1
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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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2
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Oskam N, den Boer MA, Lukassen MV, Ooijevaar-de Heer P, Veth TS, van Mierlo G, Lai SH, Derksen NIL, Yin V, Streutker M, Franc V, Šiborová M, Damen MJA, Kos D, Barendregt A, Bondt A, van Goudoever JB, de Haas CJC, Aerts PC, Muts RM, Rooijakkers SHM, Vidarsson G, Rispens T, Heck AJR. CD5L is a canonical component of circulatory IgM. Proc Natl Acad Sci U S A 2023; 120:e2311265120. [PMID: 38055740 PMCID: PMC10723121 DOI: 10.1073/pnas.2311265120] [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: 07/03/2023] [Accepted: 11/07/2023] [Indexed: 12/08/2023] Open
Abstract
Immunoglobulin M (IgM) is an evolutionary conserved key component of humoral immunity, and the first antibody isotype to emerge during an immune response. IgM is a large (1 MDa), multimeric protein, for which both hexameric and pentameric structures have been described, the latter additionally containing a joining (J) chain. Using a combination of single-particle mass spectrometry and mass photometry, proteomics, and immunochemical assays, we here demonstrate that circulatory (serum) IgM exclusively exists as a complex of J-chain-containing pentamers covalently bound to the small (36 kDa) protein CD5 antigen-like (CD5L, also called apoptosis inhibitor of macrophage). In sharp contrast, secretory IgM in saliva and milk is principally devoid of CD5L. Unlike IgM itself, CD5L is not produced by B cells, implying that it associates with IgM in the extracellular space. We demonstrate that CD5L integration has functional implications, i.e., it diminishes IgM binding to two of its receptors, the FcαµR and the polymeric Immunoglobulin receptor. On the other hand, binding to FcµR as well as complement activation via C1q seem unaffected by CD5L integration. Taken together, we redefine the composition of circulatory IgM as a J-chain containing pentamer, always in complex with CD5L.
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Affiliation(s)
- Nienke Oskam
- Sanquin Research and Landsteiner Laboratory, Department of Immunopathology, Amsterdam University Medical Center, Amsterdam1066 CX, the Netherlands
| | - Maurits A. den Boer
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht3584 CH, the Netherlands
- Netherlands Proteomics Center, Utrecht3584 CH, the Netherlands
| | - Marie V. Lukassen
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht3584 CH, the Netherlands
- Netherlands Proteomics Center, Utrecht3584 CH, the Netherlands
| | - Pleuni Ooijevaar-de Heer
- Sanquin Research and Landsteiner Laboratory, Department of Immunopathology, Amsterdam University Medical Center, Amsterdam1066 CX, the Netherlands
| | - Tim S. Veth
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht3584 CH, the Netherlands
- Netherlands Proteomics Center, Utrecht3584 CH, the Netherlands
| | - Gerard van Mierlo
- Sanquin Research and Landsteiner Laboratory, Department of Immunopathology, Amsterdam University Medical Center, Amsterdam1066 CX, the Netherlands
| | - Szu-Hsueh Lai
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht3584 CH, the Netherlands
- Netherlands Proteomics Center, Utrecht3584 CH, the Netherlands
| | - Ninotska I. L. Derksen
- Sanquin Research and Landsteiner Laboratory, Department of Immunopathology, Amsterdam University Medical Center, Amsterdam1066 CX, the Netherlands
| | - Victor Yin
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht3584 CH, the Netherlands
- Netherlands Proteomics Center, Utrecht3584 CH, the Netherlands
| | - Marij Streutker
- Sanquin Research and Landsteiner Laboratory, Department of Immunopathology, Amsterdam University Medical Center, Amsterdam1066 CX, the Netherlands
| | - Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht3584 CH, the Netherlands
- Netherlands Proteomics Center, Utrecht3584 CH, the Netherlands
| | - Marta Šiborová
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht3584 CH, the Netherlands
- Netherlands Proteomics Center, Utrecht3584 CH, the Netherlands
| | - Mirjam J. A. Damen
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht3584 CH, the Netherlands
- Netherlands Proteomics Center, Utrecht3584 CH, the Netherlands
| | - Dorien Kos
- Sanquin Research and Landsteiner Laboratory, Department of Immunopathology, Amsterdam University Medical Center, Amsterdam1066 CX, the Netherlands
| | - Arjan Barendregt
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht3584 CH, the Netherlands
- Netherlands Proteomics Center, Utrecht3584 CH, the Netherlands
| | - Albert Bondt
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht3584 CH, the Netherlands
- Netherlands Proteomics Center, Utrecht3584 CH, the Netherlands
| | - Johannes B. van Goudoever
- Amsterdam University Medical Center, Vrije Universiteit, University of Amsterdam, Emma Children's Hospital, Amsterdam1105 AZ, the Netherlands
| | - Carla J. C. de Haas
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht3584 CX, the Netherlands
| | - Piet C. Aerts
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht3584 CX, the Netherlands
| | - Remy M. Muts
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht3584 CX, the Netherlands
| | - Suzan H. M. Rooijakkers
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht3584 CX, the Netherlands
| | - Gestur Vidarsson
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht3584 CH, the Netherlands
- Netherlands Proteomics Center, Utrecht3584 CH, the Netherlands
- Sanquin Research and Landsteiner Laboratory, Department of Experimental Immunohematology, Amsterdam University Medical Center, Amsterdam1066 CX, the Netherlands
| | - Theo Rispens
- Sanquin Research and Landsteiner Laboratory, Department of Immunopathology, Amsterdam University Medical Center, Amsterdam1066 CX, the Netherlands
| | - Albert J. R. Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht3584 CH, the Netherlands
- Netherlands Proteomics Center, Utrecht3584 CH, the Netherlands
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3
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Cramer DAT, Franc V, Heidenreich AK, Hook M, Adibzadeh M, Reusch D, Heck AJR, Haberger M. Characterization of high-molecular weight by-products in the production of a trivalent bispecific 2+1 heterodimeric antibody. MAbs 2023; 15:2175312. [PMID: 36799476 PMCID: PMC9980510 DOI: 10.1080/19420862.2023.2175312] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
The development of increasingly complex antibody formats, such as bispecifics, can lead to the formation of increasingly complex high- and low-molecular-weight by-products. Here, we focus on the characterization of high molecular weight species (HMWs) representing the highest complexity of size variants. Standard methods used for product release, such as size exclusion chromatography (SEC), can separate HMW by-products from the main product, but cannot distinguish smaller changes in mass. Here, for the identification of the diverse and complex HMW variants of a trivalent bispecific CrossMAb antibody, offline fractionation, as well as production of HMW by-products combined with comprehensive analytical testing, was applied. Furthermore, HMW variants were analyzed regarding their chemical binding nature and tested in functional assays regarding changes in potency of the variants. Changes in potency were explained by detailed characterization using mass photometry, SDS-PAGE analysis, native mass spectrometry (MS) coupled to SEC and bottom-up proteomics. We identified a major portion of the HMW by-products to be non-covalently linked, leading to dissociation and changes in activity. We also identified and localized high heterogeneity of a by-product of concern and applied a CD3 affinity column coupled to native MS to annotate unexpected by-products. We present here a multi-method approach for the characterization of complex HMW by-products. A better understanding of these by-products is beneficial to guide analytical method development and proper specification setting for therapeutic bispecific antibodies to ensure constant efficacy and patient safety of the product through the assessment of by-products.
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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 Sciences, University of Utrecht, Utrecht, The Netherlands.,Netherlands Proteomics Center, Utrecht, The Netherlands
| | - Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, The Netherlands.,Netherlands Proteomics Center, Utrecht, The Netherlands
| | | | - Michaela Hook
- Pharma Technical Development, Roche Diagnostics GmbH, Penzberg, Germany
| | - Mahdi Adibzadeh
- Pharma Technical Development, F. Hoffmann-La Roche AG, Basel, Switzerland
| | - Dietmar Reusch
- Pharma Technical Development, Roche Diagnostics GmbH, Penzberg, Germany
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, The Netherlands.,Netherlands Proteomics Center, Utrecht, The Netherlands
| | - Markus Haberger
- Pharma Technical Development, Roche Diagnostics GmbH, Penzberg, Germany
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4
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Cramer DAT, Franc V, Caval T, Heck AJR. Charting the Proteoform Landscape of Serum Proteins in Individual Donors by High-Resolution Native Mass Spectrometry. Anal Chem 2022; 94:12732-12741. [PMID: 36074704 PMCID: PMC9494300 DOI: 10.1021/acs.analchem.2c02215] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [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: 11/28/2022]
Abstract
![]()
Most proteins in serum are glycosylated, with several
annotated
as biomarkers and thus diagnostically important and of interest for
their role in disease. Most methods for analyzing serum glycoproteins
employ either glycan release or glycopeptide centric mass spectrometry-based
approaches, which provide excellent tools for analyzing known glycans
but neglect previously undefined or unknown glycosylation and/or other
co-occurring modifications. High-resolution native mass spectrometry
is a relatively new technique for the analysis of intact glycoproteins,
providing a “what you see is what you get” mass profile
of a protein, allowing the qualitative and quantitative observation
of all modifications present. So far, a disadvantage of this approach
has been that it centers mostly on just one specific serum glycoprotein
at the time. To address this issue, we introduce an ion-exchange chromatography-based
fractionation method capable of isolating and analyzing, in parallel,
over 20 serum (glyco)proteins, covering a mass range between 30 and
190 kDa, from 150 μL of serum. Although generating data in parallel
for all these 20 proteins, we focus the discussion on the very complex
proteoform profiles of four selected proteins, i.e., α-1-antitrypsin,
ceruloplasmin, hemopexin, and complement protein C3. Our analyses
provide an insight into the extensive proteoform landscape of serum
proteins in individual donors, caused by the occurrence of various N- and O-glycans, protein cysteinylation,
and co-occurring genetic variants. Moreover, native mass intact mass
profiling also provided an edge over alternative approaches revealing
the presence of apo- and holo-forms of ceruloplasmin and the endogenous
proteolytic processing in plasma of among others complement protein
C3. We also applied our approach to a small cohort of serum samples
from healthy and diseased individuals. In these, we qualitatively
and quantitatively monitored the changes in proteoform profiles of
ceruloplasmin and revealed a substantial increase in fucosylation
and glycan occupancy in patients with late-stage hepatocellular carcinoma
and pancreatic cancer as compared to healthy donor samples.
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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, Padualaan 8, Utrecht 3584 CH, The Netherlands.,Netherlands Proteomics Centre, University of Utrecht, Padualaan 8, Utrecht 3584 CH, The Netherlands
| | - Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Science, University of Utrecht, Padualaan 8, Utrecht 3584 CH, The Netherlands.,Netherlands Proteomics Centre, University of Utrecht, Padualaan 8, Utrecht 3584 CH, The Netherlands
| | - Tomislav Caval
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Science, University of Utrecht, Padualaan 8, Utrecht 3584 CH, The Netherlands.,Netherlands Proteomics Centre, University of Utrecht, Padualaan 8, Utrecht 3584 CH, The Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Science, University of Utrecht, Padualaan 8, Utrecht 3584 CH, The Netherlands.,Netherlands Proteomics Centre, University of Utrecht, Padualaan 8, Utrecht 3584 CH, The Netherlands
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5
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Doorduijn DJ, Lukassen MV, van 't Wout MFL, Franc V, Ruyken M, Bardoel BW, Heck AJR, Rooijakkers SHM. Soluble MAC is primarily released from MAC-resistant bacteria that potently convert complement component C5. eLife 2022; 11:77503. [PMID: 35947526 PMCID: PMC9402229 DOI: 10.7554/elife.77503] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 08/01/2022] [Indexed: 11/21/2022] Open
Abstract
The membrane attack complex (MAC or C5b-9) is an important effector of the immune system to kill invading microbes. MAC formation is initiated when complement enzymes on the bacterial surface convert complement component C5 into C5b. Although the MAC is a membrane-inserted complex, soluble forms of MAC (sMAC), or terminal complement complex (TCC), are often detected in sera of patients suffering from infections. Consequently, sMAC has been proposed as a biomarker, but it remains unclear when and how it is formed during infections. Here, we studied mechanisms of MAC formation on different Gram-negative and Gram-positive bacteria and found that sMAC is primarily formed in human serum by bacteria resistant to MAC-dependent killing. Surprisingly, C5 was converted into C5b more potently by MAC-resistant compared to MAC-sensitive Escherichia coli strains. In addition, we found that MAC precursors are released from the surface of MAC-resistant bacteria during MAC assembly. Although release of MAC precursors from bacteria induced lysis of bystander human erythrocytes, serum regulators vitronectin (Vn) and clusterin (Clu) can prevent this. Combining size exclusion chromatography with mass spectrometry profiling, we show that sMAC released from bacteria in serum is a heterogeneous mixture of complexes composed of C5b-8, up to three copies of C9 and multiple copies of Vn and Clu. Altogether, our data provide molecular insight into how sMAC is generated during bacterial infections. This fundamental knowledge could form the basis for exploring the use of sMAC as biomarker.
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Affiliation(s)
- Dennis J Doorduijn
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Marie V Lukassen
- Biomolecular Mass Spectrometry and Proteomics, Utrecht University, Utrecht, Netherlands
| | - Marije F L van 't Wout
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Utrecht University, Utrecht, Netherlands
| | - Maartje Ruyken
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Bart W Bardoel
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Utrecht University, Utrecht, Netherlands
| | - Suzan H M Rooijakkers
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, Netherlands
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6
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Gazi I, Franc V, Tamara S, van Gool MP, Huppertz T, Heck AJ. Identifying glycation hot-spots in bovine milk proteins during production and storage of skim milk powder. Int Dairy J 2022. [DOI: 10.1016/j.idairyj.2022.105340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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7
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van Schaick G, Domínguez-Vega E, Gstöttner C, van den Berg-Verleg JH, Schouten O, Akeroyd M, Olsthoorn MMA, Wuhrer M, Heck AJR, Abello N, Franc V. Native Structural and Functional Proteoform Characterization of the Prolyl-Alanyl-Specific Endoprotease EndoPro from Aspergillus niger. J Proteome Res 2021; 20:4875-4885. [PMID: 34515489 PMCID: PMC8491274 DOI: 10.1021/acs.jproteome.1c00663] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
The prolyl-alanyl-specific
endoprotease (EndoPro) is an industrial
enzyme produced in Aspergillus niger. EndoPro is
mainly used for food applications but also as a protease in proteomics.
In-depth characterization of this enzyme is essential to understand
its structural features and functionality. However, there is a lack
of analytical methods capable of maintaining both the structural and
functional integrity of separated proteoforms. In this study, we developed
an anion exchange (AEX) method coupled to native mass spectrometry
(MS) for profiling EndoPro proteoforms. Moreover, we investigated
purified EndoPro proteoforms with complementary MS-based approaches,
including released N-glycan and glycopeptide analysis, to obtain a
comprehensive overview of the structural heterogeneity. We showed
that EndoPro has at least three sequence variants and seven N-glycosylation
sites occupied by high-mannose glycans that can be phosphorylated.
Each glycosylation site showed high microheterogeneity with ∼20
glycans per site. The functional characterization of fractionated
proteoforms revealed that EndoPro proteoforms remained active after
AEX-separation and the specificity of these proteoforms did not depend
on N-glycan phosphorylation. Nevertheless, our data confirmed a strong
pH dependence of EndoPro cleavage activity. Altogether, our study
demonstrates that AEX-MS is an excellent tool to characterize complex
industrial enzymes under native conditions.
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Affiliation(s)
- Guusje van Schaick
- Leiden University Medical Center, Center for Proteomics and Metabolomics, Albinusdreef 2, 2333 ZA, Leiden, The Netherlands
| | - Elena Domínguez-Vega
- Leiden University Medical Center, Center for Proteomics and Metabolomics, Albinusdreef 2, 2333 ZA, Leiden, The Netherlands
| | - Christoph Gstöttner
- Leiden University Medical Center, Center for Proteomics and Metabolomics, Albinusdreef 2, 2333 ZA, Leiden, The Netherlands
| | | | - Olaf Schouten
- DSM Biotechnology Center, Center for Enabling Innovation, Alexander Fleminglaan 1, 2613 AX, Delft, The Netherlands
| | - Michiel Akeroyd
- DSM Biotechnology Center, Center for Enabling Innovation, Alexander Fleminglaan 1, 2613 AX, Delft, The Netherlands
| | - Maurien M A Olsthoorn
- DSM Biotechnology Center, Center for Enabling Innovation, Alexander Fleminglaan 1, 2613 AX, Delft, The Netherlands
| | - Manfred Wuhrer
- Leiden University Medical Center, Center for Proteomics and Metabolomics, Albinusdreef 2, 2333 ZA, Leiden, The Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, 3584 CH, Utrecht, The Netherlands.,Netherlands Proteomics Center, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Nicolas Abello
- DSM Biotechnology Center, Center for Enabling Innovation, Alexander Fleminglaan 1, 2613 AX, Delft, The Netherlands
| | - Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, 3584 CH, Utrecht, The Netherlands.,Netherlands Proteomics Center, Padualaan 8, 3584 CH, Utrecht, The Netherlands
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8
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Lukassen MV, Franc V, Hevler JF, Heck AJR. Similarities and differences in the structures and proteoform profiles of the complement proteins C6 and C7. Proteomics 2021; 21:e2000310. [PMID: 34241972 DOI: 10.1002/pmic.202000310] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 06/24/2021] [Accepted: 07/05/2021] [Indexed: 11/08/2022]
Abstract
The human complement system provides a first line of defence against pathogens. It requires a well-orchestrated sequential assembly of an array of terminal complement components (C5, C6, C7, C8, and C9), ultimately forming the membrane attack complex (MAC). Although much information about MAC assembly is available, the structure of the soluble C7 has remained elusive. The complement proteins C7 and C6 share very high sequence homology and exhibit several conserved domains, disulphide bridges, and C-mannosylation sites. Here, we used an integrative structural MS-based approach combining native MS, glycopeptide-centric MS, in-gel cross-linking MS (IGX-MS) and structural modelling to describe structural features, including glycosylation, of human serum soluble C7. We compare this data with structural and glycosylation data for human serum C6. The new structural model for C7 shows that it adopts a compact conformation in solution. Although C6 and C7 share many similarities, our data reveals distinct O-, and N-linked glycosylation patterns in terms of location and glycan composition. Cumulatively, our data provide valuable new insight into the structure and proteoforms of C7, solving an essential piece of the puzzle in our understanding of MAC assembly.
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Affiliation(s)
- Marie V Lukassen
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, The Netherlands.,Netherlands Proteomics Center, The Netherlands
| | - Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, The Netherlands.,Netherlands Proteomics Center, The Netherlands
| | - Johannes F Hevler
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, The Netherlands.,Netherlands Proteomics Center, The Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, The Netherlands.,Netherlands Proteomics Center, The Netherlands
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9
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Abstract
Gene therapy approaches now allow for the production of therapeutic antibodies by healthy or cancerous human tissues directly in vivo, and, with an increasing number of gene delivery methods available, the cell type for expression can be chosen. Yet, little is known about the biophysical changes introduced by expressing antibodies from producer cells or tissues targeted by gene therapy approaches, nor about the consequences for the type of glycosylation. The effects of different glycosylation on therapeutic antibodies have been well studied by controlling their glycan compositions in non-human mammalian production cells, i.e., Chinese hamster ovary cells. Therefore, we investigated the glycosylation state of clinically approved antibodies secreted from cancer tissues frequently targeted by in vivo gene therapy, using native mass spectrometry and glycoproteomics. We found that antibody sialylation and fucosylation depended on the producer tissue and the antibody isotype, allowing us to identify optimal producer cell types according to the desired mode of action of the antibody. Furthermore, we discovered that high amounts (>20%) of non-glycosylated antibodies were produced in cells sensitive to the action of the produced antibodies. Different glycosylation in different producer cells can translate into an altered potency of in-vivo produced antibodies, depending on the desired mode of action, and can affect their serum half-lives. These results increase our knowledge about antibodies produced from cells targeted by gene therapy, enabling development of improved cancer gene therapy vectors that can include in vivo glycoengineering of expressed antibodies to optimize their efficacies, depending on the desired mode of action.
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Affiliation(s)
- Dominik Brücher
- Department of Biochemistry, University of Zurich , Zurich, Switzerland
| | - Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht , Utrecht, The Netherlands.,Netherlands Proteomics Center , Utrecht, The Netherlands
| | - Sheena N Smith
- Department of Biochemistry, University of Zurich , Zurich, Switzerland
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht , Utrecht, The Netherlands.,Netherlands Proteomics Center , Utrecht, The Netherlands
| | - Andreas Plückthun
- Department of Biochemistry, University of Zurich , Zurich, Switzerland
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10
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Hevler JF, Lukassen MV, Cabrera-Orefice A, Arnold S, Pronker MF, Franc V, Heck AJR. Selective cross-linking of coinciding protein assemblies by in-gel cross-linking mass spectrometry. EMBO J 2021; 40:e106174. [PMID: 33459420 PMCID: PMC7883291 DOI: 10.15252/embj.2020106174] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 12/03/2020] [Accepted: 12/10/2020] [Indexed: 12/18/2022] Open
Abstract
Cross-linking mass spectrometry has developed into an important method to study protein structures and interactions. The in-solution cross-linking workflows involve time and sample consuming steps and do not provide sensible solutions for differentiating cross-links obtained from co-occurring protein oligomers, complexes, or conformers. Here we developed a cross-linking workflow combining blue native PAGE with in-gel cross-linking mass spectrometry (IGX-MS). This workflow circumvents steps, such as buffer exchange and cross-linker concentration optimization. Additionally, IGX-MS enables the parallel analysis of co-occurring protein complexes using only small amounts of sample. Another benefit of IGX-MS, demonstrated by experiments on GroEL and purified bovine heart mitochondria, is the substantial reduction of undesired over-length cross-links compared to in-solution cross-linking. We next used IGX-MS to investigate the complement components C5, C6, and their hetero-dimeric C5b6 complex. The obtained cross-links were used to generate a refined structural model of the complement component C6, resembling C6 in its inactivated state. This finding shows that IGX-MS can provide new insights into the initial stages of the terminal complement pathway.
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Affiliation(s)
- Johannes F Hevler
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, The Netherlands.,Netherlands Proteomics Center, Utrecht, The Netherlands
| | - Marie V Lukassen
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, The Netherlands.,Netherlands Proteomics Center, Utrecht, The Netherlands
| | - Alfredo Cabrera-Orefice
- Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Susanne Arnold
- Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Matti F Pronker
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, The Netherlands.,Netherlands Proteomics Center, Utrecht, The Netherlands
| | - Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, The Netherlands.,Netherlands Proteomics Center, Utrecht, The Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, The Netherlands.,Netherlands Proteomics Center, Utrecht, The Netherlands
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11
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Čaval T, Lin YH, Varkila M, Reiding KR, Bonten MJM, Cremer OL, Franc V, Heck AJR. Glycoproteoform Profiles of Individual Patients' Plasma Alpha-1-Antichymotrypsin are Unique and Extensively Remodeled Following a Septic Episode. Front Immunol 2021; 11:608466. [PMID: 33519818 PMCID: PMC7840657 DOI: 10.3389/fimmu.2020.608466] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Accepted: 11/24/2020] [Indexed: 01/08/2023] Open
Abstract
Sepsis and septic shock remain the leading causes of death in intensive care units (ICUs), yet the pathogenesis originating from the inflammatory response during sepsis remains ambiguous. Acute-phase proteins are typically highly glycosylated, and the nature of the glycans have been linked to the incidence and severity of such inflammatory responses. To further build upon these findings we here monitored, the longitudinal changes in the plasma proteome and, in molecular detail, glycoproteoform profiles of alpha-1-antichymotrypsin (AACT) extracted from plasma of ten individual septic patients. For each patient we included four different time-points, including post-operative (before sepsis) and following discharge from the ICU. We isolated AACT from plasma depleted for albumin, IgG and serotransferrin and used high-resolution native mass spectrometry to qualitatively and quantitatively monitor the multifaceted glycan microheterogeneity of desialylated AACT, which allowed us to monitor how changes in the glycoproteoform profiles reflected the patient's physiological state. Although we observed a general trend in the remodeling of the AACT glycoproteoform profiles, e.g. increased fucosylation and branching/LacNAc elongation, each patient exhibited unique features and responses, providing a resilient proof-of-concept for the importance of personalized longitudinal glycoproteoform profiling. Importantly, we observed that the AACT glycoproteoform changes induced by sepsis did not readily subside after discharge from ICU.
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Affiliation(s)
- Tomislav Čaval
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, Netherlands
- Netherlands Proteomics Center, Utrecht, Netherlands
| | - Yu-Hsien Lin
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, Netherlands
- Netherlands Proteomics Center, Utrecht, Netherlands
| | - Meri Varkila
- Department of Intensive Care Medicine, University Medical Center Utrecht, Utrecht, Netherlands
| | - Karli R. Reiding
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, Netherlands
- Netherlands Proteomics Center, Utrecht, Netherlands
| | - Marc J. M. Bonten
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, Netherlands
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Olaf L. Cremer
- Department of Intensive Care Medicine, University Medical Center Utrecht, Utrecht, Netherlands
| | - Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, Netherlands
- Netherlands Proteomics Center, Utrecht, Netherlands
| | - Albert J. R. Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, Netherlands
- Netherlands Proteomics Center, Utrecht, Netherlands
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12
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Reiding KR, Franc V, Huitema MG, Brouwer E, Heeringa P, Heck AJR. Neutrophil myeloperoxidase harbors distinct site-specific peculiarities in its glycosylation. J Biol Chem 2019; 294:20233-20245. [PMID: 31719144 PMCID: PMC6937560 DOI: 10.1074/jbc.ra119.011098] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 11/08/2019] [Indexed: 12/22/2022] Open
Abstract
Anti-neutrophil cytoplasmic autoantibodies (ANCAs) are directed against lysosomal components of neutrophils. ANCAs directed to proteinase 3 and myeloperoxidase (MPO) in particular are associated with distinct forms of small vessel vasculitides. MPO is an abundant neutrophil-derived heme protein that is part of the antimicrobial defense system. The protein is typically present in the azurophilic granules of neutrophils, but a large portion may also enter the extracellular space. It remains unclear why MPO is frequently the target of antibody-mediated autoimmune responses. MPO is a homodimeric glycoprotein, posttranslationally modified with complex sugars at specific sites. Glycosylation can strongly influence protein function, affecting its folding, receptor interaction, and backbone accessibility. MPO potentially can be heavily modified as it harbors 5 putative N-glycosylation sites (10 in the mature dimer). Although considered important for MPO structure and function, the full scope and relative abundance of the glycans attached to MPO is unknown. Here, combining bottom-up glycoproteomics and native MS approaches, we structurally characterized MPO from neutrophils of healthy human donors. We quantified the relative occupancy levels of the glycans at each of the five sites and observed complex heterogeneity and site-specific glycosylation. In particular, we detected glycosylation phenotypes uncommon for glycoproteins in the extracellular space, such as a high abundance of phosphorylated high-mannose species and severely truncated small glycans having the size of paucimannose or smaller. We hypothesize that the atypical glycosylation pattern found on MPO might contribute to its specific processing and presentation as a self-antigen by antigen-presenting cells.
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Affiliation(s)
- Karli R Reiding
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, 3584 CH Utrecht, The Netherlands .,Netherlands Proteomics Center, 3584 CH Utrecht, The Netherlands
| | - Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, 3584 CH Utrecht, The Netherlands.,Netherlands Proteomics Center, 3584 CH Utrecht, The Netherlands
| | - Minke G Huitema
- Department of Rheumatology and Clinical Immunology, University Medical Center Groningen, University of Groningen, 9700 AB Groningen, The Netherlands
| | - Elisabeth Brouwer
- Department of Rheumatology and Clinical Immunology, University Medical Center Groningen, University of Groningen, 9700 AB Groningen, The Netherlands
| | - Peter Heeringa
- Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, 9700 AB Groningen, The Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, 3584 CH Utrecht, The Netherlands.,Netherlands Proteomics Center, 3584 CH Utrecht, The Netherlands
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13
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Lin YH, Zhu J, Meijer S, Franc V, Heck AJR. Glycoproteogenomics: A Frequent Gene Polymorphism Affects the Glycosylation Pattern of the Human Serum Fetuin/α-2-HS-Glycoprotein. Mol Cell Proteomics 2019; 18:1479-1490. [PMID: 31097672 PMCID: PMC6683009 DOI: 10.1074/mcp.ra119.001411] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 05/13/2019] [Indexed: 12/15/2022] Open
Abstract
Fetuin, also known as α-2-HS-glycoprotein (gene name: AHSG), is one of the more abundant glycoproteins secreted into the bloodstream. There are two frequently occurring alleles of human AHSG, resulting in three genotypes (AHSG*1, AHSG*2, and heterozygous AHSG1/2). The backbone amino acid sequences of fetuin coded by the AHSG*1 and AHSG*2 genes differ in two amino acids including one known O-glycosylation site (aa position 256). Although fetuin levels have been extensively studied, the originating genotype is often ignored in such analysis. As fetuin has been suggested repeatedly as a potential biomarker for several disorders, the question whether the gene polymorphism affects the fetuin profile is of great interest. In this work, we describe detailed proteoform profiles of fetuin, isolated from serum of 10 healthy and 10 septic patient individuals and investigate potential glycoproteogenomics correlations, e.g. how gene polymorphisms affect glycosylation. We established an efficient method for fetuin purification from individuals' serum using ion-exchange chromatography. Subsequently, we performed hybrid mass spectrometric approaches integrating data from native mass spectra and peptide-centric MS analysis. Our data reveal a crucial effect of the gene polymorphism on the glycosylation pattern of fetuin. Moreover, we clearly observed increased fucosylation in the samples derived from the septic patients. Our serum proteoform analysis, targeted at one protein obtained from 20 individuals, exposes the wide variability in proteoform profiles, which should be taken into consideration when using fetuin as biomarker. Importantly, focusing on a single or few proteins, the quantitative proteoform profiles can provide, as shown here, already ample data to classify individuals by genotype and disease state.
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Affiliation(s)
- Yu-Hsien Lin
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands; §Netherlands Proteomics Center, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Jing Zhu
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands; §Netherlands Proteomics Center, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Sander Meijer
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands; ¶Department of Molecular and Cellular Hemostasis, Sanquin Research, Amsterdam 1066 CX, the Netherlands
| | - Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands; §Netherlands Proteomics Center, Padualaan 8, 3584 CH Utrecht, The Netherlands.
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands; §Netherlands Proteomics Center, Padualaan 8, 3584 CH Utrecht, The Netherlands.
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14
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Abstract
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Fetuin,
also known as alpha-2-Heremans Schmid glycoprotein (AHSG),
belongs to some of the most abundant glycoproteins secreted into the
bloodstream. In blood, fetuins exhibit functions as carriers of metals
and small molecules. Bovine fetuin, which harbors 3 N-glycosylation
sites and a suggested half dozen O-glycosylation sites, has been used
often as a model glycoprotein to test novel analytical workflows in
glycoproteomics. Here we characterize and compare fetuin in depth,
using protein from three different biological sources: human serum,
bovine serum, and recombinant human fetuin expressed in HEK-293 cells,
with the aim to elucidate similarities and differences between these
proteins and the post-translational modifications they harbor. Combining
data from high-resolution native mass spectrometry and glycopeptide
centric LC-MS analysis, we qualitatively and quantitatively gather
information on fetuin protein maturation, N-glycosylation, O-glycosylation,
and phosphorylation. We provide direct experimental evidence that
both the human serum and part of the recombinant proteins are processed
into two chains (A and B) connected by a single interchain disulfide
bridge, whereas bovine fetuin remains a single-chain protein. Although
two N-glycosylation sites, one O-glycosylation site, and a phosphorylation
site are conserved from bovine to human, the stoichiometry of the
modifications and the specific glycoforms they harbor are quite distinct.
Comparing serum and recombinant human fetuin, we observe that the
serum protein harbors a much simpler proteoform profile, indicating
that the recombinant protein is not ideally engineered to mimic human
serum fetuin. Comparing the proteoform profile and post-translational
modifications of human and bovine serum fetuin, we observe that, although
the gene structures of these two proteins are alike, they represent
quite distinct proteins when their glycoproteoform profile is also
taken into consideration.
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Affiliation(s)
- Yu-Hsien Lin
- Biomolecular Mass Spectrometry and Proteomics , Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht , Padualaan 8 , 3584 CH Utrecht , The Netherlands.,Netherlands Proteomics Center , Padualaan 8 , 3584 CH Utrecht , The Netherlands
| | - Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics , Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht , Padualaan 8 , 3584 CH Utrecht , The Netherlands.,Netherlands Proteomics Center , Padualaan 8 , 3584 CH Utrecht , The Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics , Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht , Padualaan 8 , 3584 CH Utrecht , The Netherlands.,Netherlands Proteomics Center , Padualaan 8 , 3584 CH Utrecht , The Netherlands
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15
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van de Waterbeemd M, Tamara S, Fort KL, Damoc E, Franc V, Bieri P, Itten M, Makarov A, Ban N, Heck AJR. Dissecting ribosomal particles throughout the kingdoms of life using advanced hybrid mass spectrometry methods. Nat Commun 2018; 9:2493. [PMID: 29950687 PMCID: PMC6021402 DOI: 10.1038/s41467-018-04853-x] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 05/28/2018] [Indexed: 11/08/2022] Open
Abstract
Biomolecular mass spectrometry has matured strongly over the past decades and has now reached a stage where it can provide deep insights into the structure and composition of large cellular assemblies. Here, we describe a three-tiered hybrid mass spectrometry approach that enables the dissection of macromolecular complexes in order to complement structural studies. To demonstrate the capabilities of the approach, we investigate ribosomes, large ribonucleoprotein particles consisting of a multitude of protein and RNA subunits. We identify sites of sequence processing, protein post-translational modifications, and the assembly and stoichiometry of individual ribosomal proteins in four distinct ribosomal particles of bacterial, plant and human origin. Amongst others, we report extensive cysteine methylation in the zinc finger domain of the human S27 protein, the heptameric stoichiometry of the chloroplastic stalk complex, the heterogeneous composition of human 40S ribosomal subunits and their association to the CrPV, and HCV internal ribosome entry site RNAs.
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Affiliation(s)
- Michiel van de Waterbeemd
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, 3584CH, The Netherlands
- Netherlands Proteomics Center, 3584CH, Utrecht, The Netherlands
| | - Sem Tamara
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, 3584CH, The Netherlands
- Netherlands Proteomics Center, 3584CH, Utrecht, The Netherlands
| | - Kyle L Fort
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, 3584CH, The Netherlands
- Netherlands Proteomics Center, 3584CH, Utrecht, The Netherlands
- Thermo Fisher Scientific, 28199, Bremen, Germany
| | - Eugen Damoc
- Thermo Fisher Scientific, 28199, Bremen, Germany
| | - Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, 3584CH, The Netherlands
- Netherlands Proteomics Center, 3584CH, Utrecht, The Netherlands
| | - Philipp Bieri
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, 8093, Zurich, Switzerland
| | - Martin Itten
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, 8093, Zurich, Switzerland
| | - Alexander Makarov
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, 3584CH, The Netherlands
- Thermo Fisher Scientific, 28199, Bremen, Germany
| | - Nenad Ban
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, 8093, Zurich, Switzerland
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, 3584CH, The Netherlands.
- Netherlands Proteomics Center, 3584CH, Utrecht, The Netherlands.
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16
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Franc V, Zhu J, Heck AJR. Comprehensive Proteoform Characterization of Plasma Complement Component C8αβγ by Hybrid Mass Spectrometry Approaches. J Am Soc Mass Spectrom 2018; 29:1099-1110. [PMID: 29532326 PMCID: PMC6003997 DOI: 10.1007/s13361-018-1901-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 01/12/2018] [Accepted: 01/13/2018] [Indexed: 09/27/2023]
Abstract
The human complement hetero-trimeric C8αβγ (C8) protein assembly (~ 150 kDa) is an important component of the membrane attack complex (MAC). C8 initiates membrane penetration and coordinates MAC pore formation. Here, we charted in detail the structural micro-heterogeneity within C8, purified from human plasma, combining high-resolution native mass spectrometry and (glyco)peptide-centric proteomics. The intact C8 proteoform profile revealed at least ~ 20 co-occurring MS signals. Additionally, we employed ion exchange chromatography to separate purified C8 into four distinct fractions. Their native MS analysis revealed even more detailed structural micro-heterogeneity on C8. Subsequent peptide-centric analysis, by proteolytic digestion of C8 and LC-MS/MS, provided site-specific quantitative profiles of different types of C8 glycosylation. Combining all this data provides a detailed specification of co-occurring C8 proteoforms, including experimental evidence on N-glycosylation, C-mannosylation, and O-glycosylation. In addition to the known N-glycosylation sites, two more N-glycosylation sites were detected on C8. Additionally, we elucidated the stoichiometry of all C-mannosylation sites in all the thrombospondin-like (TSP) domains of C8α and C8β. Lastly, our data contain the first experimental evidence of O-linked glycans located on C8γ. Albeit low abundant, these O-glycans are the first PTMs ever detected on this subunit. By placing the observed PTMs in structural models of free C8 and C8 embedded in the MAC, it may be speculated that some of the newly identified modifications may play a role in the MAC formation. Graphical Abstract ᅟ.
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Affiliation(s)
- Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, 3584 CH, Utrecht, The Netherlands
- Netherlands Proteomics Center, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Jing Zhu
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, 3584 CH, Utrecht, The Netherlands
- Netherlands Proteomics Center, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, 3584 CH, Utrecht, The Netherlands.
- Netherlands Proteomics Center, Padualaan 8, 3584 CH, Utrecht, The Netherlands.
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17
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Bern M, Caval T, Kil YJ, Tang W, Becker C, Carlson E, Kletter D, Sen KI, Galy N, Hagemans D, Franc V, Heck AJR. Parsimonious Charge Deconvolution for Native Mass Spectrometry. J Proteome Res 2018; 17:1216-1226. [PMID: 29376659 PMCID: PMC5838638 DOI: 10.1021/acs.jproteome.7b00839] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
![]()
Charge
deconvolution infers the mass from mass over charge (m/z) measurements in electrospray ionization
mass spectra. When applied over a wide input m/z or broad target mass range, charge-deconvolution algorithms
can produce artifacts, such as false masses at one-half or one-third
of the correct mass. Indeed, a maximum entropy term in the objective
function of MaxEnt, the most commonly used charge deconvolution algorithm,
favors a deconvolved spectrum with many peaks over one with fewer
peaks. Here we describe a new “parsimonious” charge
deconvolution algorithm that produces fewer artifacts. The algorithm
is especially well-suited to high-resolution native mass spectrometry
of intact glycoproteins and protein complexes. Deconvolution of native
mass spectra poses special challenges due to salt and small molecule
adducts, multimers, wide mass ranges, and fewer and lower charge states.
We demonstrate the performance of the new deconvolution algorithm
on a range of samples. On the heavily glycosylated plasma properdin
glycoprotein, the new algorithm could deconvolve monomer and dimer
simultaneously and, when focused on the m/z range of the monomer, gave accurate and interpretable
masses for glycoforms that had previously been analyzed manually using m/z peaks rather than deconvolved masses.
On therapeutic antibodies, the new algorithm facilitated the analysis
of extensions, truncations, and Fab glycosylation. The algorithm facilitates
the use of native mass spectrometry for the qualitative and quantitative
analysis of protein and protein assemblies.
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Affiliation(s)
- Marshall Bern
- Protein Metrics, Inc. , San Carlos, California 94070, United States
| | - Tomislav Caval
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Science4Life, Utrecht University and Netherlands Proteomics Centre , Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Yong J Kil
- Protein Metrics, Inc. , San Carlos, California 94070, United States
| | - Wilfred Tang
- Protein Metrics, Inc. , San Carlos, California 94070, United States
| | | | - Eric Carlson
- Protein Metrics, Inc. , San Carlos, California 94070, United States
| | - Doron Kletter
- Protein Metrics, Inc. , San Carlos, California 94070, United States
| | - K Ilker Sen
- Protein Metrics, Inc. , San Carlos, California 94070, United States
| | - Nicolas Galy
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Science4Life, Utrecht University and Netherlands Proteomics Centre , Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Dominique Hagemans
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Science4Life, Utrecht University and Netherlands Proteomics Centre , Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Science4Life, Utrecht University and Netherlands Proteomics Centre , Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Science4Life, Utrecht University and Netherlands Proteomics Centre , Padualaan 8, 3584 CH Utrecht, The Netherlands
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Franc V, Fikar O, Bartos K, Sofka M. Learning data discretization via convex optimization. Mach Learn 2017. [DOI: 10.1007/s10994-017-5654-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Yang Y, Franc V, Heck AJ. Glycoproteomics: A Balance between High-Throughput and In-Depth Analysis. Trends Biotechnol 2017; 35:598-609. [DOI: 10.1016/j.tibtech.2017.04.010] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 04/15/2017] [Accepted: 04/20/2017] [Indexed: 11/25/2022]
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Franc V, Yang Y, Heck AJR. Proteoform Profile Mapping of the Human Serum Complement Component C9 Revealing Unexpected New Features of N-, O-, and C-Glycosylation. Anal Chem 2017; 89:3483-3491. [PMID: 28221766 PMCID: PMC5362742 DOI: 10.1021/acs.analchem.6b04527] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [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: 12/28/2022]
Abstract
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The human complement
C9 protein (∼65 kDa) is a member of
the complement pathway. It plays an essential role in the membrane
attack complex (MAC), which forms a lethal pore on the cellular surface
of pathogenic bacteria. Here, we charted in detail the structural
microheterogeneity of C9 purified from human blood serum, using an
integrative workflow combining high-resolution native mass spectrometry
and (glyco)peptide-centric proteomics. The proteoform profile of C9
was acquired by high-resolution native mass spectrometry, which revealed
the co-occurrence of ∼50 distinct mass spectrometry (MS) signals.
Subsequent peptide-centric analysis, through proteolytic digestion
of C9 and liquid chromatography (LC)-tandem mass spectrometry (MS/MS)
measurements of the resulting peptide mixtures, provided site-specific
quantitative profiles of three different types of C9 glycosylation
and validation of the native MS data. Our study provides a detailed
specification, validation, and quantification of 15 co-occurring C9
proteoforms and the first direct experimental evidence of O-linked glycans in the N-terminal region.
Additionally, next to the two known glycosylation sites, a third novel,
albeit low abundant, N-glycosylation site on C9 is
identified, which surprisingly does not possess the canonical N-glycosylation sequence N-X-S/T. Our data also reveal a
binding of up to two Ca2+ ions to C9. Mapping all detected
and validated sites of modifications on a structural model of C9,
as present in the MAC, hints at their putative roles in pore formation
or receptor interactions. The applied methods herein represent a powerful
tool for the unbiased in-depth analysis of plasma proteins and may
advance biomarker discovery, as aberrant glycosylation profiles may
be indicative of the pathophysiological state of the patients.
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Affiliation(s)
- Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht , Padualaan 8, 3584 CH Utrecht, The Netherlands.,Netherlands Proteomics Center , Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Yang Yang
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht , Padualaan 8, 3584 CH Utrecht, The Netherlands.,Netherlands Proteomics Center , Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht , Padualaan 8, 3584 CH Utrecht, The Netherlands.,Netherlands Proteomics Center , Padualaan 8, 3584 CH Utrecht, The Netherlands
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Dycka F, Franc V, Frycak P, Raus M, Rehulka P, Lenobel R, Allmaier G, Marchetti-Deschmann M, Sebela M. Evaluation of Pseudotrypsin Cleavage Specificity Towards Proteins by MALDI-TOF Mass Spectrometry. Protein Pept Lett 2016; 22:1123-32. [PMID: 26446562 DOI: 10.2174/0929866522666151008151617] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 08/09/2015] [Accepted: 10/07/2015] [Indexed: 11/22/2022]
Abstract
Trypsin is a protease, which is commonly used for the digestion of protein samples in proteomic experiments. The process of trypsin autolysis is known to produce autolytic peptides as well as active enzyme forms with one or more intra-chain splits. In consequence, their variable presence can influence the digestion of a protein substrate in the reaction mixture. Besides two major and well-studied forms named β-trypsin and α-trypsin, there are also other active trypsin forms known such as γ-trypsin and pseudotrypsin (ψ-trypsin). In this work, the cleavage specificity of ψ-trypsin was evaluated using in-gel digestion of protein standards followed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) and tandem mass spectrometry (MS/MS) analyses of the resulting peptides. The numbers of produced and matching peptides were similar to those obtained using α-/β-trypsin. The same experience was obtained with a real complex protein sample from rat urine. In previous reports, ψ-trypsin was supposed to generate non-specific cleavages, which has now been reevaluated. Purified ψ-trypsin cleaved all analyzed proteins preferentially on the C-terminal side of Lys and Arg residues in accordance with the canonical tryptic cleavage. However, a minor nonspecific cleavage performance was also registered (particularly after Tyr and Phe), which was considerably higher than in the case of trypsin itself.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Marek Sebela
- Department of Protein Biochemistry and Proteomics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, PalacKy University, .
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Sebela M, Rehulka P, Kábrt J, Rehulková H, Ozdian T, Raus M, Franc V, Chmelík J. Identification of N-glycosylation in prolyl endoprotease from Aspergillus niger and evaluation of the enzyme for its possible application in proteomics. J Mass Spectrom 2009; 44:1587-1595. [PMID: 19757411 DOI: 10.1002/jms.1667] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
An acidic prolyl endoprotease from Aspergillus niger was isolated from the commercial product Brewers Clarex to evaluate its possible application in proteomics. The chromatographic purification yielded a single protein band in sodium dodecyl sulfate polyacrylamide gel electrophoresis providing an apparent molecular mass of 63 kDa and a broad peak (m/z 58,061) in linear matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS) indicating the glycoprotein nature of the enzyme. Indeed, a colorimetric assessment with phenol and sulfuric acid showed the presence of neutral sugars (9% of weight). The subsequent treatment with N-glycosidase F released a variety of high-mannose type N-glycans, which were successfully detected using MALDI-TOF MS. MALDI-TOF/TOF tandem MS analysis of glycopeptides from a tryptic digest of prolyl endoprotease unraveled the identity of the N-glycosylation site in the primary structure. The data obtained also show that the enzyme is present in its processed form, i.e. without putative signal and propeptide parts. Spectrophotometric measurements demonstrated optimal activity at pH 4.0-4.5 and also high thermostability for the cleavage at the C-terminal part of proline residues. In-solution digestion of standard proteins (12-200 kDa) allowed to evaluate the cleavage specificity. The enzyme acts upon proline and alanine residues, but there is an additional minor cleavage at some other residues like Gly, Leu, Arg, Ser and Tyr. The digestion of a honeybee peptide comprising six proline residues (apidaecin 1A) led to the detection of specific peptides terminated by proline as it was confirmed by MALDI postsource decay analysis.
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Affiliation(s)
- Marek Sebela
- Department of Biochemistry, Faculty of Science, Palacký University, Slechtitelů 11, CZ-783 71 Olomouc, Czech Republic.
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Franc V, Hrasko P, Snopko M. [Use of entomologic findings in forensic medicine and criminology]. Soud Lek 1989; 34:37-45. [PMID: 2799437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The submitted paper reacts to the unsatisfactory state as regards the literary treatment, and in particular the practical application of entomology in forensic medicine and criminology. The authors draw attention to the relatively wide perspectives of the application of entomological findings in the mentioned disciplines and define more accurately some terminological and oecological problems. The core of the work is a review of important species of necrophilous insects focused on Coleoptera. This part is introduced by an outline of oecological groups of necrophilous insects, whereby emphasis is given to their claims on habitat and food and their biotopical claims. The account of species is based on the chronological sequence as the insect invade the corpse in different stages of its destruction. Attention is paid also to abiotic (in particular climatic) factors which influence the rate of destruction. As to more extensive possible applications of entomology in the above disciplines, at least the following should be mentioned: 1. Application on the basis of the trophic relationship of insects and he corpses (time of death, possibly post-mortem transport based on investigation of the entomofauna of the corpse). 2. Information on restricted hygienic habits of the dead (the presence of ectoparasitic insects). 3. Passive intoxications, possibly active intoxications by poisonous insects. 4. Insects incidentally found on clothes, motor vehicles etc. during examination. In the conclusion the authors emphasize methodical problems of collection and processing of material and outline the prerequisites for extending and improving the application of entomological findings and methods in the mentioned disciplines.
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