumin. Finally, the complex nature of plasma was overwhelming for HD1, but we define conditions for the thrombin detection at 10nM range in 100-fold diluted plasma by HD22. Consequently HD22 showed key advantage over HD1 and NU172, and appears as the only alternative to design an aptasensor.
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Affiliation(s)
- Ana Trapaidze
- CNRS, LAAS, 7 avenue du colonel Roche, F-31400 Toulouse, France; Université de Toulouse, LAAS, F-31400 Toulouse, France.
| | | | | | - Aurélien Bancaud
- CNRS, LAAS, 7 avenue du colonel Roche, F-31400 Toulouse, France; Université de Toulouse, LAAS, F-31400 Toulouse, France.
| | - Anne-Marie Gué
- CNRS, LAAS, 7 avenue du colonel Roche, F-31400 Toulouse, France; Université de Toulouse, LAAS, F-31400 Toulouse, France
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Xu T, Lew-Tabor A, Rodriguez-Valle M. Effective inhibition of thrombin by Rhipicephalus microplus serpin-15 (RmS-15) obtained in the yeast Pichia pastoris. Ticks Tick Borne Dis 2015; 7:180-187. [PMID: 26530984 DOI: 10.1016/j.ttbdis.2015.09.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 09/10/2015] [Accepted: 09/25/2015] [Indexed: 10/22/2022]
Abstract
The cattle tick (Rhipicephalus microplus) affects cattle industries in tropical and subtropical countries because it is the vector of babesiosis and anaplasmosis which constitutes a threat to the health of cattle. During blooding feeding, ticks secrete saliva containing a complex of bioactive molecules into the injured site to evade host's defensive responses. Serine protease inhibitors (serpins) are important anti-haemostatic molecules present in tick saliva that are necessary for a successful blood feeding. Several serpin sequences have been reported in R. microplus but there is a gap of information about their functions during host-parasite interactions. In this study, the RmS-15 expressed in the yeast Pichia pastoris was characterised using kinetic assays and in vitro analysis. The inhibitory enzymatic assays conducted showed that RmS-15 is a physiological inhibitor of thrombin with a stoichiometric inhibition (SI) of 1.5 and high inhibition affinity with ka=9.3±0.5×104M(-1)s(-1). RmS-15 delayed the clotting of plasma in a dose-dependent manner as determined in a recalcification time assay. Significant elevated ELISA titres were observed in tick resistant and susceptible cattle on day 28 after the tick infestation (p<0.001). This data suggests direct contact of RmS-15 with the immune system of the host at the tick-feeding site. The present study contributed to the understanding of the biological functions of R. microplus serpins during host-parasite interactions which contributes to the design of future innovative methods for tick control.
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Affiliation(s)
- Tao Xu
- The University of Queensland, Queensland Alliance for Agriculture & Food Innovation, Qld, Australia
| | - Ala Lew-Tabor
- The University of Queensland, Queensland Alliance for Agriculture & Food Innovation, Qld, Australia; Murdoch University, Centre for Comparative Genomics, Perth, Western Australia 6150, Australia
| | - Manuel Rodriguez-Valle
- The University of Queensland, Queensland Alliance for Agriculture & Food Innovation, Qld, Australia.
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Razali N, Abdul Aziz A, Lim CY, Mat Junit S. Investigation into the effects of antioxidant-rich extract of Tamarindus indica leaf on antioxidant enzyme activities, oxidative stress and gene expression profiles in HepG2 cells. PeerJ 2015; 3:e1292. [PMID: 26557426 PMCID: PMC4636403 DOI: 10.7717/peerj.1292] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 09/14/2015] [Indexed: 12/31/2022] Open
Abstract
The leaf extract of Tamarindus indica L. (T. indica) had been reported to possess high phenolic content and showed high antioxidant activities. In this study, the effects of the antioxidant-rich leaf extract of the T. indica on lipid peroxidation, antioxidant enzyme activities, H2O2-induced ROS production and gene expression patterns were investigated in liver HepG2 cells. Lipid peroxidation and ROS production were inhibited and the activity of antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase was enhanced when the cells were treated with the antioxidant-rich leaf extract. cDNA microarray analysis revealed that 207 genes were significantly regulated by at least 1.5-fold (p < 0.05) in cells treated with the antioxidant-rich leaf extract. The expression of KNG1, SERPINC1, SERPIND1, SERPINE1, FGG, FGA, MVK, DHCR24, CYP24A1, ALDH6A1, EPHX1 and LEAP2 were amongst the highly regulated. When the significantly regulated genes were analyzed using Ingenuity Pathway Analysis software, “Lipid Metabolism, Small Molecule Biochemistry, Hematological Disease” was the top biological network affected by the leaf extract, with a score of 36. The top predicted canonical pathway affected by the leaf extract was the coagulation system (P < 2.80 × 10−6) followed by the superpathway of cholesterol biosynthesis (P < 2.17 × 10−4), intrinsic prothrombin pathway (P < 2.92 × 10−4), Immune Protection/Antimicrobial Response (P < 2.28 × 10−3) and xenobiotic metabolism signaling (P < 2.41 × 10−3). The antioxidant-rich leaf extract of T. indica also altered the expression of proteins that are involved in the Coagulation System and the Intrinsic Prothrombin Activation Pathway (KNG1, SERPINE1, FGG), Superpathway of Cholesterol Biosynthesis (MVK), Immune protection/antimicrobial response (IFNGR1, LEAP2, ANXA3 and MX1) and Xenobiotic Metabolism Signaling (ALDH6A1, ADH6). In conclusion, the antioxidant-rich leaf extract of T. indica inhibited lipid peroxidation and ROS production, enhanced antioxidant enzyme activities and significantly regulated the expression of genes and proteins involved with consequential impact on the coagulation system, cholesterol biosynthesis, xenobiotic metabolism signaling and antimicrobial response.
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Affiliation(s)
- Nurhanani Razali
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya , Kuala Lumpur , Malaysia
| | - Azlina Abdul Aziz
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya , Kuala Lumpur , Malaysia
| | - Chor Yin Lim
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya , Kuala Lumpur , Malaysia
| | - Sarni Mat Junit
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya , Kuala Lumpur , Malaysia
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Gierczak RF, Bhakta V, Xie M, Sheffield WP. Comparison of mammalian and bacterial expression library screening to detect recombinant alpha-1 proteinase inhibitor variants with enhanced thrombin inhibitory capacity. J Biotechnol 2015; 208:54-62. [PMID: 26043905 DOI: 10.1016/j.jbiotec.2015.05.019] [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: 01/06/2015] [Accepted: 05/27/2015] [Indexed: 11/29/2022]
Abstract
Serpins are a widely distributed family of serine protease inhibitors. A key determinant of their specificity is the reactive centre loop (RCL), a surface motif of ∼20 amino acids in length. Expression libraries of variant serpins could be rapidly probed with proteases to develop novel inhibitors if optimal systems were available. The serpin variant alpha-1 proteinase inhibitor M358R (API M358R) inhibits the coagulation protease thrombin, but at sub-maximal rates compared to other serpins. Here we compared two approaches to isolate functional API variants from serpin expression libraries, using the same small library of API randomized at residue 358 (M358X): flow cytometry of transfected HEK 293 cells expressing membrane-displayed API; and a thrombin capture assay (TCA) performed on pools of bacterial lysates expressing soluble API. No enrichment for specific P1 residues was observed when the RCL codons of the 1% of sorted transfected 293 cells with the highest fluorescent thrombin-binding signals were subcloned and sequenced. In contrast, screening of 16 pools of bacterial API-expressing transformants led to the facile identification of API M358R and M358K as functional variants. Kinetic characterization showed that API M358R inhibited thrombin 17-fold more rapidly than API M358K. Reducing the incubation time with immobilized thrombin improved the sensitivity of TCA to detect supra-active API M358R variants and was used to screen a hypervariable library of API variants expressing 16 different amino acids at residues 352-357. The most active variant isolated, with TLSATP substituted for FLEAI, inhibited thrombin 2.9-fold more rapidly than API M358R. Our results indicate that flow cytometric approaches used in protein engineering of antibodies are not appropriate for serpins, and highlight the utility of the optimized TCA for serpin protein engineering.
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Affiliation(s)
- Richard F Gierczak
- Department of Pathology and Molecular Medicine, McMasterUniversity, Hamilton, Ontario, Canada
| | - Varsha Bhakta
- Canadian Blood Services, Centre for Innovation, Hamilton, Ontario, Canada
| | - Michael Xie
- Department of Pathology and Molecular Medicine, McMasterUniversity, Hamilton, Ontario, Canada
| | - William P Sheffield
- Department of Pathology and Molecular Medicine, McMasterUniversity, Hamilton, Ontario, Canada; Canadian Blood Services, Centre for Innovation, Hamilton, Ontario, Canada.
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Valdivieso E, Perteguer MJ, Hurtado C, Campioli P, Rodríguez E, Saborido A, Martínez-Sernández V, Gómez-Puertas P, Ubeira FM, Gárate T. ANISERP: a new serpin from the parasite Anisakis simplex. Parasit Vectors 2015; 8:399. [PMID: 26215984 PMCID: PMC4517634 DOI: 10.1186/s13071-015-1006-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 07/11/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Serine proteinase inhibitors (serpins) finely regulate serine proteinase activity via a suicide substrate-like inhibitory mechanism. In parasitic nematodes, some serpins interact with host physiological processes; however, little is known about these essential molecules in Anisakis. This article reports the gene sequencing, cloning, expression and preliminary biochemical and bioinformatically-based structural characterization of a new Anisakis serpin (ANISERP). METHODS The full AniSerp gene was cloned by specific RACE-PCR after screening an Anisakis simplex (L3) cDNA library. For biochemical assays, the AniSerp gene was subcloned into both prokaryotic and eukaryotic vectors, and the recombinant proteins were purified. The inhibitory properties of the proteins were tested in classical biochemical assays using human serine peptidases and AMC substrates. Immunolocalization of ANISERP, theoretical structural analysis and bioinformatically-based structural modelling of the ANISERP protein were also conducted. RESULTS The AniSerp gene was found to have 1194 nucleotides, coding for a protein of 397 amino acid residues plus a putative N-terminal signal peptide. It showed significant similarity to other nematode, arthropod and mammalian serpins. The recombinant ANISERP expressed in the prokaryotic and eukaryotic systems inhibited the human serine proteases thrombin, trypsin and cathepsin G in a concentration-dependent manner. No inhibitory activity against Factor Xa, Factor XIa, Factor XIIa, elastase, plasmin or chymotrypsin was observed. ANISERP also acted on the cysteine protease cathepsin L. ANISERP was mainly localized in the nematode pseudocoelomic fluid, somatic muscle cell bodies and intestinal cells. The findings of molecular dynamics studies suggest that ANISERP inhibits thrombin via a suicide substrate-like inhibitory mechanism, similar to the mechanism of action of mammalian coagulation inhibitors. In contrast to findings concerning human antithrombin III, heparin had no effect on ANISERP anticoagulant inhibitory activity. CONCLUSIONS Our findings suggest that ANISERP is an internal Anisakis regulatory serpin and that the inhibitory activity against thrombin depends on a suicide substrate-like inhibitory mechanism, similar to that described for human antithrombin (AT)-III. The fact that heparin does not modulate the anticoagulant activity of ANISERP might be explained by the absence in the latter of five of the six positively charged residues usually seen at the AT-III-heparin binding site.
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Affiliation(s)
- Elizabeth Valdivieso
- Servicio de Parasitología, Centro Nacional de Microbiología, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain.
- Laboratorio de Biología Celular de Parásitos, Instituto de Biología Experimental, Facultad de Ciencias, Universidad Central de Venezuela, 47069, Caracas, 1041-A, Venezuela.
| | - Maria J Perteguer
- Servicio de Parasitología, Centro Nacional de Microbiología, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain.
- Parasitology Department, Centro Nacional de Microbiología, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain.
| | - Carolina Hurtado
- Servicio de Parasitología, Centro Nacional de Microbiología, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain.
- Present Address: Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad San Pablo-CEU, Campus de Montepríncipe, Urb. Montepríncipe, 28668, Madrid, Spain.
| | - Pamela Campioli
- Servicio de Parasitología, Centro Nacional de Microbiología, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain.
| | - Esperanza Rodríguez
- Servicio de Parasitología, Centro Nacional de Microbiología, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain.
| | - Ana Saborido
- Departamento de Bioquímica y Biología Molecular I, Facultad de Químicas, Universidad Complutense, Madrid, Spain.
| | | | - Paulino Gómez-Puertas
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM) Campus UAM. Cantoblanco, 28049, Madrid, Spain.
| | - Florencio M Ubeira
- Laboratorio de Parasitología, Facultad de Farmacia, Universidad de Santiago de Compostela, A Coruña, Spain.
| | - Teresa Gárate
- Servicio de Parasitología, Centro Nacional de Microbiología, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain.
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A unique serpin P1' glutamate and a conserved β-sheet C arginine are key residues for activity, protease recognition and stability of serpinA12 (vaspin). Biochem J 2015. [PMID: 26199422 DOI: 10.1042/bj20150643] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
SerpinA12 (vaspin) is thought to be mainly expressed in adipose tissue and has multiple beneficial effects on metabolic, inflammatory and atherogenic processes related to obesity. KLK7 (kallikrein 7) is the only known protease target of vaspin to date and is inhibited with a moderate inhibition rate. In the crystal structure, the cleavage site (P1-P1') of the vaspin reactive centre loop is fairly rigid compared with the flexible residues before P2, possibly supported by an ionic interaction of P1' glutamate (Glu(379)) with an arginine residue (Arg(302)) of the β-sheet C. A P1' glutamate seems highly unusual and unfavourable for the protease KLK7. We characterized vaspin mutants to investigate the roles of these two residues in protease inhibition and recognition by vaspin. Reactive centre loop mutations changing the P1' residue or altering the reactive centre loop conformation significantly increased inhibition parameters, whereas removal of the positive charge within β-sheet C impeded the serpin-protease interaction. Arg(302) is a crucial contact to enable vaspin recognition by KLK7 and it supports moderate inhibition of the serpin despite the presence of the detrimental P1' Glu(379), which clearly represents a major limiting factor for vaspin-inhibitory activity. We also show that the vaspin-inhibition rate for KLK7 can be modestly increased by heparin and demonstrate that vaspin is a heparin-binding serpin. Noteworthily, we observed vaspin as a remarkably thermostable serpin and found that Glu(379) and Arg(302) influence heat-induced polymerization. These structural and functional results reveal the mechanistic basis of how reactive centre loop sequence and exosite interaction in vaspin enable KLK7 recognition and regulate protease inhibition as well as stability of this adipose tissue-derived serpin.
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Naudin C, Hurley SM, Malmström E, Plug T, Shannon O, Meijers JCM, Mörgelin M, Björck L, Herwald H. Active but inoperable thrombin is accumulated in a plasma protein layer surrounding Streptococcus pyogenes. Thromb Haemost 2015; 114:717-26. [PMID: 25994766 DOI: 10.1160/th15-02-0127] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 04/15/2015] [Indexed: 12/23/2022]
Abstract
Activation of thrombin is a critical determinant in many physiological and pathological processes including haemostasis and inflammation. Under physiological conditions many of these functions are involved in wound healing or eradication of an invading pathogen. However, when activated systemically, thrombin can contribute to severe and life-threatening conditions by causing complications such as multiple multi-organ failure and disseminated intravascular coagulation. In the present study we investigated how the activity of thrombin is modulated when it is bound to the surface of Streptococcus pyogenes. Our data show that S. pyogenes bacteria become covered with a proteinaceous layer when incubated with human plasma, and that thrombin is a constituent of this layer. Though the coagulation factor is found attached to the bacteria with a functional active site, thrombin has lost its capacity to interact with its natural substrates and inhibitors. Thus, the interaction of bacteria with human plasma renders thrombin completely inoperable at the streptococcal surface. This could represent a host defense mechanism to avoid systemic activation of coagulation which could be otherwise induced when bacteria enter the circulation and cause systemic infection.
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Affiliation(s)
- Clément Naudin
- Clément Naudin, Department of Clinical Sciences, Division of Infection Medicine, Lund University, Biomedical Center (BMC), Floor B14, Tornavägen 10, 22184 Lund, Sweden, Tel.: + 46 46 2226807, Fax: + 46 46 157756, E-mail:
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Zhang X, Meekins DA, An C, Zolkiewski M, Battaile KP, Kanost MR, Lovell S, Michel K. Structural and inhibitory effects of hinge loop mutagenesis in serpin-2 from the malaria vector Anopheles gambiae. J Biol Chem 2014; 290:2946-56. [PMID: 25525260 DOI: 10.1074/jbc.m114.625665] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Serpin-2 (SRPN2) is a key negative regulator of the melanization response in the malaria vector Anopheles gambiae. SRPN2 irreversibly inhibits clip domain serine proteinase 9 (CLIPB9), which functions in a serine proteinase cascade culminating in the activation of prophenoloxidase and melanization. Silencing of SRPN2 in A. gambiae results in spontaneous melanization and decreased life span and is therefore a promising target for vector control. The previously determined structure of SRPN2 revealed a partial insertion of the hinge region of the reactive center loop (RCL) into β sheet A. This partial hinge insertion participates in heparin-linked activation in other serpins, notably antithrombin III. SRPN2 does not contain a heparin binding site, and any possible mechanistic function of the hinge insertion was previously unknown. To investigate the function of the SRPN2 hinge insertion, we developed three SRPN2 variants in which the hinge regions are either constitutively expelled or inserted and analyzed their structure, thermostability, and inhibitory activity. We determined that constitutive hinge expulsion resulted in a 2.7-fold increase in the rate of CLIPB9Xa inhibition, which is significantly lower than previous observations of allosteric serpin activation. Furthermore, we determined that stable insertion of the hinge region did not appreciably decrease the accessibility of the RCL to CLIPB9. Together, these results indicate that the partial hinge insertion in SRPN2 does not participate in the allosteric activation observed in other serpins and instead represents a molecular trade-off between RCL accessibility and efficient formation of an inhibitory complex with the cognate proteinase.
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Affiliation(s)
- Xin Zhang
- From the Division of Biology, Kansas State University, Manhattan, Kansas 66506
| | - David A Meekins
- From the Division of Biology, Kansas State University, Manhattan, Kansas 66506
| | - Chunju An
- From the Division of Biology, Kansas State University, Manhattan, Kansas 66506, the Department of Entomology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, China
| | - Michal Zolkiewski
- the Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506
| | - Kevin P Battaile
- Industrial Macromolecular Crystallography Association Collaborative Access Team, Hauptman-Woodward Medical Research Institute, Advanced Photon Source Argonne National Laboratory, Argonne, Illinois 60439, and
| | - Michael R Kanost
- the Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506
| | - Scott Lovell
- the Protein Structure Laboratory, Del Shankel Structural Biology Center, University of Kansas, Lawrence, Kansas 66407
| | - Kristin Michel
- From the Division of Biology, Kansas State University, Manhattan, Kansas 66506,
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Chan WL, Zhou A, Read RJ. Towards engineering hormone-binding globulins as drug delivery agents. PLoS One 2014; 9:e113402. [PMID: 25426859 PMCID: PMC4245140 DOI: 10.1371/journal.pone.0113402] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Accepted: 10/24/2014] [Indexed: 12/05/2022] Open
Abstract
The treatment of many diseases such as cancer requires the use of drugs that can cause severe side effects. Off-target toxicity can often be reduced simply by directing the drugs specifically to sites of diseases. Amidst increasingly sophisticated methods of targeted drug delivery, we observed that Nature has already evolved elegant means of sending biological molecules to where they are needed. One such example is corticosteroid binding globulin (CBG), the major carrier of the anti-inflammatory hormone, cortisol. Targeted release of cortisol is triggered by cleavage of CBG's reactive centre loop by elastase, a protease released by neutrophils in inflamed tissues. This work aimed to establish the feasibility of exploiting this mechanism to carry therapeutic agents to defined locations. The reactive centre loop of CBG was altered with site-directed mutagenesis to favour cleavage by other proteases, to alter the sites at which it would release its cargo. Mutagenesis succeeded in making CBG a substrate for either prostate specific antigen (PSA), a prostate-specific serine protease, or thrombin, a key protease in the blood coagulation cascade. PSA is conspicuously overproduced in prostatic hyperplasia and is, therefore, a good way of targeting hyperplastic prostate tissues. Thrombin is released during clotting and consequently is ideal for conferring specificity to thrombotic sites. Using fluorescence-based titration assays, we also showed that CBG can be engineered to bind a new compound, thyroxine-6-carboxyfluorescein, instead of its physiological ligand, cortisol, thereby demonstrating that it is possible to tailor the hormone binding site to deliver a therapeutic drug. In addition, we proved that the efficiency with which CBG releases bound ligand can be increased by introducing some well-placed mutations. This proof-of-concept study has raised the prospect of a novel means of targeted drug delivery, using the serpin conformational change to combat the problem of off-target effects in the treatment of diseases.
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Affiliation(s)
- Wee Lee Chan
- Department of Haematology, University of Cambridge, Cambridge Institute for Medical Research, Addenbrooke's Hospital, Cambridge, United Kingdom
| | - Aiwu Zhou
- Key Laboratory of Cell Differentiation and Apoptosis of Ministry of Education of China, Shanghai Jiao Tong University, School of Medicine, Shanghai, People's Republic of China
| | - Randy J. Read
- Department of Haematology, University of Cambridge, Cambridge Institute for Medical Research, Addenbrooke's Hospital, Cambridge, United Kingdom
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Sheffield WP, Lambourne MD, Eltringham-Smith LJ, Bhakta V, Arnold DM, Crowther MA. γT -S195A thrombin reduces the anticoagulant effects of dabigatran in vitro and in vivo. J Thromb Haemost 2014; 12:1110-5. [PMID: 24815541 DOI: 10.1111/jth.12601] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Accepted: 05/05/2014] [Indexed: 12/13/2022]
Abstract
BACKGROUND Dabigatran etexilate (DE) is an oral direct thrombin inhibitor used to prevent strokes in patients with atrial fibrillation. No licensed DE antidote is currently available. We hypothesized that active site-mutated S195A thrombin (S195A-IIa) and/or its trypsinized derivative (γT -S195A-IIa) would sequester dabigatran, the active form of DE, and reduce its anticoagulant effects. OBJECTIVE To assess active site-mutated S195A or γT -S195A-IIa as dabigatran reversal agents in vitro and in vivo. METHODS Diluted thrombin time (dTT) assays were performed using human or murine plasma containing dabigatran, combined with S195A-IIa, γT -S195A-IIa or FPR-chloromethyl ketone-treated thrombin (FPR-IIa). Bleeding times were determined in anesthetized DE-treated mice also receiving γT -S195A-IIa or vehicle 15 min prior to tail transection. The time to occlusion of carotid arteries of DE-treated mice also receiving S195A-IIa, γT -S195A-IIa, prothrombin complex concentrate (PCC) or vehicle, 15 min prior to topical FeCl3 , was determined using Doppler ultrasound. RESULTS γT-S195A-IIa reduced dTT values of dabigatran-containing human and murine plasma more effectively than S195-IIa; FPR-IIa had no effect. A dose of 13 mg kg(-1) DE abrogated occlusive thrombus formation in the carotid arteries of FeCl3 -treated mice; γT -S195A-IIa (6 mg kg(-1) ) or PCC (14.3 IU kg(-1) ), but not saline vehicle or S195A-IIa (6 mg kg(-1) ), was equally effective in restoring thrombus formation. Bleeding times of mice treated with 60 mg kg(-1) DE and γT -S195A-IIa (6 mg kg(-1) ) or saline vehicle did not differ. CONCLUSIONS Our data suggest that γT -S195A-IIa decreases the anticoagulant effects of dabigatran in vitro and is partially effective at restoring hemostasis-related thrombus formation in DE-treated mice in vivo.
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Affiliation(s)
- W P Sheffield
- Canadian Blood Services, Centre for Innovation, Hamilton, ON, Canada; Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada
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Kumar A, Bhandari A, Sarde SJ, Goswami C. Genetic variants and evolutionary analyses of heparin cofactor II. Immunobiology 2014; 219:713-28. [PMID: 24950623 DOI: 10.1016/j.imbio.2014.05.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 04/13/2014] [Accepted: 05/19/2014] [Indexed: 11/25/2022]
Abstract
Heparin cofactor II (HCII) belongs to serpin superfamily and it acts as a thrombin inhibitor in the coagulation cascade, in a glycosaminoglycan-dependent pathway using the release of a sequestered hirudin-like N-terminal tail for interaction with thrombin. This serpin belongs to multiple member group V2 of vertebrate serpin classification. However, there is no comprehensive study illustrating the exact phylogenetic history of HCII, to date. Herein, we explored phylogenetic traits of HCII genes. Structures of HCII gene from selected ray-finned fishes and lamprey varied in exon I and II with insertions of novel introns of which one in core domain for ray-finned fishes in exon II at the position 241c. We found HCII remain nested in the largest intron of phosphatidylinositol (PI) 4-kinase (PIK4CA) gene (genetic variants of this gene cause schizophrenia) at the origin of vertebrates, dated about 500MY old. We found that sequence features such as two acidic repeats (AR1-II), GAG-binding helix-D, three serpin motifs and inhibitory reactive center loop (RCL) of HCII protein are highly conserved in 55 vertebrates analyzed. We identified 985 HCII variants by analysis of 1092 human genomes with top three variation classes belongs to SNPs (84.3%), insertion (7.1%) and deletion (5.0%). We identified 37 deleterious mutations in the human HCII protein and we have described these mutations in relation to HCII sequence-structure-function relationships. These understandings may have clinical and medical importance as well.
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Affiliation(s)
- Abhishek Kumar
- Department of Genetics & Molecular Biology in Botany, Institute of Botany, Christian-Albrechts-University at Kiel, Kiel, Germany.
| | - Anita Bhandari
- Molecular Physiology, Zoological Institute, Christian-Albrechts-University at Kiel, Kiel, Germany
| | - Sandeep J Sarde
- Department of Genetics & Molecular Biology in Botany, Institute of Botany, Christian-Albrechts-University at Kiel, Kiel, Germany; Master Program Agrigenomics, Christian-Albrechts-University at Kiel, Kiel, Germany
| | - Chandan Goswami
- National Institute of Science Education and Research, Bhubaneswar, Orissa, India
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Huntington JA. Natural inhibitors of thrombin. Thromb Haemost 2014; 111:583-9. [PMID: 24477356 DOI: 10.1160/th13-10-0811] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 12/31/2013] [Indexed: 11/05/2022]
Abstract
The serine protease thrombin is the effector enzyme of blood coagulation. It has many activities critical for the formation of stable clots, including cleavage of fibrinogen to fibrin, activation of platelets and conversion of procofactors to active cofactors. Thrombin carries-out its multiple functions by utilising three special features: a deep active site cleft and two anion binding exosites (exosite I and II). Similarly, thrombin inhibitors have evolved to exploit the unique features of thrombin to achieve rapid and specific inactivation of thrombin. Exogenous thrombin inhibitors come from several different protein families and are generally found in the saliva of haematophagous animals (blood suckers) as part of an anticoagulant cocktail that allows them to feed. Crystal structures of several of these inhibitors reveal how peptides and proteins can be targeted to thrombin in different and interesting ways. Thrombin activity must also be regulated by endogenous inhibitors so that thrombi do not occlude blood flow and cause thrombosis. A single protein family, the serpins, provides all four of the endogenous thrombin inhibitors found in man. The crystal structures of these serpins bound to thrombin have been solved, revealing a similar exosite-dependence on complex formation. In addition to forming the recognition complex, serpins destroy the structure of thrombin, allowing them to be released from cofactors and substrates for clearance. This review examines how the special features of thrombin have been exploited by evolution to achieve inhibition of the ultimate coagulation protease.
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Affiliation(s)
- James A Huntington
- James A. Huntington, Department of Haematology, University of Cambridge, Cambridge Institute for Medical Research, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 0XY, UK, Tel.: +44 1223 763230, Fax: +44 1223 336827, E-mail:
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Ballut L, Sapay N, Chautard E, Imberty A, Ricard-Blum S. Mapping of heparin/heparan sulfate binding sites on αvβ3 integrin by molecular docking. J Mol Recognit 2013; 26:76-85. [PMID: 23334915 DOI: 10.1002/jmr.2250] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 10/15/2012] [Accepted: 10/15/2012] [Indexed: 01/24/2023]
Abstract
Heparin/heparan sulfate interact with growth factors, chemokines, extracellular proteins, and receptors. Integrins are αβ heterodimers that serve as receptors for extracellular proteins, regulate cell behavior, and participate in extracellular matrix assembly. Heparin binds to RGD-dependent integrins (αIIbβ3, α5β1, αvβ3, and αvβ5) and to RGD-independent integrins (α4β1, αXβ2, and αMβ2), but their binding sites have not been located on integrins. We report the mapping of heparin binding sites on the ectodomain of αvβ3 integrin by molecular modeling. The surface of the ectodomain was scanned with small rigid probes mimicking the sulfated domains of heparan sulfate. Docking results were clustered into binding spots. The best results were selected for further docking simulations with heparin hexasaccharide. Six potential binding spots containing lysine and/or arginine residues were identified on the ectodomain of αvβ3 integrin. Heparin would mostly bind to the top of the genu domain, the Calf-I domain of the α subunit, and the top of the β subunit of RGD-dependent integrins. Three spots were close enough from each other on the integrin surface to form an extended binding site that could interact with heparin/heparan sulfate chains. Because heparin does not bind to the same integrin site as protein ligands, no steric hindrance prevents the formation of ternary complexes comprising the integrin, its protein ligand, and heparin/heparan sulfate. The basic amino acid residues predicted to interact with heparin are conserved in the sequences of RGD-dependent but not of RGD-independent integrins suggesting that heparin/heparan sulfate could bind to different sites on these two integrin subfamilies.
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Affiliation(s)
- Lionel Ballut
- UMR 5086 CNRS-Université Lyon 1, Institut de Biologie et Chimie des Protéines, 7 passage du Vercors, 69367 Lyon Cedex 07, France
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Roddick LA, Bhakta V, Sheffield WP. Fusion of the C-terminal triskaidecapeptide of hirudin variant 3 to alpha1-proteinase inhibitor M358R increases the serpin-mediated rate of thrombin inhibition. BMC BIOCHEMISTRY 2013; 14:31. [PMID: 24215622 PMCID: PMC3830444 DOI: 10.1186/1471-2091-14-31] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Accepted: 11/05/2013] [Indexed: 11/10/2022]
Abstract
BACKGROUND Alpha-1 proteinase inhibitor (API) is a plasma serpin superfamily member that inhibits neutrophil elastase; variant API M358R inhibits thrombin and activated protein C (APC). Fusing residues 1-75 of another serpin, heparin cofactor II (HCII), to API M358R (in HAPI M358R) was previously shown to accelerate thrombin inhibition over API M358R by conferring thrombin exosite 1 binding properties. We hypothesized that replacing HCII 1-75 region with the 13 C-terminal residues (triskaidecapeptide) of hirudin variant 3 (HV354-66) would further enhance the inhibitory potency of API M358R fusion proteins. We therefore expressed HV3API M358R (HV354-66 fused to API M358R) and HV3API RCL5 (HV354-66 fused to API F352A/L353V/E354V/A355I/I356A/I460L/M358R) API M358R) as N-terminally hexahistidine-tagged polypeptides in E. coli. RESULTS HV3API M358R inhibited thrombin 3.3-fold more rapidly than API M358R; for HV3API RCL5 the rate enhancement was 1.9-fold versus API RCL5; neither protein inhibited thrombin as rapidly as HAPI M358R. While the thrombin/Activated Protein C rate constant ratio was 77-fold higher for HV3API RCL5 than for HV3API M358R, most of the increased specificity derived from the API F352A/L353V/E354V/A355I/I356A/I460L API RCL 5 mutations, since API RCL5 remained 3-fold more specific than HV3API RCL5. An HV3 54-66 peptide doubled the Thrombin Clotting Time (TCT) and halved the binding of thrombin to immobilized HCII 1-75 at lower concentrations than free HCII 1-75. HV3API RCL5 bound active site-inhibited FPR-chloromethyl ketone-thrombin more effectively than HAPI RCL5. Transferring the position of the fused HV3 triskaidecapeptide to the C-terminus of API M358R decreased the rate of thrombin inhibition relative to that mediated by HV3API M358R by 11-to 14-fold. CONCLUSIONS Fusing the C-terminal triskaidecapeptide of HV3 to API M358R-containing serpins significantly increased their effectiveness as thrombin inhibitors, but the enhancement was less than that seen in HCII 1-75-API M358R fusion proteins. HCII 1-75 was a superior fusion partner, in spite of the greater affinity of the HV3 triskaidecapeptide, manifested both in isolated and API-fused form, for thrombin exosite 1. Our results suggest that HCII 1-75 binds thrombin exosite 1 and orients the attached serpin scaffold for more efficient interaction with the active site of thrombin than the HV3 triskaidecapeptide.
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Affiliation(s)
| | | | - William P Sheffield
- Pathology and Molecular Medicine, McMaster University, 1280 Main Street West, Hamilton, ON L8S 4 K1, Canada.
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50
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Abstract
Thrombin is the central protease in the blood coagulation network. It has multiple substrates and cofactors, and it appears that four serpins are responsible for inhibiting the thrombin produced in haemostasis and thrombosis. Structural studies conducted over the last 10 years have resolved how thrombin recognises these serpins with the aid of cofactors. Although antithrombin (AT), protein C inhibitor (PCI), heparin cofactor II (HCII) and protease nexin-1 (PN1) all share a common fold and mechanism of protease inhibition, they have evolved radically different mechanisms for cofactor-assisted thrombin recognition. This is likely to be due to the varied environments in which thrombin is found. In this review, I discuss the unusual structural features of thrombin that are involved in substrate and cofactor recognition, the serpin mechanism of protease inhibition and the fate of thrombin in the complex, and how the four thrombin-specific serpins exploit the special features of thrombin to accelerate complex formation.
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Affiliation(s)
- J A Huntington
- Department of Haematology, University of Cambridge, Cambridge Institute for Medical Research, Cambridge, UK.
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