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Hamey JJ, Nguyen A, Haddad M, Vázquez-Campos X, Pfeiffer PG, Wilkins MR. Methylation of elongation factor 1A by yeast Efm4 or human eEF1A-KMT2 involves a beta-hairpin recognition motif and crosstalks with phosphorylation. J Biol Chem 2024; 300:105639. [PMID: 38199565 PMCID: PMC10844748 DOI: 10.1016/j.jbc.2024.105639] [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: 07/24/2023] [Revised: 12/13/2023] [Accepted: 01/01/2024] [Indexed: 01/12/2024] Open
Abstract
Translation elongation factor 1A (eEF1A) is an essential and highly conserved protein required for protein synthesis in eukaryotes. In both Saccharomyces cerevisiae and human, five different methyltransferases methylate specific residues on eEF1A, making eEF1A the eukaryotic protein targeted by the highest number of dedicated methyltransferases after histone H3. eEF1A methyltransferases are highly selective enzymes, only targeting eEF1A and each targeting just one or two specific residues in eEF1A. However, the mechanism of this selectivity remains poorly understood. To reveal how S. cerevisiae elongation factor methyltransferase 4 (Efm4) specifically methylates eEF1A at K316, we have used AlphaFold-Multimer modeling in combination with crosslinking mass spectrometry (XL-MS) and enzyme mutagenesis. We find that a unique beta-hairpin motif, which extends out from the core methyltransferase fold, is important for the methylation of eEF1A K316 in vitro. An alanine mutation of a single residue on this beta-hairpin, F212, significantly reduces Efm4 activity in vitro and in yeast cells. We show that the equivalent residue in human eEF1A-KMT2 (METTL10), F220, is also important for its activity towards eEF1A in vitro. We further show that the eEF1A guanine nucleotide exchange factor, eEF1Bα, inhibits Efm4 methylation of eEF1A in vitro, likely due to competitive binding. Lastly, we find that phosphorylation of eEF1A at S314 negatively crosstalks with Efm4-mediated methylation of K316. Our findings demonstrate how protein methyltransferases can be highly selective towards a single residue on a single protein in the cell.
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Affiliation(s)
- Joshua J Hamey
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, New South Wales, Australia.
| | - Amy Nguyen
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, New South Wales, Australia
| | - Mahdi Haddad
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, New South Wales, Australia
| | - Xabier Vázquez-Campos
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, New South Wales, Australia
| | - Paige G Pfeiffer
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, New South Wales, Australia
| | - Marc R Wilkins
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, New South Wales, Australia
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2
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Hedtke T, Mende M, Steenbock H, Brinckmann J, Menzel M, Hoehenwarter W, Pietzsch M, Groth T, Schmelzer CEH. Fabrication of Insoluble Elastin by Enzyme-Free Cross-Linking. Macromol Biosci 2023; 23:e2300203. [PMID: 37441796 DOI: 10.1002/mabi.202300203] [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: 05/10/2023] [Revised: 07/05/2023] [Accepted: 07/07/2023] [Indexed: 07/15/2023]
Abstract
Elastin is an essential extracellular matrix protein that enables tissues and organs such as arteries, lungs, and skin, which undergo continuous deformation, to stretch and recoil. Here, an approach to fabricating artificial elastin with close-to-native molecular and mechanical characteristics is described. Recombinantly produced tropoelastin are polymerized through coacervation and allysine-mediated cross-linking induced by pyrroloquinoline quinone (PQQ). A technique that allows the recovery and repeated use of PQQ for protein cross-linking by covalent attachment to magnetic Sepharose beads is developed. The produced material closely resembles natural elastin in its molecular, biochemical, and mechanical properties, enabled by the occurrence of the cross-linking amino acids desmosine, isodesmosine, and merodesmosine. It possesses elevated resistance against tryptic proteolysis, and its Young's modulus ranging between 1 and 2 MPa is similar to that of natural elastin. The approach described herein enables the engineering of mechanically resilient, elastin-like materials for biomedical applications.
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Affiliation(s)
- Tobias Hedtke
- Department of Biological and Macromolecular Materials, Fraunhofer Institute for Microstructure of Materials and Systems IMWS, 06120, Halle (Saale), Germany
- Institute of Pharmacy, Faculty of Natural Sciences I, Martin Luther University Halle-Wittenberg, Halle (Saale), 06120, Halle (Saale), Germany
| | - Mathias Mende
- Institute of Pharmacy, Faculty of Natural Sciences I, Martin Luther University Halle-Wittenberg, Halle (Saale), 06120, Halle (Saale), Germany
| | - Heiko Steenbock
- Institute of Virology and Cell Biology, University of Lübeck, 23562, Lübeck, Germany
| | - Jürgen Brinckmann
- Institute of Virology and Cell Biology, University of Lübeck, 23562, Lübeck, Germany
- Department of Dermatology, University of Lübeck, 23538, Lübeck, Germany
| | - Matthias Menzel
- Department of Biological and Macromolecular Materials, Fraunhofer Institute for Microstructure of Materials and Systems IMWS, 06120, Halle (Saale), Germany
| | - Wolfgang Hoehenwarter
- Proteome Analytics Research Group, Leibniz Institute for Plant Biochemistry, 06120, Halle (Saale), Germany
| | - Markus Pietzsch
- Institute of Pharmacy, Faculty of Natural Sciences I, Martin Luther University Halle-Wittenberg, Halle (Saale), 06120, Halle (Saale), Germany
- Institute of Applied Dermatopharmacy at the Martin Luther University Halle-Wittenberg (IADP), 06120, Halle (Saale), Germany
| | - Thomas Groth
- Institute of Pharmacy, Faculty of Natural Sciences I, Martin Luther University Halle-Wittenberg, Halle (Saale), 06120, Halle (Saale), Germany
- Interdisciplinary Center of Materials Science, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Christian E H Schmelzer
- Department of Biological and Macromolecular Materials, Fraunhofer Institute for Microstructure of Materials and Systems IMWS, 06120, Halle (Saale), Germany
- Institute of Pharmacy, Faculty of Natural Sciences I, Martin Luther University Halle-Wittenberg, Halle (Saale), 06120, Halle (Saale), Germany
- Institute of Applied Dermatopharmacy at the Martin Luther University Halle-Wittenberg (IADP), 06120, Halle (Saale), Germany
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3
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Sahlström P, Joshua V, Valkovskaia V, Biese C, Stålesen R, Israelsson L, Végvári Á, Scheel-Toellner D, Klareskog L, Hansson M, Hensvold A, Malmström V, Grönwall C. Autoreactive B cells against malondialdehyde-induced protein cross-links are present in the joint, lung, and bone marrow of rheumatoid arthritis patients. J Biol Chem 2023; 299:105320. [PMID: 37802315 PMCID: PMC10641667 DOI: 10.1016/j.jbc.2023.105320] [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: 08/24/2023] [Accepted: 09/28/2023] [Indexed: 10/08/2023] Open
Abstract
Autoantibodies to malondialdehyde (MDA) proteins constitute a subset of anti-modified protein autoantibodies in rheumatoid arthritis (RA), which is distinct from citrulline reactivity. Serum anti-MDA IgG levels are commonly elevated in RA and correlate with disease activity, CRP, IL6, and TNF-α. MDA is an oxidation-associated reactive aldehyde that together with acetaldehyde mediates formation of various immunogenic amino acid adducts including linear MDA-lysine, fluorescent malondialdehyde acetaldehyde (MAA)-lysine, and intramolecular cross-linking. We used single-cell cloning, generation of recombinant antibodies (n = 356 from 25 donors), and antigen-screening to investigate the presence of class-switched MDA/MAA+ B cells in RA synovium, bone marrow, and bronchoalveolar lavage. Anti-MDA/MAA+ B cells were found in bone marrow plasma cells of late disease and in the lung of both early disease and risk-individuals and in different B cell subsets (memory, double negative B cells). These were compared with previously identified anti-MDA/MAA from synovial memory and plasma cells. Seven out of eight clones carried somatic hypermutations and all bound MDA/MAA-lysine independently of protein backbone. However, clones with somatic hypermutations targeted MAA cross-linked structures rather than MDA- or MAA-hapten, while the germline-encoded synovial clone instead bound linear MDA-lysine in proteins and peptides. Binding patterns were maintained in germline converted clones. Affinity purification of polyclonal anti-MDA/MAA from patient serum revealed higher proportion of anti-MAA versus anti-MDA compared to healthy controls. In conclusion, IgG anti-MDA/MAA show distinct targeting of different molecular structures. Anti-MAA IgG has been shown to promote bone loss and osteoclastogenesis in vivo and may contribute to RA pathogenesis.
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Affiliation(s)
- Peter Sahlström
- Division of Rheumatology, Department of Medicine, Center for Molecular Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Vijay Joshua
- Division of Rheumatology, Department of Medicine, Center for Molecular Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Viktoriia Valkovskaia
- Division of Rheumatology, Department of Medicine, Center for Molecular Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Charlotte Biese
- Division of Rheumatology, Department of Medicine, Center for Molecular Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Ragnhild Stålesen
- Division of Rheumatology, Department of Medicine, Center for Molecular Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Lena Israelsson
- Division of Rheumatology, Department of Medicine, Center for Molecular Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Ákos Végvári
- Division of Chemistry I, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Dagmar Scheel-Toellner
- Rheumatology Research Group, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Lars Klareskog
- Division of Rheumatology, Department of Medicine, Center for Molecular Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Monika Hansson
- Division of Rheumatology, Department of Medicine, Center for Molecular Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Aase Hensvold
- Division of Rheumatology, Department of Medicine, Center for Molecular Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden; Center for Rheumatology, Academic Specialist Center, Stockholm Health Region, Stockholm, Sweden
| | - Vivianne Malmström
- Division of Rheumatology, Department of Medicine, Center for Molecular Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Caroline Grönwall
- Division of Rheumatology, Department of Medicine, Center for Molecular Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
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4
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Kumar A, Estrada DF. Structural basis of bidirectional allostery across the heme in a cytochrome P450 enzyme. J Biol Chem 2023; 299:104977. [PMID: 37390989 PMCID: PMC10416055 DOI: 10.1016/j.jbc.2023.104977] [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: 03/06/2023] [Revised: 06/02/2023] [Accepted: 06/22/2023] [Indexed: 07/02/2023] Open
Abstract
Cytochromes P450 (CYPs) are heme-containing enzymes that are present in all kingdoms of life and share a structurally homologous, globular protein fold. CYPs utilize structures distal to the heme to recognize and coordinate substrates, while the necessary interactions with redox partner proteins are mediated at the opposite, proximal surface. In the current study, we investigated the functional allostery across the heme for the bacterial enzyme CYP121A1, which utilizes a non-polar distal-to-distal dimer interface for specific binding of its dicyclotyrosine substrate. Fluorine-detected Nuclear Magnetic Resonance (19F-NMR) spectroscopy was combined with site-specific labeling of a distal surface residue (S171C of the FG-loop), one residue of the B-helix (N84C), and two proximal surface residues (T103C and T333C) with a thiol-reactive fluorine label. Adrenodoxin was used as a substitute redox protein and was found to promote a closed arrangement of the FG-loop, similar to the addition of substrate alone. Disruption of the protein-protein interface by mutagenesis of two CYP121 basic surface residues removed the allosteric effect. Moreover, 19F-NMR spectra of the proximal surface indicate that ligand-induced allostery modulates the environment at the C-helix but not the meander region of the enzyme. In light of the high degree of structural homology in this family of enzymes, we interpret the findings from this work to represent a conserved allosteric network in CYPs.
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Affiliation(s)
- Amit Kumar
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Science, University at Buffalo, Buffalo, New York, USA
| | - D Fernando Estrada
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Science, University at Buffalo, Buffalo, New York, USA.
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5
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Almugadam SH, Trentini A, Maritati M, Contini C, Manfrinato MC, Cervellati C, Bellini T, Hanau S. A Calcium- and GTP-Dependent Transglutaminase in Leishmania infantum. Vet Sci 2023; 10:vetsci10030234. [PMID: 36977273 PMCID: PMC10053793 DOI: 10.3390/vetsci10030234] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 03/10/2023] [Accepted: 03/15/2023] [Indexed: 03/30/2023] Open
Abstract
While human and animal leishmaniasis affect several millions of people worldwide, L. infantum is the species responsible for visceral leishmaniasis in Europe, Middle East, and America. Antileishmanial drugs present issues associated with drug toxicity and increasing parasite resistance. Therefore, the study of this parasite with a focus on new potential drug targets is extremely useful. Accordingly, we purified and characterized a transglutaminase (TGase) from L. infantum promastigotes. While Tgases are known to be involved in cell death and autophagy, it appears that these functions are very important for parasites' virulence. For the first time, we showed a Ca2+- and GTP-dependent TGase in Leishmania corresponding to a 54 kDa protein, which was purified by two chromatographic steps: DEAE-Sepharose and Heparin-Sepharose. Using polyclonal antibodies against a 50-amino-acid conserved region of the catalytic core of human TGase 2, we revealed two other bands of 66 and 75 kDa. The 54 kDa band appears to be different from the previously reported TGase, which was shown to be Ca2+- independent. Future research should address the identification of the purified enzyme sequence and, subsequently, its cloning to more comprehensively investigate its pathophysiological function and possible differences from mammal enzymes.
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Affiliation(s)
- Shawgi Hago Almugadam
- Department of Neuroscience and Rehabilitation, University of Ferrara, Via Luigi Borsari 46, 44121 Ferrara, Italy
- Faculty of Medical Laboratory Sciences, University of Khartoum, Nile Avenue, P.O. Box 321, Khartoum 51111, Sudan
| | - Alessandro Trentini
- Department of Environmental and Prevention Sciences, University of Ferrara, Via Luigi Borsari 46, 44121 Ferrara, Italy
| | - Martina Maritati
- Infectious Diseases and Dermatology, Department of Medical Sciences, University of Ferrara, Via Aldo Moro 8, 44124 Ferrara, Italy
| | - Carlo Contini
- Infectious Diseases and Dermatology, Department of Medical Sciences, University of Ferrara, Via Aldo Moro 8, 44124 Ferrara, Italy
| | - Maria Cristina Manfrinato
- Department of Neuroscience and Rehabilitation, University of Ferrara, Via Luigi Borsari 46, 44121 Ferrara, Italy
| | - Carlo Cervellati
- Department of Translational Medicine and for Romagna, University of Ferrara, Via Luigi Borsari 46, 44121 Ferrara, Italy
| | - Tiziana Bellini
- Department of Neuroscience and Rehabilitation, University of Ferrara, Via Luigi Borsari 46, 44121 Ferrara, Italy
| | - Stefania Hanau
- Department of Neuroscience and Rehabilitation, University of Ferrara, Via Luigi Borsari 46, 44121 Ferrara, Italy
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6
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Yu N, Xu J, Huang B, Nie X, Lu Y, Ye Q, Meng X. Partial substitution of whey protein concentrate by zein in high-protein nutrition bars: An effective method to reduce hardening during storage. J Food Sci 2023; 88:1420-1429. [PMID: 36880580 DOI: 10.1111/1750-3841.16515] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 01/14/2023] [Accepted: 02/14/2023] [Indexed: 03/08/2023]
Abstract
Whey protein concentrate-based high-protein nutrition bars (WPC-based HPN bars) are prone to hardening during storage, which limits their shelf life. In this study, zein was introduced to partially substitute WPC in the WPC-based HPN bars. The result of storage experiment revealed that the hardening of WPC-based HPN bars was significantly reduced with increasing zein content from 0% to 20% (mass ratio, zein:WPC-based HPN bar). Subsequently, the possible anti-hardening mechanism of zein substitution was studied in detail by determining the change in microstructure, patterns, free sulfhydryl group, color, free amino group, and Fourier transform infrared spectra of WPC-based HPN bars during storage. The results showed that zein substitution significantly blocked protein aggregation by inhibiting cross-linking, the Maillard reaction, and protein secondary structure transformation from α-helix to β-sheet, which reduced the hardening of WPC-based HPN bars. This work provides insight into the potential utilization of zein substitution to improve the quality and shelf life of WPC-based HPN bars. PRACTICAL APPLICATION: In the preparation of whey protein concentrate-based high-protein nutrition bars, the introduction of zein to partially replace WPC can effectively reduce the hardening of WPC-based HPN bars during storage by preventing protein aggregation between WPC macromolecules. Therefore, zein could act as an agent to reduce the hardening of WPC-based HPN bars.
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Affiliation(s)
- Ningxiang Yu
- College of Food Science and Technology, Zhejiang University of Technology, Hangzhou, Zhejiang, China
| | - Jinhua Xu
- College of Food Science and Technology, Zhejiang University of Technology, Hangzhou, Zhejiang, China
| | - Baozhu Huang
- College of Food Science and Technology, Zhejiang University of Technology, Hangzhou, Zhejiang, China
| | - Xiaohua Nie
- College of Food Science and Technology, Zhejiang University of Technology, Hangzhou, Zhejiang, China
| | - Yuanchao Lu
- College of Food Science and Technology, Zhejiang University of Technology, Hangzhou, Zhejiang, China
| | - Qin Ye
- College of Biology and Environmental Engineering, Zhejiang Shuren University, Hangzhou, China
| | - Xianghe Meng
- College of Food Science and Technology, Zhejiang University of Technology, Hangzhou, Zhejiang, China
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7
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Long M, Zheng N, Zhang Z, Gao L, Wang Y, Xia X. [Mechanisms and applications of enzyme-catalyzed protein cross-linking]. Sheng Wu Gong Cheng Xue Bao 2022; 38:2499-2512. [PMID: 35871620 DOI: 10.13345/j.cjb.210875] [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] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Protein cross-linking plays important roles in food, chemical, medicine and other fields. Enzyme-catalyzed protein cross-linking is an efficient and economically viable alternative to physical and chemical cross-linking. However, detailed analysis of enzyme-catalyzed protein cross-linking at molecular level is still lacking. This review summarized the mechanisms of enzyme-catalyzed protein cross-linking, its effects on protein structure, and its applications in food, chemical and pharmaceutical fields.
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Affiliation(s)
- Mengfei Long
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, Jiangsu, China
- School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Nan Zheng
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, Jiangsu, China
- School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Zehua Zhang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, Jiangsu, China
- School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Ling Gao
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, Jiangsu, China
- School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Yingyu Wang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, Jiangsu, China
- School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Xiaole Xia
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, Jiangsu, China
- School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
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8
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Chen CY, Zhang JQ, Li L, Guo MM, He YF, Dong YM, Meng H, Yi F. Advanced Glycation End Products in the Skin: Molecular Mechanisms, Methods of Measurement, and Inhibitory Pathways. Front Med (Lausanne) 2022; 9:837222. [PMID: 35646963 PMCID: PMC9131003 DOI: 10.3389/fmed.2022.837222] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [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: 12/16/2021] [Accepted: 04/21/2022] [Indexed: 12/19/2022] Open
Abstract
Advanced glycation end products (AGEs) are a series of stable compounds produced under non-enzymatic conditions by the amino groups of biomacromolecules and the free carbonyl groups of glucose or other reducing sugars commonly produced by thermally processed foods. AGEs can cause various diseases, such as diabetes, atherosclerosis, neurodegeneration, and chronic kidney disease, by triggering the receptors of AGE (RAGEs) in the human body. There is evidence that AGEs can also affect the different structures and physiological functions of the skin. However, the mechanism is complicated and cumbersome and causes various harms to the skin. This article aims to identify and summarise the formation and characteristics of AGEs, focussing on the molecular mechanisms by which AGEs affect the composition and structure of normal skin substances at different skin layers and induce skin issues. We also discuss prevention and inhibition pathways, provide a systematic and comprehensive method for measuring the content of AGEs in human skin, and summarise and analyse their advantages and disadvantages. This work can help researchers acquire a deeper understanding of the relationship between AGEs and the skin and provides a basis for the development of effective ingredients that inhibit glycation.
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Affiliation(s)
- Chun-Yu Chen
- Beijing Key Laboratory of Plant Resources Research and Development, Beijing Technology and Business University, Beijing, China.,Key Laboratory of Cosmetic, China National Light Industry, Beijing Technology and Business University, Beijing, China.,Institute of Cosmetic Regulatory Science, Beijing Technology and Business University, Beijng, China
| | - Jia-Qi Zhang
- Beijing Key Laboratory of Plant Resources Research and Development, Beijing Technology and Business University, Beijing, China.,Key Laboratory of Cosmetic, China National Light Industry, Beijing Technology and Business University, Beijing, China.,Institute of Cosmetic Regulatory Science, Beijing Technology and Business University, Beijng, China
| | - Li Li
- Beijing Key Laboratory of Plant Resources Research and Development, Beijing Technology and Business University, Beijing, China.,Key Laboratory of Cosmetic, China National Light Industry, Beijing Technology and Business University, Beijing, China.,Institute of Cosmetic Regulatory Science, Beijing Technology and Business University, Beijng, China
| | - Miao-Miao Guo
- Beijing Key Laboratory of Plant Resources Research and Development, Beijing Technology and Business University, Beijing, China.,Key Laboratory of Cosmetic, China National Light Industry, Beijing Technology and Business University, Beijing, China.,Institute of Cosmetic Regulatory Science, Beijing Technology and Business University, Beijng, China
| | - Yi-Fan He
- Beijing Key Laboratory of Plant Resources Research and Development, Beijing Technology and Business University, Beijing, China.,Key Laboratory of Cosmetic, China National Light Industry, Beijing Technology and Business University, Beijing, China.,Institute of Cosmetic Regulatory Science, Beijing Technology and Business University, Beijng, China
| | - Yin-Mao Dong
- Beijing Key Laboratory of Plant Resources Research and Development, Beijing Technology and Business University, Beijing, China.,Key Laboratory of Cosmetic, China National Light Industry, Beijing Technology and Business University, Beijing, China.,Institute of Cosmetic Regulatory Science, Beijing Technology and Business University, Beijng, China
| | - Hong Meng
- Beijing Key Laboratory of Plant Resources Research and Development, Beijing Technology and Business University, Beijing, China.,Key Laboratory of Cosmetic, China National Light Industry, Beijing Technology and Business University, Beijing, China.,Institute of Cosmetic Regulatory Science, Beijing Technology and Business University, Beijng, China
| | - Fan Yi
- Beijing Key Laboratory of Plant Resources Research and Development, Beijing Technology and Business University, Beijing, China.,Key Laboratory of Cosmetic, China National Light Industry, Beijing Technology and Business University, Beijing, China.,Institute of Cosmetic Regulatory Science, Beijing Technology and Business University, Beijng, China
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9
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Lockey C, Young H, Brown J, Dixon AM. Characterization of interactions within the Igα/Igβ transmembrane domains of the human B-cell receptor provides insights into receptor assembly. J Biol Chem 2022;:101843. [PMID: 35307351 DOI: 10.1016/j.jbc.2022.101843] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [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: 09/14/2021] [Revised: 03/10/2022] [Accepted: 03/11/2022] [Indexed: 12/04/2022] Open
Abstract
The B-cell receptor (BCR), a complex comprised of a membrane-associated immunoglobulin and the Igα/β heterodimer, is one of the most important immune receptors in humans and controls B-cell development, activity, selection, and death. BCR signaling plays key roles in autoimmune diseases and lymphoproliferative disorders, yet, despite the clinical significance of this protein complex, key regions (i.e., the transmembrane domains) have yet to be structurally characterized. The mechanism for BCR signaling also remains unclear and has been variously described by the mutually exclusive cross-linking and dissociation activation models. Common to these models is the significance of local plasma membrane composition, which implies that interactions between BCR transmembrane domains (TMDs) play a role in receptor functionality. Here we used an in vivo assay of TMD oligomerization called GALLEX alongside spectroscopic and computational methods to characterize the structures and interactions of human Igα and Igβ TMDs in detergent micelles and natural membranes. We observed weak self-association of the Igβ TMD and strong self-association of the Igα TMD, which scanning mutagenesis revealed was entirely stabilized by an E–X10–P motif. We also demonstrated strong heterotypic interactions between the Igα and Igβ TMDs both in vitro and in vivo, which scanning mutagenesis and computational models suggest is multiconfigurational but can accommodate distinct interaction sites for self-interactions and heterotypic interactions of the Igα TMD. Taken together, these results demonstrate that the TMDs of the human BCR are sites of strong protein–protein interactions that may direct BCR assembly, endoplasmic reticulum retention, and immune signaling.
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10
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Domínguez R, Pateiro M, Munekata PES, Zhang W, Garcia-Oliveira P, Carpena M, Prieto MA, Bohrer B, Lorenzo JM. Protein Oxidation in Muscle Foods: A Comprehensive Review. Antioxidants (Basel) 2021; 11:60. [PMID: 35052564 PMCID: PMC8773412 DOI: 10.3390/antiox11010060] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [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: 11/25/2021] [Revised: 12/23/2021] [Accepted: 12/25/2021] [Indexed: 12/26/2022] Open
Abstract
Muscle foods and their products are a fundamental part of the human diet. The high protein content found in muscle foods, as well as the high content of essential amino acids, provides an appropriate composition to complete the nutritional requirements of humans. However, due to their special composition, they are susceptible to oxidative degradation. In this sense, proteins are highly susceptible to oxidative reactions. However, in contrast to lipid oxidation, which has been studied in depth for decades, protein oxidation of muscle foods has been investigated much less. Moreover, these reactions have an important influence on the quality of muscle foods, from physico-chemical, techno-functional, and nutritional perspectives. In this regard, the loss of essential nutrients, the impairment of texture, water-holding capacity, color and flavor, and the formation of toxic substances are some of the direct consequences of protein oxidation. The loss of quality for muscle foods results in consumer rejection and substantial levels of economic losses, and thus the control of oxidative processes is of vital importance for the food industry. Nonetheless, the complexity of the reactions involved in protein oxidation and the many different factors that influence these reactions make the mechanisms of protein oxidation difficult to fully understand. Therefore, the present manuscript reviews the fundamental mechanisms of protein oxidation, the most important oxidative reactions, the main factors that influence protein oxidation, and the currently available analytical methods to quantify compounds derived from protein oxidation reactions. Finally, the main effects of protein oxidation on the quality of muscle foods, both from physico-chemical and nutritional points of view, are also discussed.
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Affiliation(s)
- Rubén Domínguez
- Centro Tecnológico de la Carne de Galicia, Rúa Galicia Nº 4, Parque Tecnológico de Galicia, 32900 San Cibrao das Vinas, Spain; (R.D.); (M.P.); (P.E.S.M.)
| | - Mirian Pateiro
- Centro Tecnológico de la Carne de Galicia, Rúa Galicia Nº 4, Parque Tecnológico de Galicia, 32900 San Cibrao das Vinas, Spain; (R.D.); (M.P.); (P.E.S.M.)
| | - Paulo E. S. Munekata
- Centro Tecnológico de la Carne de Galicia, Rúa Galicia Nº 4, Parque Tecnológico de Galicia, 32900 San Cibrao das Vinas, Spain; (R.D.); (M.P.); (P.E.S.M.)
| | - Wangang Zhang
- Key Laboratory of Meat Processing and Quality Control, Ministry of Education China, Jiangsu Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
| | - Paula Garcia-Oliveira
- Nutrition and Bromatology Group, Analytical and Food Chemistry Department, Faculty of Food Science and Technology, University of Vigo, 32004 Ourense, Spain; (P.G.-O.); (M.C.); (M.A.P.)
- Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, Campus de Santa Apolonia, 5300-253 Braganca, Portugal
| | - Maria Carpena
- Nutrition and Bromatology Group, Analytical and Food Chemistry Department, Faculty of Food Science and Technology, University of Vigo, 32004 Ourense, Spain; (P.G.-O.); (M.C.); (M.A.P.)
| | - Miguel A. Prieto
- Nutrition and Bromatology Group, Analytical and Food Chemistry Department, Faculty of Food Science and Technology, University of Vigo, 32004 Ourense, Spain; (P.G.-O.); (M.C.); (M.A.P.)
- Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, Campus de Santa Apolonia, 5300-253 Braganca, Portugal
| | - Benjamin Bohrer
- Department of Animal Sciences, The Ohio State University, Columbus, OH 43210, USA;
| | - José M. Lorenzo
- Centro Tecnológico de la Carne de Galicia, Rúa Galicia Nº 4, Parque Tecnológico de Galicia, 32900 San Cibrao das Vinas, Spain; (R.D.); (M.P.); (P.E.S.M.)
- Facultade de Ciencias, Área de Tecnoloxía dos Alimentos, Universidade de Vigo, 32004 Ourense, Spain
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11
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Abstract
One crucial aspect of the Maillard reaction is the formation of reactive α-dicarbonyl structures like glyoxal, which are prone toward further reactions with proteins, e.g., the N6-amino group of lysine. The initially formed labile glyoxal-imine was previously established as a key intermediate in the formation of the advanced glycation end products N6-carboxymethyl lysine (CML), glyoxal lysine amide (GOLA), glyoxal lysine dimer (GOLD), and N6-glycolyl lysine (GALA). Here, we introduce a novel amidine cross-link structure N1,N2-bis-(5-amino-5-carboxypentyl)-2-hydroxy-acetamidine (glyoxal lysine amidine, GLA), which is formed exclusively from glyoxal through the same isomerization cascade. After independent synthesis of the authentic reference standard, we were able to quantitate this cross-link in incubations of 40 mM N2-t-Boc-lysine with glyoxal and various sugars (40-100 mM) under mild conditions (pH 7.4, 37 °C) using an HPLC-MS/MS method. Furthermore, incubations of proteins (6 mg/mL) with 50 mM glyoxal confirmed the cross-linking by GLA, which was additionally identified in acidic hydrolyzed proteins of butter biscuits after HPLC enrichment.
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Affiliation(s)
- Michael D Eggen
- Institute of Chemistry, Food Chemistry, Martin-Luther-University Halle-Wittenberg, Kurt-Mothes-Str. 2, Halle/Saale 06120, Germany
| | - Marcus A Glomb
- Institute of Chemistry, Food Chemistry, Martin-Luther-University Halle-Wittenberg, Kurt-Mothes-Str. 2, Halle/Saale 06120, Germany
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12
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Nielsen NS, Gadeberg TAF, Poulsen ET, Harwood SL, Weberskov CE, Pedersen JS, Andersen GR, Enghild JJ. Mutation-induced dimerization of transforming growth factor-β-induced protein may drive protein aggregation in granular corneal dystrophy. J Biol Chem 2021; 297:100858. [PMID: 34097874 DOI: 10.1016/j.jbc.2021.100858] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [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: 12/16/2020] [Revised: 05/23/2021] [Accepted: 06/03/2021] [Indexed: 11/21/2022] Open
Abstract
Protein aggregation in the outermost layers of the cornea, which can lead to cloudy vision and in severe cases blindness, is linked to mutations in the extracellular matrix protein transforming growth factor-β-induced protein (TGFBIp). Among the most frequent pathogenic mutations are R124H and R555W, both associated with granular corneal dystrophy (GCD) characterized by the early-onset formation of amorphous aggregates. The molecular mechanisms of protein aggregation in GCD are largely unknown. In this study, we determined the crystal structures of R124H, R555W, and the lattice corneal dystrophy-associated A546T. Although there were no changes in the monomeric TGFBIp structure of any mutant that would explain their propensity to aggregate, R124H and R555W demonstrated a new dimer interface in the crystal packing, which is not present in wildtype TGFBIp or A546T. This interface, as seen in both the R124H and R555W structures, involves residue 124 of the first TGFBIp molecule and 555 in the second. The interface is not permitted by the Arg124 and Arg555 residues of wildtype TGFBIp and may play a central role in the aggregation exhibited by R124H and R555W in vivo. Using cross-linking mass spectrometry and in-line size exclusion chromatography-small-angle X-ray scattering, we characterized a dimer formed by wildtype and mutant TGFBIps in solution. Dimerization in solution also involves interactions between the N- and C-terminal domains of two TGFBIp molecules but was not identical to the crystal packing dimerization. TGFBIp-targeted interventions that disrupt the R124H/R555W crystal packing dimer interface might offer new therapeutic opportunities to treat patients with GCD.
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Harwood SL, Lyngsø J, Zarantonello A, Kjøge K, Nielsen PK, Andersen GR, Pedersen JS, Enghild JJ. Structural Investigations of Human A2M Identify a Hollow Native Conformation That Underlies Its Distinctive Protease-Trapping Mechanism. Mol Cell Proteomics 2021; 20:100090. [PMID: 33964423 PMCID: PMC8167298 DOI: 10.1016/j.mcpro.2021.100090] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [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] [Received: 01/19/2021] [Revised: 04/07/2021] [Accepted: 05/02/2021] [Indexed: 12/21/2022] Open
Abstract
Human α2-macroglobulin (A2M) is the most characterized protease inhibitor in the alpha-macroglobulin (αM) superfamily, but the structure of its native conformation has not been determined. Here, we combined negative stain electron microscopy (EM), small-angle X-ray scattering (SAXS), and cross-linking-mass spectrometry (XL-MS) to investigate native A2M and its collapsed conformations that are obtained through aminolysis of its thiol ester by methylamine or cleavage of its bait region by trypsin. The combined interpretation of these data resulted in a model of the native A2M tetramer and its conformational changes. Native A2M consists of two crescent-shaped disulfide-bridged subunit dimers, which face toward each other and surround a central hollow space. In native A2M, interactions across the disulfide-bridged dimers are minimal, with a single major interface between the linker (LNK) regions of oppositely positioned subunits. Bait region cleavage induces both intrasubunit domain repositioning and an altered configuration of the disulfide-bridged dimer. These changes collapse the tetramer into a more compact conformation, which encloses an interior protease-trapping cavity. A recombinant A2M with a modified bait region was used to map the bait region's position in native A2M by XL-MS. A second recombinant A2M introduced an intersubunit disulfide into the LNK region, demonstrating the predicted interactions between these regions in native A2M. Altogether, our native A2M model provides a structural foundation for understanding A2M's protease-trapping mechanism, its conformation-dependent receptor interactions, and the dissociation of native A2M into dimers due to inflammatory oxidative stress.
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Affiliation(s)
- Seandean Lykke Harwood
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark; Global Research Technologies, Novo Nordisk A/S, Måløv, Denmark
| | - Jeppe Lyngsø
- Interdisciplinary Nanoscience Center, Aarhus University, Aarhus, Denmark; Department of Chemistry, Aarhus University, Aarhus, Denmark
| | | | - Katarzyna Kjøge
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | | | - Gregers Rom Andersen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Jan Skov Pedersen
- Interdisciplinary Nanoscience Center, Aarhus University, Aarhus, Denmark; Department of Chemistry, Aarhus University, Aarhus, Denmark.
| | - Jan J Enghild
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark; Interdisciplinary Nanoscience Center, Aarhus University, Aarhus, Denmark.
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Nemeria NS, Zhang X, Leandro J, Zhou J, Yang L, Houten SM, Jordan F. Toward an Understanding of the Structural and Mechanistic Aspects of Protein-Protein Interactions in 2-Oxoacid Dehydrogenase Complexes. Life (Basel) 2021; 11:life11050407. [PMID: 33946784 PMCID: PMC8146983 DOI: 10.3390/life11050407] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [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: 04/03/2021] [Revised: 04/21/2021] [Accepted: 04/22/2021] [Indexed: 12/24/2022] Open
Abstract
The 2-oxoglutarate dehydrogenase complex (OGDHc) is a key enzyme in the tricarboxylic acid (TCA) cycle and represents one of the major regulators of mitochondrial metabolism through NADH and reactive oxygen species levels. The OGDHc impacts cell metabolic and cell signaling pathways through the coupling of 2-oxoglutarate metabolism to gene transcription related to tumor cell proliferation and aging. DHTKD1 is a gene encoding 2-oxoadipate dehydrogenase (E1a), which functions in the L-lysine degradation pathway. The potentially damaging variants in DHTKD1 have been associated to the (neuro) pathogenesis of several diseases. Evidence was obtained for the formation of a hybrid complex between the OGDHc and E1a, suggesting a potential cross talk between the two metabolic pathways and raising fundamental questions about their assembly. Here we reviewed the recent findings and advances in understanding of protein-protein interactions in OGDHc and 2-oxoadipate dehydrogenase complex (OADHc), an understanding that will create a scaffold to help design approaches to mitigate the effects of diseases associated with dysfunction of the TCA cycle or lysine degradation. A combination of biochemical, biophysical and structural approaches such as chemical cross-linking MS and cryo-EM appears particularly promising to provide vital information for the assembly of 2-oxoacid dehydrogenase complexes, their function and regulation.
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Affiliation(s)
- Natalia S. Nemeria
- Department of Chemistry, Rutgers, The State University of New Jersey, Newark, NJ 07102, USA; (J.Z.); (L.Y.)
- Correspondence: (N.S.N.); (X.Z.); (F.J.)
| | - Xu Zhang
- Department of Chemistry, Rutgers, The State University of New Jersey, Newark, NJ 07102, USA; (J.Z.); (L.Y.)
- Correspondence: (N.S.N.); (X.Z.); (F.J.)
| | - Joao Leandro
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (J.L.); (S.M.H.)
| | - Jieyu Zhou
- Department of Chemistry, Rutgers, The State University of New Jersey, Newark, NJ 07102, USA; (J.Z.); (L.Y.)
| | - Luying Yang
- Department of Chemistry, Rutgers, The State University of New Jersey, Newark, NJ 07102, USA; (J.Z.); (L.Y.)
| | - Sander M. Houten
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (J.L.); (S.M.H.)
| | - Frank Jordan
- Department of Chemistry, Rutgers, The State University of New Jersey, Newark, NJ 07102, USA; (J.Z.); (L.Y.)
- Correspondence: (N.S.N.); (X.Z.); (F.J.)
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15
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Spencer PS, Chen X. The Role of Protein Adduction in Toxic Neuropathies of Exogenous and Endogenous Origin. Toxics 2021; 9:toxics9050098. [PMID: 33946924 PMCID: PMC8146965 DOI: 10.3390/toxics9050098] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 04/20/2021] [Accepted: 04/24/2021] [Indexed: 02/07/2023]
Abstract
The peripheral (axonal) neuropathy associated with repeated exposure to aliphatic and aromatic solvents that form protein-reactive γ-diketones shares some clinical and neuropathological features with certain metabolic neuropathies, including type-II diabetic neuropathy and uremic neuropathy, and with the largely sub-clinical nerve damage associated with old age. These conditions may be linked by metabolites that adduct and cross-link neuroproteins required for the maintenance of axonal transport and nerve fiber integrity in the peripheral and central nervous system.
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Affiliation(s)
- Peter S. Spencer
- Department of Neurology, School of Medicine, and Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR 97239, USA
- Correspondence:
| | - Xiao Chen
- Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Medical Key Subject of Health Toxicology (2020–2024), Shenzhen Center for Disease Control and Prevention, Shenzhen 518055, China;
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16
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Abstract
Coral skeletons are materials composed of inorganic aragonitic fibres and organic molecules including proteins, sugars and lipids that are highly organized to form a solid biomaterial upon which the animals live. The skeleton contains tens of proteins, all of which are encoded in the animal genome and secreted during the biomineralization process. While recent advances are revealing the functions and evolutionary history of some of these proteins, how they are spatially arranged in the skeleton is unknown. Using a combination of chemical cross-linking and high-resolution tandem mass spectrometry, we identify, for the first time, the spatial interactions of the proteins embedded within the skeleton of the stony coral Stylophora pistillata. Our subsequent network analysis revealed that several coral acid-rich proteins are invariably associated with carbonic anhydrase(s), alpha-collagen, cadherins and other calcium-binding proteins. These spatial arrangements clearly show that protein-protein interactions in coral skeletons are highly coordinated and are key to understanding the formation and persistence of coral skeletons through time.
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Affiliation(s)
- Manjula P Mummadisetti
- Environmental Biophysics and Molecular Biology Program, Department of Marine and Coastal Sciences, Rutgers, The State University of New Jersey, 71 Dudley Rd, New Brunswick, NJ 08901, USA
| | - Jeana L Drake
- Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, 595 Charles E. Young Drive East, Los Angeles, CA 90095, USA.,Department of Marine Biology, University of Haifa, 199 Aba Khoushy Avenue, Mount Carmel, Haifa 2498838, Israel
| | - Paul G Falkowski
- Environmental Biophysics and Molecular Biology Program, Department of Marine and Coastal Sciences, Rutgers, The State University of New Jersey, 71 Dudley Rd, New Brunswick, NJ 08901, USA.,Department of Earth and Planetary Sciences, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
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17
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Hannß M, Böhm W, Drichel S, Henle T. Acid-Induced Gelation of Enzymatically and Nonenzymatically Cross-Linked Caseins-Texture Properties, and Microstructural Insights. J Agric Food Chem 2020; 68:13970-13981. [PMID: 33147016 DOI: 10.1021/acs.jafc.0c04445] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Casein gels consist of a fractal organized network of aggregated casein particles. The gel texture thereby depends on the structure, the spatial distribution, and the interaction forces of the network's elementary building blocks. The aim of this study was to explore the technofunctional consequences of a possible specificity of Maillard reaction-induced cross-linking reactions on casein with respect to texture and microstructure of acid gels. Therefore, sodium caseinate glycated with lactose in the dry state (60 °C, aw 0.5) was compared with casein samples cross-linked with methylglyoxal, with glutaraldehyde, or via microbial transglutaminase, respectively, at similar levels of protein cross-linking as confirmed by size-exclusion chromatography under denaturing conditions. Casein gels prepared by acidification with glucono-δ-lactone were characterized concerning pH kinetics during gelation, mechanical texture properties under large deformation, and water-holding capacity, while viscometric properties of casein suspensions were obtained prior to gelation. The gel microstructure was captured by confocal laser scanning microscopy and evaluated by means of image texture analysis. All protein cross-linking reactions studied led to an enhanced gel strength which was accompanied by an increased interconnectivity of the gel network and a decrease in apparent pore sizes. Gels with more densely packed strands, as was the case for enzymatically modified casein, exhibited pronounced mechanical stability. The spontaneous destabilization of the gel network upon prolonged glycation reactions, which was not obviously displayed by microstructural features but connected to an increased viscosity and pronounced pseudoplastic flow of the unacidified suspension, suggests a limitation of particle rearrangements and the weakening of interparticle protein-protein interactions by additional structure attributes formed during the early Maillard reaction (glycoconjugation).
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Affiliation(s)
- Mariella Hannß
- Chair of Food Chemistry, Technische Universität Dresden, 01062 Dresden, Germany
| | - Wendelin Böhm
- Chair of Food Chemistry, Technische Universität Dresden, 01062 Dresden, Germany
| | - Sabine Drichel
- Chair of Food Chemistry, Technische Universität Dresden, 01062 Dresden, Germany
| | - Thomas Henle
- Chair of Food Chemistry, Technische Universität Dresden, 01062 Dresden, Germany
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18
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Azar DF, Haas M, Fedosyuk S, Rahaman MH, Hedger A, Kobe B, Skern T. Vaccinia Virus Immunomodulator A46: Destructive Interactions with MAL and MyD88 Shown by Negative-Stain Electron Microscopy. Structure 2020; 28:1271-1287.e5. [PMID: 33035450 DOI: 10.1016/j.str.2020.09.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [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: 05/03/2020] [Revised: 07/27/2020] [Accepted: 09/17/2020] [Indexed: 12/15/2022]
Abstract
Vaccinia virus A46 is an anti-inflammatory and non-anti-apoptotic, two-domain member of the poxviral Bcl-2-like protein family that inhibits the cellular innate immune response at the level of the Toll/interleukin-1 receptor (TIR) domain-containing TLR adaptor proteins MAL, MyD88, TRAM, and TRIF. The mechanism of interaction of A46 with its targets has remained unclear. The TIR domains of MAL and MyD88 have been shown to signal by forming filamentous assemblies. We show a clear concentration-dependent destruction of both of these assemblies by A46 by means of negative-stain electron microscopy from molar ratios of 1:15 for MAL and 1:30 for MyD88. Using targeted mutagenesis and protein-protein crosslinking, we show that A46 interacts with MAL and MyD88 through several facets, including residues on helices α1 and α7 and the C-terminal flexible region. We propose a model in which A46 targets the MAL and MyD88 signalosome intra-strand interfaces and gradually destroys their assemblies in a concentration-dependent manner.
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Affiliation(s)
- Daniel F Azar
- Max Perutz Labs, Medical University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria
| | - Meryl Haas
- Max Perutz Labs, Medical University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria
| | - Sofiya Fedosyuk
- Max Perutz Labs, Medical University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria; Jenner Institute, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Md Habibur Rahaman
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD 4072, Australia
| | - Andrew Hedger
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD 4072, Australia
| | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD 4072, Australia
| | - Tim Skern
- Max Perutz Labs, Medical University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria.
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19
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Stammers M, Ivanova IM, Niewczas IS, Segonds-Pichon A, Streeter M, Spiegel DA, Clark J. Age-related changes in the physical properties, cross-linking, and glycation of collagen from mouse tail tendon. J Biol Chem 2020; 295:10562-10571. [PMID: 32381510 PMCID: PMC7397091 DOI: 10.1074/jbc.ra119.011031] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 05/04/2020] [Indexed: 12/18/2022] Open
Abstract
Collagen is a structural protein whose internal cross-linking critically determines the properties and functions of connective tissue. Knowing how the cross-linking of collagen changes with age is key to understanding why the mechanical properties of tissues change over a lifetime. The current scientific consensus is that collagen cross-linking increases with age and that this increase leads to tendon stiffening. Here, we show that this view should be reconsidered. Using MS-based analyses, we demonstrated that during aging of healthy C57BL/6 mice, the overall levels of collagen cross-linking in tail tendon decreased with age. However, the levels of lysine glycation in collagen, which is not considered a cross-link, increased dramatically with age. We found that in 16-week-old diabetic db/db mice, glycation reaches levels similar to those observed in 98-week-old C57BL/6 mice, while the other cross-links typical of tendon collagen either decreased or remained the same as those observed in 20-week-old WT mice. These results, combined with findings from mechanical testing of tendons from these mice, indicate that overall collagen cross-linking in mouse tendon decreases with age. Our findings also reveal that lysine glycation appears to be an important factor that contributes to tendon stiffening with age and in diabetes.
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Affiliation(s)
| | - Irina M Ivanova
- Babraham Institute, Cambridge, United Kingdom
- John Innes Centre, Norwich, United Kingdom
| | | | | | - Matthew Streeter
- Department of Chemistry, Yale University, New Haven, Connecticut, USA
| | - David A Spiegel
- Department of Chemistry, Yale University, New Haven, Connecticut, USA
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20
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Artz JH, Tokmina-Lukaszewska M, Mulder DW, Lubner CE, Gutekunst K, Appel J, Bothner B, Boehm M, King PW. The structure and reactivity of the HoxEFU complex from the cyanobacterium Synechocystis sp. PCC 6803. J Biol Chem 2020; 295:9445-9454. [PMID: 32409585 PMCID: PMC7363133 DOI: 10.1074/jbc.ra120.013136] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [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: 02/19/2020] [Revised: 05/11/2020] [Indexed: 11/19/2022] Open
Abstract
Cyanobacterial Hox is a [NiFe] hydrogenase that consists of the hydrogen (H2)-activating subunits HoxYH, which form a complex with the HoxEFU assembly to mediate reactions with soluble electron carriers like NAD(P)H and ferredoxin (Fdx), thereby coupling photosynthetic electron transfer to energy-transforming catalytic reactions. Researchers studying the HoxEFUYH complex have observed that HoxEFU can be isolated independently of HoxYH, leading to the hypothesis that HoxEFU is a distinct functional subcomplex rather than an artifact of Hox complex isolation. Moreover, outstanding questions about the reactivity of Hox with natural substrates and the site(s) of substrate interactions and coupling of H2, NAD(P)H, and Fdx remain to be resolved. To address these questions, here we analyzed recombinantly produced HoxEFU by electron paramagnetic resonance spectroscopy and kinetic assays with natural substrates. The purified HoxEFU subcomplex catalyzed electron transfer reactions among NAD(P)H, flavodoxin, and several ferredoxins, thus functioning in vitro as a shuttle among different cyanobacterial pools of reducing equivalents. Both Fdx1-dependent reductions of NAD+ and NADP+ were cooperative. HoxEFU also catalyzed the flavodoxin-dependent reduction of NAD(P)+, Fdx2-dependent oxidation of NADH and Fdx4- and Fdx11-dependent reduction of NAD+. MS-based mapping identified an Fdx1-binding site at the junction of HoxE and HoxF, adjacent to iron-sulfur (FeS) clusters in both subunits. Overall, the reactivity of HoxEFU observed here suggests that it functions in managing peripheral electron flow from photosynthetic electron transfer, findings that reveal detailed insights into how ubiquitous cellular components may be used to allocate energy flow into specific bioenergetic products.
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Affiliation(s)
- Jacob H Artz
- Biosciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
| | | | - David W Mulder
- Biosciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
| | - Carolyn E Lubner
- Biosciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
| | | | - Jens Appel
- Botanical Institute, Christian-Albrechts-University, Kiel, Germany
| | - Brian Bothner
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana, USA
| | - Marko Boehm
- Botanical Institute, Christian-Albrechts-University, Kiel, Germany
| | - Paul W King
- Biosciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
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21
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Ganesan SJ, Feyder MJ, Chemmama IE, Fang F, Rout MP, Chait BT, Shi Y, Munson M, Sali A. Integrative structure and function of the yeast exocyst complex. Protein Sci 2020; 29:1486-1501. [PMID: 32239688 DOI: 10.1002/pro.3863] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [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: 03/04/2020] [Revised: 03/25/2020] [Accepted: 03/27/2020] [Indexed: 12/13/2022]
Abstract
Exocyst is an evolutionarily conserved hetero-octameric tethering complex that plays a variety of roles in membrane trafficking, including exocytosis, endocytosis, autophagy, cell polarization, cytokinesis, pathogen invasion, and metastasis. Exocyst serves as a platform for interactions between the Rab, Rho, and Ral small GTPases, SNARE proteins, and Sec1/Munc18 regulators that coordinate spatial and temporal fidelity of membrane fusion. However, its mechanism is poorly described at the molecular level. Here, we determine the molecular architecture of the yeast exocyst complex by an integrative approach, based on a 3D density map from negative-stain electron microscopy (EM) at ~16 Å resolution, 434 disuccinimidyl suberate and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride cross-links from chemical-crosslinking mass spectrometry, and partial atomic models of the eight subunits. The integrative structure is validated by a previously determined cryo-EM structure, cross-links, and distances from in vivo fluorescence microscopy. Our subunit configuration is consistent with the cryo-EM structure, except for Sec5. While not observed in the cryo-EM map, the integrative model localizes the N-terminal half of Sec3 near the Sec6 subunit. Limited proteolysis experiments suggest that the conformation of Exo70 is dynamic, which may have functional implications for SNARE and membrane interactions. This study illustrates how integrative modeling based on varied low-resolution structural data can inform biologically relevant hypotheses, even in the absence of high-resolution data.
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Affiliation(s)
- Sai J Ganesan
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, California, USA.,Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California, USA
| | - Michael J Feyder
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Ilan E Chemmama
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, California, USA.,Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California, USA
| | - Fei Fang
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Michael P Rout
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, New York, USA
| | - Brian T Chait
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, New York, USA
| | - Yi Shi
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Mary Munson
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Andrej Sali
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, California, USA.,Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California, USA
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22
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Nandi SK, Nahomi RB, Rankenberg J, Glomb MA, Nagaraj RH. Glycation-mediated inter- protein cross-linking is promoted by chaperone-client complexes of α-crystallin: Implications for lens aging and presbyopia. J Biol Chem 2020; 295:5701-5716. [PMID: 32184356 PMCID: PMC7186181 DOI: 10.1074/jbc.ra120.012604] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [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: 01/09/2020] [Revised: 03/12/2020] [Indexed: 12/16/2022] Open
Abstract
Lens proteins become increasingly cross-linked through nondisulfide linkages during aging and cataract formation. One mechanism that has been implicated in this cross-linking is glycation through formation of advanced glycation end products (AGEs). Here, we found an age-associated increase in stiffness in human lenses that was directly correlated with levels of protein-cross-linking AGEs. α-Crystallin in the lens binds to other proteins and prevents their denaturation and aggregation through its chaperone-like activity. Using a FRET-based assay, we examined the stability of the αA-crystallin-γD-crystallin complex for up to 12 days and observed that this complex is stable in PBS and upon incubation with human lens-epithelial cell lysate or lens homogenate. Addition of 2 mm ATP to the lysate or homogenate did not decrease the stability of the complex. We also generated complexes of human αA-crystallin or αB-crystallin with alcohol dehydrogenase or citrate synthase by applying thermal stress. Upon glycation under physiological conditions, the chaperone-client complexes underwent greater extents of cross-linking than did uncomplexed protein mixtures. LC-MS/MS analyses revealed that the levels of cross-linking AGEs were significantly higher in the glycated chaperone-client complexes than in glycated but uncomplexed protein mixtures. Mouse lenses subjected to thermal stress followed by glycation lost resilience more extensively than lenses subjected to thermal stress or glycation alone, and this loss was accompanied by higher protein cross-linking and higher cross-linking AGE levels. These results uncover a protein cross-linking mechanism in the lens and suggest that AGE-mediated cross-linking of α-crystallin-client complexes could contribute to lens aging and presbyopia.
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Affiliation(s)
- Sandip K Nandi
- Sue Anschutz-Rodgers Eye Center and Department of Ophthalmology, School of Medicine, University of Colorado, Aurora, Colorado 80045
| | - Rooban B Nahomi
- Sue Anschutz-Rodgers Eye Center and Department of Ophthalmology, School of Medicine, University of Colorado, Aurora, Colorado 80045
| | - Johanna Rankenberg
- Sue Anschutz-Rodgers Eye Center and Department of Ophthalmology, School of Medicine, University of Colorado, Aurora, Colorado 80045
| | - Marcus A Glomb
- Institute of Chemistry-Food Chemistry, Martin-Luther-University Halle-Wittenberg, 06120 Halle/Saale, Germany
| | - Ram H Nagaraj
- Sue Anschutz-Rodgers Eye Center and Department of Ophthalmology, School of Medicine, University of Colorado, Aurora, Colorado 80045; Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Aurora, Colorado 80045.
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23
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Abstract
Structural proteomics refers to large-scale mapping of protein structures in order to understand the relationship between protein sequence, structure, and function. Chemical labeling, in combination with mass-spectrometry (MS) analysis, have emerged as powerful tools to enable a broad range of biological applications in structural proteomics. The key to success is a biocompatible reagent that modifies a protein without affecting its high-order structure. Fluorine, well-known to exert profound effects on the physical and chemical properties of reagents, should have an impact on structural proteomics. In this Minireview, we describe several fluorine-containing reagents that can be applied in structural proteomics. We organize their applications around four MS-based techniques: a) affinity labeling, b) activity-based protein profiling (ABPP), c) protein footprinting, and d) protein cross-linking. Our aim is to provide an overview of the research, development, and application of fluorine-containing reagents in protein structural studies.
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Affiliation(s)
- Ming Cheng
- Department of Chemistry, Washington University in St Louis, St Louis, MO 63130
| | - Chunyang Guo
- Department of Chemistry, Washington University in St Louis, St Louis, MO 63130
| | - Michael L Gross
- Department of Chemistry, Washington University in St Louis, St Louis, MO 63130
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24
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Hannß M, Abbate RA, Mitzenheim E, Alkhalaf M, Böhm W, Lederer A, Henle T. Association of Enzymatically and Nonenzymatically Functionalized Caseins Analyzed by Size-Exclusion Chromatography and Light-Scattering Techniques. J Agric Food Chem 2020; 68:2773-2782. [PMID: 32013417 DOI: 10.1021/acs.jafc.9b06592] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The influence of covalent protein modifications resulting from the Maillard reaction (glycation) of casein and lactose on the noncovalent association behavior of the protein was studied. Nonenzymatic cross-linking with methylglyoxal (MGO) and glutaraldehyde (GTA) as well as enzymatic cross-linking with microbial transglutaminase (mTG) was investigated in comparison. Molar mass, particle size, and conformational characteristics of nonmicellar casein associates as well as the extent of intraparticle protein cross-linking were examined utilizing size-exclusion chromatography (SEC) combined with UV detection and static and dynamic light scattering. Cross-linking resulted in the stabilization of a certain fraction of casein associates, with particle sizes of approximately 30 nm in radius of gyration (Rg), and promoted an incorporation of further casein molecules into those particles, yielding molar masses (Mw) of 1.0-1.2 × 106 g/mol. When caseins were additionally conjugated with lactose during the early Maillard reaction, a further growth of the associates up to approximately 50 nm in Rg with a Mw of 2.1 × 106 g/mol was observed. Furthermore, glycation reactions induced a transition from slightly elongated, random-coil structures toward more anisotropic conformations. Associates consisting of caseins cross-linked with GTA appeared to preserve the original particle conformation.
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Affiliation(s)
- Mariella Hannß
- Chair of Food Chemistry, Technische Universität Dresden, 01062 Dresden, Germany
| | - Raffaele Andrea Abbate
- Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany
- School of Science, Technische Universität Dresden, 01062 Dresden, Germany
| | - Eva Mitzenheim
- Chair of Food Chemistry, Technische Universität Dresden, 01062 Dresden, Germany
| | - Mahmoud Alkhalaf
- Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany
- School of Science, Technische Universität Dresden, 01062 Dresden, Germany
| | - Wendelin Böhm
- Chair of Food Chemistry, Technische Universität Dresden, 01062 Dresden, Germany
| | - Albena Lederer
- Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany
- School of Science, Technische Universität Dresden, 01062 Dresden, Germany
| | - Thomas Henle
- Chair of Food Chemistry, Technische Universität Dresden, 01062 Dresden, Germany
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25
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Abstract
Exposure of biological molecules to oxidants is inevitable and therefore commonplace. Oxidative stress in cells arises from both external agents and endogenous processes that generate reactive species, either purposely (e.g. during pathogen killing or enzymatic reactions) or accidentally (e.g. exposure to radiation, pollutants, drugs, or chemicals). As proteins are highly abundant and react rapidly with many oxidants, they are highly susceptible to, and major targets of, oxidative damage. This can result in changes to protein structure, function, and turnover and to loss or (occasional) gain of activity. Accumulation of oxidatively-modified proteins, due to either increased generation or decreased removal, has been associated with both aging and multiple diseases. Different oxidants generate a broad, and sometimes characteristic, spectrum of post-translational modifications. The kinetics (rates) of damage formation also vary dramatically. There is a pressing need for reliable and robust methods that can detect, identify, and quantify the products formed on amino acids, peptides, and proteins, especially in complex systems. This review summarizes several advances in our understanding of this complex chemistry and highlights methods that are available to detect oxidative modifications-at the amino acid, peptide, or protein level-and their nature, quantity, and position within a peptide sequence. Although considerable progress has been made in the development and application of new techniques, it is clear that further development is required to fully assess the relative importance of protein oxidation and to determine whether an oxidation is a cause, or merely a consequence, of injurious processes.
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Affiliation(s)
- Clare L Hawkins
- Department of Biomedical Sciences, Panum Institute, University of Copenhagen, Copenhagen 2200, Denmark
| | - Michael J Davies
- Department of Biomedical Sciences, Panum Institute, University of Copenhagen, Copenhagen 2200, Denmark
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26
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Jauss B, Petriman NA, Drepper F, Franz L, Sachelaru I, Welte T, Steinberg R, Warscheid B, Koch HG. Noncompetitive binding of PpiD and YidC to the SecYEG translocon expands the global view on the SecYEG interactome in Escherichia coli. J Biol Chem 2019; 294:19167-19183. [PMID: 31699901 DOI: 10.1074/jbc.ra119.010686] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [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: 08/16/2019] [Revised: 10/25/2019] [Indexed: 12/22/2022] Open
Abstract
The SecYEG translocon constitutes the major protein transport channel in bacteria and transfers an enormous variety of different secretory and inner-membrane proteins. The minimal core of the SecYEG translocon consists of three inner-membrane proteins, SecY, SecE, and SecG, which, together with appropriate targeting factors, are sufficient for protein transport in vitro However, in vivo the SecYEG translocon has been shown to associate with multiple partner proteins, likely allowing the SecYEG translocon to process its diverse substrates. To obtain a global view on SecYEG plasticity in Escherichia coli, here we performed a quantitative interaction proteomic analysis, which identified several known SecYEG-interacting proteins, verified the interaction of SecYEG with quality-control proteins, and revealed several previously unknown putative SecYEG-interacting proteins. Surprisingly, we found that the chaperone complex PpiD/YfgM is the most prominent interaction partner of SecYEG. Detailed analyses of the PpiD-SecY interaction by site-directed cross-linking revealed that PpiD and the established SecY partner protein YidC use almost completely-overlapping binding sites on SecY. Both PpiD and YidC contacted the lateral gate, the plug domain, and the periplasmic cavity of SecY. However, quantitative MS and cross-linking analyses revealed that despite having almost identical binding sites, their binding to SecY is noncompetitive. This observation suggests that the SecYEG translocon forms different substrate-independent subassemblies in which SecYEG either associates with YidC or with the PpiD/YfgM complex. In summary, the results of this study indicate that the PpiD/YfgM chaperone complex is a primary interaction partner of the SecYEG translocon.
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Affiliation(s)
- Benjamin Jauss
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Narcis-Adrian Petriman
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany.,Faculty of Biology, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Friedel Drepper
- Faculty of Biology, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany.,Institute of Biology II, Biochemistry and Functional Proteomics, Faculty of Biology, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Lisa Franz
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Ilie Sachelaru
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Thomas Welte
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Ruth Steinberg
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Bettina Warscheid
- Faculty of Biology, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany.,Institute of Biology II, Biochemistry and Functional Proteomics, Faculty of Biology, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Hans-Georg Koch
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
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27
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Irwin MJ, Gupta R, Gao XZ, Cahill KB, Chu F, Cote RH. The molecular architecture of photoreceptor phosphodiesterase 6 (PDE6) with activated G protein elucidates the mechanism of visual excitation. J Biol Chem 2019; 294:19486-19497. [PMID: 31690623 DOI: 10.1074/jbc.ra119.011002] [Citation(s) in RCA: 11] [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: 09/08/2019] [Revised: 10/25/2019] [Indexed: 11/06/2022] Open
Abstract
Photoreceptor phosphodiesterase 6 (PDE6) is the central effector of the visual excitation pathway in both rod and cone photoreceptors, and PDE6 mutations that alter PDE6 structure or regulation can result in several human retinal diseases. The rod PDE6 holoenzyme consists of two catalytic subunits (Pαβ) whose activity is suppressed in the dark by binding of two inhibitory γ-subunits (Pγ). Upon photoactivation of rhodopsin, the heterotrimeric G protein (transducin) is activated, resulting in binding of the activated transducin α-subunit (Gtα) to PDE6, displacement of Pγ from the PDE6 active site, and enzyme activation. Although the biochemistry of this pathway is understood, a lack of detailed structural information about the PDE6 activation mechanism hampers efforts to develop therapeutic interventions for managing PDE6-associated retinal diseases. To address this gap, here we used a cross-linking MS-based approach to create a model of the entire interaction surface of Pγ with the regulatory and catalytic domains of Pαβ in its nonactivated state. Following reconstitution of PDE6 and activated Gtα with liposomes and identification of cross-links between Gtα and PDE6 subunits, we determined that the PDE6-Gtα protein complex consists of two Gtα-binding sites per holoenzyme. Each Gtα interacts with the catalytic domains of both catalytic subunits and induces major changes in the interaction sites of the Pγ subunit with the catalytic subunits. These results provide the first structural model for the activated state of the transducin-PDE6 complex during visual excitation, enhancing our understanding of the molecular etiology of inherited retinal diseases.
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Affiliation(s)
- Michael J Irwin
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, New Hampshire 03824
| | - Richa Gupta
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, New Hampshire 03824
| | - Xiong-Zhuo Gao
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, New Hampshire 03824
| | - Karyn B Cahill
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, New Hampshire 03824
| | - Feixia Chu
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, New Hampshire 03824
| | - Rick H Cote
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, New Hampshire 03824
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28
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Ji S, Park D, Kropachev K, Kolbanovskiy M, Fu I, Broyde S, Essawy M, Geacintov NE, Tretyakova NY. 5-Formylcytosine-induced DNA-peptide cross-links reduce transcription efficiency, but do not cause transcription errors in human cells. J Biol Chem 2019; 294:18387-18397. [PMID: 31597704 DOI: 10.1074/jbc.ra119.009834] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [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: 06/25/2019] [Revised: 09/26/2019] [Indexed: 11/06/2022] Open
Abstract
5-Formylcytosine (5fC) is an endogenous epigenetic DNA mark introduced via enzymatic oxidation of 5-methyl-dC in DNA. We and others recently reported that 5fC can form reversible DNA-protein conjugates with histone proteins, likely contributing to regulation of nucleosomal organization and gene expression. The protein component of DNA-protein cross-links can be proteolytically degraded, resulting in smaller DNA-peptide cross-links. Unlike full-size DNA-protein cross-links that completely block replication and transcription, DNA-peptide cross-links can be bypassed by DNA and RNA polymerases and can potentially be repaired via the nucleotide excision repair (NER) pathway. In the present work, we constructed plasmid molecules containing reductively stabilized, site-specific 5fC-polypeptide lesions and employed a quantitative MS-based assay to assess their effects on transcription in cells. Our results revealed that the presence of DNA-peptide cross-link significantly inhibits transcription in human HEK293T cells but does not induce transcription errors. Furthermore, transcription efficiency was similar in WT and NER-deficient human cell lines, suggesting that the 5fC-polypeptide lesion is a weak substrate for NER. This finding was confirmed by in vitro NER assays in cell-free extracts from human HeLa cells, suggesting that another mechanism is required for 5fC-polypeptide lesion removal. In summary, our findings indicate that 5fC-mediated DNA-peptide cross-links dramatically reduce transcription efficiency, are poor NER substrates, and do not cause transcription errors.
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Affiliation(s)
- Shaofei Ji
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455
| | - Daeyoon Park
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455
| | | | | | - Iwen Fu
- Department of Biology, New York University, New York, New York 10003
| | - Suse Broyde
- Department of Biology, New York University, New York, New York 10003
| | - Maram Essawy
- Department of Pharmacology, University of Minnesota, Minneapolis, Minnesota 55455
| | | | - Natalia Y Tretyakova
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455; Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota 55455.
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29
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Fröbel J, Blümmel AS, Drepper F, Warscheid B, Müller M. Surface-exposed domains of TatB involved in the structural and functional assembly of the Tat translocase in Escherichia coli. J Biol Chem 2019; 294:13902-13914. [PMID: 31341014 DOI: 10.1074/jbc.ra119.009298] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 07/10/2019] [Indexed: 11/06/2022] Open
Abstract
Twin-arginine-dependent translocases transport folded proteins across bacterial, archaeal, and chloroplast membranes. Upon substrate binding, they assemble from hexahelical TatC and single-spanning TatA and TatB membrane proteins. Although structural and functional details of individual Tat subunits have been reported previously, the sequence and dynamics of Tat translocase assembly remain to be determined. Employing the zero-space cross-linker N,N'-dicyclohexylcarbodiimide (DCCD) in combination with LC-MS/MS, we identified as yet unknown intra- and intermolecular contact sites of TatB and TatC. In addition to their established intramembrane binding sites, both proteins were thus found to contact each other through the soluble N terminus of TatC and the interhelical linker region around the conserved glutamyl residue Glu49 of TatB from Escherichia coli Functional analyses suggested that by interacting with the TatC N terminus, TatB improves the formation of a proficient substrate recognition site of TatC. The Glu49 region of TatB was found also to contact distinct downstream sites of a neighboring TatB molecule and to thereby mediate oligomerization of TatB within the TatBC receptor complex. Finally, we show that global DCCD-mediated cross-linking of TatB and TatC in membrane vesicles or, alternatively, creating covalently linked TatC oligomers prevents TatA from occupying a position close to the TatBC-bound substrate. Collectively, our results are consistent with a circular arrangement of the TatB and TatC units within the TatBC receptor complex and with TatA entering the interior TatBC-binding cavity through lateral gates between TatBC protomers.
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Affiliation(s)
- Julia Fröbel
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Anne-Sophie Blümmel
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Friedel Drepper
- Institute of Biology II, Biochemistry-Functional Proteomics, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany.,BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany
| | - Bettina Warscheid
- Institute of Biology II, Biochemistry-Functional Proteomics, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany.,BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany.,CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany
| | - Matthias Müller
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
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30
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Ndi M, Masuyer G, Dawitz H, Carlström A, Michel M, Elofsson A, Rapp M, Stenmark P, Ott M. Structural basis for the interaction of the chaperone Cbp3 with newly synthesized cytochrome b during mitochondrial respiratory chain assembly. J Biol Chem 2019; 294:16663-16671. [PMID: 31537648 DOI: 10.1074/jbc.ra119.010483] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [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: 08/03/2019] [Revised: 09/04/2019] [Indexed: 11/06/2022] Open
Abstract
Assembly of the mitochondrial respiratory chain requires the coordinated synthesis of mitochondrial and nuclear encoded subunits, redox co-factor acquisition, and correct joining of the subunits to form functional complexes. The conserved Cbp3-Cbp6 chaperone complex binds newly synthesized cytochrome b and supports the ordered acquisition of the heme co-factors. Moreover, it functions as a translational activator by interacting with the mitoribosome. Cbp3 consists of two distinct domains: an N-terminal domain present in mitochondrial Cbp3 homologs and a highly conserved C-terminal domain comprising a ubiquinol-cytochrome c chaperone region. Here, we solved the crystal structure of this C-terminal domain from a bacterial homolog at 1.4 Å resolution, revealing a unique all-helical fold. This structure allowed mapping of the interaction sites of yeast Cbp3 with Cbp6 and cytochrome b via site-specific photo-cross-linking. We propose that mitochondrial Cbp3 homologs carry an N-terminal extension that positions the conserved C-terminal domain at the ribosomal tunnel exit for an efficient interaction with its substrate, the newly synthesized cytochrome b protein.
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Affiliation(s)
- Mama Ndi
- Department of Biochemistry and Biophysics, Stockholm University SE-10691 Stockholm, Sweden
| | - Geoffrey Masuyer
- Department of Biochemistry and Biophysics, Stockholm University SE-10691 Stockholm, Sweden.,Department of Pharmacy and Pharmacology, University of Bath, Bath BA2 7AY, United Kingdom
| | - Hannah Dawitz
- Department of Biochemistry and Biophysics, Stockholm University SE-10691 Stockholm, Sweden
| | - Andreas Carlström
- Department of Biochemistry and Biophysics, Stockholm University SE-10691 Stockholm, Sweden
| | - Mirco Michel
- Department of Biochemistry and Biophysics, Stockholm University SE-10691 Stockholm, Sweden.,Science for Life Laboratories, Stockholm University, SE-171 21 Solna, Sweden
| | - Arne Elofsson
- Department of Biochemistry and Biophysics, Stockholm University SE-10691 Stockholm, Sweden.,Science for Life Laboratories, Stockholm University, SE-171 21 Solna, Sweden
| | - Mikaela Rapp
- Department of Biochemistry and Biophysics, Stockholm University SE-10691 Stockholm, Sweden
| | - Pål Stenmark
- Department of Biochemistry and Biophysics, Stockholm University SE-10691 Stockholm, Sweden .,Department of Experimental Medical Science, Lund University, SE-221 84 Lund, Sweden
| | - Martin Ott
- Department of Biochemistry and Biophysics, Stockholm University SE-10691 Stockholm, Sweden
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31
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Ludlam WG, Aoba T, Cuéllar J, Bueno-Carrasco MT, Makaju A, Moody JD, Franklin S, Valpuesta JM, Willardson BM. Molecular architecture of the Bardet-Biedl syndrome protein 2-7-9 subcomplex. J Biol Chem 2019; 294:16385-16399. [PMID: 31530639 DOI: 10.1074/jbc.ra119.010150] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [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: 07/11/2019] [Revised: 09/10/2019] [Indexed: 02/04/2023] Open
Abstract
Bardet-Biedl syndrome (BBS) is a genetic disorder characterized by malfunctions in primary cilia resulting from mutations that disrupt the function of the BBSome, an 8-subunit complex that plays an important role in protein transport in primary cilia. To better understand the molecular basis of BBS, here we used an integrative structural modeling approach consisting of EM and chemical cross-linking coupled with MS analyses, to analyze the structure of a BBSome 2-7-9 subcomplex consisting of three homologous BBS proteins, BBS2, BBS7, and BBS9. The resulting molecular model revealed an overall structure that resembles a flattened triangle. We found that within this structure, BBS2 and BBS7 form a tight dimer through a coiled-coil interaction and that BBS9 associates with the dimer via an interaction with the α-helical domain of BBS2. Interestingly, a BBS-associated mutation of BBS2 (R632P) is located in its α-helical domain at the interface between BBS2 and BBS9, and binding experiments indicated that this mutation disrupts the BBS2-BBS9 interaction. This finding suggests that BBSome assembly is disrupted by the R632P substitution, providing molecular insights that may explain the etiology of BBS in individuals harboring this mutation.
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Affiliation(s)
- W Grant Ludlam
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602
| | - Takuma Aoba
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602
| | - Jorge Cuéllar
- Centro Nacional de Biotecnología (CNB-CSIC), Campus de la Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - M Teresa Bueno-Carrasco
- Centro Nacional de Biotecnología (CNB-CSIC), Campus de la Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Aman Makaju
- Department of Internal Medicine, Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, Utah 84112
| | - James D Moody
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602
| | - Sarah Franklin
- Department of Internal Medicine, Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, Utah 84112
| | - José M Valpuesta
- Centro Nacional de Biotecnología (CNB-CSIC), Campus de la Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Barry M Willardson
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602
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32
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Schmitt LR, Henderson R, Barrett A, Darula Z, Issaian A, D'Alessandro A, Clendenen N, Hansen KC. Mass spectrometry-based molecular mapping of native FXIIIa cross-links in insoluble fibrin clots. J Biol Chem 2019; 294:8773-8778. [PMID: 31028172 DOI: 10.1074/jbc.ac119.007981] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [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: 02/11/2019] [Revised: 04/22/2019] [Indexed: 12/31/2022] Open
Abstract
The roles of factor XIIIa-specific cross-links in thrombus formation, regression, or probability for embolization are largely unknown. A molecular understanding of fibrin architecture at the level of these cross-links could inform the development of therapeutic strategies to prevent the sequelae of thromboembolism. Here, we present an MS-based method to map native factor XIIIa cross-links in the insoluble matrix component of whole-blood or plasma-fibrin clots and in in vivo thrombi. Using a chaotrope-insoluble digestion method and quantitative cross-linking MS, we identified the previously mapped fibrinogen peptides that are responsible for covalent D-dimer association, as well as dozens of novel cross-links in the αC region of fibrinogen α. Our findings expand the known native cross-linked species from one to over 100 and suggest distinct antiparallel registries for interprotofibril association and covalent attachment of serpins that regulate clot dissolution.
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Affiliation(s)
| | - Rachel Henderson
- Anesthesiology, University of Colorado School of Medicine, Aurora, Colorado 80045 and
| | | | - Zsuzsanna Darula
- Laboratory of Proteomics Research, Biological Research Center of the Hungarian Academy of Sciences, H-6701 Szeged, Hungary
| | - Aaron Issaian
- From the Departments of Biochemistry and Molecular Genetics and
| | | | - Nathan Clendenen
- Anesthesiology, University of Colorado School of Medicine, Aurora, Colorado 80045 and
| | - Kirk C Hansen
- From the Departments of Biochemistry and Molecular Genetics and
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Eyre DR, Weis M, Rai J. Analyses of lysine aldehyde cross-linking in collagen reveal that the mature cross-link histidinohydroxylysinonorleucine is an artifact. J Biol Chem 2019; 294:6578-6590. [PMID: 30733334 DOI: 10.1074/jbc.ra118.007202] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [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: 12/26/2018] [Revised: 01/23/2019] [Indexed: 12/30/2022] Open
Abstract
Lysyl oxidase-generated intermolecular cross-links are essential for the tensile strength of collagen fibrils. Two cross-linking pathways can be defined, one based on telopeptide lysine aldehydes and another on telopeptide hydroxylysine aldehydes. Since the 1970s it has been accepted that the mature cross-linking structures on the lysine aldehyde pathway, which dominates in skin and cornea, incorporate histidine residues. Here, using a range of MS-based methods, we re-examined this conclusion and found that telopeptide aldol dimerization is the primary mechanism for stable cross-link formation. The C-telopeptide aldol dimers formed labile addition products with glucosylgalactosyl hydroxylysine at α1(I)K87 in adjacent collagen molecules that resisted borohydride reduction and after acid hydrolysis produced histidinohydroxylysinonorleucine (HHL), but only from species with a histidine in their α1(I) C-telopeptide sequence. Peptide MS analyses and the lack of HHL formation in rat and mouse skin, species that lack an α1(I) C-telopeptide histidine, revealed that HHL is a laboratory artifact rather than a natural cross-linking structure. Our experimental results also establish that histidinohydroxymerodesmosine is produced by borohydride reduction of N-telopeptide allysine aldol dimers in aldimine intermolecular linkage to nonglycosylated α1(I) K930. Borohydride reduction of the aldimine promotes an accompanying base-catalyzed Michael addition of α1(I) H932 imidazole to the α,β-unsaturated aldol. These aldehydes are intramolecular at the N terminus but at the C terminus they can be both intramolecular and intermolecular according to present and earlier findings.
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Affiliation(s)
- David R Eyre
- From the Department of Orthopaedics and Sports Medicine, University of Washington, Seattle, Washington 98195
| | - MaryAnn Weis
- From the Department of Orthopaedics and Sports Medicine, University of Washington, Seattle, Washington 98195
| | - Jyoti Rai
- From the Department of Orthopaedics and Sports Medicine, University of Washington, Seattle, Washington 98195
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Windgassen TA, Leroux M, Sandler SJ, Keck JL. Function of a strand-separation pin element in the PriA DNA replication restart helicase. J Biol Chem 2018; 294:2801-2814. [PMID: 30593500 DOI: 10.1074/jbc.ra118.006870] [Citation(s) in RCA: 16] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 12/26/2018] [Indexed: 11/06/2022] Open
Abstract
DNA helicases are motor proteins that couple the chemical energy of nucleoside triphosphate hydrolysis to the mechanical functions required for DNA unwinding. Studies of several helicases have identified strand-separating "pin" structures that are positioned to intercept incoming dsDNA and promote strand separation during helicase translocation. However, pin structures vary among helicases and it remains unclear whether they confer a conserved unwinding mechanism. Here, we tested the biochemical and cellular roles of a putative pin element within the Escherichia coli PriA DNA helicase. PriA orchestrates replication restart in bacteria by unwinding the lagging-strand arm of abandoned DNA replication forks and reloading the replicative helicase with the help of protein partners that combine with PriA to form what is referred to as a primosome complex. Using in vitro protein-DNA cross-linking, we localized the putative pin (a β-hairpin within a zinc-binding domain in PriA) near the ssDNA-dsDNA junction of the lagging strand in a PriA-DNA replication fork complex. Removal of residues at the tip of the β-hairpin eliminated PriA DNA unwinding, interaction with the primosome protein PriB, and cellular function. We isolated a spontaneous intragenic suppressor mutant of the priA β-hairpin deletion mutant in which 22 codons around the deletion site were duplicated. This suppressor variant and an Ala-substituted β-hairpin PriA variant displayed wildtype levels of DNA unwinding and PriB binding in vitro These results suggest essential but sequence nonspecific roles for the PriA pin element and coupling of PriA DNA unwinding to its interaction with PriB.
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Affiliation(s)
- Tricia A Windgassen
- From the Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53706 and
| | - Maxime Leroux
- the Department of Microbiology, University of Massachusetts, Amherst, Massachusetts 01003
| | - Steven J Sandler
- the Department of Microbiology, University of Massachusetts, Amherst, Massachusetts 01003
| | - James L Keck
- From the Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53706 and
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Buchert F, Hamon M, Gäbelein P, Scholz M, Hippler M, Wollman FA. The labile interactions of cyclic electron flow effector proteins. J Biol Chem 2018; 293:17559-17573. [PMID: 30228184 PMCID: PMC6231120 DOI: 10.1074/jbc.ra118.004475] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [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: 06/14/2018] [Revised: 09/05/2018] [Indexed: 12/16/2022] Open
Abstract
The supramolecular organization of membrane proteins (MPs) is sensitive to environmental changes in photosynthetic organisms. Isolation of MP supercomplexes from the green algae Chlamydomonas reinhardtii, which are believed to contribute to cyclic electron flow (CEF) between the cytochrome b6f complex (Cyt-b6f) and photosystem I (PSI), proved difficult. We were unable to isolate a supercomplex containing both Cyt-b6f and PSI because in our hands, most of Cyt-b6f did not comigrate in sucrose density gradients, even upon using chemical cross-linkers or amphipol substitution of detergents. Assisted by independent affinity purification and MS approaches, we utilized disintegrating MP assemblies and demonstrated that the algae-specific CEF effector proteins PETO and ANR1 are bona fide Cyt-b6f interactors, with ANR1 requiring the presence of an additional, presently unknown, protein. We narrowed down the Cyt-b6f interface, where PETO is loosely attached to cytochrome f and to a stromal region of subunit IV, which also contains phosphorylation sites for the STT7 kinase.
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Affiliation(s)
- Felix Buchert
- From the Institut de Biologie Physico-Chimique, UMR7141 CNRS-Sorbonne-Université, 13 Rue P et M Curie, 75005 Paris, France
- the Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, 48143 Münster, Germany, and
| | - Marion Hamon
- the Institut de Biologie Physico-Chimique, UMR8226/FRC550 CNRS-Sorbonne-Université, 13 Rue P et M Curie, 75005 Paris, France
| | - Philipp Gäbelein
- the Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, 48143 Münster, Germany, and
| | - Martin Scholz
- the Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, 48143 Münster, Germany, and
| | - Michael Hippler
- the Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, 48143 Münster, Germany, and
| | - Francis-André Wollman
- From the Institut de Biologie Physico-Chimique, UMR7141 CNRS-Sorbonne-Université, 13 Rue P et M Curie, 75005 Paris, France,
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36
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Hannß M, Hubbe N, Henle T. Acid-Induced Gelation of Caseins Glycated with Lactose: Impact of Maillard Reaction-Based Glycoconjugation and Protein Cross-Linking. J Agric Food Chem 2018; 66:11477-11485. [PMID: 30295020 DOI: 10.1021/acs.jafc.8b04176] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
During food processing or storage, milk proteins can react with reducing sugars via the Maillard reaction (glycation), which may alter their techno-functional properties. The aim of this study was to investigate the relationship between molecular changes of casein occurring during different stages of the Maillard reaction and its acid-induced gelling properties. Therefore, sodium caseinate was heated in a dry state at 60 °C in the presence of lactose and analyzed for structural modifications by determining Amadori compounds (glycoconjugation) indirectly as furosine, the total lysine modification, and the extent of protein cross-linking. For techno-functional characterization, acid-induced gels were prepared by the addition of glucono-δ-lactone and evaluated by measuring pH kinetics during gel formation, gel strength, and water holding capacity. The time to reach pH 4.6 during the gelation process was significantly delayed with increasing extent of the Maillard reaction. Glycation with lactose also led to a significant increase in gel strength and water holding capacity. The increase in gel stability was rather independent from the amount of sugars covalently bound to the proteins during the early phase of the Maillard reaction but strongly correlated to the degree of protein polymerization. Small- and medium-sized casein oligomers, formed during advanced stages of the Maillard reaction, contributed considerably to the formation of stronger gels with higher water holding capacity, whereas a sharp increase in the relative amount of the polymer fraction observed during prolonged cross-linking processes caused a spontaneous destabilization of the gel network. Knowledge about structure-function relationships on a molecular level can provide useful information to control food texture by raw material quality.
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Affiliation(s)
- Mariella Hannß
- Chair of Food Chemistry , Technische Universität Dresden , 01062 Dresden , Germany
| | - Natalie Hubbe
- Chair of Food Chemistry , Technische Universität Dresden , 01062 Dresden , Germany
| | - Thomas Henle
- Chair of Food Chemistry , Technische Universität Dresden , 01062 Dresden , Germany
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37
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Belyy A, Santecchia I, Renault L, Bourigault B, Ladant D, Mechold U. The extreme C terminus of the Pseudomonas aeruginosa effector ExoY is crucial for binding to its eukaryotic activator, F-actin. J Biol Chem 2018; 293:19785-19796. [PMID: 30377256 DOI: 10.1074/jbc.ra118.003784] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [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: 05/26/2018] [Revised: 10/22/2018] [Indexed: 12/25/2022] Open
Abstract
Bacterial nucleotidyl cyclase toxins are potent virulence factors that upon entry into eukaryotic cells are stimulated by endogenous cofactors to catalyze the production of large amounts of 3'5'-cyclic nucleoside monophosphates. The activity of the effector ExoY from Pseudomonas aeruginosa is stimulated by the filamentous form of actin (F-actin). Utilizing yeast phenotype analysis, site-directed mutagenesis, functional biochemical assays, and confocal microscopy, we demonstrate that the last nine amino acids of the C terminus of ExoY are crucial for the interaction with F-actin and, consequently, for ExoY's enzymatic activity in vitro and toxicity in a yeast model. We observed that isolated C-terminal sequences of P. aeruginosa ExoY that had been fused to a carrier protein bind to F-actin and that synthetic peptides corresponding to the extreme ExoY C terminus inhibit ExoY enzymatic activity in vitro and compete with the full-length enzyme for F-actin binding. Interestingly, we noted that various P. aeruginosa isolates of the PA14 family, including highly virulent strains, harbor ExoY variants with a mutation altering the C terminus of this effector. We found that these naturally occurring ExoY variants display drastically reduced enzymatic activity and toxicity. Our findings shed light on the molecular basis of the ExoY-F-actin interaction, revealing that the extreme C terminus of ExoY is critical for binding to F-actin in target cells and that some P. aeruginosa isolates carry C-terminally mutated, low-activity ExoY variants.
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Affiliation(s)
- Alexander Belyy
- From the Institut Pasteur, CNRS UMR 3528, Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie and
| | - Ignacio Santecchia
- Unité Biologie et Génétique de la Paroi Bactérienne, Département de Microbiologie, 75724 Paris cedex 15, France and
| | - Louis Renault
- the Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198, Gif-sur-Yvette cedex, France
| | - Blandine Bourigault
- the Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198, Gif-sur-Yvette cedex, France
| | - Daniel Ladant
- From the Institut Pasteur, CNRS UMR 3528, Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie and
| | - Undine Mechold
- From the Institut Pasteur, CNRS UMR 3528, Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie and
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38
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George MN, Pedigo B, Carrington E. Hypoxia weakens mussel attachment by interrupting DOPA cross-linking during adhesive plaque curing. J R Soc Interface 2018; 15:20180489. [PMID: 30355807 PMCID: PMC6228490 DOI: 10.1098/rsif.2018.0489] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [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: 06/29/2018] [Accepted: 09/25/2018] [Indexed: 12/12/2022] Open
Abstract
Marine mussels (Mytilus spp.) attach to a wide variety of surfaces underwater using a network of byssal threads, each tipped with a protein-based adhesive plaque that uses the surrounding seawater environment as a curing agent. Plaques undergo environmental post-processing, requiring a basic seawater pH be maintained for up to 8 days for the adhesive to strengthen completely. Given the sensitivity of plaques to local pH conditions long after deposition, we investigated the effect of other aspects of the seawater environment that are known to vary in nearshore habitats on plaque curing. The effect of seawater temperature, salinity and dissolved oxygen concentration were investigated using tensile testing, atomic force microscopy and amino acid compositional analysis. High temperature (30°C) and hyposalinity (1 PSU) had no effect on adhesion strength, while incubation in hypoxia (0.9 mg l-1) caused plaques to have a mottled coloration and prematurely peel from substrates, leading to a 51% decrease in adhesion strength. AFM imaging of the plaque cuticle found that plaques cured in hypoxia had regions of lower stiffness throughout, indicative of reductions in DOPA cross-linking between adhesive proteins. A better understanding of the dynamics of plaque curing could aid in the design of better synthetic adhesives, particularly in medicine where adhesion must take place within wet body cavities.
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Affiliation(s)
- Matthew N George
- Friday Harbor Laboratories, 620 University Road, Friday Harbor, WA 98250, USA
- Department of Biology, University of Washington, 24 Kincaid Hall, Seattle, WA 98195, USA
| | - Benjamin Pedigo
- Department of Bioengineering, University of Washington, 720 15th Avenue NE, Seattle, WA 98105, USA
| | - Emily Carrington
- Friday Harbor Laboratories, 620 University Road, Friday Harbor, WA 98250, USA
- Department of Biology, University of Washington, 24 Kincaid Hall, Seattle, WA 98195, USA
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Sugita S, Watanabe K, Hashimoto K, Niwa T, Uemura E, Taguchi H, Watanabe YH. Electrostatic interactions between middle domain motif-1 and the AAA1 module of the bacterial ClpB chaperone are essential for protein disaggregation. J Biol Chem 2018; 293:19228-19239. [PMID: 30327424 DOI: 10.1074/jbc.ra118.005496] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [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: 08/22/2018] [Revised: 10/11/2018] [Indexed: 11/06/2022] Open
Abstract
ClpB, a bacterial homologue of heat shock protein 104 (Hsp104), can disentangle aggregated proteins with the help of the DnaK, a bacterial Hsp70, and its co-factors. As a member of the expanded superfamily of ATPases associated with diverse cellular activities (AAA+), ClpB forms a hexameric ring structure, with each protomer containing two AAA+ modules, AAA1 and AAA2. A long coiled-coil middle domain (MD) is present in the C-terminal region of the AAA1 and surrounds the main body of the ring. The MD is subdivided into two oppositely directed short coiled-coils, called motif-1 and motif-2. The MD represses the ATPase activity of ClpB, and this repression is reversed by the binding of DnaK to motif-2. To better understand how the MD regulates ClpB activity, here we investigated the roles of motif-1 in ClpB from Thermus thermophilus (TClpB). Using systematic alanine substitution of the conserved charged residues, we identified functionally important residues in motif-1, and using a photoreactive cross-linker and LC-MS/MS analysis, we further explored potential interacting residues. Moreover, we constructed TClpB mutants in which functionally important residues in motif-1 and in other candidate regions were substituted by oppositely charged residues. These analyses revealed that the intra-subunit pair Glu-401-Arg-532 and the inter-subunit pair Asp-404-Arg-180 are functionally important, electrostatically interacting pairs. Considering these structural findings, we conclude that the Glu-401-Arg-532 interaction shifts the equilibrium of the MD conformation to stabilize the activated form and that the Arg-180-Asp-404 interaction contributes to intersubunit signal transduction, essential for ClpB chaperone activities.
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Affiliation(s)
- Saori Sugita
- From the Department of Biology, Faculty of Science and Engineering and
| | - Kumiko Watanabe
- From the Department of Biology, Faculty of Science and Engineering and
| | - Kana Hashimoto
- From the Department of Biology, Faculty of Science and Engineering and
| | - Tatsuya Niwa
- the Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8503, Japan
| | - Eri Uemura
- the Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8503, Japan
| | - Hideki Taguchi
- the Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8503, Japan
| | - Yo-Hei Watanabe
- From the Department of Biology, Faculty of Science and Engineering and .,Institute for Integrative Neurobiology, Konan University, Okamoto 8-9-1, Kobe 658-8501 and
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40
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Nguyen TT, Sabat G, Sussman MR. In vivo cross-linking supports a head-to-tail mechanism for regulation of the plant plasma membrane P-type H +-ATPase. J Biol Chem 2018; 293:17095-17106. [PMID: 30217814 DOI: 10.1074/jbc.ra118.003528] [Citation(s) in RCA: 13] [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: 04/18/2018] [Revised: 08/30/2018] [Indexed: 11/06/2022] Open
Abstract
In higher plants, a P-type proton-pumping ATPase generates the proton-motive force essential for the function of all other transporters and for proper growth and development. X-ray crystallographic studies of the plant plasma membrane proton pump have provided information on amino acids involved in ATP catalysis but provided no information on the structure of the C-terminal regulatory domain. Despite progress in elucidating enzymes involved in the signaling pathways that activate or inhibit this pump, the site of interaction of the C-terminal regulatory domain with the catalytic domains remains a mystery. Genetic studies have pointed to amino acids in various parts of the protein that may be involved, but direct chemical evidence for which ones are specifically interacting with the C terminus is lacking. In this study, we used in vivo cross-linking experiments with a photoreactive unnatural amino acid, p-benzoylphenylalanine, and tandem MS to obtain direct evidence that the C-terminal regulatory domain interacts with amino acids located within the N-terminal actuator domain. Our observations are consistent with a mechanism in which intermolecular, rather than intramolecular, interactions are involved. Our model invokes a "head-to-tail" organization of ATPase monomers in which the C-terminal domain of one ATPase molecule interacts with the actuator domain of another ATPase molecule. This model serves to explain why cross-linked peptides are found only in dimers and trimers, and it is consistent with prior studies suggesting that within the membrane the protein can be organized as homopolymers, including dimers, trimers, and hexamers.
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Affiliation(s)
- Thao T Nguyen
- From the Biotechnology Center and.,Biochemistry Department, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | | | - Michael R Sussman
- From the Biotechnology Center and .,Biochemistry Department, University of Wisconsin-Madison, Madison, Wisconsin 53706
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Schräder CU, Heinz A, Majovsky P, Karaman Mayack B, Brinckmann J, Sippl W, Schmelzer CEH. Elastin is heterogeneously cross-linked. J Biol Chem 2018; 293:15107-15119. [PMID: 30108173 DOI: 10.1074/jbc.ra118.004322] [Citation(s) in RCA: 36] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 08/12/2018] [Indexed: 01/30/2023] Open
Abstract
Elastin is an essential vertebrate protein responsible for the elasticity of force-bearing tissues such as those of the lungs, blood vessels, and skin. One of the key features required for the exceptional properties of this durable biopolymer is the extensive covalent cross-linking between domains of its monomer molecule tropoelastin. To date, elastin's exact molecular assembly and mechanical properties are poorly understood. Here, using bovine elastin, we investigated the different types of cross-links in mature elastin to gain insight into its structure. We purified and proteolytically cleaved elastin from a single tissue sample into soluble cross-linked and noncross-linked peptides that we studied by high-resolution MS. This analysis enabled the elucidation of cross-links and other elastin modifications. We found that the lysine residues within the tropoelastin sequence were simultaneously unmodified and involved in various types of cross-links with different other domains. The Lys-Pro domains were almost exclusively linked via lysinonorleucine, whereas Lys-Ala domains were found to be cross-linked via lysinonorleucine, allysine aldol, and desmosine. Unexpectedly, we identified a high number of intramolecular cross-links between lysine residues in close proximity. In summary, we show on the molecular level that elastin formation involves random cross-linking of tropoelastin monomers resulting in an unordered network, an unexpected finding compared with previous assumptions of an overall beaded structure.
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Affiliation(s)
- Christoph U Schräder
- From the Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Halle (Saale) 06120, Germany
| | - Andrea Heinz
- From the Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Halle (Saale) 06120, Germany.,the Department of Pharmacy, University of Copenhagen, Copenhagen 2100, Denmark
| | - Petra Majovsky
- the Proteome Analytics Research Group, Leibniz Institute for Plant Biochemistry, Halle (Saale) 06120, Germany
| | - Berin Karaman Mayack
- From the Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Halle (Saale) 06120, Germany
| | - Jürgen Brinckmann
- the Institute of Virology and Cell Biology, Department of Dermatology, University of Lübeck, Lübeck 23538, Germany, and
| | - Wolfgang Sippl
- From the Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Halle (Saale) 06120, Germany
| | - Christian E H Schmelzer
- From the Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Halle (Saale) 06120, Germany, .,the Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Halle (Saale) 06120, Germany
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42
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Tarasuntisuk S, Patipong T, Hibino T, Waditee-Sirisattha R, Kageyama H. Inhibitory effects of mycosporine-2-glycine isolated from a halotolerant cyanobacterium on protein glycation and collagenase activity. Lett Appl Microbiol 2018; 67:314-320. [PMID: 29947423 DOI: 10.1111/lam.13041] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [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: 02/25/2018] [Revised: 06/14/2018] [Accepted: 06/25/2018] [Indexed: 01/07/2023]
Abstract
Mycosporine-2-glycine (M2G), isolated from the halotolerant cyanobacterium Aphanothece halophytica, was purified and characterized in order to determine its utility as a cosmetic and pharmaceutical ingredient. M2G efficiently inhibited protein crosslinking. The inhibitory activity of M2G was significantly greater than that of the well-known Maillard reaction inhibitor aminoguanidine. In addition, M2G and other known mycosporine-like amino acids inhibited bacterial collagenase activity. To the best of our knowledge, this is the first report describing that M2G specifically inhibits the formation of advanced glycation end-products (AGEs), which play a critical role in ageing process and age-related diseases. These observations indicate that M2G may have potential therapeutic applications by suppressing the formation of AGEs and inhibiting excess collagenase activity. SIGNIFICANCE AND IMPACT OF THE STUDY Mycosporine-like amino acids (MAAs) are known as multifunctional natural compounds. The MAA mycosporine-2-glycine (M2G), isolated from the halotolerant cyanobacterium Aphanothece halophytica, has potential therapeutic applications for the prevention of skin ageing. Purified M2G was endotoxin-free. M2G had greater inhibitory activity of protein cross-linking compared with well-known inhibitor, aminoguanidine and hindered bacterial collagenase activity. The mechanisms for these inhibitory activities of M2G are discussed in this study.
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Affiliation(s)
- S Tarasuntisuk
- Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | - T Patipong
- Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | - T Hibino
- Graduate School of Environmental and Human Sciences, Meijo University, Nagoya, Japan
| | - R Waditee-Sirisattha
- Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | - H Kageyama
- Graduate School of Environmental and Human Sciences, Meijo University, Nagoya, Japan
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43
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Martin EM, Jackson MP, Gamerdinger M, Gense K, Karamonos TK, Humes JR, Deuerling E, Ashcroft AE, Radford SE. Conformational flexibility within the nascent polypeptide-associated complex enables its interactions with structurally diverse client proteins. J Biol Chem 2018; 293:8554-8568. [PMID: 29650757 PMCID: PMC5986199 DOI: 10.1074/jbc.ra117.001568] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 04/07/2018] [Indexed: 12/12/2022] Open
Abstract
As newly synthesized polypeptides emerge from the ribosome, it is crucial that they fold correctly. To prevent premature aggregation, nascent chains interact with chaperones that facilitate folding or prevent misfolding until protein synthesis is complete. Nascent polypeptide-associated complex (NAC) is a ribosome-associated chaperone that is important for protein homeostasis. However, how NAC binds its substrates remains unclear. Using native electrospray ionization MS (ESI-MS), limited proteolysis, NMR, and cross-linking, we analyzed the conformational properties of NAC from Caenorhabditis elegans and studied its ability to bind proteins in different conformational states. Our results revealed that NAC adopts an array of compact and expanded conformations and binds weakly to client proteins that are unfolded, folded, or intrinsically disordered, suggestive of broad substrate compatibility. Of note, we found that this weak binding retards aggregation of the intrinsically disordered protein α-synuclein both in vitro and in vivo These findings provide critical insights into the structure and function of NAC. Specifically, they reveal the ability of NAC to exploit its conformational plasticity to bind a repertoire of substrates with unrelated sequences and structures, independently of actively translating ribosomes.
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Affiliation(s)
- Esther M Martin
- From the Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom and
| | - Matthew P Jackson
- From the Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom and
| | - Martin Gamerdinger
- the Department of Biology, Institute of Molecular Microbiology, University of Konstanz, 78454 Konstanz, Germany
| | - Karina Gense
- the Department of Biology, Institute of Molecular Microbiology, University of Konstanz, 78454 Konstanz, Germany
| | - Theodoros K Karamonos
- From the Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom and
| | - Julia R Humes
- From the Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom and
| | - Elke Deuerling
- the Department of Biology, Institute of Molecular Microbiology, University of Konstanz, 78454 Konstanz, Germany
| | - Alison E Ashcroft
- From the Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom and
| | - Sheena E Radford
- From the Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom and
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44
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Willis WL, Wang L, Wada TT, Gardner M, Abdouni O, Hampton J, Valiente G, Young N, Ardoin S, Agarwal S, Freitas MA, Wu LC, Jarjour WN. The proinflammatory protein HMGB1 is a substrate of transglutaminase-2 and forms high-molecular weight complexes with autoantigens. J Biol Chem 2018; 293:8394-8409. [PMID: 29618516 DOI: 10.1074/jbc.ra117.001078] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [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: 11/21/2017] [Revised: 03/27/2018] [Indexed: 12/26/2022] Open
Abstract
High-mobility group box 1 (HMGB1) is a chromatin-associated protein that, in response to stress or injury, translocates from the nucleus to the extracellular milieu, where it functions as an alarmin. HMGB1's function is in part determined by the complexes (HMGB1c) it forms with other molecules. However, structural modifications in the HMGB1 polypeptide that may regulate HMGB1c formation have not been previously described. In this report, we observed high-molecular weight, denaturing-resistant HMGB1c in the plasma and peripheral blood mononuclear cells of individuals with systemic lupus erythematosus (SLE) and, to a much lesser extent, in healthy subjects. Differential HMGB1c levels were also detected in mouse tissues and cultured cells, in which these complexes were induced by endotoxin or the immunological adjuvant alum. Of note, we found that HMGB1c formation is catalyzed by the protein-cross-linking enzyme transglutaminase-2 (TG2). Cross-link site mapping and MS analysis revealed that HMGB1 can be cross-linked to TG2 as well as a number of additional proteins, including human autoantigens. These findings have significant functional implications for studies of cellular stress responses and innate immunity in SLE and other autoimmune disease.
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Affiliation(s)
- William L Willis
- From the Departments of Internal Medicine, .,The Ohio State University Wexner Medical Center, Columbus, Ohio 43210
| | - Linan Wang
- The Ohio State University Wexner Medical Center, Columbus, Ohio 43210.,Cancer Biology and Genetics, and
| | - Takuma Tsuzuki Wada
- From the Departments of Internal Medicine.,The Ohio State University Wexner Medical Center, Columbus, Ohio 43210
| | - Mark Gardner
- From the Departments of Internal Medicine.,The Ohio State University Wexner Medical Center, Columbus, Ohio 43210
| | - Omar Abdouni
- From the Departments of Internal Medicine.,The Ohio State University Wexner Medical Center, Columbus, Ohio 43210
| | - Jeffrey Hampton
- From the Departments of Internal Medicine.,The Ohio State University Wexner Medical Center, Columbus, Ohio 43210
| | - Giancarlo Valiente
- From the Departments of Internal Medicine.,The Ohio State University Wexner Medical Center, Columbus, Ohio 43210
| | - Nicholas Young
- From the Departments of Internal Medicine.,The Ohio State University Wexner Medical Center, Columbus, Ohio 43210
| | - Stacy Ardoin
- From the Departments of Internal Medicine.,The Ohio State University Wexner Medical Center, Columbus, Ohio 43210
| | - Sudha Agarwal
- Division of Biosciences, The Ohio State University College of Dentistry, Columbus, Ohio 43210.,the Department of Orthopedics, The Ohio State University College of Medicine, Columbus, Ohio 43210, and
| | - Michael A Freitas
- The Ohio State University Wexner Medical Center, Columbus, Ohio 43210.,Cancer Biology and Genetics, and
| | - Lai-Chu Wu
- From the Departments of Internal Medicine.,Biological Chemistry and Pharmacology and
| | - Wael N Jarjour
- From the Departments of Internal Medicine, .,The Ohio State University Wexner Medical Center, Columbus, Ohio 43210
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45
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Ramezanpour M, Lee J, Taneva SG, Tieleman DP, Cornell RB. An auto-inhibitory helix in CTP:phosphocholine cytidylyltransferase hijacks the catalytic residue and constrains a pliable, domain-bridging helix pair. J Biol Chem 2018. [PMID: 29519816 DOI: 10.1074/jbc.ra118.002053] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [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: 11/06/2022] Open
Abstract
The activity of CTP:phosphocholine cytidylyltransferase (CCT), a key enzyme in phosphatidylcholine synthesis, is regulated by reversible interactions of a lipid-inducible amphipathic helix (domain M) with membrane phospholipids. When dissociated from membranes, a portion of the M domain functions as an auto-inhibitory (AI) element to suppress catalysis. The AI helix from each subunit binds to a pair of α helices (αE) that extend from the base of the catalytic dimer to create a four-helix bundle. The bound AI helices make intimate contact with loop L2, housing a key catalytic residue, Lys122 The impacts of the AI helix on active-site dynamics and positioning of Lys122 are unknown. Extensive MD simulations with and without the AI helix revealed that backbone carbonyl oxygens at the point of contact between the AI helix and loop L2 can entrap the Lys122 side chain, effectively competing with the substrate, CTP. In silico, removal of the AI helices dramatically increased αE dynamics at a predicted break in the middle of these helices, enabling them to splay apart and forge new contacts with loop L2. In vitro cross-linking confirmed the reorganization of the αE element upon membrane binding of the AI helix. Moreover, when αE bending was prevented by disulfide engineering, CCT activation by membrane binding was thwarted. These findings suggest a novel two-part auto-inhibitory mechanism for CCT involving capture of Lys122 and restraint of the pliable αE helices. We propose that membrane binding enables bending of the αE helices, bringing the active site closer to the membrane surface.
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Affiliation(s)
- Mohsen Ramezanpour
- From the Centre for Molecular Simulation, Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4 and
| | - Jaeyong Lee
- the Departments of Molecular Biology and Biochemistry and
| | | | - D Peter Tieleman
- From the Centre for Molecular Simulation, Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4 and
| | - Rosemary B Cornell
- the Departments of Molecular Biology and Biochemistry and .,Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
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46
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Dickmanns A, Zschiedrich CP, Arens J, Parfentev I, Gundlach J, Hofele R, Neumann P, Urlaub H, Görke B, Ficner R, Stülke J. Structural basis for the regulatory interaction of the methylglyoxal synthase MgsA with the carbon flux regulator Crh in Bacillus subtilis. J Biol Chem 2018. [PMID: 29514981 DOI: 10.1074/jbc.ra117.001289] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [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: 01/17/2023] Open
Abstract
Utilization of energy-rich carbon sources such as glucose is fundamental to the evolutionary success of bacteria. Glucose can be catabolized via glycolysis for feeding the intermediary metabolism. The methylglyoxal synthase MgsA produces methylglyoxal from the glycolytic intermediate dihydroxyacetone phosphate. Methylglyoxal is toxic, requiring stringent regulation of MgsA activity. In the Gram-positive bacterium Bacillus subtilis, an interaction with the phosphoprotein Crh controls MgsA activity. In the absence of preferred carbon sources, Crh is present in the nonphosphorylated state and binds to and thereby inhibits MgsA. To better understand the mechanism of regulation of MgsA, here we performed biochemical and structural analyses of B. subtilis MgsA and of its interaction with Crh. Our results indicated that MgsA forms a hexamer (i.e. a trimer of dimers) in the crystal structure, whereas it seems to exist in an equilibrium between a dimer and hexamer in solution. In the hexamer, two alternative dimers could be distinguished, but only one appeared to prevail in solution. Further analysis strongly suggested that the hexamer is the biologically active form. In vitro cross-linking studies revealed that Crh interacts with the N-terminal helices of MgsA and that the Crh-MgsA binding inactivates MgsA by distorting and thereby blocking its active site. In summary, our results indicate that dimeric and hexameric MgsA species exist in an equilibrium in solution, that the hexameric species is the active form, and that binding to Crh deforms and blocks the active site in MgsA.
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Affiliation(s)
| | | | - Johannes Arens
- From the Departments of Molecular Structural Biology and
| | - Iwan Parfentev
- the Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany, and.,the Bioanalytics Group, Institute for Clinical Chemistry, University Medical Center Göttingen, 37075 Göttingen, Germany
| | - Jan Gundlach
- General Microbiology, GZMB, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Romina Hofele
- the Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany, and.,the Bioanalytics Group, Institute for Clinical Chemistry, University Medical Center Göttingen, 37075 Göttingen, Germany
| | - Piotr Neumann
- From the Departments of Molecular Structural Biology and
| | - Henning Urlaub
- the Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany, and.,the Bioanalytics Group, Institute for Clinical Chemistry, University Medical Center Göttingen, 37075 Göttingen, Germany
| | - Boris Görke
- General Microbiology, GZMB, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Ralf Ficner
- From the Departments of Molecular Structural Biology and
| | - Jörg Stülke
- General Microbiology, GZMB, Georg-August-University Göttingen, 37077 Göttingen, Germany,
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47
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Blümmel AS, Drepper F, Knapp B, Eimer E, Warscheid B, Müller M, Fröbel J. Structural features of the TatC membrane protein that determine docking and insertion of a twin-arginine signal peptide. J Biol Chem 2017; 292:21320-21329. [PMID: 29089385 DOI: 10.1074/jbc.m117.812560] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [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: 08/16/2017] [Revised: 10/26/2017] [Indexed: 11/06/2022] Open
Abstract
Twin-arginine translocation (Tat) systems transport folded proteins across cellular membranes with the concerted action of mostly three membrane proteins: TatA, TatB, and TatC. Hetero-oligomers of TatB and TatC form circular substrate-receptor complexes with a central binding cavity for twin-arginine-containing signal peptides. After binding of the substrate, energy from an electro-chemical proton gradient is transduced into the recruitment of TatA oligomers and into the actual translocation event. We previously reported that Tat-dependent protein translocation into membrane vesicles of Escherichia coli is blocked by the compound N,N'-dicyclohexylcarbodiimide (DCCD, DCC). We have now identified a highly conserved glutamate residue in the transmembrane region of E. coli TatC, which when modified by DCCD interferes with the deep insertion of a Tat signal peptide into the TatBC receptor complex. Our findings are consistent with a hydrophobic binding cavity formed by TatB and TatC inside the lipid bilayer. Moreover, we found that DCCD mediates discrete intramolecular cross-links of E. coli TatC involving both its N- and C-tails. These results confirm the close proximity of two distant sequence sections of TatC proposed to concertedly function as the primary docking site for twin-arginine signal peptides.
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Affiliation(s)
- Anne-Sophie Blümmel
- From the Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine.,the Spemann Graduate School of Biology and Medicine (SGBM).,the Faculty of Biology
| | - Friedel Drepper
- the Institute of Biology II, Biochemistry: Functional Proteomics, Faculty of Biology, and.,the BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany
| | - Bettina Knapp
- the Institute of Biology II, Biochemistry: Functional Proteomics, Faculty of Biology, and
| | - Ekaterina Eimer
- From the Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine.,the Faculty of Biology
| | - Bettina Warscheid
- the Institute of Biology II, Biochemistry: Functional Proteomics, Faculty of Biology, and.,the BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany
| | - Matthias Müller
- From the Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine,
| | - Julia Fröbel
- From the Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine
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48
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Zaidi H, Hoffman EA, Shetty SJ, Bekiranov S, Auble DT. Second-generation method for analysis of chromatin binding with formaldehyde-cross-linking kinetics. J Biol Chem 2017; 292:19338-19355. [PMID: 28972159 DOI: 10.1074/jbc.m117.796441] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 09/21/2017] [Indexed: 11/06/2022] Open
Abstract
Formaldehyde-cross-linking underpins many of the most commonly used experimental approaches in the chromatin field, especially in capturing site-specific protein-DNA interactions. Extending such assays to assess the stability and binding kinetics of protein-DNA interactions is more challenging, requiring absolute measurements with a relatively high degree of physical precision. We previously described an experimental framework called the cross-linking kinetics (CLK) assay, which uses time-dependent formaldehyde-cross-linking data to extract kinetic parameters of chromatin binding. Many aspects of formaldehyde behavior in cells are unknown or undocumented, however, and could potentially affect CLK data analyses. Here, we report biochemical results that better define the properties of formaldehyde-cross-linking in budding yeast cells. These results have the potential to inform interpretations of "standard" chromatin assays, including chromatin immunoprecipitation. Moreover, the chemical complexity we uncovered resulted in the development of an improved method for measuring binding kinetics with the CLK approach. Optimum conditions included an increased formaldehyde concentration and more robust glycine-quench conditions. Notably, we observed that formaldehyde-cross-linking rates can vary dramatically for different protein-DNA interactions in vivo Some interactions were cross-linked much faster than the in vivo macromolecular interactions, making them suitable for kinetic analysis. For other interactions, we found the cross-linking reaction occurred on the same time scale or slower than binding dynamics; for these interactions, it was sometimes possible to compute the in vivo equilibrium-binding constant but not binding on- and off-rates. This improved method yields more accurate in vivo binding kinetics estimates on the minute time scale.
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Affiliation(s)
- Hussain Zaidi
- From the School of Medicine Research Computing, University of Virginia and
| | - Elizabeth A Hoffman
- the Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, Virginia 22908
| | - Savera J Shetty
- the Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, Virginia 22908
| | - Stefan Bekiranov
- the Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, Virginia 22908
| | - David T Auble
- the Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, Virginia 22908
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49
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Yao P, Sun H, Xu C, Chen T, Zou B, Jiang P, Du W. Evidence for a direct cross-talk between malic enzyme and the pentose phosphate pathway via structural interactions. J Biol Chem 2017; 292:17113-17120. [PMID: 28848047 DOI: 10.1074/jbc.m117.810309] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 08/24/2017] [Indexed: 11/06/2022] Open
Abstract
Recent studies have revealed that the oxidative pentose phosphate pathway (PPP), malic enzyme (ME), and folate metabolism are the three major routes for generating cellular NADPH, a key cofactor involved in redox control and reductive biosynthesis. Many tumor cells exhibit altered NADPH metabolism to fuel their rapid proliferation. However, little is known about how NADPH metabolism is coordinated in tumor cells. Here we report that ME1 increases the PPP flux by forming physiological complexes with 6-phosphogluconate dehydrogenase (6PGD). We found that ME1 and 6PGD form a hetero-oligomer that increases the capability of 6PGD to bind its substrate 6-phosphogluconate. Through activating 6PGD, ME1 enhances NADPH generation, PPP flux, and tumor cell growth. Interestingly, although ME1 could bind either the dimer-defect mutant 6PGD (K294R) or the NADP+-binding defect 6PGD mutants, only 6PGD (K294R) activity was induced by ME1. Thus, ME1/6PGD hetero-complexes may mimic the active oligomer form of 6PGD. Together, these findings uncover a direct cross-talk mechanism between ME1 and PPP, may reveal an alternative model for signaling transduction via protein conformational simulation, and pave the way for better understanding how metabolic pathways are coordinated in cancer.
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Affiliation(s)
- Pengbo Yao
- From the School of Life Sciences, Tsinghua University, Beijing 100084, China and
| | - Huishan Sun
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences and School of Basic Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China
| | - Chang Xu
- From the School of Life Sciences, Tsinghua University, Beijing 100084, China and
| | - Taiqi Chen
- From the School of Life Sciences, Tsinghua University, Beijing 100084, China and
| | - Bing Zou
- From the School of Life Sciences, Tsinghua University, Beijing 100084, China and
| | - Peng Jiang
- From the School of Life Sciences, Tsinghua University, Beijing 100084, China and
| | - Wenjing Du
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences and School of Basic Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China
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50
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Wang X, Chemmama IE, Yu C, Huszagh A, Xu Y, Viner R, Block SA, Cimermancic P, Rychnovsky SD, Ye Y, Sali A, Huang L. The proteasome-interacting Ecm29 protein disassembles the 26S proteasome in response to oxidative stress. J Biol Chem 2017; 292:16310-16320. [PMID: 28821611 DOI: 10.1074/jbc.m117.803619] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [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: 06/22/2017] [Revised: 08/11/2017] [Indexed: 01/17/2023] Open
Abstract
Oxidative stress has been implicated in multiple human neurological and other disorders. Proteasomes are multi-subunit proteases critical for the removal of oxidatively damaged proteins. To understand stress-associated human pathologies, it is important to uncover the molecular events underlying the regulation of proteasomes upon oxidative stress. To this end, we investigated H2O2 stress-induced molecular changes of the human 26S proteasome and determined that stress-induced 26S proteasome disassembly is conserved from yeast to human. Moreover, we developed and employed a new proteomic approach, XAP (in vivo cross-linking-assisted affinity purification), coupled with stable isotope labeling with amino acids in cell culture (SILAC)-based quantitative MS, to capture and quantify several weakly bound proteasome-interacting proteins and examine their roles in stress-mediated proteasomal remodeling. Our results indicate that the adapter protein Ecm29 is the main proteasome-interacting protein responsible for stress-triggered remodeling of the 26S proteasome in human cells. Importantly, using a disuccinimidyl sulfoxide-based cross-linking MS platform, we mapped the interactions of Ecm29 within itself and with proteasome subunits and determined the architecture of the Ecm29-proteasome complex with integrative structure modeling. These results enabled us to propose a structural model in which Ecm29 intrudes on the interaction between the 20S core particle and the 19S regulatory particle in the 26S proteasome, disrupting the proteasome structure in response to oxidative stress.
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Affiliation(s)
- Xiaorong Wang
- From the Department of Physiology and Biophysics, University of California, Irvine, California 92697
| | - Ilan E Chemmama
- the Departments of Bioengineering and Therapeutic Sciences and Pharmaceutical Chemistry, California Institute for Quantitative Biosciences, University of California, San Francisco, California 94143
| | - Clinton Yu
- From the Department of Physiology and Biophysics, University of California, Irvine, California 92697
| | - Alexander Huszagh
- From the Department of Physiology and Biophysics, University of California, Irvine, California 92697
| | - Yue Xu
- the Laboratory of Molecular Biology, NIDDK, National Institutes of Health, Bethesda, Maryland 20892
| | - Rosa Viner
- Thermo Fisher Scientific, San Jose, California 95134, and
| | - Sarah A Block
- the Department of Chemistry, University of California, Irvine, California 92697
| | - Peter Cimermancic
- the Departments of Bioengineering and Therapeutic Sciences and Pharmaceutical Chemistry, California Institute for Quantitative Biosciences, University of California, San Francisco, California 94143
| | - Scott D Rychnovsky
- the Department of Chemistry, University of California, Irvine, California 92697
| | - Yihong Ye
- the Laboratory of Molecular Biology, NIDDK, National Institutes of Health, Bethesda, Maryland 20892
| | - Andrej Sali
- the Departments of Bioengineering and Therapeutic Sciences and Pharmaceutical Chemistry, California Institute for Quantitative Biosciences, University of California, San Francisco, California 94143
| | - Lan Huang
- From the Department of Physiology and Biophysics, University of California, Irvine, California 92697,
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