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Gujjarlapudi M, Kotarya B, Mohanraj SS, Gupta D, Prasad ER, Kalle AM, Jaba J, Ponnusamy D, Padmasree K. Development of a rapid process for purification of Bowman-Birk and Kunitz inhibitors from legume seeds, and evaluation of their biophysical, insecticidal, and antimicrobial properties. Int J Biol Macromol 2023; 238:124050. [PMID: 36933601 DOI: 10.1016/j.ijbiomac.2023.124050] [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: 01/03/2023] [Revised: 03/02/2023] [Accepted: 03/12/2023] [Indexed: 03/18/2023]
Abstract
Bowman-Birk inhibitor (BBI ~10 kDa) and Kunitz inhibitor (KI ~20 kDa) are serine protease/proteinase inhibitor(s) [PI(s)] ubiquitously found in several Leguminous plant species with insecticidal and therapeutic properties. Due to narrow molecular mass differences, the separation of these inhibitors from a single seed variety is tedious. The present study is aimed to develop a rapid protocol (<24 h) for purifying BBI and KI from legume seeds using mild trichloroacetic acid (TCA) extraction followed by trypsin-affinity chromatography. The mature seeds of Vigna radiata and Cajanus platycarpus are used as a model to purify BBI and KI using this protocol. The BBI and KI purified from the seeds of V. radiata are labeled as VrBBI & VrKI, and C. platycarpus are labeled as CpBBI & CpKI, respectively. These PIs are confirmed by immunodetection and MALDI-TOF studies and further characterized for their structural (CD & fluorescence spectroscopy) and functional properties (temperature & DTT stability). BBI(s) purified using the above process are effective in the management of castor semi-looper 'Achaea janata', while KI(s) are effective in the management of pod borer 'Helicoverpa armigera'. Besides, both BBI(s) and KI(s) have significant potential in controlling the growth of methicillin-sensitive 'Staphylococcus aureus', a gram-positive pathogenic bacterium.
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Affiliation(s)
- Mariyamma Gujjarlapudi
- Department of Biotechnology and Bioinformatics, University of Hyderabad, Hyderabad 500 046, India
| | - Bharti Kotarya
- Department of Biotechnology and Bioinformatics, University of Hyderabad, Hyderabad 500 046, India
| | | | - Deepali Gupta
- Department of Biotechnology and Bioinformatics, University of Hyderabad, Hyderabad 500 046, India
| | - Elaprolu R Prasad
- Department of Plant Sciences, University of Hyderabad, Hyderabad 500 046, India
| | - Arunasree M Kalle
- Department of Animal Biology, University of Hyderabad, Hyderabad 500 046, India
| | - Jagdish Jaba
- Entomology, International Crops Research Institute for the Semi-Arid Tropics, Hyderabad 502 324, India
| | - Duraimurugan Ponnusamy
- Crop Protection Section, ICAR-Indian Institute of Oilseeds Research, Hyderabad 500 030, India
| | - Kollipara Padmasree
- Department of Biotechnology and Bioinformatics, University of Hyderabad, Hyderabad 500 046, India.
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2
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Miniproteins in medicinal chemistry. Bioorg Med Chem Lett 2022; 71:128806. [PMID: 35660515 DOI: 10.1016/j.bmcl.2022.128806] [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: 01/31/2022] [Revised: 05/11/2022] [Accepted: 05/16/2022] [Indexed: 11/20/2022]
Abstract
Miniproteins exhibit great potential as scaffolds for drug candidates because of their well-defined structure and good synthetic availability. Because of recently described methodologies for their de novo design, the field of miniproteins is emerging and can provide molecules that effectively bind to problematic targets, i.e., those that have been previously considered to be undruggable. This review describes methodologies for the development of miniprotein scaffolds and for the construction of biologically active miniproteins.
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3
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Lavergne M, Guillon-Munos A, Lenga Ma Bonda W, Attucci S, Kryza T, Barascu A, Moreau T, Petit-Courty A, Sizaret D, Courty Y, Iochmann S, Reverdiau P. Tissue factor pathway inhibitor 2 is a potent kallikrein-related protease 12 inhibitor. Biol Chem 2021; 402:1257-1268. [PMID: 33977679 DOI: 10.1515/hsz-2020-0389] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 04/30/2021] [Indexed: 11/15/2022]
Abstract
The protease activities are tightly regulated by inhibitors and dysregulation contribute to pathological processes such as cancer and inflammatory disorders. Tissue factor pathway inhibitor 2 (TFPI-2) is a serine proteases inhibitor, that mainly inhibits plasmin. This protease activated matrix metalloproteases (MMPs) and degraded extracellular matrix. Other serine proteases are implicated in these mechanisms like kallikreins (KLKs). In this study, we identified for the first time that TFPI-2 is a potent inhibitor of KLK5 and 12. Computer modeling showed that the first Kunitz domain of TFPI-2 could interact with residues of KLK12 near the catalytic triad. Furthermore, like plasmin, KLK12 was able to activate proMMP-1 and -3, with no effect on proMMP-9. Thus, the inhibition of KLK12 by TFPI-2 greatly reduced the cascade activation of these MMPs and the cleavage of cysteine-rich 61, a matrix signaling protein. Moreover, when TFPI-2 bound to extracellular matrix, its classical localisation, the KLK12 inhibition was retained. Finally, TFPI-2 was downregulated in human non-small-cell lung tumour tissue as compared with non-affected lung tissue. These data suggest that TFPI-2 is a potent inhibitor of KLK12 and could regulate matrix remodeling and cancer progression mediated by KLK12.
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Affiliation(s)
- Marion Lavergne
- Université de Tours, F-37032Tours, France.,INSERM, Centre d'Etude des Pathologies Respiratoires (CEPR), UMR 1100, 10 boulevard Tonnellé, F-37032Tours, France
| | - Audrey Guillon-Munos
- INSERM, Centre d'Etude des Pathologies Respiratoires (CEPR), UMR 1100, 10 boulevard Tonnellé, F-37032Tours, France.,Groupe IMT, Bio3 Institute, 15 rue du Plat D'Etain, F-37020Tours Cedex 1, France
| | - Woodys Lenga Ma Bonda
- Université de Tours, F-37032Tours, France.,INSERM, Centre d'Etude des Pathologies Respiratoires (CEPR), UMR 1100, 10 boulevard Tonnellé, F-37032Tours, France
| | - Sylvie Attucci
- Université de Tours, F-37032Tours, France.,INSERM, Imagerie et Cerveau (iBrain), UMR 1253, F-37000Tours, France
| | - Thomas Kryza
- INSERM, Centre d'Etude des Pathologies Respiratoires (CEPR), UMR 1100, 10 boulevard Tonnellé, F-37032Tours, France.,Mater Research Institute, The University of Queensland, Woollongabba Brisbane, QLD, Australia
| | - Aurélia Barascu
- INSERM, Centre d'Etude des Pathologies Respiratoires (CEPR), UMR 1100, 10 boulevard Tonnellé, F-37032Tours, France.,UMR 8226-CNRS/UPMC, Institut de Biologie Physico-chimique, Sorbonne Université, 13 rue Pierre et Marie Curie, F-75005Paris, France
| | - Thierry Moreau
- Université de Tours, F-37032Tours, France.,INRA, UMR INRA 0083 - Biologie des Oiseaux et Aviculture (BOA), F-37380Nouzilly, France
| | - Agnès Petit-Courty
- Université de Tours, F-37032Tours, France.,INSERM, Centre d'Etude des Pathologies Respiratoires (CEPR), UMR 1100, 10 boulevard Tonnellé, F-37032Tours, France
| | - Damien Sizaret
- Département d'Anatomie et Cytologie Pathologiques, Hôpital Trousseau, CHRU de Tours, F-37044Tours, France
| | - Yves Courty
- INSERM, Centre d'Etude des Pathologies Respiratoires (CEPR), UMR 1100, 10 boulevard Tonnellé, F-37032Tours, France
| | - Sophie Iochmann
- Université de Tours, F-37032Tours, France.,INSERM, Centre d'Etude des Pathologies Respiratoires (CEPR), UMR 1100, 10 boulevard Tonnellé, F-37032Tours, France.,Institut Universitaire de Technologie, F-37082Tours, France
| | - Pascale Reverdiau
- Université de Tours, F-37032Tours, France.,INSERM, Centre d'Etude des Pathologies Respiratoires (CEPR), UMR 1100, 10 boulevard Tonnellé, F-37032Tours, France.,Institut Universitaire de Technologie, F-37082Tours, France
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4
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Vadivel K, Zaiss AK, Kumar Y, Fabian FM, Ismail AEA, Arbing MA, Buchholz WG, Velander WH, Bajaj SP. Enhanced Antifibrinolytic Efficacy of a Plasmin-Specific Kunitz-Inhibitor (60-Residue Y11T/L17R with C-Terminal IEK) of Human Tissue Factor Pathway Inhibitor Type-2 Domain1. J Clin Med 2020; 9:E3684. [PMID: 33212896 PMCID: PMC7698382 DOI: 10.3390/jcm9113684] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Accepted: 10/21/2020] [Indexed: 12/13/2022] Open
Abstract
Current antifibrinolytic agents reduce blood loss by inhibiting plasmin active sites (e.g., aprotinin) or by preventing plasminogen/tissue plasminogen activator (tPA) binding to fibrin clots (e.g., ε-aminocaproic acid and tranexamic acid); however, they have adverse side effects. Here, we expressed 60-residue (NH2NAE…IEKCOOH) Kunitz domain1 (KD1) mutants of human tissue factor pathway inhibitor type-2 that inhibit plasmin as well as plasminogen activation. A single (KD1-L17R-KCOOH) and a double mutant (KD1-Y11T/L17R- KCOOH) were expressed in Escherichia coli as His-tagged constructs, each with enterokinase cleavage sites. KD1-Y11T/L17R-KCOOH was also expressed in Pichia pastoris. KD1-Y11T/L17R-KCOOH inhibited plasmin comparably to aprotinin and bound to the kringle domains of plasminogen/plasmin and tPA with Kd of ~50 nM and ~35 nM, respectively. Importantly, compared to aprotinin, KD1-L17R-KCOOH and KD1-Y11T/L17R-KCOOH did not inhibit kallikrein. Moreover, the antifibrinolytic potential of KD1-Y11T/L17R-KCOOH was better than that of KD1-L17R-KCOOH and similar to that of aprotinin in plasma clot-lysis assays. In thromboelastography experiments, KD1-Y11T/L17R-KCOOH was shown to inhibit fibrinolysis in a dose dependent manner and was comparable to aprotinin at a higher concentration. Further, KD1-Y11T/L17R-KCOOH did not induce cytotoxicity in primary human endothelial cells or fibroblasts. We conclude that KD1-Y11T/L17R-KCOOH is comparable to aprotinin, the most potent known inhibitor of plasmin and can be produced in large amounts using Pichia.
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Affiliation(s)
- Kanagasabai Vadivel
- Department of Orthopedic Surgery, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA; (K.V.); (A.K.Z.); (Y.K.)
| | - Anne K. Zaiss
- Department of Orthopedic Surgery, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA; (K.V.); (A.K.Z.); (Y.K.)
| | - Yogesh Kumar
- Department of Orthopedic Surgery, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA; (K.V.); (A.K.Z.); (Y.K.)
| | - Frank M. Fabian
- Department of Chemical and Biomolecular Engineering, University of Nebraska, Lincoln, NE 68588, USA; (F.M.F.); (A.E.A.I.); (W.G.B.); (W.H.V.)
- Chemistry Department, Walla Walla University, College Place, WA 99324, USA
| | - Ayman E. A. Ismail
- Department of Chemical and Biomolecular Engineering, University of Nebraska, Lincoln, NE 68588, USA; (F.M.F.); (A.E.A.I.); (W.G.B.); (W.H.V.)
| | - Mark A. Arbing
- Protein Expression Technology Center, UCLA-DOE Institute, University of California, Los Angeles, CA 90095, USA;
| | - Wallace G. Buchholz
- Department of Chemical and Biomolecular Engineering, University of Nebraska, Lincoln, NE 68588, USA; (F.M.F.); (A.E.A.I.); (W.G.B.); (W.H.V.)
| | - William H. Velander
- Department of Chemical and Biomolecular Engineering, University of Nebraska, Lincoln, NE 68588, USA; (F.M.F.); (A.E.A.I.); (W.G.B.); (W.H.V.)
| | - S. Paul Bajaj
- Department of Orthopedic Surgery, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA; (K.V.); (A.K.Z.); (Y.K.)
- Molecular Biology Institute, University of California, Los Angeles, CA 90095, USA
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5
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Saikhedkar NS, Joshi RS, Yadav AK, Seal S, Fernandes M, Giri AP. Phyto-inspired cyclic peptides derived from plant Pin-II type protease inhibitor reactive center loops for crop protection from insect pests. Biochim Biophys Acta Gen Subj 2019; 1863:1254-1262. [DOI: 10.1016/j.bbagen.2019.05.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 04/25/2019] [Accepted: 05/06/2019] [Indexed: 01/10/2023]
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6
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Yu X, Yang YP, Dikici E, Deo SK, Daunert S. Beyond Antibodies as Binding Partners: The Role of Antibody Mimetics in Bioanalysis. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2017; 10:293-320. [PMID: 28375702 PMCID: PMC5895458 DOI: 10.1146/annurev-anchem-061516-045205] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The emergence of novel binding proteins or antibody mimetics capable of binding to ligand analytes in a manner analogous to that of the antigen-antibody interaction has spurred increased interest in the biotechnology and bioanalytical communities. The goal is to produce antibody mimetics designed to outperform antibodies with regard to binding affinities, cellular and tumor penetration, large-scale production, and temperature and pH stability. The generation of antibody mimetics with tailored characteristics involves the identification of a naturally occurring protein scaffold as a template that binds to a desired ligand. This scaffold is then engineered to create a superior binder by first creating a library that is then subjected to a series of selection steps. Antibody mimetics have been successfully used in the development of binding assays for the detection of analytes in biological samples, as well as in separation methods, cancer therapy, targeted drug delivery, and in vivo imaging. This review describes recent advances in the field of antibody mimetics and their applications in bioanalytical chemistry, specifically in diagnostics and other analytical methods.
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Affiliation(s)
- Xiaowen Yu
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida 33136;
| | - Yu-Ping Yang
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida 33136;
| | - Emre Dikici
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida 33136;
| | - Sapna K Deo
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida 33136;
| | - Sylvia Daunert
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida 33136;
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7
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Zhang H, Qiao R, Gong H, Cao J, Zhou Y, Zhou J. Identification and anticoagulant activity of a novel Kunitz-type protein HA11 from the salivary gland of the tick Hyalomma asiaticum. EXPERIMENTAL & APPLIED ACAROLOGY 2017; 71:71-85. [PMID: 28091958 DOI: 10.1007/s10493-017-0106-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Accepted: 01/07/2017] [Indexed: 05/16/2023]
Abstract
Kunitz/bovine pancreatic trypsin inhibitor proteins are abundant in the salivary glands of ticks and perform multiple functions in blood feeding, including inhibiting blood coagulation, regulating host blood supply and disrupting host angiogenesis. In this study, we identified a novel gene designated HA11 (Hyalomma asiaticum 11 kDa protein) from the salivary gland of the tick H. asiaticum. HA11 is encoded by a gene with an open reading frame of 306 bp that is translated into a deduced 101 amino acid 11 kDa protein that shares 27% sequence identity with a Kunitz-like protease inhibitor precursor in Amblyomma variegatum. Bioinformatic analysis confirmed HA11 as a member of the Kunitz-type family of inhibitors. Real time-PCR detected HA11 mRNA transcripts in tick larvae and nymphae stages, with levels highest in salivary gland tissue, and transcription was induced by blood feeding. HA11 anticoagulant activity was demonstrated by its ability to delay normal clotting of rabbit plasma in an activated partial thromboplastin time assay. Furthermore, RNA interference confirmed that HA11 influences H. asiaticum development and blood feeding, and the recombinant protein exerted low hemolytic activity. These results suggest HA11 is a novel Kunitz-type anticoagulant protein involved in tick blood feeding that may have potential as an anticoagulant drug or vaccine.
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Affiliation(s)
- Houshuang Zhang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518 Ziyue Road, Minhang District, Shanghai, 200241, China
| | - Ruiqiong Qiao
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518 Ziyue Road, Minhang District, Shanghai, 200241, China
| | - Haiyan Gong
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518 Ziyue Road, Minhang District, Shanghai, 200241, China
| | - Jie Cao
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518 Ziyue Road, Minhang District, Shanghai, 200241, China
| | - Yongzhi Zhou
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518 Ziyue Road, Minhang District, Shanghai, 200241, China
| | - Jinlin Zhou
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518 Ziyue Road, Minhang District, Shanghai, 200241, China.
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, China.
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8
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Vadivel K, Kumar Y, Ogueli GI, Ponnuraj SM, Wongkongkathep P, Loo JA, Bajaj MS, Bajaj SP. S2'-subsite variations between human and mouse enzymes (plasmin, factor XIa, kallikrein) elucidate inhibition differences by tissue factor pathway inhibitor -2 domain1-wild-type, Leu17Arg-mutant and aprotinin. J Thromb Haemost 2016; 14:2509-2523. [PMID: 27797450 PMCID: PMC5504414 DOI: 10.1111/jth.13538] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Indexed: 12/20/2022]
Abstract
Essentials Current antifibrinolytics - aminocaproic acid and tranexamic acid-can cause seizures or renal injury. KD1L17R -KT , aprotinin and tranexamic acid were tested in a modified mouse tail-amputation model. S2'-subsite variations between human and mouse factor XIa result in vastly different inhibition profiles. KD1L17R -KT reduces blood loss and D-dimer levels in mouse with unobserved seizures or renal injury. SUMMARY Background Using tissue factor pathway inhibitor (TFPI)-2 Kunitz domain1 (KD1), we obtained a bifunctional antifibrinolytic molecule (KD1L17R -KT ) with C-terminal lysine (kringle domain binding) and P2'-residue arginine (improved specificity towards plasmin). KD1L17R -KT strongly inhibited human plasmin (hPm), with no inhibition of human kallikrein (hKLK) or factor XIa (hXIa). Furthermore, KD1L17R -KT reduced blood loss comparable to aprotinin in a mouse liver-laceration model of organ hemorrhage. However, effectiveness of these antifibrinolytic agents in a model of hemorrhage mimicking extremity trauma and their inhibition efficiencies for mouse enzymes (mPm, mKLK or mXIa) remain to be determined. Objective To determine potential differences in inhibition constants of various antifibrinolytic agents against mouse and human enzymes and test their effectiveness in a modified mouse tail-amputation hemorrhage model. Methods/Results Unexpectedly, mXIa was inhibited with ~ 17-fold increased affinity by aprotinin (Ki ~ 20 nm) and with measurable affinity for KD1L17R -KT (Ki ~ 3 μm); in contrast, KD1WT -VT inhibited hXIa or mXIa with similar affinity. Compared with hPm, mPm had ~ 3-fold reduced affinity, whereas species specificity for hKLK and mKLK was comparable for each inhibitor. S2'-subsite variations largely accounted for the observed differences. KD1L17R -KT and aprotinin were more effective than KD1WT -VT or tranexamic acid in inhibiting tPA-induced mouse plasma clot lysis. Further, KD1L17R -KT was more effective than KD1WT -VT and was comparable to aprotinin and tranexamic acid in reducing blood loss and D-dimer levels in the mouse tail-amputation model. Conclusions Inhibitor potencies differ between antifibrinolytic agents against human and mouse enzymes. KD1L17R -KT is effective in reducing blood loss in a tail-amputation model that mimics extremity injury.
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Affiliation(s)
- K Vadivel
- Department of Orthopaedic Surgery, University of California, Los Angeles, CA, USA
| | - Y Kumar
- Department of Orthopaedic Surgery, University of California, Los Angeles, CA, USA
| | - G I Ogueli
- Department of Orthopaedic Surgery, University of California, Los Angeles, CA, USA
| | - S M Ponnuraj
- Department of Orthopaedic Surgery, University of California, Los Angeles, CA, USA
| | - P Wongkongkathep
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
| | - J A Loo
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
- Molecular Biology Institute, University of California, Los Angeles, CA, USA
| | - M S Bajaj
- Division of Pulmonology and Critical Care, Department of Medicine, University of California, Los Angeles, CA, USA
| | - S P Bajaj
- Department of Orthopaedic Surgery, University of California, Los Angeles, CA, USA
- Molecular Biology Institute, University of California, Los Angeles, CA, USA
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9
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Sangsuriya P, Charoensapsri W, Chomwong S, Senapin S, Tassanakajon A, Amparyup P. A shrimp pacifastin light chain-like inhibitor: molecular identification and role in the control of the prophenoloxidase system. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2016; 54:32-45. [PMID: 26271600 DOI: 10.1016/j.dci.2015.08.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 08/05/2015] [Accepted: 08/06/2015] [Indexed: 06/04/2023]
Abstract
Pacifastin is a recently classified family of serine proteinase inhibitors that play essential roles in various biological processes, including in the regulation of the melanization cascade. Here, a novel pacifastin-related gene, termed PmPacifastin-like, was identified from a reverse suppression subtractive hybridization (SSH) cDNA library created from hemocytes of the prophenoloxidase PmproPO1/2 co-silenced black tiger shrimp Penaeus monodon. The full-length sequences of PmPacifastin-like and its homologue LvPacifastin-like from the Pacific white shrimp Litopenaeus vannamei were determined. Sequence analysis revealed that both sequences contained thirteen conserved pacifastin light chain domains (PLDs), followed by two putative kunitz domains. Expression analysis demonstrated that the PmPacifastin-like transcript was expressed in all tested shrimp tissues and larval developmental stages, and its expression responded to Vibrio harveyi challenge. To gain insight into the functional roles of PmPacifastin-like protein, the in vivo RNA interference experiment was employed; the results showed that PmPacifastin-like depletion strongly increased PO activity. Interestingly, suppression of PmPacifastin-like also down-regulated the expression of the proPO-activating enzyme PmPPAE2 transcript; the PmPacifastin-like transcript was down-regulated after the PmproPO1/2 transcripts were silenced. Taken together, these results suggest that PmPacifastin-like is important in the shrimp proPO system and may play an essential role in shrimp immune defense against bacterial infection. These results also expand the knowledge of how pacifastin-related protein participates in the negative regulation of the proPO system in shrimp.
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Affiliation(s)
- Pakkakul Sangsuriya
- Center of Excellence for Molecular Biology and Genomics of Shrimp, Department of Biochemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Bangkok 10330, Thailand; National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), 113 Paholyothin Road, Klong 1, Klong Luang, Pathumthani 12120, Thailand
| | - Walaiporn Charoensapsri
- National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), 113 Paholyothin Road, Klong 1, Klong Luang, Pathumthani 12120, Thailand; Center of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Mahidol University, Rama VI Road, Bangkok 10400, Thailand
| | - Sudarat Chomwong
- Center of Excellence for Molecular Biology and Genomics of Shrimp, Department of Biochemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Bangkok 10330, Thailand; Program of Biotechnology, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Bangkok 10330, Thailand
| | - Saengchan Senapin
- National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), 113 Paholyothin Road, Klong 1, Klong Luang, Pathumthani 12120, Thailand; Center of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Mahidol University, Rama VI Road, Bangkok 10400, Thailand
| | - Anchalee Tassanakajon
- Center of Excellence for Molecular Biology and Genomics of Shrimp, Department of Biochemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Bangkok 10330, Thailand
| | - Piti Amparyup
- Center of Excellence for Molecular Biology and Genomics of Shrimp, Department of Biochemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Bangkok 10330, Thailand; National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), 113 Paholyothin Road, Klong 1, Klong Luang, Pathumthani 12120, Thailand.
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10
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Sudha G, Singh P, Swapna LS, Srinivasan N. Weak conservation of structural features in the interfaces of homologous transient protein-protein complexes. Protein Sci 2015; 24:1856-73. [PMID: 26311309 DOI: 10.1002/pro.2792] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 08/13/2015] [Accepted: 08/17/2015] [Indexed: 12/21/2022]
Abstract
Residue types at the interface of protein-protein complexes (PPCs) are known to be reasonably well conserved. However, we show, using a dataset of known 3-D structures of homologous transient PPCs, that the 3-D location of interfacial residues and their interaction patterns are only moderately and poorly conserved, respectively. Another surprising observation is that a residue at the interface that is conserved is not necessarily in the interface in the homolog. Such differences in homologous complexes are manifested by substitution of the residues that are spatially proximal to the conserved residue and structural differences at the interfaces as well as differences in spatial orientations of the interacting proteins. Conservation of interface location and the interaction pattern at the core of the interfaces is higher than at the periphery of the interface patch. Extents of variability of various structural features reported here for homologous transient PPCs are higher than the variation in homologous permanent homomers. Our findings suggest that straightforward extrapolation of interfacial nature and inter-residue interaction patterns from template to target could lead to serious errors in the modeled complex structure. Understanding the evolution of interfaces provides insights to improve comparative modeling of PPC structures.
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Affiliation(s)
- Govindarajan Sudha
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, 560012, Karnataka, India
| | - Prashant Singh
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, 560012, Karnataka, India
| | - Lakshmipuram S Swapna
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, 560012, Karnataka, India
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11
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García-Fernández R, Perbandt M, Rehders D, Ziegelmüller P, Piganeau N, Hahn U, Betzel C, Chávez MDLÁ, Redecke L. Three-dimensional Structure of a Kunitz-type Inhibitor in Complex with an Elastase-like Enzyme. J Biol Chem 2015; 290:14154-65. [PMID: 25878249 DOI: 10.1074/jbc.m115.647586] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Indexed: 11/06/2022] Open
Abstract
Elastase-like enzymes are involved in important diseases such as acute pancreatitis, chronic inflammatory lung diseases, and cancer. Structural insights into their interaction with specific inhibitors will contribute to the development of novel anti-elastase compounds that resist rapid oxidation and proteolysis. Proteinaceous Kunitz-type inhibitors homologous to the bovine pancreatic trypsin inhibitor (BPTI) provide a suitable scaffold, but the structural aspects of their interaction with elastase-like enzymes have not been elucidated. Here, we increased the selectivity of ShPI-1, a versatile serine protease inhibitor from the sea anemone Stichodactyla helianthus with high biomedical and biotechnological potential, toward elastase-like enzymes by substitution of the P1 residue (Lys(13)) with leucine. The variant (rShPI-1/K13L) exhibits a novel anti-porcine pancreatic elastase (PPE) activity together with a significantly improved inhibition of human neuthrophil elastase and chymotrypsin. The crystal structure of the PPE·rShPI-1/K13L complex determined at 2.0 Å resolution provided the first details of the canonical interaction between a BPTI-Kunitz-type domain and elastase-like enzymes. In addition to the essential impact of the variant P1 residue for complex stability, the interface is improved by increased contributions of the primary and secondary binding loop as compared with similar trypsin and chymotrypsin complexes. A comparison of the interaction network with elastase complexes of canonical inhibitors from the chelonian in family supports a key role of the P3 site in ShPI-1 in directing its selectivity against pancreatic and neutrophil elastases. Our results provide the structural basis for site-specific mutagenesis to further improve the binding affinity and/or direct the selectivity of BPTI-Kunitz-type inhibitors toward elastase-like enzymes.
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Affiliation(s)
- Rossana García-Fernández
- From the Centro de Estudio de Proteínas, Facultad de Biología, Universidad de la Habana, 20146 Habana, Cuba
| | - Markus Perbandt
- the Institute of Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, 22761 Hamburg, Germany, the Hamburg Centre for Ultrafast Imaging, 22761 Hamburg, Germany, and
| | - Dirk Rehders
- the Joint Laboratory for Structural Biology of Infection and Inflammation, Institute of Biochemistry and Molecular Biology, University of Hamburg, 20146 Hamburg, Germany, and Institute of Biochemistry, University of Lübeck, c/o Deutsches Elektronen Synchrotron (DESY), 22603 Hamburg, Germany
| | - Patrick Ziegelmüller
- the Institute of Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, 22761 Hamburg, Germany
| | - Nicolas Piganeau
- the Institute of Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, 22761 Hamburg, Germany
| | - Ulrich Hahn
- the Institute of Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, 22761 Hamburg, Germany
| | - Christian Betzel
- the Institute of Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, 22761 Hamburg, Germany
| | | | - Lars Redecke
- the Joint Laboratory for Structural Biology of Infection and Inflammation, Institute of Biochemistry and Molecular Biology, University of Hamburg, 20146 Hamburg, Germany, and Institute of Biochemistry, University of Lübeck, c/o Deutsches Elektronen Synchrotron (DESY), 22603 Hamburg, Germany
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12
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Kumar Y, Vadivel K, Schmidt AE, Ogueli GI, Ponnuraj SM, Rannulu N, Loo JA, Bajaj M, Bajaj SP. Decoy plasminogen receptor containing a selective Kunitz-inhibitory domain. Biochemistry 2014; 53:505-17. [PMID: 24383758 PMCID: PMC3985851 DOI: 10.1021/bi401584b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 12/31/2013] [Indexed: 11/29/2022]
Abstract
Kunitz domain 1 (KD1) of tissue factor pathway inhibitor-2 in which P2' residue Leu17 (bovine pancreatic trypsin inhibitor numbering) is mutated to Arg selectively inhibits the active site of plasmin with ∼5-fold improved affinity. Thrombin cleavage (24 h extended incubation at a 1:50 enzyme-to-substrate ratio) of the KD1 mutant (Leu17Arg) yielded a smaller molecule containing the intact Kunitz domain with no detectable change in the active-site inhibitory function. The N-terminal sequencing and MALDI-TOF/ESI data revealed that the starting molecule has a C-terminal valine (KD1L17R-VT), whereas the smaller molecule has a C-terminal lysine (KD1L17R-KT). Because KD1L17R-KT has C-terminal lysine, we examined whether it could serve as a decoy receptor for plasminogen/plasmin. Such a molecule might inhibit plasminogen activation as well as the active site of generated plasmin. In surface plasmon resonance experiments, tissue plasminogen activator (tPA) and Glu-plasminogen bound to KD1L17R-KT (Kd ∼ 0.2 to 0.3 μM) but not to KD1L17R-VT. Furthermore, KD1L17R-KT inhibited tPA-induced plasma clot fibrinolysis more efficiently than KD1L17R-VT. Additionally, compared to ε-aminocaproic acid KD1L17R-KT was more effective in reducing blood loss in a mouse liver-laceration injury model, where the fibrinolytic system is activated. In further experiments, the micro(μ)-plasmin-KD1L17R-KT complex inhibited urokinase-induced plasminogen activation on phorbol-12-myristate-13-acetate-stimulated U937 monocyte-like cells, whereas the μ-plasmin-KD1L17R-VT complex failed to inhibit this process. In conclusion, KD1L17R-KT inhibits the active site of plasmin as well as acts as a decoy receptor for the kringle domain(s) of plasminogen/plasmin; hence, it limits both plasmin generation and activity. With its dual function, KD1L17R-KT could serve as a preferred agent for controlling plasminogen activation in pathological processes.
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Affiliation(s)
- Yogesh Kumar
- Department
of Orthopaedic Surgery, UCLA School of Medicine, Los Angeles, California 90095, United States
| | - Kanagasabai Vadivel
- Department
of Orthopaedic Surgery, UCLA School of Medicine, Los Angeles, California 90095, United States
| | - Amy E. Schmidt
- Department
of Pathology and Laboratory Medicine, Indiana
University School of Medicine, Indianapolis, Indiana 46202, United States
| | - Godwin I. Ogueli
- Department
of Orthopaedic Surgery, UCLA School of Medicine, Los Angeles, California 90095, United States
| | - Sathya M. Ponnuraj
- Department
of Orthopaedic Surgery, UCLA School of Medicine, Los Angeles, California 90095, United States
| | - Nalaka Rannulu
- Department
of Chemistry and Biochemistry, UCLA, Los Angeles, California 90095, United States
| | - Joseph A. Loo
- Department
of Chemistry and Biochemistry, UCLA, Los Angeles, California 90095, United States
- Molecular
Biology Institute, UCLA, Los Angeles, California 90095, United States
| | - Madhu
S. Bajaj
- Department
of Medicine, Division of Pulmonary, and Critical Care Medicine, David
Geffen School of Medicine, UCLA, Los Angeles, California 90095, United States
| | - S. Paul Bajaj
- Department
of Orthopaedic Surgery, UCLA School of Medicine, Los Angeles, California 90095, United States
- Molecular
Biology Institute, UCLA, Los Angeles, California 90095, United States
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13
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Morais KLP, Pasqualoto KFM, Pacheco MTF, Berra CM, Alvarez-Flores MP, Chudzinski-Tavassi AM. Rational development of a novel TFPI-like inhibitor fromAmblyomma cajennensetick. TOXIN REV 2013. [DOI: 10.3109/15569543.2013.845217] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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14
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Durani V, Magliery TJ. Protein engineering and stabilization from sequence statistics: variation and covariation analysis. Methods Enzymol 2013; 523:237-56. [PMID: 23422433 DOI: 10.1016/b978-0-12-394292-0.00011-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The concepts of consensus and correlation in multiple sequence alignments (MSAs) have been used in the past to understand and engineer proteins. However, there are multiple ways of acquiring MSA databases and also numerous mathematical metrics that can be applied to calculate each of the parameters. This chapter describes an overall methodology that we have chosen to employ for acquiring and statistically analyzing MSAs. We have provided a step-by-step protocol for calculating relative entropy and mutual information metrics and describe how they can be used to predict mutations that have a high probability of stabilizing a protein. This protocol allows for flexibility for modification of formulae and parameters without using anything more complicated than Microsoft Excel. We have also demonstrated various aspects of data analysis by carrying out a sample analysis on the BPTI-Kunitz family of proteins and identified mutations that would be predicted to stabilize this protein based on consensus and correlation values.
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Affiliation(s)
- Venuka Durani
- Department of Chemistry, The Ohio State University, Columbus, Ohio, USA
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15
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García-Fernández R, Pons T, Perbandt M, Valiente PA, Talavera A, González-González Y, Rehders D, Chávez MA, Betzel C, Redecke L. Structural insights into serine protease inhibition by a marine invertebrate BPTI Kunitz-type inhibitor. J Struct Biol 2012; 180:271-9. [PMID: 22975140 DOI: 10.1016/j.jsb.2012.08.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Revised: 08/22/2012] [Accepted: 08/24/2012] [Indexed: 10/27/2022]
Abstract
Proteins isolated from marine invertebrates are frequently characterized by exceptional structural and functional properties. ShPI-1, a BPTI Kunitz-type inhibitor from the Caribbean Sea anemone Stichodactyla helianthus, displays activity not only against serine-, but also against cysteine-, and aspartate proteases. As an initial step to evaluate the molecular basis of its activities, we describe the crystallographic structure of ShPI-1 in complex with the serine protease bovine pancreatic trypsin at 1.7Å resolution. The overall structure and the important enzyme-inhibitor interactions of this first invertebrate BPTI-like Kunitz-type inhibitor:trypsin complex remained largely conserved compared to mammalian BPTI-Kunitz inhibitor complexes. However, a prominent stabilizing role within the interface was attributed to arginine at position P3. Binding free-energy calculations indicated a 10-fold decrease for the inhibitor affinity against trypsin, if the P3 residue of ShPI-1 is mutated to alanine. Together with the increased role of Arg(11) at P3 position, slightly reduced interactions at the prime side (Pn') of the primary binding loop and at the secondary binding loop of ShPI-1 were detected. In addition, the structure provides important information for site directed mutagenesis to further optimize the activity of rShPI-1A for biotechnological applications.
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Affiliation(s)
- Rossana García-Fernández
- Centro de Estudio de Proteínas, Facultad de Biología, Universidad de la Habana, Calle 25 No 411, Havana, Cuba
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16
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Iriarte A, Arbildi P, La-Rocca S, Musto H, Fernández V. Identification of novel glutathione transferases in Echinococcus granulosus. An evolutionary perspective. Acta Trop 2012; 123:208-16. [PMID: 22659461 DOI: 10.1016/j.actatropica.2012.05.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Revised: 03/28/2012] [Accepted: 05/18/2012] [Indexed: 11/24/2022]
Abstract
Glutathione transferase enzymes (GSTs) constitute a major detoxification system in helminth parasites and have been related to the modulation of host immune response mechanisms. At least three different GSTs classes have been described in Platyhelminthes: Mu, Sigma and Omega. Mining the genome of Echinococcus multilocularis and the ESTs databases of Taenia solium and E. granulosus identified two new GSTs from the cestode E. granulosus, named EgGST2 and EgGST3. It also revealed that the Omega class of GSTs was absent from the Taenidae family. EgGST2 and EgGST3 are actively expressed in the parasite. In order to know the origin of these new GSTs, in silico analyses were performed. While EgGST2 is classified as belonging to the Sigma class, the data obtained for EgGST3 allowed a less clear interpretation. The study of the evolutionary relatedness based on the C-terminal domain sequence, gene structure conservation and three-dimensional structure predictions, suggests that EgGST3 is derived from the Platyhelminthes' Sigma-class cluster. Interestingly, the N-terminal domain displays some characteristic Omega-class residues, including a Cys residue that is likely to be involved in the catalytic mechanism. We discuss different evolutionary scenarios that could explain the observed patterns.
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17
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Majumder S, Khamrui S, Dasgupta J, Dattagupta JK, Sen U. Role of remote scaffolding residues in the inhibitory loop pre-organization, flexibility, rigidification and enzyme inhibition of serine protease inhibitors. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2012; 1824:882-90. [PMID: 22709512 DOI: 10.1016/j.bbapap.2012.04.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2012] [Revised: 04/22/2012] [Accepted: 04/23/2012] [Indexed: 11/27/2022]
Abstract
Canonical serine protease inhibitors interact with cognate enzymes through the P3-P2' region of the inhibitory loop while its scaffold hardly makes any contact. Neighboring scaffolding residues like Arginines or Asparagine shape-up the inhibitory loop and favor the resynthesis of cleaved scissile bond. However, role of remote scaffolding residues, which are not involved in religation, was not properly explored. Crystal structures of two engineered winged bean chymotrypsin inhibitor (WCI) complexed with Bovine trypsin (BPT) namely L65R-WCI:BPT and F64Y/L65R-WCI:BPT show that the inhibitory loop of these engineered inhibitors are recognized and rigidified properly at the enzyme active site like other strong trypsin inhibitors. Chimeric protein ETI(L)-WCI(S), having a loop of Erythrina caffra Trypsin Inhibitor, ETI on the scaffold of WCI, was previously shown to behave like substrate. Non-canonical structure of the inhibitory loop and its flexibility are attributed to the presence of smaller scaffolding residues which cannot act as barrier to the inhibitory loop like in ETI. Double mutant A76R/L115Y-(ETI(L)-WCI(S)), where the barrier is reintroduced on ETI(L)-WCI(S), shows regaining of inhibitory activity. The structure of A76R/L115Y-(ETI(L)-WCI(S)) along with L65R-WCI:BPT and F64Y/L65R-WCI:BPT demonstrate here that the lost canonical conformation of the inhibitory loop is fully restored and loop flexibility is dramatically reduced. Therefore, residues at the inhibitory loop interact with the enzyme playing the primary role in recognition and binding but scaffolding residues having no direct interaction with the enzyme are crucial for rigidification event and the inhibitory potency. B-factor analysis indicates that the amount of inhibitory loop rigidification varies between different inhibitor families.
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Affiliation(s)
- Sudip Majumder
- Crystallography and Molecular Biology Division, Saha Institute of Nuclear Physics, Kolkata, India
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18
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Dai SX, Zhang AD, Huang JF. Evolution, expansion and expression of the Kunitz/BPTI gene family associated with long-term blood feeding in Ixodes Scapularis. BMC Evol Biol 2012; 12:4. [PMID: 22244187 PMCID: PMC3273431 DOI: 10.1186/1471-2148-12-4] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Accepted: 01/14/2012] [Indexed: 01/22/2023] Open
Abstract
Background Recent studies of the tick saliva transcriptome have revealed the profound role of salivary proteins in blood feeding. Kunitz/BPTI proteins are abundant in the salivary glands of ticks and perform multiple functions in blood feeding, such as inhibiting blood coagulation, regulating host blood supply and disrupting host angiogenesis. However, Kunitz/BPTI proteins in soft and hard ticks have different functions and molecular mechanisms. How these differences emerged and whether they are associated with the evolution of long-term blood feeding in hard ticks remain unknown. Results In this study, the evolution, expansion and expression of Kunitz/BPTI family in Ixodes scapularis were investigated. Single- and multi-domain Kunitz/BPTI proteins have similar gene structures. Single-domain proteins were classified into three groups (groups I, II and III) based on their cysteine patterns. Group I represents the ancestral branch of the Kunitz/BPTI family, and members of this group function as serine protease inhibitors. The group I domain was used as a module to create multi-domain proteins in hard ticks after the split between hard and soft ticks. However, groups II and III, which evolved from group I, are only present and expanded in the genus Ixodes. These lineage-specific expanded genes exhibit significantly higher expression during long-term blood feeding in Ixodes scapularis. Interestingly, functional site analysis suggested that group II proteins lost the ability to inhibit serine proteases and evolved a new function of modulating ion channels. Finally, evolutionary analyses revealed that the expansion and diversification of the Kunitz/BPTI family in the genus Ixodes were driven by positive selection. Conclusions These results suggest that the differences in the Kunitz/BPTI family between soft and hard ticks may be linked to the evolution of long-term blood feeding in hard ticks. In Ixodes, the lineage-specific expanded genes (Group II and III) lost the ancient function of inhibiting serine proteases and evolved new functions to adapt to long-term blood feeding. Therefore, these genes may play a profound role in the long-term blood feeding of hard ticks. Based our analysis, we propose that the six genes identified in our study may be candidate target genes for tick control.
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Affiliation(s)
- Shao-Xing Dai
- School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, PR China
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19
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Abstract
Human tissue factor pathway inhibitor-2 (TFPI-2) has been implicated as a metastasis-associated gene in many types of tumors. In this study, we investigated whether TFPI-2 was inactivated epigenetically in pediatric acute myeloid leukemia (AML). Methylation status was investigated by methylation-specific polymerase chain reaction and bisulfate genomic sequencing. TFPI-2 was aberrantly methylated in 50% (3/6) of AML cell lines. Aberrant methylation of TFPI-2 promoter was detected in 71.6% (48/67) of the Chinese pediatric AML patients. TFPI-2 transcript was significantly lower in AML group compared with controls (3.44 vs. 32.8, P<0.001). Patients with methylated TFPI-2 gene had significantly lower TFPI-2 transcript than those patients without methylated TFPI-2 (P=0.04). Promoter hypermethylation of TFPI-2 is frequent and specific event in pediatric AML.
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20
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Abstract
Background Few existing protein-protein interface design methods allow for extensive backbone rearrangements during the design process. There is also a dichotomy between redesign methods, which take advantage of the native interface, and de novo methods, which produce novel binders. Methodology Here, we propose a new method for designing novel protein reagents that combines advantages of redesign and de novo methods and allows for extensive backbone motion. This method requires a bound structure of a target and one of its natural binding partners. A key interaction in this interface, the anchor, is computationally grafted out of the partner and into a surface loop on the design scaffold. The design scaffold's surface is then redesigned with backbone flexibility to create a new binding partner for the target. Careful choice of a scaffold will bring experimentally desirable characteristics into the new complex. The use of an anchor both expedites the design process and ensures that binding proceeds against a known location on the target. The use of surface loops on the scaffold allows for flexible-backbone redesign to properly search conformational space. Conclusions and Significance This protocol was implemented within the Rosetta3 software suite. To demonstrate and evaluate this protocol, we have developed a benchmarking set of structures from the PDB with loop-mediated interfaces. This protocol can recover the correct loop-mediated interface in 15 out of 16 tested structures, using only a single residue as an anchor.
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Affiliation(s)
- Steven M. Lewis
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Brian A. Kuhlman
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- * E-mail:
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21
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Bajaj MS, Ogueli GI, Kumar Y, Vadivel K, Lawson G, Shanker S, Schmidt AE, Bajaj SP. Engineering kunitz domain 1 (KD1) of human tissue factor pathway inhibitor-2 to selectively inhibit fibrinolysis: properties of KD1-L17R variant. J Biol Chem 2010; 286:4329-40. [PMID: 21115497 DOI: 10.1074/jbc.m110.191163] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Tissue factor pathway inhibitor-2 (TFPI-2) inhibits factor XIa, plasma kallikrein, and factor VIIa/tissue factor; accordingly, it has been proposed for use as an anticoagulant. Full-length TFPI-2 or its isolated first Kunitz domain (KD1) also inhibits plasmin; therefore, it has been proposed for use as an antifibrinolytic agent. However, the anticoagulant properties of TFPI-2 or KD1 would diminish its antifibrinolytic function. In this study, structure-based investigations and analysis of the serine protease profiles revealed that coagulation enzymes prefer a hydrophobic residue at the P2' position in their substrates/inhibitors, whereas plasmin prefers a positively charged arginine residue at the corresponding position in its substrates/inhibitors. Based upon this observation, we changed the P2' residue Leu-17 in KD1 to Arg (KD1-L17R) and compared its inhibitory properties with wild-type KD1 (KD1-WT). Both WT and KD1-L17R were expressed in Escherichia coli, folded, and purified to homogeneity. N-terminal sequences and mass spectra confirmed proper expression of KD1-WT and KD1-L17R. Compared with KD1-WT, the KD1-L17R did not inhibit factor XIa, plasma kallikrein, or factor VIIa/tissue factor. Furthermore, KD1-L17R inhibited plasmin with ∼6-fold increased affinity and effectively prevented plasma clot fibrinolysis induced by tissue plasminogen activator. Similarly, in a mouse liver laceration bleeding model, KD1-L17R was ∼8-fold more effective than KD1-WT in preventing blood loss. Importantly, in this bleeding model, KD1-L17R was equally or more effective than aprotinin or tranexamic acid, which have been used as antifibrinolytic agents to prevent blood loss during major surgery/trauma. Furthermore, as compared with aprotinin, renal toxicity was not observed with KD1-L17R.
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Affiliation(s)
- Madhu S Bajaj
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, David Geffen School of Medicine, UCLA, Los Angeles, California 90095, USA
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22
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Anti-inflammatory actions of serine protease inhibitors containing the Kunitz domain. Inflamm Res 2010; 59:679-87. [PMID: 20454830 DOI: 10.1007/s00011-010-0205-5] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2009] [Revised: 02/01/2010] [Accepted: 04/12/2010] [Indexed: 02/07/2023] Open
Abstract
INTRODUCTION Protease inhibitors, including the Kunitz, Kazal, serpin and mucus families, play important roles in inhibiting protease activities during homeostasis, inflammation, tissue injury, and cancer progression. Interestingly, in addition to their anti-protease activity, protease inhibitors also often possess other intrinsic properties that contribute to termination of the inflammatory process, including modulation of cytokine expression, signal transduction and tissue remodeling. In this review we have tried to summarize recent findings on the Kunitz family of serine proteinase inhibitors and their implications in health and disease. MATERIALS AND METHODS A systematic search was performed in the electronic databases PubMed and ScienceDirect up to October 2009. We tried to limit the review to anti-inflammatory actions and actions not related to protease inhibition. RESULTS AND CONCLUSION Recent studies have demonstrated that the Kunitz inhibitors are not only protease inhibitors, but can also prevent inflammation and tissue injury and subsequently promote tissue remodeling.
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23
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Bao R, Zhou CZ, Jiang C, Lin SX, Chi CW, Chen Y. The ternary structure of the double-headed arrowhead protease inhibitor API-A complexed with two trypsins reveals a novel reactive site conformation. J Biol Chem 2009; 284:26676-84. [PMID: 19640842 PMCID: PMC2785355 DOI: 10.1074/jbc.m109.022095] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2009] [Revised: 07/13/2009] [Indexed: 11/06/2022] Open
Abstract
The double-headed arrowhead protease inhibitors API-A and -B from the tubers of Sagittaria sagittifolia (Linn) feature two distinct reactive sites, unlike other members of their family. Although the two inhibitors have been extensively characterized, the identities of the two P1 residues in both API-A and -B remain controversial. The crystal structure of a ternary complex at 2.48 A resolution revealed that the two trypsins bind on opposite sides of API-A and are 34 A apart. The overall fold of API-A belongs to the beta-trefoil fold and resembles that of the soybean Kunitz-type trypsin inhibitors. The two P1 residues were unambiguously assigned as Leu(87) and Lys(145), and their identities were further confirmed by site-directed mutagenesis. Reactive site 1, composed of residues P5 Met(83) to P5' Ala(92), adopts a novel conformation with the Leu(87) completely embedded in the S1 pocket even though it is an unfavorable P1 residue for trypsin. Reactive site 2, consisting of residues P5 Cys(141) to P5' Glu(150), binds trypsin in the classic mode by employing a two-disulfide-bonded loop. Analysis of the two binding interfaces sheds light on atomic details of the inhibitor specificity and also promises potential improvements in enzyme activity by engineering of the reactive sites.
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Affiliation(s)
- Rui Bao
- From the Institute of Protein Research, Tongji University, Shanghai 200092
| | - Cong-Zhao Zhou
- the Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, and
| | - Chunhui Jiang
- From the Institute of Protein Research, Tongji University, Shanghai 200092
| | - Sheng-Xiang Lin
- the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Cheng-Wu Chi
- From the Institute of Protein Research, Tongji University, Shanghai 200092
- the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Yuxing Chen
- the Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, and
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24
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Kempaiah P, Danielson LA, Barry M, Kisiel W. Comparative effects of aprotinin and human recombinant R24K KD1 on temporal renal function in Long-Evans rats. J Pharmacol Exp Ther 2009; 331:940-5. [PMID: 19776384 DOI: 10.1124/jpet.109.161034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Bovine aprotinin, a reversible inhibitor of plasmin and kallikrein, has been clinically approved for over two decades to prevent perioperative blood loss during cardiac surgery. However, because of postoperative renal dysfunction in thousands of these patients, aprotinin was voluntarily withdrawn from the market. Our earlier studies indicated that a R24K mutant of the first Kunitz-type domain of human tissue factor pathway inhibitor-2 (R24K KD1) exhibited plasmin inhibitory activity equivalent to aprotinin in vitro. In this study, we compared the effects on renal function after infusion of aprotinin and recombinant R24K KD1 in chronically instrumented, conscious rats. Aprotinin-infused rats exhibited statistically significant decreases in glomerular filtration rate and effective renal plasma flow relative to rats infused with phosphate-buffered saline (PBS) or R24K KD1 dissolved in PBS. In addition, aprotinin-treated rats exhibited marked increases in serum creatinine, blood urea nitrogen, urinary protein, and effective renal vascular resistance, whereas these renal parameters remained essentially unchanged in vehicle and R24K KD1-treated rats for a one-week period. Moreover, with use of a highly sensitive apoptosis detection assay, a significant increase in the rate of early and late apoptotic events in renal tubule cells occurred in aprotinin-treated rats relative to R24K KD1-treated rats. In addition, histological examination of the rat kidney revealed markedly higher levels of protein reabsorption droplets in the aprotinin-infused rats. Our data collectively provide suggestive evidence that R24K KD1 does not induce the renal dysfunction associated with aprotinin, and may be an effective clinical alternative to aprotinin as an antifibrinolytic agent in cardiac surgery.
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Affiliation(s)
- Prakasha Kempaiah
- Department of Pathology, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
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Kempaiah P, Chand HS, Kisiel W. Human tissue factor pathway inhibitor-2 is internalized by cells and translocated to the nucleus by the importin system. Arch Biochem Biophys 2008; 482:58-65. [PMID: 19103149 DOI: 10.1016/j.abb.2008.11.028] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2008] [Revised: 11/24/2008] [Accepted: 11/29/2008] [Indexed: 12/27/2022]
Abstract
Tissue factor pathway inhibitor-2 (TFPI-2) is a serine proteinase inhibitor that induces caspase-mediated apoptosis when offered to a variety of tumor cells. In order to investigate the mechanism of TFPI-2-induced apoptosis, we initially studied the uptake and trafficking of TFPI-2 by HT-1080 cells. Exogenously offered TFPI-2 was rapidly internalized and distributed in both the cytosolic and nuclear fractions. Nuclear localization of TFPI-2 was also detected in a variety of endothelial cells constitutively expressing TFPI-2. Nuclear localization of TFPI-2 required a NLS sequence located in its Lys/Arg-rich C-terminal tail comprising residues 191-211, as a TFPI-2 construct lacking the C-terminal tail failed to localize to the nucleus. Complexes of TFPI-2 and importin-alpha were co-immunoprecipitated from cell lysates of HT-1080 cells either offered or overexpressing this protein, providing evidence that TFPI-2 was shuttled to the nucleus by the importin system. Our results provide the initial description of TFPI-2 internalization and translocation to the nucleus in a number of cells.
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Affiliation(s)
- Prakasha Kempaiah
- Department of Pathology, University of New Mexico Health Sciences Center, Albuquerque, NM 87131-0001, USA
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Jiang C, Bao R, Chen Y. Expression, purification, crystallization and preliminary X-ray diffraction analysis of Sagittaria sagittifolia arrowhead protease inhibitor API-A in complex with bovine trypsin. Acta Crystallogr Sect F Struct Biol Cryst Commun 2008; 64:1060-2. [PMID: 18997342 DOI: 10.1107/s1744309108032454] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2008] [Accepted: 10/08/2008] [Indexed: 11/10/2022]
Abstract
Protease inhibitors play key roles in physiological processes. Arrowhead protease inhibitor A (API-A), a member of the serine protease inhibitor family, can inhibit two trypsin molecules simultaneously. In the present work, API-A from Sagittaria sagittifolia has been cloned, expressed, purified and crystallized in complex with bovine trypsin. The crystals were obtained by the sitting-drop method. A data set was collected to 2.48 A resolution from a single crystal. The crystal belonged to space group C222(1), with unit-cell parameters a = 76.63, b = 110.86, c = 152.99 A, alpha = beta = gamma = 90 degrees .
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Affiliation(s)
- Chunhui Jiang
- Institute of Protein Research, Tongji University, Shanghai 200092, People's Republic of China
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Macedo-Ribeiro S, Almeida C, Calisto BM, Friedrich T, Mentele R, Stürzebecher J, Fuentes-Prior P, Pereira PJB. Isolation, cloning and structural characterisation of boophilin, a multifunctional Kunitz-type proteinase inhibitor from the cattle tick. PLoS One 2008; 3:e1624. [PMID: 18286181 PMCID: PMC2230226 DOI: 10.1371/journal.pone.0001624] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2007] [Accepted: 01/20/2008] [Indexed: 11/19/2022] Open
Abstract
Inhibitors of coagulation factors from blood-feeding animals display a wide variety of structural motifs and inhibition mechanisms. We have isolated a novel inhibitor from the cattle tick Boophilus microplus, one of the most widespread parasites of farm animals. The inhibitor, which we have termed boophilin, has been cloned and overexpressed in Escherichia coli. Mature boophilin is composed of two canonical Kunitz-type domains, and inhibits not only the major procoagulant enzyme, thrombin, but in addition, and by contrast to all other previously characterised natural thrombin inhibitors, significantly interferes with the proteolytic activity of other serine proteinases such as trypsin and plasmin. The crystal structure of the bovine α-thrombin·boophilin complex, refined at 2.35 Å resolution reveals a non-canonical binding mode to the proteinase. The N-terminal region of the mature inhibitor, Q16-R17-N18, binds in a parallel manner across the active site of the proteinase, with the guanidinium group of R17 anchored in the S1 pocket, while the C-terminal Kunitz domain is negatively charged and docks into the basic exosite I of thrombin. This binding mode resembles the previously characterised thrombin inhibitor, ornithodorin which, unlike boophilin, is composed of two distorted Kunitz modules. Unexpectedly, both boophilin domains adopt markedly different orientations when compared to those of ornithodorin, in its complex with thrombin. The N-terminal boophilin domain rotates 9° and is displaced by 6 Å, while the C-terminal domain rotates almost 6° accompanied by a 3 Å displacement. The reactive-site loop of the N-terminal Kunitz domain of boophilin with its P1 residue, K31, is fully solvent exposed and could thus bind a second trypsin-like proteinase without sterical restraints. This finding explains the formation of a ternary thrombin·boophilin·trypsin complex, and suggests a mechanism for prothrombinase inhibition in vivo.
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Affiliation(s)
- Sandra Macedo-Ribeiro
- Centro de Neurociências e Biologia Celular (CNC), Coimbra, Portugal
- Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto, Porto, Portugal
| | - Carla Almeida
- Centro de Neurociências e Biologia Celular (CNC), Coimbra, Portugal
| | - Bárbara M. Calisto
- Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto, Porto, Portugal
| | | | | | | | - Pablo Fuentes-Prior
- Cardiovascular Research Center, Consejo Superior de Investigaciones Científicas (CSIC)-Institut Català de Ciències Cardiovasculars (ICCC), Barcelona, Spain
- *E-mail: (PF); (PP)
| | - Pedro José Barbosa Pereira
- Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto, Porto, Portugal
- *E-mail: (PF); (PP)
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Zhang C, Kong D, Liu X, Yan X, Dai L, Ma D. Spectroscopic analysis on the effect of temperature on Kunitz domain 1 of human tissue factor pathway inhibitor-2. Acta Biochim Biophys Sin (Shanghai) 2007; 39:406-12. [PMID: 17558445 DOI: 10.1111/j.1745-7270.2007.00299.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The conformation of Kunitz domain 1 of human tissue factor pathway inhibitor-2 (hTFPI-2/KD1) has been studied by fourier transform infrared spectroscopy, circular dichroism, and Raman spectroscopy. It was found that hTFPI-2/KD1 contained approximately 17% alpha-helices, 24% beta-strands, 46% random coils, 13% beta-turns, and two kinds of disulfide bonds(ggg and tgt) at 25 degrees C. The detailed conformational changes of the heated protein observed by fourier transform infrared spectroscopy, circular dichroism and Raman spectroscopy revealed that hTFPI-2/KD1 was thermally stable. However, KD1 could form an intermediate form at high temperature, then return to its normal conformation when the temperature was lowered. Activity assays also showed that hTFPI-2/KD1 was able to keep its inhibitory activity on plasmin after being heated to 80 degrees C for 5 min.
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Affiliation(s)
- Chenqi Zhang
- Center of Analysis and Measurement, Fudan University, Shanghai 200433, China
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Xu Z, Maiti D, Kisiel W, Duh EJ. Tissue Factor Pathway Inhibitor-2 Is Upregulated by Vascular Endothelial Growth Factor and Suppresses Growth Factor-Induced Proliferation of Endothelial Cells. Arterioscler Thromb Vasc Biol 2006; 26:2819-25. [PMID: 17023682 DOI: 10.1161/01.atv.0000248731.55781.87] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective—
The purpose of this study is to investigate the expression and regulation of type-2 tissue factor pathway inhibitor (TFPI-2) in endothelial cells, as well as the regulation of human endothelial cell (EC) function by TFPI-2.
Methods and Results—
Real-time polymerase chain reaction (PCR) and Western blot analysis revealed that vascular endothelial growth factor (VEGF) induced both time- and dose-dependent increase in TFPI-2 mRNA and protein expression in endothelial cells. TFPI-2 mRNA expression was also significantly upregulated by IL-1β, and modestly increased by both tumor necrosis factor (TNF)-α and fibroblast growth factor (FGF)-2, but not placental growth factor (PlGF). VEGF upregulation of TFPI-2 was dramatically reduced by inhibition of the MEK pathway. Administration of TFPI-2 protein suppressed both VEGF and FGF-2 stimulation of EC proliferation in a dose-dependent manner. A recombinant preparation of the first Kunitz-type domain of TFPI-2 (KD1) did not suppress growth factor stimulation of EC proliferation, suggesting a mechanism distinct from the proteinase inhibitory activity of TFPI-2. Exogenously added TFPI-2 protein suppressed VEGF-induced EC migration in 2 different assays. Recombinant wt-KD1 or the R24K mutant of KD1, but not the R24Q mutant, dramatically suppressed VEGF-induced EC migration. TFPI-2 protein, but not recombinant KD1, blocked VEGF-induced activation of both Akt and ERK1/2 in ECs. At higher doses, TFPI-2 protein blocked VEGFR2 activation.
Conclusion—
Our data suggest that VEGF-upregulation of TFPI-2 expression in endothelial cells may represent a mechanism for negative feedback regulation and modulation of its pro-angiogenic action on endothelial cells. TFPI-2, or derivatives of TFPI-2, may be novel therapeutics for treatment of angiogenic disease processes.
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Affiliation(s)
- Zhenhua Xu
- Department of Ophthalmology, The Wilmer Ophthalmological Institute, The Johns Hopkins University School of Medicine, 1550 Orleans Street, Baltimore, MD 21231, USA
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Carlsson K, Persson E, Carlsson U, Svensson M. Inhibitors of factor VIIa affect the interface between the protease domain and tissue factor. Biochem Biophys Res Commun 2006; 349:1111-6. [PMID: 16970919 DOI: 10.1016/j.bbrc.2006.08.148] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2006] [Accepted: 08/25/2006] [Indexed: 11/25/2022]
Abstract
Blood coagulation is triggered by the formation of a complex between factor VIIa (FVIIa) and its cofactor, tissue factor (TF). The gamma-carboxyglutamic acid-rich domain of FVIIa docks with the C-terminal domain of TF, the EGF1 domain of FVIIa contacts both domains of TF, and the EGF2 domain and protease domain (PD) form a continuous surface that sits on the N-terminal domain of TF. Our aim was to investigate the conformational changes that occur in the sTF.PD binding region when different types of inhibitors, i.e., one active-site inhibitor (FFR-chloromethyl ketone (FFR)), two different peptide exosite inhibitors (E-76 and A-183), and the natural inhibitor tissue factor pathway inhibitor (TFPI), were allowed to bind to FVIIa. For this purpose, we constructed two sTF mutants (Q37C and E91C). By the aid of site-directed labeling technique, a fluorescent label was attached to the free cysteine. The sTF.PD interface was affected in position 37 by the binding of FFR, TFPI, and E-76, i.e., a more compact structure was sensed by the probe, while for position 91 located in the same region no change in the surrounding structure was observed. Thus, the active site inhibitors FFR and TFPI, and the exosite inhibitor E-76 have similar effects on the probe in position 37 of sTF, despite their differences in size and inhibition mechanism. The allosteric changes at the active site caused by binding of the exosite inhibitor E-76 in turn induce similar conformational changes in the sTF.PD interface as does the binding of the active site inhibitors. A-183, on the other hand, did not affect position 37 in sTF, indicating that the A-183 inhibition mechanism is different from that of E-76.
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Affiliation(s)
- Karin Carlsson
- IFM-Department of Chemistry, Linköping University, SE-581 83 Linköping, Sweden
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