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Dickeson SK, Kumar S, Sun MF, Litvak M, He TZ, Phillips DR, Roberts ET, Feener EP, Law RHP, Gailani D. A mechanism for hereditary angioedema caused by a methionine-379-to-lysine substitution in kininogens. Blood 2024; 143:641-650. [PMID: 37992228 PMCID: PMC10873535 DOI: 10.1182/blood.2023022254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 10/20/2023] [Accepted: 11/13/2023] [Indexed: 11/24/2023] Open
Abstract
ABSTRACT Hereditary angioedema (HAE) is associated with episodic kinin-induced swelling of the skin and mucosal membranes. Most patients with HAE have low plasma C1-inhibitor activity, leading to increased generation of the protease plasma kallikrein (PKa) and excessive release of the nanopeptide bradykinin from high-molecular-weight kininogen (HK). However, disease-causing mutations in at least 10% of patients with HAE appear to involve genes for proteins other than C1-inhibitor. A point mutation in the Kng1 gene encoding HK and low-molecular weight kininogen (LK) was identified recently in a family with HAE. The mutation changes a methionine (Met379) to lysine (Lys379) in both proteins. Met379 is adjacent to the Lys380-Arg381 cleavage site at the N-terminus of the bradykinin peptide. Recombinant wild-type (Met379) and variant (Lys379) versions of HK and LK were expressed in HEK293 cells. PKa-catalyzed kinin release from HK and LK was not affected by the Lys379 substitutions. However, kinin release from HK-Lys379 and LK-Lys379 catalyzed by the fibrinolytic protease plasmin was substantially greater than from wild-type HK-Met379 and LK-Met379. Increased kinin release was evident when fibrinolysis was induced in plasma containing HK-Lys379 or LK-Lys379 compared with plasma containing wild-type HK or LK. Mass spectrometry revealed that the kinin released from wild-type and variant kininogens by PKa is bradykinin. Plasmin also released bradykinin from wild-type kininogens but cleaved HK-Lys379 and LK-Lys379 after Lys379 rather than Lys380, releasing the decapeptide Lys-bradykinin (kallidin). The Met379Lys substitutions make HK and LK better plasmin substrates, reinforcing the relationship between fibrinolysis and kinin generation.
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Affiliation(s)
- S. Kent Dickeson
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN
| | - Sunil Kumar
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN
| | - Mao-fu Sun
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN
| | - Maxim Litvak
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN
| | - Tracey Z. He
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN
| | | | | | | | - Ruby H. P. Law
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia
| | - David Gailani
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN
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Cramer DAT, Yin V, Caval T, Franc V, Yu D, Wu G, Lloyd G, Langendorf C, Whisstock JC, Law RHP, Heck AJR. Proteoform-Resolved Profiling of Plasminogen Activation Reveals Novel Abundant Phosphorylation Site and Primary N-Terminal Cleavage Site. Mol Cell Proteomics 2024; 23:100696. [PMID: 38101751 PMCID: PMC10825491 DOI: 10.1016/j.mcpro.2023.100696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 12/07/2023] [Accepted: 12/11/2023] [Indexed: 12/17/2023] Open
Abstract
Plasminogen (Plg), the zymogen of plasmin (Plm), is a glycoprotein involved in fibrinolysis and a wide variety of other physiological processes. Plg dysregulation has been implicated in a range of diseases. Classically, human Plg is categorized into two types, supposedly having different functional features, based on the presence (type I) or absence (type II) of a single N-linked glycan. Using high-resolution native mass spectrometry, we uncovered that the proteoform profiles of human Plg (and Plm) are substantially more extensive than this simple binary classification. In samples derived from human plasma, we identified up to 14 distinct proteoforms of Plg, including a novel highly stoichiometric phosphorylation site at Ser339. To elucidate the potential functional effects of these post-translational modifications, we performed proteoform-resolved kinetic analyses of the Plg-to-Plm conversion using several canonical activators. This conversion is thought to involve at least two independent cleavage events: one to remove the N-terminal peptide and another to release the active catalytic site. Our analyses reveal that these processes are not independent but are instead tightly regulated and occur in a step-wise manner. Notably, N-terminal cleavage at the canonical site (Lys77) does not occur directly from intact Plg. Instead, an activation intermediate corresponding to cleavage at Arg68 is initially produced, which only then is further processed to the canonical Lys77 product. Based on our results, we propose a refined categorization for human Plg proteoforms. In addition, we reveal that the proteoform profile of human Plg is more extensive than that of rat Plg, which lacks, for instance, the here-described phosphorylation at Ser339.
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Affiliation(s)
- Dario A T Cramer
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Science, University of Utrecht, Utrecht, The Netherlands; Netherlands Proteomics Centre, University of Utrecht, Utrecht, The Netherlands
| | - Victor Yin
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Science, University of Utrecht, Utrecht, The Netherlands; Netherlands Proteomics Centre, University of Utrecht, Utrecht, The Netherlands
| | - Tomislav Caval
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Science, University of Utrecht, Utrecht, The Netherlands; Netherlands Proteomics Centre, University of Utrecht, Utrecht, The Netherlands
| | - Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Science, University of Utrecht, Utrecht, The Netherlands; Netherlands Proteomics Centre, University of Utrecht, Utrecht, The Netherlands
| | - Dingyi Yu
- Mass Spectrometry Facility, St Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia
| | - Guojie Wu
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria, Australia
| | - Gordon Lloyd
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria, Australia
| | - Christopher Langendorf
- Mass Spectrometry Facility, St Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia
| | - James C Whisstock
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria, Australia
| | - Ruby H P Law
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria, Australia.
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Science, University of Utrecht, Utrecht, The Netherlands; Netherlands Proteomics Centre, University of Utrecht, Utrecht, The Netherlands.
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3
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Jose J, Law RHP, Leung EWW, Wai DCC, Akhlaghi H, Chandrashekaran IR, Caradoc-Davies TT, Voskoboinik I, Feutrill J, Middlemiss D, Jeevarajah D, Bashtannyk-Puhalovich T, Giddens AC, Lee TW, Jamieson SMF, Trapani JA, Whisstock JC, Spicer JA, Norton RS. Fragment-based and structure-guided discovery of perforin inhibitors. Eur J Med Chem 2023; 261:115786. [PMID: 37716187 DOI: 10.1016/j.ejmech.2023.115786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 08/24/2023] [Accepted: 08/31/2023] [Indexed: 09/18/2023]
Abstract
Perforin is a pore-forming protein whose normal function enables cytotoxic T and natural killer (NK) cells to kill virus-infected and transformed cells. Conversely, unwanted perforin activity can also result in auto-immune attack, graft rejection and aberrant responses to pathogens. Perforin is critical for the function of the granule exocytosis cell death pathway and is therefore a target for drug development. In this study, by screening a fragment library using NMR and surface plasmon resonance, we identified 4,4-diaminodiphenyl sulfone (dapsone) as a perforin ligand. We also found that dapsone has modest (mM) inhibitory activity of perforin lytic activity in a red blood cell lysis assay in vitro. Sequential modification of this lead fragment, guided by structural knowledge of the ligand binding site and binding pose, and supported by SPR and ligand-detected 19F NMR, enabled the design of nanomolar inhibitors of the cytolytic activity of intact NK cells against various tumour cell targets. Interestingly, the ligands we developed were largely inert with respect to direct perforin-mediated red blood cell lysis but were very potent in the context of perforin's action on delivering granzymes in the immune synapse, the context in which it functions physiologically. Our work indicates that a fragment-based, structure-guided drug discovery strategy can be used to identify novel ligands that bind perforin. Moreover, these molecules have superior physicochemical properties and solubility compared to previous generations of perforin ligands.
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Affiliation(s)
- Jiney Jose
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, A New Zealand Centre for Research Excellence, Auckland, New Zealand
| | - Ruby H P Law
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, 3800, Australia
| | - Eleanor W W Leung
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
| | - Dorothy C C Wai
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
| | - Hedieh Akhlaghi
- Cancer Immunology Program, Peter MacCallum Cancer Centre, 305 Grattan Street, Melbourne, VIC, 3000, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, 3052, Australia
| | - Indu R Chandrashekaran
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia; ARC Centre for Fragment-Based Design, Monash University, Parkville, VIC, 3052, Australia
| | - Tom T Caradoc-Davies
- Australian Synchrotron, 800 Blackburn Rd., Clayton, Melbourne, VIC, 3168, Australia
| | - Ilia Voskoboinik
- Cancer Immunology Program, Peter MacCallum Cancer Centre, 305 Grattan Street, Melbourne, VIC, 3000, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, 3052, Australia
| | - John Feutrill
- SYNthesis med chem (Australia) Pty Ltd, Bio21 Institute, 30 Flemington Road, Parkville, VIC, 3052, Australia
| | - David Middlemiss
- XaviaPharm, Bishop's Stortford, CM23 5EX, England, United Kingdom
| | - Devadharshini Jeevarajah
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, 3800, Australia
| | | | - Anna C Giddens
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
| | - Tet Woo Lee
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
| | - Stephen M F Jamieson
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, A New Zealand Centre for Research Excellence, Auckland, New Zealand; Department of Pharmacology and Clinical Pharmacology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
| | - Joseph A Trapani
- Cancer Immunology Program, Peter MacCallum Cancer Centre, 305 Grattan Street, Melbourne, VIC, 3000, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, 3052, Australia
| | - James C Whisstock
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, 3800, Australia.
| | - Julie A Spicer
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, A New Zealand Centre for Research Excellence, Auckland, New Zealand.
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia; ARC Centre for Fragment-Based Design, Monash University, Parkville, VIC, 3052, Australia.
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Quek AJ, Cowieson NP, Caradoc-Davies TT, Conroy PJ, Whisstock JC, Law RHP. A High-Throughput Small-Angle X-ray Scattering Assay to Determine the Conformational Change of Plasminogen. Int J Mol Sci 2023; 24:14258. [PMID: 37762561 PMCID: PMC10531915 DOI: 10.3390/ijms241814258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Revised: 09/09/2023] [Accepted: 09/11/2023] [Indexed: 09/29/2023] Open
Abstract
Plasminogen (Plg) is the inactive form of plasmin (Plm) that exists in two major glycoforms, referred to as glycoforms I and II (GI and GII). In the circulation, Plg assumes an activation-resistant "closed" conformation via interdomain interactions and is mediated by the lysine binding site (LBS) on the kringle (KR) domains. These inter-domain interactions can be readily disrupted when Plg binds to lysine/arginine residues on protein targets or free L-lysine and analogues. This causes Plg to convert into an "open" form, which is crucial for activation by host activators. In this study, we investigated how various ligands affect the kinetics of Plg conformational change using small-angle X-ray scattering (SAXS). We began by examining the open and closed conformations of Plg using size-exclusion chromatography (SEC) coupled with SAXS. Next, we developed a high-throughput (HTP) 96-well SAXS assay to study the conformational change of Plg. This method enables us to determine the Kopen value, which is used to directly compare the effect of different ligands on Plg conformation. Based on our analysis using Plg GII, we have found that the Kopen of ε-aminocaproic acid (EACA) is approximately three times greater than that of tranexamic acid (TXA), which is widely recognized as a highly effective ligand. We demonstrated further that Plg undergoes a conformational change when it binds to the C-terminal peptides of the inhibitor α2-antiplasmin (α2AP) and receptor Plg-RKT. Our findings suggest that in addition to the C-terminal lysine, internal lysine(s) are also necessary for the formation of open Plg. Finally, we compared the conformational changes of Plg GI and GII directly and found that the closed form of GI, which has an N-linked glycosylation, is less stable. To summarize, we have successfully determined the response of Plg to various ligand/receptor peptides by directly measuring the kinetics of its conformational changes.
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Affiliation(s)
- Adam J. Quek
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, VIC 3800, Australia
| | - Nathan P. Cowieson
- Diamond Light Source Ltd., Diamond House, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK
| | - Tom T. Caradoc-Davies
- Australian Synchrotron, ANSTO_Melbourne, 800 Blackburn Rd., Clayton, VIC 3168, Australia
| | - Paul J. Conroy
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, VIC 3800, Australia
| | - James C. Whisstock
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, VIC 3800, Australia
| | - Ruby H. P. Law
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, VIC 3800, Australia
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5
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Whisstock JC, Law RHP. The role of NINJ1 protein in programmed cellular destruction. Nature 2023:10.1038/d41586-023-01602-z. [PMID: 37198463 DOI: 10.1038/d41586-023-01602-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
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Wiedemeyer SJA, Wu G, Pham TLP, Lang-Henkel H, Perez Urzua B, Whisstock JC, Law RHP, Steinmetzer T. Synthesis and Structural Characterization of Macrocyclic Plasmin Inhibitors. ChemMedChem 2023; 18:e202200632. [PMID: 36710259 DOI: 10.1002/cmdc.202200632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 01/25/2023] [Accepted: 01/27/2023] [Indexed: 01/31/2023]
Abstract
Two series of macrocyclic plasmin inhibitors with a C-terminal benzylamine group were synthesized. The substitution of the N-terminal phenylsulfonyl group of a previously described inhibitor provided two analogues with sub-nanomolar inhibition constants. Both compounds possess a high selectivity against all other tested trypsin-like serine proteases. Furthermore, a new approach was used to selectively introduce asymmetric linker segments. Two of these compounds inhibit plasmin with Ki values close to 2 nM. For the first time, four crystal structures of these macrocyclic inhibitors could be determined in complex with a Ser195Ala microplasmin mutant. The macrocyclic core segment of the inhibitors binds to the open active site of plasmin without any steric hindrance. This binding mode is incompatible with other trypsin-like serine proteases containing a sterically demanding 99-hairpin loop. The crystal structures obtained experimentally explain the excellent selectivity of this inhibitor type as previously hypothesized.
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Affiliation(s)
- Simon J A Wiedemeyer
- Department of Pharmacy Institute of Pharmaceutical Chemistry, Philipps University Marburg, Marbacher Weg 6, 35032, Marburg, Germany
| | - Guojie Wu
- Biomedicine Discovery Institute Department of Biochemistry and Molecular Biology, Monash University, Melbourne, 3800, Australia
| | - T L Phuong Pham
- Department of Pharmacy Institute of Pharmaceutical Chemistry, Philipps University Marburg, Marbacher Weg 6, 35032, Marburg, Germany
| | - Heike Lang-Henkel
- Department of Pharmacy Institute of Pharmaceutical Chemistry, Philipps University Marburg, Marbacher Weg 6, 35032, Marburg, Germany
| | - Benjamin Perez Urzua
- Department of Cellular and Molecular Biology Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, 8331150, Chile
| | - James C Whisstock
- Biomedicine Discovery Institute Department of Biochemistry and Molecular Biology, Monash University, Melbourne, 3800, Australia
| | - Ruby H P Law
- Biomedicine Discovery Institute Department of Biochemistry and Molecular Biology, Monash University, Melbourne, 3800, Australia
| | - Torsten Steinmetzer
- Department of Pharmacy Institute of Pharmaceutical Chemistry, Philipps University Marburg, Marbacher Weg 6, 35032, Marburg, Germany
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Wiedemeyer SJA, Wu G, Pham TLP, Lang‐Henkel H, Perez Urzua B, Whisstock JC, Law RHP, Steinmetzer T. Front Cover: Synthesis and Structural Characterization of Macrocyclic Plasmin Inhibitors (ChemMedChem 6/2023). ChemMedChem 2023. [DOI: 10.1002/cmdc.202300137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/15/2023]
Affiliation(s)
- Simon J. A. Wiedemeyer
- Department of Pharmacy Institute of Pharmaceutical Chemistry Philipps University Marburg Marbacher Weg 6 35032 Marburg Germany
| | - Guojie Wu
- Biomedicine Discovery Institute Department of Biochemistry and Molecular Biology Monash University Melbourne 3800 Australia
| | - T. L. Phuong Pham
- Department of Pharmacy Institute of Pharmaceutical Chemistry Philipps University Marburg Marbacher Weg 6 35032 Marburg Germany
| | - Heike Lang‐Henkel
- Department of Pharmacy Institute of Pharmaceutical Chemistry Philipps University Marburg Marbacher Weg 6 35032 Marburg Germany
| | - Benjamin Perez Urzua
- Department of Cellular and Molecular Biology Faculty of Biological Sciences Pontificia Universidad Católica de Chile Santiago 8331150 Chile
| | - James C Whisstock
- Biomedicine Discovery Institute Department of Biochemistry and Molecular Biology Monash University Melbourne 3800 Australia
| | - Ruby H. P. Law
- Biomedicine Discovery Institute Department of Biochemistry and Molecular Biology Monash University Melbourne 3800 Australia
| | - Torsten Steinmetzer
- Department of Pharmacy Institute of Pharmaceutical Chemistry Philipps University Marburg Marbacher Weg 6 35032 Marburg Germany
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Dickeson SK, Kumar S, Sun MF, Mohammed BM, Phillips DR, Whisstock JC, Quek AJ, Feener EP, Law RHP, Gailani D. A mechanism for hereditary angioedema caused by a lysine 311-to-glutamic acid substitution in plasminogen. Blood 2022; 139:2816-2829. [PMID: 35100351 PMCID: PMC9074402 DOI: 10.1182/blood.2021012945] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 01/18/2022] [Indexed: 11/20/2022] Open
Abstract
Patients with hereditary angioedema (HAE) experience episodes of bradykinin (BK)-induced swelling of skin and mucosal membranes. The most common cause is reduced plasma activity of C1 inhibitor, the main regulator of the proteases plasma kallikrein (PKa) and factor XIIa (FXIIa). Recently, patients with HAE were described with a Lys311 to glutamic acid substitution in plasminogen (Plg), the zymogen of the protease plasmin (Plm). Adding tissue plasminogen activator to plasma containing Plg-Glu311 vs plasma containing wild-type Plg (Plg-Lys311) results in greater BK generation. Similar results were obtained in plasma lacking prekallikrein or FXII (the zymogens of PKa and FXIIa) and in normal plasma treated with a PKa inhibitor, indicating Plg-Glu311 induces BK generation independently of PKa and FXIIa. Plm-Glu311 cleaves high and low molecular weight kininogens (HK and LK, respectively), releasing BK more efficiently than Plm-Lys311. Based on the plasma concentrations of HK and LK, the latter may be the source of most of the BK generated by Plm-Glu311. The lysine analog ε-aminocaproic acid blocks Plm-catalyzed BK generation. The Glu311 substitution introduces a lysine-binding site into the Plg kringle 3 domain, perhaps altering binding to kininogens. Plg residue 311 is glutamic acid in most mammals. Glu311 in patients with HAE, therefore, represents reversion to the ancestral condition. Substantial BK generation occurs during Plm-Glu311 cleavage of human HK, but not mouse HK. Furthermore, mouse Plm, which has Glu311, did not liberate BK from human kininogens more rapidly than human Plg-Lys311. This indicates Glu311 is pathogenic in the context of human Plm when human kininogens are the substrates.
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Affiliation(s)
- S Kent Dickeson
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN
| | - Sunil Kumar
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN
| | - Mao-Fu Sun
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN
| | - Bassem M Mohammed
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN
| | | | - James C Whisstock
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia; and
| | - Adam J Quek
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia; and
| | | | - Ruby H P Law
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia; and
| | - David Gailani
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, Nashville, TN
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Awad MM, Hutton ML, Quek AJ, Klare WP, Mileto SJ, Mackin K, Ly D, Oorschot V, Bosnjak M, Jenkin G, Conroy PJ, West N, Fulcher A, Costin A, Day CJ, Jennings MP, Medcalf RL, Sanderson-Smith M, Cordwell SJ, Law RHP, Whisstock JC, Lyras D. Human Plasminogen Exacerbates Clostridioides difficile Enteric Disease and Alters the Spore Surface. Gastroenterology 2020; 159:1431-1443.e6. [PMID: 32574621 DOI: 10.1053/j.gastro.2020.06.032] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 06/10/2020] [Accepted: 06/13/2020] [Indexed: 12/15/2022]
Abstract
BACKGROUND & AIMS The protease plasmin is an important wound healing factor, but it is not clear how it affects gastrointestinal infection-mediated damage, such as that resulting from Clostridioides difficile. We investigated the role of plasmin in C difficile-associated disease. This bacterium produces a spore form that is required for infection, so we also investigated the effects of plasmin on spores. METHODS C57BL/6J mice expressing the precursor to plasmin, the zymogen human plasminogen (hPLG), or infused with hPLG were infected with C difficile, and disease progression was monitored. Gut tissues were collected, and cytokine production and tissue damage were analyzed by using proteomic and cytokine arrays. Antibodies that inhibit either hPLG activation or plasmin activity were developed and structurally characterized, and their effects were tested in mice. Spores were isolated from infected patients or mice and visualized using super-resolution microscopy; the functional consequences of hPLG binding to spores were determined. RESULTS hPLG localized to the toxin-damaged gut, resulting in immune dysregulation with an increased abundance of cytokines (such as interleukin [IL] 1A, IL1B, IL3, IL10, IL12B, MCP1, MP1A, MP1B, GCSF, GMCSF, KC, TIMP-1), tissue degradation, and reduced survival. Administration of antibodies that inhibit plasminogen activation reduced disease severity in mice. C difficile spores bound specifically to hPLG and active plasmin degraded their surface, facilitating rapid germination. CONCLUSIONS We found that hPLG is recruited to the damaged gut, exacerbating C difficile disease in mice. hPLG binds to C difficile spores, and, upon activation to plasmin, remodels the spore surface, facilitating rapid spore germination. Inhibitors of plasminogen activation might be developed for treatment of C difficile or other infection-mediated gastrointestinal diseases.
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Affiliation(s)
- Milena M Awad
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Australia
| | - Melanie L Hutton
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Australia
| | - Adam J Quek
- Australian Research Council Centre of Excellence in Advanced Molecular Imaging and Biomedicine Discovery Institute, Department of Biochemistry, Monash University, Clayton, Australia
| | - William P Klare
- School of Life and Environmental Sciences and Charles Perkins Centre, The University of Sydney, Sydney, Australia
| | - Steven J Mileto
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Australia
| | - Kate Mackin
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Australia
| | - Diane Ly
- Illawarra health and Medical Research Institute, Wollongong, Australia; School of Chemistry and Molecular Bioscience and Molecular Horizons, University of Wollongong, Wollongong, Australia
| | - Viola Oorschot
- Australian Research Council Centre of Excellence in Advanced Molecular Imaging and Biomedicine Discovery Institute, Department of Biochemistry, Monash University, Clayton, Australia; Monash Micro Imaging, Monash University, Clayton, Australia
| | - Marijana Bosnjak
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Australia
| | - Grant Jenkin
- Monash Infectious Diseases, Monash Health, Clayton, Australia
| | - Paul J Conroy
- Australian Research Council Centre of Excellence in Advanced Molecular Imaging and Biomedicine Discovery Institute, Department of Biochemistry, Monash University, Clayton, Australia
| | - Nick West
- School of Chemistry and Molecular Biosciences and Australian Infectious Diseases Research Centre, University of Queensland, St. Lucia, Australia
| | - Alex Fulcher
- Monash Micro Imaging, Monash University, Clayton, Australia
| | - Adam Costin
- Australian Research Council Centre of Excellence in Advanced Molecular Imaging and Biomedicine Discovery Institute, Department of Biochemistry, Monash University, Clayton, Australia
| | | | | | - Robert L Medcalf
- Molecular Neurotrauma and Haemostasis, Australian Centre for Blood Diseases, Monash University, Clayton, Australia
| | - Martina Sanderson-Smith
- Illawarra health and Medical Research Institute, Wollongong, Australia; School of Chemistry and Molecular Bioscience and Molecular Horizons, University of Wollongong, Wollongong, Australia
| | - Stuart J Cordwell
- School of Life and Environmental Sciences and Charles Perkins Centre, The University of Sydney, Sydney, Australia
| | - Ruby H P Law
- Australian Research Council Centre of Excellence in Advanced Molecular Imaging and Biomedicine Discovery Institute, Department of Biochemistry, Monash University, Clayton, Australia
| | - James C Whisstock
- Australian Research Council Centre of Excellence in Advanced Molecular Imaging and Biomedicine Discovery Institute, Department of Biochemistry, Monash University, Clayton, Australia; European Molecular Biology Laboratory Australia, Monash University, Clayton, Australia; South East University-Monash Joint Institute, Institute of Life Sciences, Southeast University, Nanjing, China
| | - Dena Lyras
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Australia.
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10
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White AM, Veer SJ, Wu G, Harvey PJ, Yap K, King GJ, Swedberg JE, Wang CK, Law RHP, Durek T, Craik DJ. Inside Cover: Application and Structural Analysis of Triazole‐Bridged Disulfide Mimetics in Cyclic Peptides (Angew. Chem. Int. Ed. 28/2020). Angew Chem Int Ed Engl 2020. [DOI: 10.1002/anie.202006713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Andrew M. White
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Simon J. Veer
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Guojie Wu
- ARC Centre of Excellence in Advanced Molecular Imaging Department of Biochemistry and Molecular Biology Biomedicine Discovery Institute Monash University Clayton VIC 3800 Australia
| | - Peta J. Harvey
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Kuok Yap
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Gordon J. King
- The Centre for Microscopy and Microanalysis The University of Queensland Brisbane QLD 4072 Australia
| | - Joakim E. Swedberg
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Conan K. Wang
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Ruby H. P. Law
- ARC Centre of Excellence in Advanced Molecular Imaging Department of Biochemistry and Molecular Biology Biomedicine Discovery Institute Monash University Clayton VIC 3800 Australia
| | - Thomas Durek
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - David J. Craik
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
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11
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White AM, Veer SJ, Wu G, Harvey PJ, Yap K, King GJ, Swedberg JE, Wang CK, Law RHP, Durek T, Craik DJ. Innentitelbild: Application and Structural Analysis of Triazole‐Bridged Disulfide Mimetics in Cyclic Peptides (Angew. Chem. 28/2020). Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202006713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Andrew M. White
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Simon J. Veer
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Guojie Wu
- ARC Centre of Excellence in Advanced Molecular Imaging Department of Biochemistry and Molecular Biology Biomedicine Discovery Institute Monash University Clayton VIC 3800 Australia
| | - Peta J. Harvey
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Kuok Yap
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Gordon J. King
- The Centre for Microscopy and Microanalysis The University of Queensland Brisbane QLD 4072 Australia
| | - Joakim E. Swedberg
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Conan K. Wang
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Ruby H. P. Law
- ARC Centre of Excellence in Advanced Molecular Imaging Department of Biochemistry and Molecular Biology Biomedicine Discovery Institute Monash University Clayton VIC 3800 Australia
| | - Thomas Durek
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - David J. Craik
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
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12
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White AM, Veer SJ, Wu G, Harvey PJ, Yap K, King GJ, Swedberg JE, Wang CK, Law RHP, Durek T, Craik DJ. Application and Structural Analysis of Triazole‐Bridged Disulfide Mimetics in Cyclic Peptides. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202003435] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Andrew M. White
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Simon J. Veer
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Guojie Wu
- ARC Centre of Excellence in Advanced Molecular Imaging Department of Biochemistry and Molecular Biology Biomedicine Discovery Institute Monash University Clayton VIC 3800 Australia
| | - Peta J. Harvey
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Kuok Yap
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Gordon J. King
- The Centre for Microscopy and Microanalysis The University of Queensland Brisbane QLD 4072 Australia
| | - Joakim E. Swedberg
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Conan K. Wang
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Ruby H. P. Law
- ARC Centre of Excellence in Advanced Molecular Imaging Department of Biochemistry and Molecular Biology Biomedicine Discovery Institute Monash University Clayton VIC 3800 Australia
| | - Thomas Durek
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - David J. Craik
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
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13
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White AM, Veer SJ, Wu G, Harvey PJ, Yap K, King GJ, Swedberg JE, Wang CK, Law RHP, Durek T, Craik DJ. Application and Structural Analysis of Triazole‐Bridged Disulfide Mimetics in Cyclic Peptides. Angew Chem Int Ed Engl 2020; 59:11273-11277. [DOI: 10.1002/anie.202003435] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Indexed: 12/20/2022]
Affiliation(s)
- Andrew M. White
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Simon J. Veer
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Guojie Wu
- ARC Centre of Excellence in Advanced Molecular Imaging Department of Biochemistry and Molecular Biology Biomedicine Discovery Institute Monash University Clayton VIC 3800 Australia
| | - Peta J. Harvey
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Kuok Yap
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Gordon J. King
- The Centre for Microscopy and Microanalysis The University of Queensland Brisbane QLD 4072 Australia
| | - Joakim E. Swedberg
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Conan K. Wang
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - Ruby H. P. Law
- ARC Centre of Excellence in Advanced Molecular Imaging Department of Biochemistry and Molecular Biology Biomedicine Discovery Institute Monash University Clayton VIC 3800 Australia
| | - Thomas Durek
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
| | - David J. Craik
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Institute for Molecular Bioscience The University of Queensland Brisbane QLD 4072 Australia
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14
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Kryza T, Khan T, Puttick S, Li C, Sokolowski KA, Tse BWC, Cuda T, Lyons N, Gough M, Yin J, Parkin A, Deryugina EI, Quigley JP, Law RHP, Whisstock JC, Riddell AD, Barbour AP, Wyld DK, Thomas PA, Rose S, Snell CE, Pajic M, He Y, Hooper JD. Effective targeting of intact and proteolysed CDCP1 for imaging and treatment of pancreatic ductal adenocarcinoma. Theranostics 2020; 10:4116-4133. [PMID: 32226543 PMCID: PMC7086361 DOI: 10.7150/thno.43589] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 02/07/2020] [Indexed: 12/12/2022] Open
Abstract
Background: CUB domain-containing protein 1 (CDCP1) is a cell surface receptor regulating key signalling pathways in malignant cells. CDCP1 has been proposed as a molecular target to abrogate oncogenic signalling pathways and specifically deliver anti-cancer agents to tumors. However, the development of CDCP1-targeting agents has been questioned by its frequent proteolytic processing which was thought to result in shedding of the CDCP1 extracellular domain limiting its targetability. In this study, we investigated the relevance of targeting CDCP1 in the context of pancreatic ductal adenocarcinoma (PDAC) and assess the impact of CDCP1 proteolysis on the effectiveness of CDCP1 targeting agents. Methods: The involvement of CDCP1 in PDAC progression was assessed by association analysis in several PDAC cohorts and the proteolytic processing of CDCP1 was evaluated in PDAC cell lines and patient-derived cells. The consequences of CDCP1 proteolysis on its targetability in PDAC cells was assessed using immunoprecipitation, immunostaining and biochemical assays. The involvement of CDCP1 in PDAC progression was examined by loss-of-function in vitro and in vivo experiments employing PDAC cells expressing intact or cleaved CDCP1. Finally, we generated antibody-based imaging and therapeutic agents targeting CDCP1 to demonstrate the feasibility of targeting this receptor for detection and treatment of PDAC tumors. Results: High CDCP1 expression in PDAC is significantly associated with poorer patient survival. In PDAC cells proteolysis of CDCP1 does not always result in the shedding of CDCP1-extracellular domain which can interact with membrane-bound CDCP1 allowing signal transduction between the different CDCP1-fragments. Targeting CDCP1 impairs PDAC cell functions and PDAC tumor growth independently of CDCP1 cleavage status. A CDCP1-targeting antibody is highly effective at delivering imaging radionuclides and cytotoxins to PDAC cells allowing specific detection of tumors by PET/CT imaging and superior anti-tumor effects compared to gemcitabine in in vivo models. Conclusion: Independent of its cleavage status, CDCP1 exerts oncogenic functions in PDAC and has significant potential to be targeted for improved radiological staging and treatment of this cancer. Its elevated expression by most PDAC tumors and lack of expression by normal pancreas and other major organs, suggest that targeting CDCP1 could benefit a significant proportion of PDAC patients. These data support the further development of CDCP1-targeting agents as personalizable tools for effective imaging and treatment of PDAC.
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15
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Harrington BS, He Y, Khan T, Puttick S, Conroy PJ, Kryza T, Cuda T, Sokolowski KA, Tse BWC, Robbins KK, Arachchige BJ, Stehbens SJ, Pollock PM, Reed S, Weroha SJ, Haluska P, Salomon C, Lourie R, Perrin LC, Law RHP, Whisstock JC, Hooper JD. Anti-CDCP1 immuno-conjugates for detection and inhibition of ovarian cancer. Am J Cancer Res 2020; 10:2095-2114. [PMID: 32104500 PMCID: PMC7019151 DOI: 10.7150/thno.30736] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 12/13/2019] [Indexed: 12/12/2022] Open
Abstract
CUB-domain containing protein 1 (CDCP1) is a cancer associated cell surface protein that amplifies pro-tumorigenic signalling by other receptors including EGFR and HER2. Its potential as a cancer target is supported by studies showing that anti-CDCP1 antibodies inhibit cell migration and survival in vitro, and tumor growth and metastasis in vivo. Here we characterize two anti-CDCP1 antibodies, focusing on immuno-conjugates of one of these as a tool to detect and inhibit ovarian cancer. Methods: A panel of ovarian cancer cell lines was examined for cell surface expression of CDCP1 and loss of expression induced by anti-CDCP1 antibodies 10D7 and 41-2 using flow cytometry and Western blot analysis. Surface plasmon resonance analysis and examination of truncation mutants was used to analyse the binding properties of the antibodies for CDCP1. Live-cell spinning-disk confocal microscopy of GFP-tagged CDCP1 was used to track internalization and intracellular trafficking of CDCP1/antibody complexes. In vivo, zirconium 89-labelled 10D7 was detected by positron-emission tomography imaging, of an ovarian cancer patient-derived xenograft grown intraperitoneally in mice. The efficacy of cytotoxin-conjugated 10D7 was examined against ovarian cancer cells in vitro and in vivo. Results: Our data indicate that each antibody binds with high affinity to the extracellular domain of CDCP1 causing rapid internalization of the receptor/antibody complex and degradation of CDCP1 via processes mediated by the kinase Src. Highlighting the potential clinical utility of CDCP1, positron-emission tomography imaging, using zirconium 89-labelled 10D7, was able to detect subcutaneous and intraperitoneal xenograft ovarian cancers in mice, including small (diameter <3 mm) tumor deposits of an ovarian cancer patient-derived xenograft grown intraperitoneally in mice. Furthermore, cytotoxin-conjugated 10D7 was effective at inhibiting growth of CDCP1-expressing ovarian cancer cells in vitro and in vivo. Conclusions: These data demonstrate that CDCP1 internalizing antibodies have potential for killing and detection of CDCP1 expressing ovarian cancer cells.
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16
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Yuan Y, Ayinuola YA, Singh D, Ayinuola O, Mayfield JA, Quek A, Whisstock JC, Law RHP, Lee SW, Ploplis VA, Castellino FJ. Solution structural model of the complex of the binding regions of human plasminogen with its M-protein receptor from Streptococcus pyogenes. J Struct Biol 2019; 208:18-29. [PMID: 31301349 PMCID: PMC6983471 DOI: 10.1016/j.jsb.2019.07.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 07/01/2019] [Accepted: 07/09/2019] [Indexed: 11/22/2022]
Abstract
VEK50 is a truncated peptide from a Streptococcal pyogenes surface human plasminogen (hPg) binding M-protein (PAM). VEK50 contains the full A-domain of PAM, which is responsible for its low nanomolar binding to hPg. The interaction of VEK50 with kringle 2, the PAM-binding domain in hPg (K2hPg), has been studied by high-resolution NMR spectroscopy. The data show that each VEK50 monomer in solution contains two tight binding sites for K2hPg, one each in the a1- (RH1; R17H18) and a2- (RH2; R30H31) repeats within the A-domain of VEK50. Two mutant forms of VEK50, viz., VEK50[RH1/AA] (VEK50ΔRH1) and VEK50[RH2/AA] (VEK50ΔRH2), were designed by replacing each RH with AA, thus eliminating one of the K2hPg binding sites within VEK50, and allowing separate study of each binding site. Using 13C- and 15N-labeled peptides, NMR-derived solution structures of VEK50 in its complex with K2hPg were solved. We conclude that the A-domain of PAM can accommodate two molecules of K2hPg docked within a short distance of each other, and the strength of the binding is slightly different for each site. The solution structure of the VEK50/K2hPg, complex, which is a reductionist model of the PAM/hPg complex, provides insights for the binding mechanism of PAM to a host protein, a process that is critical to S. pyogenes virulence.
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Affiliation(s)
- Yue Yuan
- W.M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Yetunde A Ayinuola
- W.M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Damini Singh
- W.M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Olawole Ayinuola
- W.M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Jeffrey A Mayfield
- W.M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Adam Quek
- Department of Biochemistry and Molecular Biology, Monash University, Clayton 3800 VIC, Australia
| | - James C Whisstock
- Department of Biochemistry and Molecular Biology, Monash University, Clayton 3800 VIC, Australia
| | - Ruby H P Law
- Department of Biochemistry and Molecular Biology, Monash University, Clayton 3800 VIC, Australia
| | - Shaun W Lee
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Victoria A Ploplis
- W.M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, IN 46556, USA; Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Francis J Castellino
- W.M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, IN 46556, USA; Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
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17
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Quek AJH, Mazzitelli BA, Wu G, Leung EWW, Caradoc-Davies TT, Lloyd GJ, Jeevarajah D, Conroy PJ, Sanderson-Smith M, Yuan Y, Ayinuola YA, Castellino FJ, Whisstock JC, Law RHP. Structure and Function Characterization of the a1a2 Motifs of Streptococcus pyogenes M Protein in Human Plasminogen Binding. J Mol Biol 2019; 431:3804-3813. [PMID: 31295457 DOI: 10.1016/j.jmb.2019.07.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 06/28/2019] [Accepted: 07/01/2019] [Indexed: 11/30/2022]
Abstract
Plasminogen (Plg)-binding M protein (PAM) is a group A streptococcal cell surface receptor that is crucial for bacterial virulence. Previous studies revealed that, by binding to the kringle 2 (KR2) domain of host Plg, the pathogen attains a proteolytic microenvironment on the cell surface that facilitates its dissemination from the primary infection site. Each of the PAM molecules in their dimeric assembly consists of two Plg binding motifs (called the a1 and a2 repeats). To date, the molecular interactions between the a1 repeat and KR2 have been structurally characterized, whereas the role of the a2 repeat is less well defined. Here, we report the 1.7-Å x-ray crystal structure of KR2 in complex with a monomeric PAM peptide that contains both the a1 and a2 motifs. The structure reveals how the PAM peptide forms key interactions simultaneously with two KR2 via the high-affinity lysine isosteres within the a1a2 motifs. Further studies, through combined mutagenesis and functional characterization, show that a2 is a stronger KR2 binder than a1, suggesting that these two motifs may play discrete roles in mediating the final PAM-Plg assembly.
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Affiliation(s)
- Adam J H Quek
- ARC Centre of Excellence in Advanced Molecular Imaging, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Blake A Mazzitelli
- ARC Centre of Excellence in Advanced Molecular Imaging, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Guojie Wu
- ARC Centre of Excellence in Advanced Molecular Imaging, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Eleanor W W Leung
- ARC Centre of Excellence in Advanced Molecular Imaging, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Tom T Caradoc-Davies
- ARC Centre of Excellence in Advanced Molecular Imaging, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia; Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Gordon J Lloyd
- ARC Centre of Excellence in Advanced Molecular Imaging, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Devadharshini Jeevarajah
- ARC Centre of Excellence in Advanced Molecular Imaging, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Paul J Conroy
- ARC Centre of Excellence in Advanced Molecular Imaging, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Martina Sanderson-Smith
- School of Chemistry and Molecular Bioscience, University of Wollongong, and Illawarra Health and Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - Yue Yuan
- W.M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Yetunde A Ayinuola
- W.M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Francis J Castellino
- W.M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, IN 46556, USA
| | - James C Whisstock
- ARC Centre of Excellence in Advanced Molecular Imaging, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia; South East University-Monash Joint Institute, Institute of Life Sciences, Southeast University, Nanjing 210096, China.
| | - Ruby H P Law
- ARC Centre of Excellence in Advanced Molecular Imaging, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.
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18
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Swedberg JE, Wu G, Mahatmanto T, Durek T, Caradoc-Davies TT, Whisstock JC, Law RHP, Craik DJ. Highly Potent and Selective Plasmin Inhibitors Based on the Sunflower Trypsin Inhibitor-1 Scaffold Attenuate Fibrinolysis in Plasma. J Med Chem 2018; 62:552-560. [DOI: 10.1021/acs.jmedchem.8b01139] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Joakim E. Swedberg
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Guojie Wu
- ARC Centre of Excellence in Advanced Molecular Imaging, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Tunjung Mahatmanto
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Thomas Durek
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
| | | | - James C. Whisstock
- ARC Centre of Excellence in Advanced Molecular Imaging, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Ruby H. P. Law
- ARC Centre of Excellence in Advanced Molecular Imaging, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - David J. Craik
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
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19
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Li CY, de Veer SJ, Law RHP, Whisstock JC, Craik DJ, Swedberg JE. Characterising the Subsite Specificity of Urokinase-Type Plasminogen Activator and Tissue-Type Plasminogen Activator using a Sequence-Defined Peptide Aldehyde Library. Chembiochem 2018; 20:46-50. [PMID: 30225958 DOI: 10.1002/cbic.201800395] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 09/05/2018] [Indexed: 01/08/2023]
Abstract
Urokinase-type plasminogen activator (uPA) and tissue-type plasminogen activator (tPA) are two serine proteases that contribute to initiating fibrinolysis by activating plasminogen. uPA is also an important tumour-associated protease due to its role in extracellular matrix remodelling. Overexpression of uPA has been identified in several different cancers and uPA inhibition has been reported as a promising therapeutic strategy. Although several peptide-based uPA inhibitors have been developed, the extent to which uPA tolerates different tetrapeptide sequences that span the P1-P4 positions remains to be thoroughly explored. In this study, we screened a sequence-defined peptide aldehyde library against uPA and tPA. Preferred sequences from the library screen yielded potent inhibitors for uPA, led by Ac-GTAR-H (Ki =18 nm), but not for tPA. Additionally, synthetic peptide substrates corresponding to preferred inhibitor sequences were cleaved with high catalytic efficiency by uPA but not by tPA. These findings provide new insights into the binding specificity of uPA and tPA and the relative activity of tetrapeptide inhibitors and substrates against these enzymes.
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Affiliation(s)
- Choi Yi Li
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Simon J de Veer
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Ruby H P Law
- Department of Biochemistry and Molecular Biology, Biomedical Discovery Institute, Monash University, Melbourne, VIC, 3800, Australia
| | - James C Whisstock
- Department of Biochemistry and Molecular Biology, Biomedical Discovery Institute, Monash University, Melbourne, VIC, 3800, Australia
| | - David J Craik
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Joakim E Swedberg
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD, 4072, Australia
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20
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Sadek MM, Barlow N, Leung EWW, Williams-Noonan BJ, Yap BK, Shariff FM, Caradoc-Davies TT, Nicholson SE, Chalmers DK, Thompson PE, Law RHP, Norton RS. A Cyclic Peptide Inhibitor of the iNOS-SPSB Protein-Protein Interaction as a Potential Anti-Infective Agent. ACS Chem Biol 2018; 13:2930-2938. [PMID: 30226743 DOI: 10.1021/acschembio.8b00561] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
SPRY domain- and SOCS box-containing proteins SPSB1, SPSB2, and SPSB4 interact with inducible nitric oxide synthase (iNOS), causing the iNOS to be polyubiquitinated and targeted for degradation. Inhibition of this interaction increases iNOS levels, and consequently cellular nitric oxide (NO) concentrations, and has been proposed as a potential strategy for killing intracellular pathogens. We previously described two DINNN-containing cyclic peptides (CP1 and CP2) as potent inhibitors of the murine SPSB-iNOS interaction. In this study, we report the crystal structures of human SPSB4 bound to CP1 and CP2 and human SPSB2 bound to CP2. We then used these structures to design a new inhibitor in which an intramolecular hydrogen bond was replaced with a hydrocarbon linkage to form a smaller macrocycle while maintaining the bound geometry of CP2 observed in the crystal structures. This resulting pentapeptide SPSB-iNOS inhibitor (CP3) has a reduced macrocycle ring size, fewer nonbinding residues, and includes additional conformational constraints. CP3 has a greater affinity for SBSB2 ( KD = 7 nM as determined by surface plasmon resonance) and strongly inhibits the SPSB2-iNOS interaction in macrophage cell lysates. We have also determined the crystal structure of CP3 in complex with human SPSB2, which reveals the structural basis for the increased potency of CP3 and validates the original design.
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Affiliation(s)
- Maiada M. Sadek
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville Victoria 3052, Australia
| | - Nicholas Barlow
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville Victoria 3052, Australia
| | - Eleanor W. W. Leung
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville Victoria 3052, Australia
| | - Billy J. Williams-Noonan
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville Victoria 3052, Australia
| | - Beow Keat Yap
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville Victoria 3052, Australia
| | - Fairolniza Mohd Shariff
- Department of Microbiology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra, 43400 Seri Kembangan, Selangor, Malaysia
| | | | - Sandra E. Nicholson
- The Walter and Eliza Hall Institute of Medical Research, Parkville Victoria 3052, Australia
- The Department of Medical Biology, University of Melbourne, Parkville, Victoria 3052, Australia
| | - David K. Chalmers
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville Victoria 3052, Australia
| | - Philip E. Thompson
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville Victoria 3052, Australia
| | - Ruby H. P. Law
- Department of Biochemistry and Molecular Biology and Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia
| | - Raymond S. Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville Victoria 3052, Australia
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21
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Brennan AJ, Law RHP, Conroy PJ, Noori T, Lukoyanova N, Saibil H, Yagita H, Ciccone A, Verschoor S, Whisstock JC, Trapani JA, Voskoboinik I. Perforin proteostasis is regulated through its C2 domain: supra-physiological cell death mediated by T431D-perforin. Cell Death Differ 2018; 25:1517-1529. [PMID: 29416110 DOI: 10.1038/s41418-018-0057-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 11/20/2017] [Accepted: 12/05/2017] [Indexed: 12/27/2022] Open
Abstract
The pore forming, Ca2+-dependent protein, perforin, is essential for the function of cytotoxic lymphocytes, which are at the frontline of immune defence against pathogens and cancer. Perforin is a glycoprotein stored in the secretory granules prior to release into the immune synapse. Congenital perforin deficiency causes fatal immune dysregulation, and is associated with various haematological malignancies. At least 50% of pathological missense mutations in perforin result in protein misfolding and retention in the endoplasmic reticulum. However, the regulation of perforin proteostasis remains unexplored. Using a variety of biochemical assays that assess protein stability and acquisition of complex glycosylation, we demonstrated that the binding of Ca2+ to the C2 domain stabilises perforin and regulates its export from the endoplasmic reticulum to the secretory granules. As perforin is a thermo-labile protein, we hypothesised that by altering its C2 domain it may be possible to improve protein stability. On the basis of the X-ray crystal structure of the perforin C2 domain, we designed a mutation (T431D) in the Ca2+ binding loop. Mutant perforin displayed markedly enhanced thermal stability and lytic function, despite its trafficking from the endoplasmic reticulum remaining unchanged. Furthermore, by introducing the T431D mutation into A90V perforin, a pathogenic mutation, which results in protein misfolding, we corrected the A90V folding defect and completely restored perforin's cytotoxic function. These results revealed an unexpected role for the Ca2+-dependent C2 domain in maintaining perforin proteostasis and demonstrated the possibility of designing perforin with supra-physiological cytotoxic function through stabilisation of the C2 domain.
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Affiliation(s)
- Amelia J Brennan
- Killer Cell Biology Laboratory, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia.
| | - Ruby H P Law
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, VIC, Australia.,The ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Melbourne, VIC, Australia
| | - Paul J Conroy
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, VIC, Australia.,The ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Melbourne, VIC, Australia
| | - Tahereh Noori
- Killer Cell Biology Laboratory, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - Natalya Lukoyanova
- Department of Crystallography/Biological Sciences, Institute of Structural and Molecular Biology, Birkbeck College, London, UK
| | - Helen Saibil
- Department of Crystallography/Biological Sciences, Institute of Structural and Molecular Biology, Birkbeck College, London, UK
| | - Hideo Yagita
- Department of Immunology, Juntendo University School of Medicine, Tokyo, 113-8421, Japan
| | - Annette Ciccone
- Cancer Cell Death Laboratory, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - Sandra Verschoor
- Cancer Cell Death Laboratory, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - James C Whisstock
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, VIC, Australia.,The ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Melbourne, VIC, Australia
| | - Joseph A Trapani
- Cancer Cell Death Laboratory, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, VIC, Australia
| | - Ilia Voskoboinik
- Killer Cell Biology Laboratory, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia. .,Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, VIC, Australia.
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22
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Teoh SSY, Vieusseux J, Prakash M, Berkowicz S, Luu J, Bird CH, Law RHP, Rosado C, Price JT, Whisstock JC, Bird PI. Maspin is not required for embryonic development or tumour suppression. Nat Commun 2016; 5:3164. [PMID: 24445777 PMCID: PMC3905777 DOI: 10.1038/ncomms4164] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Accepted: 12/20/2013] [Indexed: 02/07/2023] Open
Abstract
Maspin (SERPINB5) is accepted as an important tumour suppressor lost in many cancers. Consistent with a critical role in development or differentiation maspin knockout mice die during early embryogenesis, yet clinical data conflict on the prognostic utility of maspin expression. Here to reconcile these findings we made conditional knockout mice. Surprisingly, maspin knockout embryos develop into overtly normal animals. Contrary to original reports, maspin re-expression does not inhibit tumour growth or metastasis in vivo, or influence cell migration, invasion or survival in vitro. Bioinformatic analyses reveal that maspin is not commonly under-expressed in cancer, and that perturbation of genes near maspin may in fact explain poor survival in certain patient cohorts with low maspin expression. A role for the serpin maspin has been described in both development and cancer. In this study, the authors demonstrate that maspin knockout mice develop normally and that maspin does not function as a tumour suppressor, suggesting that another gene at the maspin locus may be responsible for this activity.
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Affiliation(s)
- Sonia S Y Teoh
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Victoria 3800, Australia
| | - Jessica Vieusseux
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Victoria 3800, Australia
| | - Monica Prakash
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Victoria 3800, Australia
| | - Susan Berkowicz
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Victoria 3800, Australia
| | - Jennii Luu
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Victoria 3800, Australia
| | - Catherina H Bird
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Victoria 3800, Australia
| | - Ruby H P Law
- 1] Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Victoria 3800, Australia [2] Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, School of Biomedical Sciences, Monash University, Victoria 3800, Australia
| | - Carlos Rosado
- 1] Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Victoria 3800, Australia [2] Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, School of Biomedical Sciences, Monash University, Victoria 3800, Australia
| | - John T Price
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Victoria 3800, Australia
| | - James C Whisstock
- 1] Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Victoria 3800, Australia [2] Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, School of Biomedical Sciences, Monash University, Victoria 3800, Australia
| | - Phillip I Bird
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Victoria 3800, Australia
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23
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Dudkina NV, Spicer BA, Reboul CF, Conroy PJ, Lukoyanova N, Elmlund H, Law RHP, Ekkel SM, Kondos SC, Goode RJA, Ramm G, Whisstock JC, Saibil HR, Dunstone MA. Structure of the poly-C9 component of the complement membrane attack complex. Nat Commun 2016; 7:10588. [PMID: 26841934 PMCID: PMC4742998 DOI: 10.1038/ncomms10588] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 12/31/2015] [Indexed: 12/11/2022] Open
Abstract
The membrane attack complex (MAC)/perforin-like protein complement component 9 (C9) is the major component of the MAC, a multi-protein complex that forms pores in the membrane of target pathogens. In contrast to homologous proteins such as perforin and the cholesterol-dependent cytolysins (CDCs), all of which require the membrane for oligomerisation, C9 assembles directly onto the nascent MAC from solution. However, the molecular mechanism of MAC assembly remains to be understood. Here we present the 8 Å cryo-EM structure of a soluble form of the poly-C9 component of the MAC. These data reveal a 22-fold symmetrical arrangement of C9 molecules that yield an 88-strand pore-forming β-barrel. The N-terminal thrombospondin-1 (TSP1) domain forms an unexpectedly extensive part of the oligomerisation interface, thus likely facilitating solution-based assembly. These TSP1 interactions may also explain how additional C9 subunits can be recruited to the growing MAC subsequent to membrane insertion.
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Affiliation(s)
- Natalya V. Dudkina
- Department of Crystallography, Institute of Structural and Molecular Biology, Birkbeck College, London WC1E 7HX, UK
| | - Bradley A. Spicer
- ARC Centre of Excellence in Advanced Molecular Imaging, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
| | - Cyril F. Reboul
- ARC Centre of Excellence in Advanced Molecular Imaging, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
| | - Paul J. Conroy
- ARC Centre of Excellence in Advanced Molecular Imaging, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
| | - Natalya Lukoyanova
- Department of Crystallography, Institute of Structural and Molecular Biology, Birkbeck College, London WC1E 7HX, UK
| | - Hans Elmlund
- ARC Centre of Excellence in Advanced Molecular Imaging, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
| | - Ruby H. P. Law
- ARC Centre of Excellence in Advanced Molecular Imaging, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
| | - Susan M. Ekkel
- ARC Centre of Excellence in Advanced Molecular Imaging, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
| | - Stephanie C. Kondos
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
| | - Robert J. A. Goode
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
| | - Georg Ramm
- ARC Centre of Excellence in Advanced Molecular Imaging, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
| | - James C. Whisstock
- ARC Centre of Excellence in Advanced Molecular Imaging, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
| | - Helen R. Saibil
- Department of Crystallography, Institute of Structural and Molecular Biology, Birkbeck College, London WC1E 7HX, UK
| | - Michelle A. Dunstone
- ARC Centre of Excellence in Advanced Molecular Imaging, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Clayton Campus, Monash University, Melbourne, Victoria 3800, Australia
- Department of Microbiology, Biomedicine Discovery Institute, Clayton Campus, Monash University, Melbourne, 3800 Victoria, Australia
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24
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Yagi H, Conroy PJ, Leung EWW, Law RHP, Trapani JA, Voskoboinik I, Whisstock JC, Norton RS. Structural Basis for Ca2+-mediated Interaction of the Perforin C2 Domain with Lipid Membranes. J Biol Chem 2015; 290:25213-26. [PMID: 26306037 DOI: 10.1074/jbc.m115.668384] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Indexed: 11/06/2022] Open
Abstract
Natural killer cells and cytotoxic T-lymphocytes deploy perforin and granzymes to kill infected host cells. Perforin, secreted by immune cells, binds target membranes to form pores that deliver pro-apoptotic granzymes into the target cell. A crucial first step in this process is interaction of its C2 domain with target cell membranes, which is a calcium-dependent event. Some aspects of this process are understood, but many molecular details remain unclear. To address this, we investigated the mechanism of Ca(2+) and lipid binding to the C2 domain by NMR spectroscopy and x-ray crystallography. Calcium titrations, together with dodecylphosphocholine micelle experiments, confirmed that multiple Ca(2+) ions bind within the calcium-binding regions, activating perforin with respect to membrane binding. We have also determined the affinities of several of these binding sites and have shown that this interaction causes a significant structural rearrangement in CBR1. Thus, it is proposed that Ca(2+) binding at the weakest affinity site triggers changes in the C2 domain that facilitate its interaction with lipid membranes.
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Affiliation(s)
- Hiromasa Yagi
- From the Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052
| | - Paul J Conroy
- the Department of Biochemistry and Molecular Biology and ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800
| | - Eleanor W W Leung
- From the Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052
| | - Ruby H P Law
- the Department of Biochemistry and Molecular Biology and ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800
| | - Joseph A Trapani
- the Cancer Immunology Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria 3002, and the Departments of Microbiology and Immunology and
| | - Ilia Voskoboinik
- the Cancer Immunology Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria 3002, and the Departments of Microbiology and Immunology and Genetics and Pathology, University of Melbourne, Parkville, Victoria 3052, Australia
| | - James C Whisstock
- the Department of Biochemistry and Molecular Biology and ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800,
| | - Raymond S Norton
- From the Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052,
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25
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De Oliveira DMP, Law RHP, Ly D, Cook SM, Quek AJ, McArthur JD, Whisstock JC, Sanderson-Smith ML. Preferential Acquisition and Activation of Plasminogen Glycoform II by PAM Positive Group A Streptococcal Isolates. Biochemistry 2015; 54:3960-8. [PMID: 26029848 DOI: 10.1021/acs.biochem.5b00130] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Plasminogen (Plg) circulates in the host as two predominant glycoforms. Glycoform I Plg (GI-Plg) contains glycosylation sites at Asn289 and Thr346, whereas glycoform II Plg (GII-Plg) is exclusively glycosylated at Thr346. Surface plasmon resonance experiments demonstrated that Plg binding group A streptococcal M protein (PAM) exhibits comparative equal affinity for GI- and GII-Plg in the "closed" conformation (for GII-Plg, KD = 27.4 nM; for GI-Plg, KD = 37.0 nM). When Plg was in the "open" conformation, PAM exhibited an 11-fold increase in affinity for GII-Plg (KD = 2.8 nM) compared with that for GI-Plg (KD = 33.2 nM). The interaction of PAM with Plg is believed to be mediated by lysine binding sites within kringle (KR) 2 of Plg. PAM-GI-Plg interactions were fully inhibited with 100 mM lysine analogue ε-aminocaproic acid (εACA), whereas PAM-GII-Plg interactions were shown to be weakened but not inhibited in the presence of 400 mM εACA. In contrast, binding to the KR1-3 domains of GII-Plg (angiostatin) by PAM was completely inhibited in the presence 5 mM εACA. Along with PAM, emm pattern D GAS isolates express a phenotypically distinct SK variant (type 2b SK) that requires Plg ligands such as PAM to activate Plg. Type 2b SK was able to generate an active site and activate GII-Plg at a rate significantly higher than that of GI-Plg when bound to PAM. Taken together, these data suggest that GAS selectively recruits and activates GII-Plg. Furthermore, we propose that the interaction between PAM and Plg may be partially mediated by a secondary binding site outside of KR2, affected by glycosylation at Asn289.
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Affiliation(s)
- David M P De Oliveira
- †Illawarra Health and Medical Research Institute, School of Biological Sciences, University of Wollongong, Wollongong 2522, Australia
| | - Ruby H P Law
- ‡Department of Biochemistry and Molecular Biology, Monash University, Melbourne 3168, Australia
| | - Diane Ly
- †Illawarra Health and Medical Research Institute, School of Biological Sciences, University of Wollongong, Wollongong 2522, Australia
| | - Simon M Cook
- †Illawarra Health and Medical Research Institute, School of Biological Sciences, University of Wollongong, Wollongong 2522, Australia
| | - Adam J Quek
- ‡Department of Biochemistry and Molecular Biology, Monash University, Melbourne 3168, Australia
| | - Jason D McArthur
- †Illawarra Health and Medical Research Institute, School of Biological Sciences, University of Wollongong, Wollongong 2522, Australia
| | - James C Whisstock
- ‡Department of Biochemistry and Molecular Biology, Monash University, Melbourne 3168, Australia
| | - Martina L Sanderson-Smith
- †Illawarra Health and Medical Research Institute, School of Biological Sciences, University of Wollongong, Wollongong 2522, Australia
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26
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Cork AJ, Ericsson DJ, Law RHP, Casey LW, Valkov E, Bertozzi C, Stamp A, Jovcevski B, Aquilina JA, Whisstock JC, Walker MJ, Kobe B. Stability of the octameric structure affects plasminogen-binding capacity of streptococcal enolase. PLoS One 2015; 10:e0121764. [PMID: 25807546 PMCID: PMC4373793 DOI: 10.1371/journal.pone.0121764] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 02/11/2015] [Indexed: 11/19/2022] Open
Abstract
Group A Streptococcus (GAS) is a human pathogen that has the potential to cause invasive disease by binding and activating human plasmin(ogen). Streptococcal surface enolase (SEN) is an octameric α-enolase that is localized at the GAS cell surface. In addition to its glycolytic role inside the cell, SEN functions as a receptor for plasmin(ogen) on the bacterial surface, but the understanding of the molecular basis of plasmin(ogen) binding is limited. In this study, we determined the crystal and solution structures of GAS SEN and characterized the increased plasminogen binding by two SEN mutants. The plasminogen binding ability of SENK312A and SENK362A is ~2- and ~3.4-fold greater than for the wild-type protein. A combination of thermal stability assays, native mass spectrometry and X-ray crystallography approaches shows that increased plasminogen binding ability correlates with decreased stability of the octamer. We propose that decreased stability of the octameric structure facilitates the access of plasmin(ogen) to its binding sites, leading to more efficient plasmin(ogen) binding and activation.
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Affiliation(s)
- Amanda J. Cork
- School of Chemistry and Molecular Biosciences and Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, 4072, Australia
- Australian Infectious Disease Research Centre, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Daniel J. Ericsson
- School of Chemistry and Molecular Biosciences and Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, 4072, Australia
- Australian Infectious Disease Research Centre, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Ruby H. P. Law
- Department of Biochemistry and Molecular Biology and the ARC Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Melbourne, VIC, 3800, Australia
| | - Lachlan W. Casey
- School of Chemistry and Molecular Biosciences and Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Eugene Valkov
- School of Chemistry and Molecular Biosciences and Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Carlo Bertozzi
- School of Chemistry and Molecular Biosciences and Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Anna Stamp
- School of Chemistry and Molecular Biosciences and Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Blagojce Jovcevski
- School of Biological Sciences and Illawarra Health and Medical Research, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - J. Andrew Aquilina
- School of Biological Sciences and Illawarra Health and Medical Research, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - James C. Whisstock
- Department of Biochemistry and Molecular Biology and the ARC Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Melbourne, VIC, 3800, Australia
| | - Mark J. Walker
- School of Chemistry and Molecular Biosciences and Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, 4072, Australia
- Australian Infectious Disease Research Centre, University of Queensland, Brisbane, QLD, 4072, Australia
- * E-mail: (BK); (MJW)
| | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences and Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, 4072, Australia
- Australian Infectious Disease Research Centre, University of Queensland, Brisbane, QLD, 4072, Australia
- * E-mail: (BK); (MJW)
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27
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Conroy PJ, Law RHP, Gilgunn S, Hearty S, Caradoc-Davies TT, Lloyd G, O'Kennedy RJ, Whisstock JC. Reconciling the structural attributes of avian antibodies. J Biol Chem 2014; 289:15384-92. [PMID: 24737329 DOI: 10.1074/jbc.m114.562470] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Antibodies are high value therapeutic, diagnostic, biotechnological, and research tools. Combinatorial approaches to antibody discovery have facilitated access to unique antibodies by surpassing the diversity limitations of the natural repertoire, exploitation of immune repertoires from multiple species, and tailoring selections to isolate antibodies with desirable biophysical attributes. The V-gene repertoire of the chicken does not utilize highly diverse sequence and structures, which is in stark contrast to the mechanism employed by humans, mice, and primates. Recent exploitation of the avian immune system has generated high quality, high affinity antibodies to a wide range of antigens for a number of therapeutic, diagnostic and biotechnological applications. Furthermore, extensive examination of the amino acid characteristics of the chicken repertoire has provided significant insight into mechanisms employed by the avian immune system. A paucity of avian antibody crystal structures has limited our understanding of the structural consequences of these uniquely chicken features. This paper presents the crystal structure of two chicken single chain fragment variable (scFv) antibodies generated from large libraries by phage display against important human antigen targets, which capture two unique CDRL1 canonical classes in the presence and absence of a non-canonical disulfide constrained CDRH3. These structures cast light on the unique structural features of chicken antibodies and contribute further to our collective understanding of the unique mechanisms of diversity and biochemical attributes that render the chicken repertoire of particular value for antibody generation.
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Affiliation(s)
- Paul J Conroy
- From the Department of Biochemistry and Molecular Biology, Faculty of Medicine, Nursing and Health Science, Monash University, Melbourne, Victoria 3800, Australia
| | - Ruby H P Law
- From the Department of Biochemistry and Molecular Biology, Faculty of Medicine, Nursing and Health Science, Monash University, Melbourne, Victoria 3800, Australia
| | - Sarah Gilgunn
- School of Biotechnology, Dublin City University, Dublin 9, Ireland
| | - Stephen Hearty
- Biomedical Diagnostics Institute, National Centre for Sensor Research, Dublin City University, Dublin 9, Ireland, and
| | - Tom T Caradoc-Davies
- Australian Synchrotron, 800 Blackburn Road, Clayton, Melbourne, Victoria 3168, Australia
| | - Gordon Lloyd
- From the Department of Biochemistry and Molecular Biology, Faculty of Medicine, Nursing and Health Science, Monash University, Melbourne, Victoria 3800, Australia
| | - Richard J O'Kennedy
- School of Biotechnology, Dublin City University, Dublin 9, Ireland, Biomedical Diagnostics Institute, National Centre for Sensor Research, Dublin City University, Dublin 9, Ireland, and
| | - James C Whisstock
- From the Department of Biochemistry and Molecular Biology, Faculty of Medicine, Nursing and Health Science, Monash University, Melbourne, Victoria 3800, Australia,
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28
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Linke C, Siemens N, Oehmcke S, Radjainia M, Law RHP, Whisstock JC, Baker EN, Kreikemeyer B. The extracellular protein factor Epf from Streptococcus pyogenes is a cell surface adhesin that binds to cells through an N-terminal domain containing a carbohydrate-binding module. J Biol Chem 2012; 287:38178-89. [PMID: 22977243 PMCID: PMC3488087 DOI: 10.1074/jbc.m112.376434] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Revised: 09/07/2012] [Indexed: 01/19/2023] Open
Abstract
Streptococcus pyogenes is an exclusively human pathogen. Streptococcal attachment to and entry into epithelial cells is a prerequisite for a successful infection of the human host and requires adhesins. Here, we demonstrate that the multidomain protein Epf from S. pyogenes serotype M49 is a streptococcal adhesin. An epf-deficient mutant showed significantly decreased adhesion to and internalization into human keratinocytes. Cell adhesion is mediated by the N-terminal domain of Epf (EpfN) and increased by the human plasma protein plasminogen. The crystal structure of EpfN, solved at 1.6 Å resolution, shows that it consists of two subdomains: a carbohydrate-binding module and a fibronectin type III domain. Both fold types commonly participate in ligand receptor and protein-protein interactions. EpfN is followed by 18 repeats of a domain classified as DUF1542 (domain of unknown function 1542) and a C-terminal cell wall sorting signal. The DUF1542 repeats are not involved in adhesion, but biophysical studies show they are predominantly α-helical and form a fiber-like stalk of tandem DUF1542 domains. Epf thus conforms with the widespread family of adhesins known as MSCRAMMs (microbial surface components recognizing adhesive matrix molecules), in which a cell wall-attached stalk enables long range interactions via its adhesive N-terminal domain.
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MESH Headings
- Adhesins, Bacterial/chemistry
- Adhesins, Bacterial/genetics
- Adhesins, Bacterial/metabolism
- Bacterial Adhesion/genetics
- Binding Sites/genetics
- Carbohydrates/chemistry
- Carcinoma, Squamous Cell/metabolism
- Carcinoma, Squamous Cell/microbiology
- Carcinoma, Squamous Cell/pathology
- Cell Line
- Cell Line, Tumor
- Crystallography, X-Ray
- Humans
- Keratinocytes/cytology
- Keratinocytes/metabolism
- Keratinocytes/microbiology
- Models, Molecular
- Mutation
- Plasminogen/chemistry
- Plasminogen/metabolism
- Protein Binding
- Protein Structure, Tertiary
- Scattering, Small Angle
- Streptococcus pyogenes/genetics
- Streptococcus pyogenes/metabolism
- Surface Plasmon Resonance
- X-Ray Diffraction
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Affiliation(s)
- Christian Linke
- From the Maurice Wilkins Centre for Molecular Biodiscovery and School of Biological Sciences, University of Auckland, Auckland 1142, New Zealand
| | - Nikolai Siemens
- the Institute of Medical Microbiology, Virology and Hygiene, Rostock University Hospital, 18057 Rostock, Germany, and
| | - Sonja Oehmcke
- the Institute of Medical Microbiology, Virology and Hygiene, Rostock University Hospital, 18057 Rostock, Germany, and
| | - Mazdak Radjainia
- From the Maurice Wilkins Centre for Molecular Biodiscovery and School of Biological Sciences, University of Auckland, Auckland 1142, New Zealand
| | - Ruby H. P. Law
- the Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - James C. Whisstock
- the Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - Edward N. Baker
- From the Maurice Wilkins Centre for Molecular Biodiscovery and School of Biological Sciences, University of Auckland, Auckland 1142, New Zealand
| | - Bernd Kreikemeyer
- the Institute of Medical Microbiology, Virology and Hygiene, Rostock University Hospital, 18057 Rostock, Germany, and
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Lu BGC, Sofian T, Law RHP, Coughlin PB, Horvath AJ. Contribution of conserved lysine residues in the alpha2-antiplasmin C terminus to plasmin binding and inhibition. J Biol Chem 2011; 286:24544-52. [PMID: 21543325 DOI: 10.1074/jbc.m111.229013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
α(2)-Antiplasmin is the physiological inhibitor of plasmin and is unique in the serpin family due to N- and C-terminal extensions beyond its core domain. The C-terminal extension comprises 55 amino acids from Asn-410 to Lys-464, and the lysine residues (Lys-418, Lys-427, Lys-434, Lys-441, Lys-448, and Lys-464) within this region are important in mediating the initial interaction with kringle domains of plasmin. To understand the role of lysine residues within the C terminus of α(2)-antiplasmin, we systematically and sequentially mutated the C-terminal lysines, studied the effects on the rate of plasmin inhibition, and measured the binding affinity for plasmin via surface plasmon resonance. We determined that the C-terminal lysine (Lys-464) is individually most important in initiating binding to plasmin. Using two independent methods, we also showed that the conserved internal lysine residues play a major role mediating binding of the C terminus of α(2)-antiplasmin to kringle domains of plasmin and in accelerating the rate of interaction between α(2)-antiplasmin and plasmin. When the C terminus of α(2)-antiplasmin was removed, the binding affinity for active site-blocked plasmin remained high, suggesting additional exosite interactions between the serpin core and plasmin.
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Affiliation(s)
- Bernadine G C Lu
- Australian Centre for Blood Diseases, Monash University, Melbourne, Victoria 3004, Australia
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30
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Kennan RM, Wong W, Dhungyel OP, Han X, Wong D, Parker D, Rosado CJ, Law RHP, McGowan S, Reeve SB, Levina V, Powers GA, Pike RN, Bottomley SP, Smith AI, Marsh I, Whittington RJ, Whisstock JC, Porter CJ, Rood JI. The subtilisin-like protease AprV2 is required for virulence and uses a novel disulphide-tethered exosite to bind substrates. PLoS Pathog 2010; 6:e1001210. [PMID: 21124876 PMCID: PMC2991261 DOI: 10.1371/journal.ppat.1001210] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2010] [Accepted: 10/26/2010] [Indexed: 11/18/2022] Open
Abstract
Many bacterial pathogens produce extracellular proteases that degrade the extracellular matrix of the host and therefore are involved in disease pathogenesis. Dichelobacter nodosus is the causative agent of ovine footrot, a highly contagious disease that is characterized by the separation of the hoof from the underlying tissue. D. nodosus secretes three subtilisin-like proteases whose analysis forms the basis of diagnostic tests that differentiate between virulent and benign strains and have been postulated to play a role in virulence. We have constructed protease mutants of D. nodosus; their analysis in a sheep virulence model revealed that one of these enzymes, AprV2, was required for virulence. These studies challenge the previous hypothesis that the elastase activity of AprV2 is important for disease progression, since aprV2 mutants were virulent when complemented with aprB2, which encodes a variant that has impaired elastase activity. We have determined the crystal structures of both AprV2 and AprB2 and characterized the biological activity of these enzymes. These data reveal that an unusual extended disulphide-tethered loop functions as an exosite, mediating effective enzyme-substrate interactions. The disulphide bond and Tyr92, which was located at the exposed end of the loop, were functionally important. Bioinformatic analyses suggested that other pathogenic bacteria may have proteases that utilize a similar mechanism. In conclusion, we have used an integrated multidisciplinary combination of bacterial genetics, whole animal virulence trials in the original host, biochemical studies, and comprehensive analysis of crystal structures to provide the first definitive evidence that the extracellular secreted proteases produced by D. nodosus are required for virulence and to elucidate the molecular mechanism by which these proteases bind to their natural substrates. We postulate that this exosite mechanism may be used by proteases produced by other bacterial pathogens of both humans and animals.
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Affiliation(s)
- Ruth M. Kennan
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria, Australia
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Wilson Wong
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Om P. Dhungyel
- Faculty of Veterinary Science, University of Sydney, Camden, New South Wales, Australia
| | - Xiaoyan Han
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria, Australia
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - David Wong
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria, Australia
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Dane Parker
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria, Australia
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Carlos J. Rosado
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Ruby H. P. Law
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Sheena McGowan
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Shane B. Reeve
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Vita Levina
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Glenn A. Powers
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Robert N. Pike
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Stephen P. Bottomley
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - A. Ian Smith
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Ian Marsh
- Elizabeth Macarthur Agricultural Institute, NSW Department of Primary Industries, Camden, New South Wales, Australia
| | - Richard J. Whittington
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria, Australia
- Faculty of Veterinary Science, University of Sydney, Camden, New South Wales, Australia
| | - James C. Whisstock
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Corrine J. Porter
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
- * E-mail: (CJP); (JIR)
| | - Julian I. Rood
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria, Australia
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
- * E-mail: (CJP); (JIR)
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Kondos SC, Hatfaludi T, Voskoboinik I, Trapani JA, Law RHP, Whisstock JC, Dunstone MA. The structure and function of mammalian membrane-attack complex/perforin-like proteins. ACTA ACUST UNITED AC 2010; 76:341-51. [PMID: 20860583 DOI: 10.1111/j.1399-0039.2010.01566.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The membrane-attack complex (MAC) of complement pathway and perforin (PF) are important tools deployed by the immune system to target pathogens. Both perforin and the C9 component of the MAC contain a common 'MACPF' domain and form pores in the cell membrane as part of their function. The MAC targets gram-negative bacteria and certain pathogenic parasites, while perforin, released by natural killer cells or cytotoxic T lymphocytes (CTLs), targets virus-infected and transformed host cells (1). Remarkably, recent structural studies show that the MACPF domain is homologous to the pore-forming portion of bacterial cholesterol-dependent cytolysins; these data have provided important insight into the mechanism of pore-forming MACPF proteins. In addition to their role in immunity, MACPF family members have been identified as animal venoms, factors required for pathogen migration across host cell membranes and factors that govern developmental processes such as embryonic patterning and neuronal guidance (2). While most MACPF proteins characterized to date either form pores or span lipid membranes, some do not (e.g. the C6 component of the MAC). A current challenge is thus to understand the role, pore forming or otherwise, of MACPF proteins in developmental biology. This review discusses structural and functional diversity of the mammalian MACPF proteins.
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Affiliation(s)
- S C Kondos
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
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32
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Nogues C, Leh H, Langendorf CG, Law RHP, Buckle AM, Buckle M. Characterisation of peptide microarrays for studying antibody-antigen binding using surface plasmon resonance imagery. PLoS One 2010; 5:e12152. [PMID: 20730101 PMCID: PMC2921342 DOI: 10.1371/journal.pone.0012152] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2010] [Accepted: 07/19/2010] [Indexed: 12/01/2022] Open
Abstract
Background Non-specific binding to biosensor surfaces is a major obstacle to quantitative analysis of selective retention of analytes at immobilized target molecules. Although a range of chemical antifouling monolayers has been developed to address this problem, many macromolecular interactions still remain refractory to analysis due to the prevalent high degree of non-specific binding. We describe how we use the dynamic process of the formation of self assembling monolayers and optimise physical and chemical properties thus reducing considerably non-specific binding and allowing analysis of specific binding of analytes to immobilized target molecules. Methodology/Principal Findings We illustrate this approach by the production of specific protein arrays for the analysis of interactions between the 65kDa isoform of human glutamate decarboxylase (GAD65) and a human monoclonal antibody. Our data illustrate that we have effectively eliminated non-specific interactions with the surface containing the immobilised GAD65 molecules. The findings have several implications. First, this approach obviates the dubious process of background subtraction and gives access to more accurate kinetic and equilibrium values that are no longer contaminated by multiphase non-specific binding. Second, an enhanced signal to noise ratio increases not only the sensitivity but also confidence in the use of SPR to generate kinetic constants that may then be inserted into van't Hoff type analyses to provide comparative ΔG, ΔS and ΔH values, making this an efficient, rapid and competitive alternative to ITC measurements used in drug and macromolecular-interaction mechanistic studies. Third, the accuracy of the measurements allows the application of more intricate interaction models than simple Langmuir monophasic binding. Conclusions The detection and measurement of antibody binding by the type 1 diabetes autoantigen GAD65 represents an example of an antibody-antigen interaction where good structural, mechanistic and immunological data are available. Using SPRi we were able to characterise the kinetics of the interaction in greater detail than ELISA/RIA methods. Furthermore, our data indicate that SPRi is well suited to a multiplexed immunoassay using GAD65 proteins, and may be applicable to other biomarkers.
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Affiliation(s)
- Claude Nogues
- Dynamics of Macromolecular Complexes, Laboratoire de Biologie et Pharmacologie Appliquée, UMR 8113 du CNRS, Institut d'Alembert, Ecole Normale Supérieure de Cachan, Cachan, France
| | - Hervé Leh
- Dynamics of Macromolecular Complexes, Laboratoire de Biologie et Pharmacologie Appliquée, UMR 8113 du CNRS, Institut d'Alembert, Ecole Normale Supérieure de Cachan, Cachan, France
| | | | - Ruby H. P. Law
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Ashley M. Buckle
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
- * E-mail: (AMB); (MB)
| | - Malcolm Buckle
- Dynamics of Macromolecular Complexes, Laboratoire de Biologie et Pharmacologie Appliquée, UMR 8113 du CNRS, Institut d'Alembert, Ecole Normale Supérieure de Cachan, Cachan, France
- * E-mail: (AMB); (MB)
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33
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Langendorf CG, Key TLG, Fenalti G, Kan WT, Buckle AM, Caradoc-Davies T, Tuck KL, Law RHP, Whisstock JC. The X-ray crystal structure of Escherichia coli succinic semialdehyde dehydrogenase; structural insights into NADP+/enzyme interactions. PLoS One 2010; 5:e9280. [PMID: 20174634 PMCID: PMC2823781 DOI: 10.1371/journal.pone.0009280] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2009] [Accepted: 01/23/2010] [Indexed: 01/14/2023] Open
Abstract
Background In mammals succinic semialdehyde dehydrogenase (SSADH) plays an essential role in the metabolism of the inhibitory neurotransmitter γ-aminobutyric acid (GABA) to succinic acid (SA). Deficiency of SSADH in humans results in elevated levels of GABA and γ-Hydroxybutyric acid (GHB), which leads to psychomotor retardation, muscular hypotonia, non-progressive ataxia and seizures. In Escherichia coli, two genetically distinct forms of SSADHs had been described that are essential for preventing accumulation of toxic levels of succinic semialdehyde (SSA) in cells. Methodology/Principal Findings Here we structurally characterise SSADH encoded by the E coli gabD gene by X-ray crystallographic studies and compare these data with the structure of human SSADH. In the E. coli SSADH structure, electron density for the complete NADP+ cofactor in the binding sites is clearly evident; these data in particular revealing how the nicotinamide ring of the cofactor is positioned in each active site. Conclusions/Significance Our structural data suggest that a deletion of three amino acids in E. coli SSADH permits this enzyme to use NADP+, whereas in contrast the human enzyme utilises NAD+. Furthermore, the structure of E. coli SSADH gives additional insight into human mutations that result in disease.
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Affiliation(s)
- Christopher G. Langendorf
- Department of Biochemistry and Molecular Biology, Monash University, Clayton Campus, Melbourne, Victoria, Australia
| | - Trevor L. G. Key
- Department of Biochemistry and Molecular Biology, Monash University, Clayton Campus, Melbourne, Victoria, Australia
- School of Chemistry, Monash University, Clayton Campus, Melbourne, Victoria, Australia
| | - Gustavo Fenalti
- Department of Biochemistry and Molecular Biology, Monash University, Clayton Campus, Melbourne, Victoria, Australia
- Department of Molecular Biology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Wan-Ting Kan
- Department of Biochemistry and Molecular Biology, Monash University, Clayton Campus, Melbourne, Victoria, Australia
- ARC Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Melbourne, Victoria, Australia
| | - Ashley M. Buckle
- Department of Biochemistry and Molecular Biology, Monash University, Clayton Campus, Melbourne, Victoria, Australia
| | | | - Kellie L. Tuck
- School of Chemistry, Monash University, Clayton Campus, Melbourne, Victoria, Australia
| | - Ruby H. P. Law
- Department of Biochemistry and Molecular Biology, Monash University, Clayton Campus, Melbourne, Victoria, Australia
- ARC Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Melbourne, Victoria, Australia
- * E-mail: (RHPL); (JCW)
| | - James C. Whisstock
- Department of Biochemistry and Molecular Biology, Monash University, Clayton Campus, Melbourne, Victoria, Australia
- ARC Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Melbourne, Victoria, Australia
- * E-mail: (RHPL); (JCW)
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Song J, Tan H, Mahmood K, Law RHP, Buckle AM, Webb GI, Akutsu T, Whisstock JC. Prodepth: predict residue depth by support vector regression approach from protein sequences only. PLoS One 2009; 4:e7072. [PMID: 19759917 PMCID: PMC2742725 DOI: 10.1371/journal.pone.0007072] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2009] [Accepted: 08/20/2009] [Indexed: 11/24/2022] Open
Abstract
Residue depth (RD) is a solvent exposure measure that complements the information provided by conventional accessible surface area (ASA) and describes to what extent a residue is buried in the protein structure space. Previous studies have established that RD is correlated with several protein properties, such as protein stability, residue conservation and amino acid types. Accurate prediction of RD has many potentially important applications in the field of structural bioinformatics, for example, facilitating the identification of functionally important residues, or residues in the folding nucleus, or enzyme active sites from sequence information. In this work, we introduce an efficient approach that uses support vector regression to quantify the relationship between RD and protein sequence. We systematically investigated eight different sequence encoding schemes including both local and global sequence characteristics and examined their respective prediction performances. For the objective evaluation of our approach, we used 5-fold cross-validation to assess the prediction accuracies and showed that the overall best performance could be achieved with a correlation coefficient (CC) of 0.71 between the observed and predicted RD values and a root mean square error (RMSE) of 1.74, after incorporating the relevant multiple sequence features. The results suggest that residue depth could be reliably predicted solely from protein primary sequences: local sequence environments are the major determinants, while global sequence features could influence the prediction performance marginally. We highlight two examples as a comparison in order to illustrate the applicability of this approach. We also discuss the potential implications of this new structural parameter in the field of protein structure prediction and homology modeling. This method might prove to be a powerful tool for sequence analysis.
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Affiliation(s)
- Jiangning Song
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria, Australia
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto, Japan
- * E-mail: (JS); (JCW)
| | - Hao Tan
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria, Australia
| | - Khalid Mahmood
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria, Australia
- ARC Centre of Excellence for Structural and Functional Microbial Genomics, Monash University, Clayton, Melbourne, Victoria, Australia
| | - Ruby H. P. Law
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria, Australia
| | - Ashley M. Buckle
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria, Australia
| | - Geoffrey I. Webb
- Faculty of Information Technology, Monash University, Clayton, Melbourne, Victoria, Australia
| | - Tatsuya Akutsu
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto, Japan
| | - James C. Whisstock
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria, Australia
- ARC Centre of Excellence for Structural and Functional Microbial Genomics, Monash University, Clayton, Melbourne, Victoria, Australia
- * E-mail: (JS); (JCW)
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35
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Fischer K, Langendorf CG, Irving JA, Reynolds S, Willis C, Beckham S, Law RHP, Yang S, Bashtannyk-Puhalovich TA, McGowan S, Whisstock JC, Pike RN, Kemp DJ, Buckle AM. Structural mechanisms of inactivation in scabies mite serine protease paralogues. J Mol Biol 2009; 390:635-45. [PMID: 19427318 DOI: 10.1016/j.jmb.2009.04.082] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2009] [Revised: 04/28/2009] [Accepted: 04/30/2009] [Indexed: 10/20/2022]
Abstract
The scabies mite (Sarcoptes scabiei) is a parasite responsible for major morbidity in disadvantaged communities and immuno-compromised patients worldwide. In addition to the physical discomfort caused by the disease, scabies infestations facilitate infection by Streptococcal species via skin lesions, resulting in a high prevalence of rheumatic fever/heart disease in affected communities. The scabies mite produces 33 proteins that are closely related to those in the dust mite group 3 allergen and belong to the S1-like protease family (chymotrypsin-like). However, all but one of these molecules contain mutations in the conserved active-site catalytic triad that are predicted to render them catalytically inactive. These molecules are thus termed scabies mite inactivated protease paralogues (SMIPPs). The precise function of SMIPPs is unclear; however, it has been suggested that these proteins might function by binding and protecting target substrates from cleavage by host immune proteases, thus preventing the host from mounting an effective immune challenge. In order to begin to understand the structural basis for SMIPP function, we solved the crystal structures of SMIPP-S-I1 and SMIPP-S-D1 at 1.85 A and 2.0 A resolution, respectively. Both structures adopt the characteristic serine protease fold, albeit with large structural variations over much of the molecule. In both structures, mutations in the catalytic triad together with occlusion of the S1 subsite by a conserved Tyr200 residue is predicted to block substrate ingress. Accordingly, we show that both proteases lack catalytic function. Attempts to restore function (via site-directed mutagenesis of catalytic residues as well as Tyr200) were unsuccessful. Taken together, these data suggest that SMIPPs have lost the ability to bind substrates in a classical "canonical" fashion, and instead have evolved alternative functions in the lifecycle of the scabies mite.
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Affiliation(s)
- Katja Fischer
- Scabies Laboratory, Queensland Institute of Medical Research, Brisbane, Australia.
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36
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Rosado CJ, Kondos S, Bull TE, Kuiper MJ, Law RHP, Buckle AM, Voskoboinik I, Bird PI, Trapani JA, Whisstock JC, Dunstone MA. The MACPF/CDC family of pore-forming toxins. Cell Microbiol 2008; 10:1765-74. [PMID: 18564372 PMCID: PMC2654483 DOI: 10.1111/j.1462-5822.2008.01191.x] [Citation(s) in RCA: 207] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Pore-forming toxins (PFTs) are commonly associated with bacterial pathogenesis. In eukaryotes, however, PFTs operate in the immune system or are deployed for attacking prey (e.g. venoms). This review focuses upon two families of globular protein PFTs: the cholesterol-dependent cytolysins (CDCs) and the membrane attack complex/perforin superfamily (MACPF). CDCs are produced by Gram-positive bacteria and lyse or permeabilize host cells or intracellular organelles during infection. In eukaryotes, MACPF proteins have both lytic and non-lytic roles and function in immunity, invasion and development. The structure and molecular mechanism of several CDCs are relatively well characterized. Pore formation involves oligomerization and assembly of soluble monomers into a ring-shaped pre-pore which undergoes conformational change to insert into membranes, forming a large amphipathic transmembrane β-barrel. In contrast, the structure and mechanism of MACPF proteins has remained obscure. Recent crystallographic studies now reveal that although MACPF and CDCs are extremely divergent at the sequence level, they share a common fold. Together with biochemical studies, these structural data suggest that lytic MACPF proteins use a CDC-like mechanism of membrane disruption, and will help understand the roles these proteins play in immunity and development.
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Affiliation(s)
- Carlos J Rosado
- Department of Biochemistry, Monash University, Clayton, Victoria 3800, Australia
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37
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Fenalti G, Hampe CS, Arafat Y, Law RHP, Banga JP, Mackay IR, Whisstock JC, Buckle AM, Rowley MJ. COOH-terminal clustering of autoantibody and T-cell determinants on the structure of GAD65 provide insights into the molecular basis of autoreactivity. Diabetes 2008; 57:1293-301. [PMID: 18184926 DOI: 10.2337/db07-1461] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE To gain structural insights into the autoantigenic properties of GAD65 in type 1 diabetes, we analyzed experimental epitope mapping data in the context of the recently determined crystal structures of GAD65 and GAD67, to allow "molecular positioning" of epitope sites for B- and T-cell reactivity. RESEARCH DESIGN AND METHODS Data were assembled from analysis of reported effects of mutagenesis of GAD65 on its reactivity with a panel of 11 human monoclonal antibodies (mAbs), supplemented by use of recombinant Fab to cross-inhibit reactivity with GAD65 by radioimmunoprecipitation of the same mAbs. RESULTS The COOH-terminal region on GAD65 was the major autoantigenic site. B-cell epitopes were distributed within two separate clusters around different faces of the COOH-terminal domain. Inclusion of epitope sites in the pyridoxal phosphate-and NH(2)-terminal domains was attributed to the juxtaposition of all three domains in the crystal structure. Epitope preferences of different mAbs to GAD65 aligned with different clinical expressions of type 1 diabetes. Epitopes for four of five known reactive T-cell sequences restricted by HLA DRB1*0401 were aligned to solvent-exposed regions of the GAD65 structure and colocalized within the two B-cell epitope clusters. The continuous COOH-terminal epitope region of GAD65 was structurally highly flexible and therefore differed markedly from the equivalent region of GAD67. CONCLUSIONS Structural features could explain the differing antigenicity, and perhaps immunogenicity, of GAD65 versus GAD67. The proximity of B- and T-cell epitopes within the GAD65 structure suggests that antigen-antibody complexes may influence antigen processing by accessory cells and thereby T-cell reactivity.
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Affiliation(s)
- Gustavo Fenalti
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
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Zhang Q, Law RHP, Bottomley SP, Whisstock JC, Buckle AM. A structural basis for loop C-sheet polymerization in serpins. J Mol Biol 2008; 376:1348-59. [PMID: 18234218 DOI: 10.1016/j.jmb.2007.12.050] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2007] [Revised: 12/17/2007] [Accepted: 12/20/2007] [Indexed: 10/22/2022]
Abstract
In this study, we report the X-ray crystal structure of an N-terminally truncated variant of the bacterial serpin, tengpin (tengpinDelta42). Our data reveal that tengpinDelta42 adopts a variation of the latent conformation in which the reactive center loop is hyperinserted into the A beta-sheet and removed from the vicinity of the C-sheet. This conformational change leaves the C beta-sheet completely exposed and permits antiparallel edge-strand interactions between the exposed portion of the reactive center loop of one molecule and strand s2C of the C beta-sheet of the neighboring molecule in the crystal lattice. Our structural data thus reveal that tengpinDelta42 forms a loop C-sheet polymer in the crystal lattice. In vivo serpins have a propensity to misfold and form long-chain polymers, a process that underlies serpinopathies such as emphysema, thrombosis and dementia. Native serpins are thought to polymerize via a loop A-sheet mechanism. However, studies on plasminogen activator inhibitor 1 and the S49P variant of human neuroserpin reveal that the latent form of these molecules can also polymerize. Polymerization of latent neuroserpin may be important for the development of familial encephalopathy with neuroserpin inclusion bodies. Our structural data provide a possible mechanism for polymerization by latent serpins.
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Affiliation(s)
- Qingwei Zhang
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, VIC 3800, Australia
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39
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Rosado CJ, Buckle AM, Law RHP, Butcher RE, Kan WT, Bird CH, Ung K, Browne KA, Baran K, Bashtannyk-Puhalovich TA, Faux NG, Wong W, Porter CJ, Pike RN, Ellisdon AM, Pearce MC, Bottomley SP, Emsley J, Smith AI, Rossjohn J, Hartland EL, Voskoboinik I, Trapani JA, Bird PI, Dunstone MA, Whisstock JC. A common fold mediates vertebrate defense and bacterial attack. Science 2007; 317:1548-51. [PMID: 17717151 DOI: 10.1126/science.1144706] [Citation(s) in RCA: 237] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Proteins containing membrane attack complex/perforin (MACPF) domains play important roles in vertebrate immunity, embryonic development, and neural-cell migration. In vertebrates, the ninth component of complement and perforin form oligomeric pores that lyse bacteria and kill virus-infected cells, respectively. However, the mechanism of MACPF function is unknown. We determined the crystal structure of a bacterial MACPF protein, Plu-MACPF from Photorhabdus luminescens, to 2.0 angstrom resolution. The MACPF domain reveals structural similarity with poreforming cholesterol-dependent cytolysins (CDCs) from Gram-positive bacteria. This suggests that lytic MACPF proteins may use a CDC-like mechanism to form pores and disrupt cell membranes. Sequence similarity between bacterial and vertebrate MACPF domains suggests that the fold of the CDCs, a family of proteins important for bacterial pathogenesis, is probably used by vertebrates for defense against infection.
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Affiliation(s)
- Carlos J Rosado
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
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40
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Zhang Q, Buckle AM, Law RHP, Pearce MC, Cabrita LD, Lloyd GJ, Irving JA, Smith AI, Ruzyla K, Rossjohn J, Bottomley SP, Whisstock JC. The N terminus of the serpin, tengpin, functions to trap the metastable native state. EMBO Rep 2007; 8:658-63. [PMID: 17557112 PMCID: PMC1905895 DOI: 10.1038/sj.embor.7400986] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2006] [Revised: 04/04/2007] [Accepted: 04/04/2007] [Indexed: 12/03/2022] Open
Abstract
Serpins fold to a metastable native state and are susceptible to undergoing spontaneous conformational change to more stable conformers, such as the latent form. We investigated conformational change in tengpin, an unusual prokaryotic serpin from the extremophile Thermoanaerobacter tengcongensis. In addition to the serpin domain, tengpin contains a functionally uncharacterized 56-amino-acid amino-terminal region. Deletion of this domain creates a variant—tengpinΔ51—which folds past the native state and readily adopts the latent conformation. Analysis of crystal structures together with mutagenesis studies show that the N terminus of tengpin protects a hydrophobic patch in the serpin domain and functions to trap tengpin in its native metastable state. A 13-amino-acid peptide derived from the N terminus is able to mimick the role of the N terminus in stabilizing the native state of tengpinΔ51. Therefore, the function of the N terminus in tengpin resembles protein cofactors that prevent mammalian serpins from spontaneously adopting the latent conformation.
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Affiliation(s)
- Qingwei Zhang
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - Ashley M Buckle
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - Ruby H P Law
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - Mary C Pearce
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - Lisa D Cabrita
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - Gordon J Lloyd
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - James A Irving
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - A Ian Smith
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria 3800, Australia
- ARC Centre of Excellence for Structural and Functional Microbial Genomics, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - Katya Ruzyla
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - Jamie Rossjohn
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria 3800, Australia
- ARC Centre of Excellence for Structural and Functional Microbial Genomics, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - Stephen P Bottomley
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria 3800, Australia
- Tel: +613 9905 3747; Fax: +613 9905 3703; E-mail:
| | - James C Whisstock
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, Victoria 3800, Australia
- ARC Centre of Excellence for Structural and Functional Microbial Genomics, Monash University, Clayton, Melbourne, Victoria 3800, Australia
- Tel: +613 9905 3747; Fax: +613 9905 4699; E-mail:
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Fenalti G, Law RHP, Buckle AM, Langendorf C, Tuck K, Rosado CJ, Faux NG, Mahmood K, Hampe CS, Banga JP, Wilce M, Schmidberger J, Rossjohn J, El-Kabbani O, Pike RN, Smith AI, Mackay IR, Rowley MJ, Whisstock JC. GABA production by glutamic acid decarboxylase is regulated by a dynamic catalytic loop. Nat Struct Mol Biol 2007; 14:280-6. [PMID: 17384644 DOI: 10.1038/nsmb1228] [Citation(s) in RCA: 159] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2006] [Accepted: 03/07/2007] [Indexed: 01/20/2023]
Abstract
Gamma-aminobutyric acid (GABA) is synthesized by two isoforms of the pyridoxal 5'-phosphate-dependent enzyme glutamic acid decarboxylase (GAD65 and GAD67). GAD67 is constitutively active and is responsible for basal GABA production. In contrast, GAD65, an autoantigen in type I diabetes, is transiently activated in response to the demand for extra GABA in neurotransmission, and cycles between an active holo form and an inactive apo form. We have determined the crystal structures of N-terminal truncations of both GAD isoforms. The structure of GAD67 shows a tethered loop covering the active site, providing a catalytic environment that sustains GABA production. In contrast, the same catalytic loop is inherently mobile in GAD65. Kinetic studies suggest that mobility in the catalytic loop promotes a side reaction that results in cofactor release and GAD65 autoinactivation. These data reveal the molecular basis for regulation of GABA homeostasis.
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Affiliation(s)
- Gustavo Fenalti
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Melbourne, VIC 3800, Australia
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42
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Hennebry SC, Law RHP, Richardson SJ, Buckle AM, Whisstock JC. The crystal structure of the transthyretin-like protein from Salmonella dublin, a prokaryote 5-hydroxyisourate hydrolase. J Mol Biol 2006; 359:1389-99. [PMID: 16787778 DOI: 10.1016/j.jmb.2006.04.057] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2006] [Revised: 04/21/2006] [Accepted: 04/22/2006] [Indexed: 10/24/2022]
Abstract
The mechanism of binding of thyroid hormones by the transport protein transthyretin (TTR) in vertebrates is structurally well characterised. However, a homologous family of transthyretin-like proteins (TLPs) present in bacteria as well as eukaryotes do not bind thyroid hormones, instead they are postulated to perform a role in the purine degradation pathway and function as 5-hydroxyisourate hydrolases. Here we describe the 2.5 Angstroms X-ray crystal structure of the TLP from the Gram-negative bacterium Salmonella dublin, and compare and contrast its structure with vertebrate TTRs. The overall architecture of the homotetramer is conserved and, despite low sequence homology with vertebrate TTRs, structural differences within the monomer are restricted to flexible loop regions. However, sequence variation at the dimer-dimer interface has profound consequences for the ligand binding site and provides a structural rationalisation for the absence of thyroid hormone binding affinity in bacterial TLPs: the deep, negatively charged thyroxine-binding pocket that characterises vertebrate TTR contrasts with a shallow and elongated, positively charged cleft in S. dublin TLP. We have demonstrated that Sdu_TLP is a 5-hydroxyisourate hydrolase. Furthermore, using site-directed mutagenesis, we have identified three conserved residues located in this cleft that are critical to the enzyme activity. Together our data reveal that the active site of Sdu_TLP corresponds to the thyroxine binding site in TTRs.
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Affiliation(s)
- Sarah C Hennebry
- The Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC, Australia
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Amin AA, Faux NG, Fenalti G, Williams G, Bernadou A, Daglish B, Keefe K, Middleton S, Rae J, Tetis K, Law RHP, Fulton KF, Rossjohn J, Whisstock JC, Buckle AM. Managing and mining protein crystallization data. Proteins 2005; 62:4-7. [PMID: 16287081 DOI: 10.1002/prot.20776] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The crystallization of macromolecules remains a major bottleneck in structural biology. The routine screening of more than one thousand crystallization conditions and subsequent optimization by fine screening presents a challenge to conventional laboratory notebook keeping. In addition, the development of high-throughput robotic crystallization and imaging systems presents a pressing need for low-cost laboratory information management system (LIMS). Here we describe CLIMS2, a crystallization LIMS that features a simple, user-friendly graphical interface, allowing the storage, management, retrieval and mining of crystallization data. The CLIMS2 executable and documentation is freely available at http://clims.med.monash.edu.au.
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Affiliation(s)
- Abdullah A Amin
- Victorian Bioinformatics Consortium, Monash University, Clayton, Victoria, Australia
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Law RHP, Irving JA, Buckle AM, Ruzyla K, Buzza M, Bashtannyk-Puhalovich TA, Beddoe TC, Nguyen K, Worrall DM, Bottomley SP, Bird PI, Rossjohn J, Whisstock JC. The high resolution crystal structure of the human tumor suppressor maspin reveals a novel conformational switch in the G-helix. J Biol Chem 2005; 280:22356-64. [PMID: 15760906 DOI: 10.1074/jbc.m412043200] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Maspin is a serpin that acts as a tumor suppressor in a range of human cancers, including tumors of the breast and lung. Maspin is crucial for development, because homozygous loss of the gene is lethal; however, the precise physiological role of the molecule is unclear. To gain insight into the function of human maspin, we have determined its crystal structure in two similar, but non-isomorphous crystal forms, to 2.1- and 2.8-A resolution, respectively. The structure reveals that maspin adopts the native serpin fold in which the reactive center loop is expelled fully from the A beta-sheet, makes minimal contacts with the core of the molecule, and exhibits a high degree of flexibility. A buried salt bridge unique to maspin orthologues causes an unusual bulge in the region around the D and E alpha-helices, an area of the molecule demonstrated in other serpins to be important for cofactor recognition. Strikingly, the structural data reveal that maspin is able to undergo conformational change in and around the G alpha-helix, switching between an open and a closed form. This change dictates the electrostatic character of a putative cofactor binding surface and highlights this region as a likely determinant of maspin function. The high resolution crystal structure of maspin provides a detailed molecular framework to elucidate the mechanism of function of this important tumor suppressor.
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Affiliation(s)
- Ruby H P Law
- The Protein Crystallography Unit, Monash Centre for Synchrotron Science and The Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Faculty of Medicine, Monash University, Clayton, Victoria 3800, Australia
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Law RHP, Smooker PM, Irving JA, Piedrafita D, Ponting R, Kennedy NJ, Whisstock JC, Pike RN, Spithill TW. Cloning and expression of the major secreted cathepsin B-like protein from juvenile Fasciola hepatica and analysis of immunogenicity following liver fluke infection. Infect Immun 2004; 71:6921-32. [PMID: 14638781 PMCID: PMC308908 DOI: 10.1128/iai.71.12.6921-6932.2003] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The functions of the cathepsin B-like proteases in liver flukes are unknown and analysis has been hindered by a lack of protein for study, since the protein is produced in small amounts by juvenile flukes. To circumvent this, we isolated and characterized a cDNA encoding the major secreted cathepsin B from Fasciola hepatica. The predicted preproprotein is 339 amino acids in length, with the mature protease predicted to be 254 amino acids long, and shows significant similarity to parasite and mammalian cathepsin B. Only one of the two conserved histidine residues required for cathepsin B exopeptidase activity is predicted to be present. Recombinant preproprotein was produced in yeast, and it was shown that the recombinant proprotein can undergo a degree of self-processing in vitro to the mature form, which is active against gelatin and synthetic peptide substrates. The recombinant protein is antigenic in vaccinated rats, and antibodies to the protein are detected early after infection of rats and sheep with F. hepatica. The kinetics of the response to cathepsin B and cathepsin L after infection of sheep and rats confirm the temporal expression of these proteins during the life cycle of the parasite.
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Affiliation(s)
- Ruby H P Law
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
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Tong JC, Mackay IR, Chin J, Law RHP, Fayad K, Rowley MJ. Enzymatic characterization of a recombinant isoform hybrid of glutamic acid decarboxylase (rGAD67/65) expressed in yeast. J Biotechnol 2002; 97:183-90. [PMID: 12067524 DOI: 10.1016/s0168-1656(02)00060-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND AND AIMS Glutamic acid decarboxylase (GAD, EC 4.1.1.15) catalyses the conversion of glutamate to gamma-aminobutyric acid (GABA). The 65 kDa isoform, GAD65 is a potent autoantigen in type 1 diabetes, whereas GAD67 is not. A hybrid cDNA was created by fusing a human cDNA for amino acids 1-101 of GAD67 to a human cDNA for amino acids 96-585 of GAD65; the recombinant (r) protein was expressed in yeast and was shown to have equivalent immunoreactivity to mammalian brain GAD with diabetes sera. We here report on enzymatic and molecular properties of rGAD67/65. METHODS Studies were performed on enzymatic activity of rGAD67/65 by production of 3H-GABA from 3H-glutamate, enzyme kinetics, binding to the enzyme cofactor pyridoxal phosphate (PLP), stability according to differences in pH, temperature and duration of storage, and antigenic reactivity with various GAD-specific antisera. RESULTS The properties of rGAD67/65 were compared with published data for mammalian brain GAD (brackets). These included a specific enzyme activity of 22.7 (16.7) nKat, optimal pH for enzymatic activity 7.4 (6.8), K(m) of 1.3 (1.3) mM, efficient non-covalent binding to the cofactor PLP, and high autoantigenic potency. The stability of rGAD67/65 was optimal over 3 months at -80 degrees C, or in lyophilized form at -20 degrees C. CONCLUSIONS Hybrid rGAD67/65 has enzymatic and other properties similar to those of the mixed isoforms of GAD in preparations from mammalian brain as described elsewhere, in addition to its previously described similar immunoreactivity.
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Affiliation(s)
- Jonathan C Tong
- Department of Biochemistry and Molecular Biology, Monash University, Clayton Vic. 3800, Australia
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