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Clarke EC. Considerations for Glycoprotein Production. Methods Mol Biol 2024; 2762:329-351. [PMID: 38315375 DOI: 10.1007/978-1-0716-3666-4_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2024]
Abstract
This chapter is intended to provide insights for researchers aiming to choose an appropriate expression system for the production of recombinant glycoproteins. Producing glycoproteins is complex, as glycosylation patterns are determined by the availability and abundance of specific enzymes rather than a direct genetic blueprint. Furthermore, the cell systems often employed for protein production are evolutionarily distinct, leading to significantly different glycosylation when utilized for glycoprotein production. The selection of an appropriate production system depends on the intended applications and desired characteristics of the protein. Whether the goal is to produce glycoproteins mimicking native conditions or to intentionally alter glycan structures for specific purposes, such as enhancing immunogenicity in vaccines, understanding glycosylation present in the different systems and in different growth conditions is essential. This chapter will cover Escherichia coli, baculovirus/insect cell systems, Pichia pastoris, as well as different mammalian cell culture systems including Chinese hamster ovary (CHO) cells, human endothelial kidney (HEK) cell lines, and baby hamster kidney (BHK) cells.
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Affiliation(s)
- Elizabeth C Clarke
- Center for Global Health, Division of Infectious Diseases, Department of Internal Medicine, University of New Mexico, Albuquerque, NM, USA.
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2
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Chung SS, Bidstrup EJ, Hershewe JM, Warfel KF, Jewett MC, DeLisa MP. Ribosome Stalling of N-Linked Glycoproteins in Cell-Free Extracts. ACS Synth Biol 2022; 11:3892-3899. [PMID: 36399685 PMCID: PMC9764415 DOI: 10.1021/acssynbio.2c00311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Indexed: 11/21/2022]
Abstract
Ribosome display is a powerful in vitro method for selection and directed evolution of proteins expressed from combinatorial libraries. However, the ability to display proteins with complex post-translational modifications such as glycosylation is limited. To address this gap, we developed a set of complementary methods for producing stalled ribosome complexes that displayed asparagine-linked (N-linked) glycoproteins in conformations amenable to downstream functional and glycostructural interrogation. The ability to generate glycosylated ribosome-nascent chain (glycoRNC) complexes was enabled by integrating SecM-mediated translation arrest with methods for cell-free N-glycoprotein synthesis. This integration enabled a first-in-kind method for ribosome stalling of target proteins modified efficiently and site-specifically with different N-glycan structures. Moreover, the observation that encoding mRNAs remained stably attached to ribosomes provides evidence of a genotype-glycophenotype link between an arrested glycoprotein and its RNA message. We anticipate that our method will enable selection and evolution of N-glycoproteins with advantageous biological and biophysical properties.
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Affiliation(s)
- Sean S. Chung
- Biochemistry,
Molecular and Cell Biology, Cornell University, Ithaca, New York 14853, United States
| | - Erik J. Bidstrup
- Robert
F. Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Jasmine M. Hershewe
- Department
of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road Technological Institute E136, Evanston, Illinois 60208-3120, United States
- Center
for Synthetic Biology, Northwestern University, 2145 Sheridan Road Technological
Institute E136, Evanston, Illinois 60208-3120, United States
- Chemistry
of Life Processes Institute, Northwestern
University, 2170 Campus
Drive, Evanston, Illinois 60208-3120, United States
| | - Katherine F. Warfel
- Department
of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road Technological Institute E136, Evanston, Illinois 60208-3120, United States
- Center
for Synthetic Biology, Northwestern University, 2145 Sheridan Road Technological
Institute E136, Evanston, Illinois 60208-3120, United States
- Chemistry
of Life Processes Institute, Northwestern
University, 2170 Campus
Drive, Evanston, Illinois 60208-3120, United States
| | - Michael C. Jewett
- Department
of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road Technological Institute E136, Evanston, Illinois 60208-3120, United States
- Center
for Synthetic Biology, Northwestern University, 2145 Sheridan Road Technological
Institute E136, Evanston, Illinois 60208-3120, United States
- Chemistry
of Life Processes Institute, Northwestern
University, 2170 Campus
Drive, Evanston, Illinois 60208-3120, United States
| | - Matthew P. DeLisa
- Biochemistry,
Molecular and Cell Biology, Cornell University, Ithaca, New York 14853, United States
- Robert
F. Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, United States
- Cornell
Institute
of Biotechnology, Cornell University, Ithaca, New York 14853, United States
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3
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Pratama F, Linton D, Dixon N. Genetic and process engineering strategies for enhanced recombinant N-glycoprotein production in bacteria. Microb Cell Fact 2021; 20:198. [PMID: 34649588 PMCID: PMC8518210 DOI: 10.1186/s12934-021-01689-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 09/25/2021] [Indexed: 11/28/2022] Open
Abstract
Background The production of N-linked glycoproteins in genetically amenable bacterial hosts offers great potential for reduced cost, faster/simpler bioprocesses, greater customisation, and utility for distributed manufacturing of glycoconjugate vaccines and glycoprotein therapeutics. Efforts to optimize production hosts have included heterologous expression of glycosylation enzymes, metabolic engineering, use of alternative secretion pathways, and attenuation of gene expression. However, a major bottleneck to enhance glycosylation efficiency, which limits the utility of the other improvements, is the impact of target protein sequon accessibility during glycosylation. Results Here, we explore a series of genetic and process engineering strategies to increase recombinant N-linked glycosylation, mediated by the Campylobacter-derived PglB oligosaccharyltransferase in Escherichia coli. Strategies include increasing membrane residency time of the target protein by modifying the cleavage site of its secretion signal, and modulating protein folding in the periplasm by use of oxygen limitation or strains with compromised oxidoreductase or disulphide-bond isomerase activity. These approaches achieve up to twofold improvement in glycosylation efficiency. Furthermore, we also demonstrate that supplementation with the chemical oxidant cystine enhances the titre of glycoprotein in an oxidoreductase knockout strain by improving total protein production and cell fitness, while at the same time maintaining higher levels of glycosylation efficiency. Conclusions In this study, we demonstrate that improved protein glycosylation in the heterologous host could be achieved by mimicking the coordination between protein translocation, folding and glycosylation observed in native host such as Campylobacter jejuni and mammalian cells. Furthermore, it provides insight into strain engineering and bioprocess strategies, to improve glycoprotein yield and titre, and to avoid physiological burden of unfolded protein stress upon cell growth. The process and genetic strategies identified herein will inform further optimisation and scale-up of heterologous recombinant N-glycoprotein production. Supplementary Information The online version contains supplementary material available at 10.1186/s12934-021-01689-x.
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Affiliation(s)
- Fenryco Pratama
- Manchester Institute of Biotechnology (MIB), The University of Manchester, Manchester, M1 7DN, UK.,Department of Chemistry, The University of Manchester, Manchester, M1 7DN, UK.,Microbial Biotechnology Research Group, School of Life Sciences and Technology, Institut Teknologi Bandung, Bandung, 40132, Indonesia
| | - Dennis Linton
- Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, M1 7DN, UK
| | - Neil Dixon
- Manchester Institute of Biotechnology (MIB), The University of Manchester, Manchester, M1 7DN, UK. .,Department of Chemistry, The University of Manchester, Manchester, M1 7DN, UK.
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4
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Cain JA, Dale AL, Sumer-Bayraktar Z, Solis N, Cordwell SJ. Identifying the targets and functions of N-linked protein glycosylation in Campylobacter jejuni. Mol Omics 2021; 16:287-304. [PMID: 32347268 DOI: 10.1039/d0mo00032a] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Campylobacter jejuni is a major cause of bacterial gastroenteritis in humans that is primarily associated with the consumption of inadequately prepared poultry products, since the organism is generally thought to be asymptomatic in avian species. Unlike many other microorganisms, C. jejuni is capable of performing extensive post-translational modification (PTM) of proteins by N- and O-linked glycosylation, both of which are required for optimal chicken colonization and human virulence. The biosynthesis and attachment of N-glycans to C. jejuni proteins is encoded by the pgl (protein glycosylation) locus, with the PglB oligosaccharyltransferase (OST) enabling en bloc transfer of a heptasaccharide N-glycan from a lipid carrier in the inner membrane to proteins exposed within the periplasm. Seventy-eight C. jejuni glycoproteins (represented by 134 sites of experimentally verified N-glycosylation) have now been identified, and include inner and outer membrane proteins, periplasmic proteins and lipoproteins, which are generally of poorly defined or unknown function. Despite our extensive knowledge of the targets of this apparently widespread process, we still do not fully understand the role N-glycosylation plays biologically, although several phenotypes, including wild-type stress resistance, biofilm formation, motility and chemotaxis have been related to a functional pgl system. Recent work has described enzymatic processes (nitrate reductase NapAB) and antibiotic efflux (CmeABC) as major targets requiring N-glycan attachment for optimal function, and experimental evidence also points to roles in cell binding via glycan-glycan interactions, protein complex formation and protein stability by conferring protection against host and bacterial proteolytic activity. Here we examine the biochemistry of the N-linked glycosylation system, define its currently known protein targets and discuss evidence for the structural and functional roles of this PTM in individual proteins and globally in C. jejuni pathogenesis.
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Affiliation(s)
- Joel A Cain
- School of Life and Environmental Sciences, The University of Sydney, 2006, Australia and Charles Perkins Centre, The University of Sydney, Level 4 East, The Hub Building (D17), 2006, Australia.
| | - Ashleigh L Dale
- School of Life and Environmental Sciences, The University of Sydney, 2006, Australia and Charles Perkins Centre, The University of Sydney, Level 4 East, The Hub Building (D17), 2006, Australia.
| | - Zeynep Sumer-Bayraktar
- School of Life and Environmental Sciences, The University of Sydney, 2006, Australia and Charles Perkins Centre, The University of Sydney, Level 4 East, The Hub Building (D17), 2006, Australia.
| | - Nestor Solis
- School of Life and Environmental Sciences, The University of Sydney, 2006, Australia
| | - Stuart J Cordwell
- School of Life and Environmental Sciences, The University of Sydney, 2006, Australia and Charles Perkins Centre, The University of Sydney, Level 4 East, The Hub Building (D17), 2006, Australia. and Discipline of Pathology, School of Medical Sciences, The University of Sydney, 2006, Australia and Sydney Mass Spectrometry, The University of Sydney, 2006, Australia
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5
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Hershewe JM, Warfel KF, Iyer SM, Peruzzi JA, Sullivan CJ, Roth EW, DeLisa MP, Kamat NP, Jewett MC. Improving cell-free glycoprotein synthesis by characterizing and enriching native membrane vesicles. Nat Commun 2021; 12:2363. [PMID: 33888690 PMCID: PMC8062659 DOI: 10.1038/s41467-021-22329-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 03/08/2021] [Indexed: 02/02/2023] Open
Abstract
Cell-free gene expression (CFE) systems from crude cellular extracts have attracted much attention for biomanufacturing and synthetic biology. However, activating membrane-dependent functionality of cell-derived vesicles in bacterial CFE systems has been limited. Here, we address this limitation by characterizing native membrane vesicles in Escherichia coli-based CFE extracts and describing methods to enrich vesicles with heterologous, membrane-bound machinery. As a model, we focus on bacterial glycoengineering. We first use multiple, orthogonal techniques to characterize vesicles and show how extract processing methods can be used to increase concentrations of membrane vesicles in CFE systems. Then, we show that extracts enriched in vesicle number also display enhanced concentrations of heterologous membrane protein cargo. Finally, we apply our methods to enrich membrane-bound oligosaccharyltransferases and lipid-linked oligosaccharides for improving cell-free N-linked and O-linked glycoprotein synthesis. We anticipate that these methods will facilitate on-demand glycoprotein production and enable new CFE systems with membrane-associated activities.
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Affiliation(s)
- Jasmine M Hershewe
- Department of Chemical and Biological Engineering, Northwestern University, Technological Institute E136, Evanston, IL, 60208, USA
- Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, 60208, USA
- Center for Synthetic Biology, Northwestern University, Technological Institute E136, Evanston, IL, 60208, USA
| | - Katherine F Warfel
- Department of Chemical and Biological Engineering, Northwestern University, Technological Institute E136, Evanston, IL, 60208, USA
- Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, 60208, USA
- Center for Synthetic Biology, Northwestern University, Technological Institute E136, Evanston, IL, 60208, USA
| | - Shaelyn M Iyer
- Department of Chemical and Biological Engineering, Northwestern University, Technological Institute E136, Evanston, IL, 60208, USA
| | - Justin A Peruzzi
- Department of Chemical and Biological Engineering, Northwestern University, Technological Institute E136, Evanston, IL, 60208, USA
- Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, 60208, USA
- Center for Synthetic Biology, Northwestern University, Technological Institute E136, Evanston, IL, 60208, USA
| | - Claretta J Sullivan
- Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson Air Force Base, Dayton, OH, 45433, USA
| | - Eric W Roth
- Northwestern University Atomic and Nanoscale Characterization and Experimentation (NUANCE) Center, Tech Institute A/B Wing A173, Evanston, IL, 60208, USA
| | - Matthew P DeLisa
- Robert F. Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, 14853, USA
- Nancy E. and Peter C. Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, 14853, USA
- Biomedical and Biological Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Neha P Kamat
- Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, 60208, USA
- Center for Synthetic Biology, Northwestern University, Technological Institute E136, Evanston, IL, 60208, USA
- Department of Biomedical Engineering, Northwestern University, Technological Institute E310, Evanston, IL, 60208, USA
| | - Michael C Jewett
- Department of Chemical and Biological Engineering, Northwestern University, Technological Institute E136, Evanston, IL, 60208, USA.
- Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, 60208, USA.
- Center for Synthetic Biology, Northwestern University, Technological Institute E136, Evanston, IL, 60208, USA.
- Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, IL, 60611, USA.
- Simpson Querrey Institute, Northwestern University, Chicago, IL, 60611, USA.
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6
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Fan F, Zhang Q, Lu D. Identification of N-glycosylation sites on AtERO1 and AtERO2 using a transient expression system. Biochem Biophys Res Commun 2020; 533:481-485. [PMID: 32977945 DOI: 10.1016/j.bbrc.2020.09.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 09/09/2020] [Indexed: 02/06/2023]
Abstract
N-glycosylation is an important protein modification that generally occurs at the Asn residue in an Asn-X-Ser/Thr sequon. Ero1 and its homologs play key roles in catalyzing the oxidative folding in the endoplasmic reticulum (ER). Recently, we found that Arabidopsis (Arabidopsis thaliana) ERO1 and AtERO2 displayed different characteristics in catalyzing oxidative protein folding in the ER. All known Ero1s are glycosylated proteins, including AtERO1 and AtERO2 that were analyzed when they were transiently translated in mammalian cells. However, the exact N-glycosylation sites on AtERO1 and AtERO2 remains to be determined. In this work, using a plant transient expression system, we identified the N-glycosylation sites on both AtERO1 and AtERO2. We found that AtERO1 has one N-glycosylation site, while AtERO2 contains two, all in the N-X-S/T sequons. Interestingly, we found that Ero1 homologs from human, rice, soybean and Arabidopsis, all have a conserved N-glycosylation site near the inner active site that reduces molecular oxygen and provides the oxidizing equivalents. The identification of N-glycosylation sites on AtERO1/2 proteins will help understand the function of N-glycosylation not only in AtERO1/2, but also in other Ero1 homologs.
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Affiliation(s)
- Fenggui Fan
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education & College of Life Sciences, Northwest University, Xi'an, Shaanxi, 710069, China; Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, Hebei, 050021, China. https://orcid.org/0000-0003-4157-9330
| | - Qiao Zhang
- College of Life Science, Hebei Normal University, Shijiazhuang, Hebei, 050024, China
| | - Dongping Lu
- Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, Hebei, 050021, China.
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7
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Arantes PR, Pedebos C, Polêto MD, Pol-Fachin L, Verli H. The Lazy Life of Lipid-Linked Oligosaccharides in All Life Domains. J Chem Inf Model 2020; 60:631-643. [PMID: 31769974 DOI: 10.1021/acs.jcim.9b00904] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Lipid-linked oligosaccharides (LLOs) play an important role in the N-glycosylation pathway as the donor substrate of oligosaccharyltransferases (OSTs), which are responsible for the en bloc transfer of glycan chains onto a nascent polypeptide. The lipid component of LLO in both eukarya and archaea consists of a dolichol, and an undecaprenol in prokarya, whereas the number of isoprene units may change between species. Given the potential relevance of LLOs and their related enzymes to diverse biotechnological applications, obtaining reliable LLO models from distinct domains of life could support further studies on complex formation and their processing by OSTs, as well as protein engineering on such systems. In this work, molecular modeling techniques, such as quantum mechanics calculations, molecular dynamics simulations, and metadynamics were employed to study eukaryotic (Glc3-Man9-GlcNAc2-PP-Dolichol), bacterial (Glc1-GalNAc5-Bac1-PP-Undecaprenol), and archaeal (Glc1-Man1-Gal1-Man1-Glc1-Gal1-Glc1-P-Dolichol) LLOs in membrane bilayers. Microsecond molecular dynamics simulations and metadynamics calculations of LLOs revealed that glycan chains are more prone to interact with the membrane lipid head groups, while the PP linkages are positioned at the lipid phosphate head groups level. The dynamics of isoprenoid chains embedded within the bilayer are described, and membrane dynamics and related properties are also investigated. Overall, there are similarities regarding the structure and dynamics of the eukaryotic, the bacterial, and the archaeal LLOs in bilayers, which can support the comprehension of their association with OSTs. These data may support future studies on the transferring mechanism of the oligosaccharide chain to an acceptor protein.
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Affiliation(s)
- Pablo R Arantes
- Centro de Biotecnologia , Universidade Federal do Rio Grande do Sul , Porto Alegre , RS 91509-900 , Brazil.,Laboratory of Genetic Toxicology , Federal University of Health Sciences of Porto Alegre - UFCSPA, Sarmento Leite, 245, Lab.714 , Porto Alegre , RS 90050-170 , Brazil
| | - Conrado Pedebos
- Centro de Biotecnologia , Universidade Federal do Rio Grande do Sul , Porto Alegre , RS 91509-900 , Brazil.,School of Chemistry , University of Southampton , Southampton , SO17 1BJ , U.K
| | - Marcelo D Polêto
- Centro de Biotecnologia , Universidade Federal do Rio Grande do Sul , Porto Alegre , RS 91509-900 , Brazil.,Departamento de Biologia Geral , Universidade Federal de Viçosa , Viçosa , MG 36570-000 , Brazil
| | | | - Hugo Verli
- Centro de Biotecnologia , Universidade Federal do Rio Grande do Sul , Porto Alegre , RS 91509-900 , Brazil
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8
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Nothaft H, Szymanski CM. New discoveries in bacterial N-glycosylation to expand the synthetic biology toolbox. Curr Opin Chem Biol 2019; 53:16-24. [DOI: 10.1016/j.cbpa.2019.05.032] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 05/21/2019] [Accepted: 05/31/2019] [Indexed: 12/20/2022]
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9
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Lassak J, Koller F, Krafczyk R, Volkwein W. Exceptionally versatile – arginine in bacterial post-translational protein modifications. Biol Chem 2019; 400:1397-1427. [DOI: 10.1515/hsz-2019-0182] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 06/01/2019] [Indexed: 12/24/2022]
Abstract
Abstract
Post-translational modifications (PTM) are the evolutionary solution to challenge and extend the boundaries of genetically predetermined proteomic diversity. As PTMs are highly dynamic, they also hold an enormous regulatory potential. It is therefore not surprising that out of the 20 proteinogenic amino acids, 15 can be post-translationally modified. Even the relatively inert guanidino group of arginine is subject to a multitude of mostly enzyme mediated chemical changes. The resulting alterations can have a major influence on protein function. In this review, we will discuss how bacteria control their cellular processes and develop pathogenicity based on post-translational protein-arginine modifications.
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Affiliation(s)
- Jürgen Lassak
- Center for Integrated Protein Science Munich (CiPSM), Department of Biology I, Microbiology , Ludwig-Maximilians-Universität München , Grosshaderner Strasse 2-4 , D-82152 Planegg , Germany
| | - Franziska Koller
- Center for Integrated Protein Science Munich (CiPSM), Department of Biology I, Microbiology , Ludwig-Maximilians-Universität München , Grosshaderner Strasse 2-4 , D-82152 Planegg , Germany
| | - Ralph Krafczyk
- Center for Integrated Protein Science Munich (CiPSM), Department of Biology I, Microbiology , Ludwig-Maximilians-Universität München , Grosshaderner Strasse 2-4 , D-82152 Planegg , Germany
| | - Wolfram Volkwein
- Center for Integrated Protein Science Munich (CiPSM), Department of Biology I, Microbiology , Ludwig-Maximilians-Universität München , Grosshaderner Strasse 2-4 , D-82152 Planegg , Germany
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10
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Yates LE, Natarajan A, Li M, Hale ME, Mills DC, DeLisa MP. Glyco-recoded Escherichia coli: Recombineering-based genome editing of native polysaccharide biosynthesis gene clusters. Metab Eng 2019; 53:59-68. [DOI: 10.1016/j.ymben.2019.02.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 02/06/2019] [Accepted: 02/10/2019] [Indexed: 12/21/2022]
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11
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Yamasaki T, Kohda D. A Radioisotope-free Oligosaccharyltransferase Assay Method. Bio Protoc 2019; 9:e3186. [PMID: 33654988 DOI: 10.21769/bioprotoc.3186] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 01/29/2019] [Accepted: 02/26/2019] [Indexed: 01/03/2023] Open
Abstract
Glycosylation of asparagine residues is widespread in Eukarya, and occurs in virtually all Archaea and some eubacterial species. A membrane-bound enzyme, oligosaccharyltransferase, catalyzes the transfer of an oligosaccharide chain from a sugar donor (lipid-linked oligosaccharide, LLO) to an asparagine residue in the consensus sequence, Asn-X-Ser/Thr (X ≠ Pro), in proteins. The in vitro oligosaccharyl transfer assay reaction mixture contains a detergent-solubilized oligosaccharyltransferase (OST), a sugar donor LLO, and a sugar acceptor peptide. Previous assay methods are problematic, in terms of the use of radioactive compounds and the cumbersome separation procedures using lectin binding or two-phase partitioning. Here, we describe a new oligosaccharyl transfer assay method, which is radioisotope-free and relies on a different separation mechanism. The glycopeptide products are separated from unreacted peptides by SDS-PAGE. A fluorescent dye is attached to the peptide substrate during custom peptide synthesis. The fluorescent imaging of the SDS-PAGE gels ensures high sensitivity and quantitative performance. The user-friendly PAGE format is particularly suitable for presentation in scientific papers. For illustrative applications, time-course and peptide library experiments are shown.
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Affiliation(s)
- Takahiro Yamasaki
- Division of Structural Biology, Medical Institute of Bioregulation, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
| | - Daisuke Kohda
- Division of Structural Biology, Medical Institute of Bioregulation, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
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12
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Jervis AJ, Wood AG, Cain JA, Butler JA, Frost H, Lord E, Langdon R, Cordwell SJ, Wren BW, Linton D. Functional analysis of the Helicobacter pullorum N-linked protein glycosylation system. Glycobiology 2018; 28:233-244. [PMID: 29340583 PMCID: PMC6025236 DOI: 10.1093/glycob/cwx110] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 01/10/2018] [Indexed: 11/23/2022] Open
Abstract
N-linked protein glycosylation systems operate in species from all three domains of life. The model bacterial N-linked glycosylation system from Campylobacter jejuni is encoded by pgl genes present at a single chromosomal locus. This gene cluster includes the pglB oligosaccharyltransferase responsible for transfer of glycan from lipid carrier to protein. Although all genomes from species of the Campylobacter genus contain a pgl locus, among the related Helicobacter genus only three evolutionarily related species (H. pullorum, H. canadensis and H. winghamensis) potentially encode N-linked protein glycosylation systems. Helicobacter putative pgl genes are scattered in five chromosomal loci and include two putative oligosaccharyltransferase-encoding pglB genes per genome. We have previously demonstrated the in vitro N-linked glycosylation activity of H. pullorum resulting in transfer of a pentasaccharide to a peptide at asparagine within the sequon (D/E)XNXS/T. In this study, we identified the first H. pullorum N-linked glycoprotein, termed HgpA. Production of histidine-tagged HgpA in the background of insertional knockout mutants of H. pullorum pgl/wbp genes followed by analysis of HgpA glycan structures demonstrated the role of individual gene products in the PglB1-dependent N-linked protein glycosylation pathway. Glycopeptide purification by zwitterionic-hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry identified six glycosites from five H. pullorum proteins, which was consistent with proteins reactive with a polyclonal antiserum generated against glycosylated HgpA. This study demonstrates functioning of a H. pullorum N-linked general protein glycosylation system.
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Affiliation(s)
- Adrian J Jervis
- Manchester Institute of Biotechnology, SYNBIOCHEM, University of Manchester, Manchester, UK
| | - Alison G Wood
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK
| | - Joel A Cain
- School of Molecular Bioscience and Charles Perkins Centre, The University of Sydney, 2006Australia
| | - Jonathan A Butler
- School of Healthcare Science, Manchester Metropolitan University, Manchester M1 5GD, UK
| | - Helen Frost
- Faculty of Biology, Medicine and Health, Michael Smith Building, University of Manchester, Manchester M13 9PT, UK
| | - Elizabeth Lord
- Faculty of Biology, Medicine and Health, Michael Smith Building, University of Manchester, Manchester M13 9PT, UK
| | - Rebecca Langdon
- Pathogen Molecular Biology Unit, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Stuart J Cordwell
- School of Molecular Bioscience and Charles Perkins Centre, The University of Sydney, 2006Australia
| | - Brendan W Wren
- Pathogen Molecular Biology Unit, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Dennis Linton
- Faculty of Biology, Medicine and Health, Michael Smith Building, University of Manchester, Manchester M13 9PT, UK
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13
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Abstract
Glycosylation is one of the most prevalent posttranslational modifications that profoundly affects the structure and functions of proteins in a wide variety of biological recognition events. However, the structural complexity and heterogeneity of glycoproteins, usually resulting from the variations of glycan components and/or the sites of glycosylation, often complicates detailed structure-function relationship studies and hampers the therapeutic applications of glycoproteins. To address these challenges, various chemical and biological strategies have been developed for producing glycan-defined homogeneous glycoproteins. This review highlights recent advances in the development of chemoenzymatic methods for synthesizing homogeneous glycoproteins, including the generation of various glycosynthases for synthetic purposes, endoglycosidase-catalyzed glycoprotein synthesis and glycan remodeling, and direct enzymatic glycosylation of polypeptides and proteins. The scope, limitation, and future directions of each method are discussed.
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Affiliation(s)
- Chao Li
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, United States
| | - Lai-Xi Wang
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, United States
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14
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Jaroentomeechai T, Stark JC, Natarajan A, Glasscock CJ, Yates LE, Hsu KJ, Mrksich M, Jewett MC, DeLisa MP. Single-pot glycoprotein biosynthesis using a cell-free transcription-translation system enriched with glycosylation machinery. Nat Commun 2018; 9:2686. [PMID: 30002445 PMCID: PMC6043479 DOI: 10.1038/s41467-018-05110-x] [Citation(s) in RCA: 113] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 06/06/2018] [Indexed: 12/13/2022] Open
Abstract
The emerging discipline of bacterial glycoengineering has made it possible to produce designer glycans and glycoconjugates for use as vaccines and therapeutics. Unfortunately, cell-based production of homogeneous glycoproteins remains a significant challenge due to cell viability constraints and the inability to control glycosylation components at precise ratios in vivo. To address these challenges, we describe a novel cell-free glycoprotein synthesis (CFGpS) technology that seamlessly integrates protein biosynthesis with asparagine-linked protein glycosylation. This technology leverages a glyco-optimized Escherichia coli strain to source cell extracts that are selectively enriched with glycosylation components, including oligosaccharyltransferases (OSTs) and lipid-linked oligosaccharides (LLOs). The resulting extracts enable a one-pot reaction scheme for efficient and site-specific glycosylation of target proteins. The CFGpS platform is highly modular, allowing the use of multiple distinct OSTs and structurally diverse LLOs. As such, we anticipate CFGpS will facilitate fundamental understanding in glycoscience and make possible applications in on demand biomanufacturing of glycoproteins. The ability to produce homogeneous glycoproteins is expected to advance fundamental understanding in glycoscience, but current in vivo-based production systems have several limitations. Here, the authors develop an E. coli extract-based one-pot system for customized production of N-linked glycoproteins.
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Affiliation(s)
- Thapakorn Jaroentomeechai
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Jessica C Stark
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL, 60208, USA.,Chemistry of Life Processes Institute, 2170 Campus Drive, Evanston, IL, 60208-3120, USA.,Center for Synthetic Biology, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208-3120, USA
| | - Aravind Natarajan
- Department of Microbiology, Cornell University, Ithaca, NY, 14853, USA
| | - Cameron J Glasscock
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Laura E Yates
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Karen J Hsu
- Department of Mechanical Engineering, Northwestern University, 2145 Sheridan Rd Technological Institute B224, Evanston, IL, 60208-3120, USA
| | - Milan Mrksich
- Center for Synthetic Biology, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208-3120, USA.,Department of Chemistry, Northwestern University, Evanston, IL, 60208, USA.,Department of Cell and Molecular Biology, Northwestern University, Chicago, IL, 60611, USA.,Department of Biomedical Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Michael C Jewett
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL, 60208, USA. .,Chemistry of Life Processes Institute, 2170 Campus Drive, Evanston, IL, 60208-3120, USA. .,Center for Synthetic Biology, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208-3120, USA.
| | - Matthew P DeLisa
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, 14853, USA. .,Department of Microbiology, Cornell University, Ithaca, NY, 14853, USA.
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15
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Yates LE, Mills DC, DeLisa MP. Bacterial Glycoengineering as a Biosynthetic Route to Customized Glycomolecules. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2018; 175:167-200. [PMID: 30099598 DOI: 10.1007/10_2018_72] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Bacteria have garnered increased interest in recent years as a platform for the biosynthesis of a variety of glycomolecules such as soluble oligosaccharides, surface-exposed carbohydrates, and glycoproteins. The ability to engineer commonly used laboratory species such as Escherichia coli to efficiently synthesize non-native sugar structures by recombinant expression of enzymes from various carbohydrate biosynthesis pathways has allowed for the facile generation of important products such as conjugate vaccines, glycosylated outer membrane vesicles, and a variety of other research reagents for studying and understanding the role of glycans in living systems. This chapter highlights some of the key discoveries and technologies for equipping bacteria with the requisite biosynthetic machinery to generate such products. As the bacterial glyco-toolbox continues to grow, these technologies are expected to expand the range of glycomolecules produced recombinantly in bacterial systems, thereby opening up this platform to an even larger number of applications.
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Affiliation(s)
- Laura E Yates
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, USA
| | - Dominic C Mills
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, USA
| | - Matthew P DeLisa
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, USA.
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16
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Dutta D, Mandal C, Mandal C. Unusual glycosylation of proteins: Beyond the universal sequon and other amino acids. Biochim Biophys Acta Gen Subj 2017; 1861:3096-3108. [DOI: 10.1016/j.bbagen.2017.08.025] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 08/03/2017] [Accepted: 08/14/2017] [Indexed: 12/11/2022]
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17
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Harvey DJ. Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update for 2011-2012. MASS SPECTROMETRY REVIEWS 2017; 36:255-422. [PMID: 26270629 DOI: 10.1002/mas.21471] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 01/15/2015] [Indexed: 06/04/2023]
Abstract
This review is the seventh update of the original article published in 1999 on the application of MALDI mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2012. General aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, and fragmentation are covered in the first part of the review and applications to various structural types constitute the remainder. The main groups of compound are oligo- and poly-saccharides, glycoproteins, glycolipids, glycosides, and biopharmaceuticals. Much of this material is presented in tabular form. Also discussed are medical and industrial applications of the technique, studies of enzyme reactions, and applications to chemical synthesis. © 2015 Wiley Periodicals, Inc. Mass Spec Rev 36:255-422, 2017.
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Affiliation(s)
- David J Harvey
- Department of Biochemistry, Oxford Glycobiology Institute, University of Oxford, Oxford, OX1 3QU, UK
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18
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Abstract
The glycosylation systems of Campylobacter jejuni (C. jejuni) are considered archetypal examples of both N- and O-linked glycosylations in the field of bacterial glycosylation. The discovery and characterization of these systems both have revealed important biological insight into C. jejuni and have led to the refinement and enhancement of methodologies to characterize bacterial glycosylation. In general, mass spectrometry-based characterization has become the preferred methodology for the study of C. jejuni glycosylation because of its speed, sensitivity, and ability to enable both qualitative and quantitative assessments of glycosylation events. In these experiments the generation of insightful data requires the careful selection of experimental approaches and mass spectrometry (MS) instrumentation. As such, it is essential to have a deep understanding of the technologies and approaches used for characterization of glycosylation events. Here we describe protocols for the initial characterization of C. jejuni glycoproteins using protein-/peptide-centric approaches and discuss considerations that can enhance the generation of insightful data.
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Affiliation(s)
- Nichollas E Scott
- Department of Microbiology and Immunology, Doherty Institute, The University of Melbourne, 792 Elizabeth St., Melbourne, Victoria, 3001, Australia.
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19
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Sugar and Spice Make Bacteria Not Nice: Protein Glycosylation and Its Influence in Pathogenesis. J Mol Biol 2016; 428:3206-3220. [DOI: 10.1016/j.jmb.2016.04.013] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 04/04/2016] [Accepted: 04/08/2016] [Indexed: 01/08/2023]
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20
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Ihssen J, Haas J, Kowarik M, Wiesli L, Wacker M, Schwede T, Thöny-Meyer L. Increased efficiency of Campylobacter jejuni N-oligosaccharyltransferase PglB by structure-guided engineering. Open Biol 2016; 5:140227. [PMID: 25833378 PMCID: PMC4422122 DOI: 10.1098/rsob.140227] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Conjugate vaccines belong to the most efficient preventive measures against life-threatening bacterial infections. Functional expression of N-oligosaccharyltransferase (N-OST) PglB of Campylobacter jejuni in Escherichia coli enables a simplified production of glycoconjugate vaccines in prokaryotic cells. Polysaccharide antigens of pathogenic bacteria can be covalently coupled to immunogenic acceptor proteins bearing engineered glycosylation sites. Transfer efficiency of PglBCj is low for certain heterologous polysaccharide substrates. In this study, we increased glycosylation rates for Salmonella enterica sv. Typhimurium LT2 O antigen (which lacks N-acetyl sugars) and Staphylococcus aureus CP5 polysaccharides by structure-guided engineering of PglB. A three-dimensional homology model of membrane-associated PglBCj, docked to the natural C. jejuni N-glycan attached to the acceptor peptide, was used to identify potential sugar-interacting residues as targets for mutagenesis. Saturation mutagenesis of an active site residue yielded the enhancing mutation N311V, which facilitated fivefold to 11-fold increased in vivo glycosylation rates as determined by glycoprotein-specific ELISA. Further rounds of in vitro evolution led to a triple mutant S80R-Q287P-N311V enabling a yield improvement of S. enterica LT2 glycoconjugates by a factor of 16. Our results demonstrate that bacterial N-OST can be tailored to specific polysaccharide substrates by structure-guided protein engineering.
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Affiliation(s)
- Julian Ihssen
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St Gallen 9014, Switzerland
| | - Jürgen Haas
- Biozentrum, University of Basel, Klingelbergstrasse 50/70, Basel 4056, Switzerland SIB Swiss Institute of Bioinformatics, Klingelbergstrasse 50/70, Basel 4056, Switzerland
| | | | - Luzia Wiesli
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St Gallen 9014, Switzerland
| | | | - Torsten Schwede
- Biozentrum, University of Basel, Klingelbergstrasse 50/70, Basel 4056, Switzerland SIB Swiss Institute of Bioinformatics, Klingelbergstrasse 50/70, Basel 4056, Switzerland
| | - Linda Thöny-Meyer
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St Gallen 9014, Switzerland
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21
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Mills DC, Jervis AJ, Abouelhadid S, Yates LE, Cuccui J, Linton D, Wren BW. Functional analysis of N-linking oligosaccharyl transferase enzymes encoded by deep-sea vent proteobacteria. Glycobiology 2015; 26:398-409. [PMID: 26610891 DOI: 10.1093/glycob/cwv111] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 11/20/2015] [Indexed: 01/04/2023] Open
Abstract
Bacterial N-linking oligosaccharyl transferases (OTase enzymes) transfer lipid-linked glycans to selected proteins in the periplasm and were first described in the intestinal pathogen Campylobacter jejuni, a member of the ε-proteobacteria-subdivision of bacteria. More recently, orthologues from other ε-proteobacterial Campylobacter and Helicobacter species and a δ-proteobacterium, Desulfovibrio desulfuricans, have been described, suggesting that these two subdivisions of bacteria may be a source of further N-linked protein glycosylation systems. Whole-genome sequencing of both ε- and δ-proteobacteria from deep-sea vent habitats, a rich source of species from these subdivisions, revealed putative ORFs encoding OTase enzymes and associated adjacent glycosyltransferases similar to the C. jejuni N-linked glycosylation locus. We expressed putative OTase ORFs from the deep-sea vent species Nitratiruptor tergarcus, Sulfurovum lithotrophicum and Deferribacter desulfuricans in Escherichia coli and showed that they were able to functionally complement the C. jejuni OTase, CjPglB. The enzymes were shown to possess relaxed glycan specificity, transferring diverse glycan structures and demonstrated different glycosylation sequon specificities. Additionally, a permissive D. desulfuricans acceptor protein was identified, and we provide evidence that the N-linked glycan synthesized by N. tergarcus and S. lithotrophicum contains an acetylated sugar at the reducing end. This work demonstrates that deep-sea vent bacteria encode functional N-glycosylation machineries and are a potential source of biotechnologically important OTase enzymes.
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Affiliation(s)
- Dominic C Mills
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, University of London, Keppel Street, London WC1E 7HT, UK
| | - Adrian J Jervis
- Faculty of Life Sciences, University of Manchester, Michael Smith Building, Manchester M13 9PT, UK
| | - Sherif Abouelhadid
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, University of London, Keppel Street, London WC1E 7HT, UK
| | - Laura E Yates
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, University of London, Keppel Street, London WC1E 7HT, UK
| | - Jon Cuccui
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, University of London, Keppel Street, London WC1E 7HT, UK
| | - Dennis Linton
- Faculty of Life Sciences, University of Manchester, Michael Smith Building, Manchester M13 9PT, UK
| | - Brendan W Wren
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, University of London, Keppel Street, London WC1E 7HT, UK
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22
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Ollis AA, Chai Y, Natarajan A, Perregaux E, Jaroentomeechai T, Guarino C, Smith J, Zhang S, DeLisa MP. Substitute sweeteners: diverse bacterial oligosaccharyltransferases with unique N-glycosylation site preferences. Sci Rep 2015; 5:15237. [PMID: 26482295 PMCID: PMC4894442 DOI: 10.1038/srep15237] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 08/28/2015] [Indexed: 02/01/2023] Open
Abstract
The central enzyme in the Campylobacter jejuni asparagine-linked glycosylation pathway is the oligosaccharyltransferase (OST), PglB, which transfers preassembled glycans to specific asparagine residues in target proteins. While C. jejuni PglB (CjPglB) can transfer many diverse glycan structures, the acceptor sites that it recognizes are restricted predominantly to those having a negatively charged residue in the -2 position relative to the asparagine. Here, we investigated the acceptor-site preferences for 23 homologs with natural sequence variation compared to CjPglB. Using an ectopic trans-complementation assay for CjPglB function in glycosylation-competent Escherichia coli, we demonstrated in vivo activity for 16 of the candidate OSTs. Interestingly, the OSTs from Campylobacter coli, Campylobacter upsaliensis, Desulfovibrio desulfuricans, Desulfovibrio gigas, and Desulfovibrio vulgaris, exhibited significantly relaxed specificity towards the -2 position compared to CjPglB. These enzymes glycosylated minimal N-X-T motifs in multiple targets and each followed unique, as yet unknown, rules governing acceptor-site preferences. One notable example is D. gigas PglB, which was the only bacterial OST to glycosylate the Fc domain of human immunoglobulin G at its native 'QYNST' sequon. Overall, we find that a subset of bacterial OSTs follow their own rules for acceptor-site specificity, thereby expanding the glycoengineering toolbox with previously unavailable biocatalytic diversity.
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Affiliation(s)
- Anne A Ollis
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853 USA
| | - Yi Chai
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853 USA
| | - Aravind Natarajan
- Department of Microbiology, Cornell University, Ithaca, NY 14853 USA
| | - Emily Perregaux
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853 USA.,Comparative Biomedical Sciences, Cornell University, Ithaca, NY 14853 USA
| | | | - Cassandra Guarino
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853 USA.,Comparative Biomedical Sciences, Cornell University, Ithaca, NY 14853 USA
| | - Jessica Smith
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853 USA
| | - Sheng Zhang
- Proteomics and Mass Spectrometry Core Facility, Cornell University, Ithaca, New York 14853
| | - Matthew P DeLisa
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853 USA.,Department of Microbiology, Cornell University, Ithaca, NY 14853 USA.,Comparative Biomedical Sciences, Cornell University, Ithaca, NY 14853 USA
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23
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Jang KS, Nani RR, Kalli A, Levin S, Müller A, Hess S, Reisman SE, Clemons WM. A cationic cysteine-hydrazide as an enrichment tool for the mass spectrometric characterization of bacterial free oligosaccharides. Anal Bioanal Chem 2015; 407:6181-90. [PMID: 26100547 PMCID: PMC4539134 DOI: 10.1007/s00216-015-8798-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 05/07/2015] [Accepted: 05/21/2015] [Indexed: 10/23/2022]
Abstract
In Campylobacterales and related ε-proteobacteria with N-linked glycosylation (NLG) pathways, free oligosaccharides (fOS) are released into the periplasmic space from lipid-linked precursors by the bacterial oligosaccharyltransferase (PglB). This hydrolysis results in the same molecular structure as the oligosaccharide that is transferred to a protein to be glycosylated. This allowed for the general elucidation of the fOS-branched structures and monosaccharides from a number of species using standard enrichment and mass spectrometry methods. To aid characterization of fOS, hydrazide chemistry has often been used for chemical modification of the reducing part of oligosaccharides resulting in better selectivity and sensitivity in mass spectrometry; however, the removal of the unreacted reagents used for the modification often causes the loss of the sample. Here, we develop a more robust method for fOS purification and characterize glycostructures using complementary tandem mass spectrometry (MS/MS) analysis. A cationic cysteine hydrazide derivative was synthesized to selectively isolate fOS from periplasmic fractions of bacteria. The cysteine hydrazide nicotinamide (Cyhn) probe possesses both thiol and cationic moieties. The former enables reversible conjugation to a thiol-activated solid support, while the latter improves the ionization signal during MS analysis. This enrichment was validated on the well-studied Campylobacter jejuni by identifying fOS from the periplasmic extracts. Using complementary MS/MS analysis, we approximated data of a known structure of the fOS from Campylobacter concisus. This versatile enrichment technique allows for the exploration of a diversity of protein glycosylation pathways.
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Affiliation(s)
- Kyoung-Soon Jang
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
- Biomedical Omics Group, Division of Bioconvergence Analysis, Korea Basic Science Institute, Cheongju 363-883, South Korea
| | - Roger R. Nani
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Anastasia Kalli
- Proteome Exploration Laboratory, Beckman Institute, California Institute of Technology, Pasadena, California 91125, United States
| | - Sergiy Levin
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Axel Müller
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Sonja Hess
- Proteome Exploration Laboratory, Beckman Institute, California Institute of Technology, Pasadena, California 91125, United States
| | - Sarah E. Reisman
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - William M. Clemons
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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24
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The sweet tooth of bacteria: common themes in bacterial glycoconjugates. Microbiol Mol Biol Rev 2015; 78:372-417. [PMID: 25184559 DOI: 10.1128/mmbr.00007-14] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Humans have been increasingly recognized as being superorganisms, living in close contact with a microbiota on all their mucosal surfaces. However, most studies on the human microbiota have focused on gaining comprehensive insights into the composition of the microbiota under different health conditions (e.g., enterotypes), while there is also a need for detailed knowledge of the different molecules that mediate interactions with the host. Glycoconjugates are an interesting class of molecules for detailed studies, as they form a strain-specific barcode on the surface of bacteria, mediating specific interactions with the host. Strikingly, most glycoconjugates are synthesized by similar biosynthesis mechanisms. Bacteria can produce their major glycoconjugates by using a sequential or an en bloc mechanism, with both mechanistic options coexisting in many species for different macromolecules. In this review, these common themes are conceptualized and illustrated for all major classes of known bacterial glycoconjugates, with a special focus on the rather recently emergent field of glycosylated proteins. We describe the biosynthesis and importance of glycoconjugates in both pathogenic and beneficial bacteria and in both Gram-positive and -negative organisms. The focus lies on microorganisms important for human physiology. In addition, the potential for a better knowledge of bacterial glycoconjugates in the emerging field of glycoengineering and other perspectives is discussed.
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25
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Naegeli A, Aebi M. Current Approaches to Engineering N-Linked Protein Glycosylation in Bacteria. Methods Mol Biol 2015; 1321:3-16. [PMID: 26082211 DOI: 10.1007/978-1-4939-2760-9_1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
N-Linked protein glycosylation is a common posttranslational protein modification in eukaryotes involved in many biological processes. As glycosylation is also important for the function and the pharmacokinetic properties of many protein therapeutics, there is an increasing interest in expression systems able to produce glycoproteins of well-defined structure. Bacterial expression hosts generally do not glycosylate proteins at all. However, the discovery of bacterial N-glycosylation systems has opened up a new route for the production of therapeutically interesting glycoproteins in glyco-engineered bacteria. This review offers an introduction to the many efforts taken to engineer bacteria in order to produce N-glycoproteins with defined eukaryotic glycan structures, completely novel protein glycoconjugates as well as to establish screening approaches for improvement and adaptation of the glycosylation machinery to specific applications.
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Affiliation(s)
- Andreas Naegeli
- Department of Biology, Institute of Microbiology, ETH Zurich, Zurich, Switzerland
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26
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Çelik E, Ollis AA, Lasanajak Y, Fisher AC, Gür G, Smith DF, DeLisa MP. Glycoarrays with engineered phages displaying structurally diverse oligosaccharides enable high-throughput detection of glycan-protein interactions. Biotechnol J 2014; 10:199-209. [PMID: 25263089 DOI: 10.1002/biot.201400354] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 08/21/2014] [Accepted: 09/24/2014] [Indexed: 02/02/2023]
Abstract
Glycan microarrays have become a powerful platform to investigate the interactions of carbohydrates with a variety of biomolecules. However, the number and diversity of glycans available for use in such arrays represent a key bottleneck in glycan array fabrication. To address this challenge, we describe a novel glycan array platform based on surface patterning of engineered glycophages that display unique carbohydrate epitopes. Specifically, we show that glycophages are compatible with surface immobilization procedures and that phage-displayed oligosaccharides retain the ability to be recognized by different glycan-binding proteins (e.g. antibodies and lectins) after immobilization. A key advantage of glycophage arrays is that large quantities of glycophages can be produced biosynthetically from recombinant bacteria and isolated directly from bacterial supernatants without laborious purification steps. Taken together, the glycophage array technology described here should help to expand the diversity of glycan libraries and provide a complement to the existing toolkit for high-throughput analysis of glycan-protein interactions.
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Affiliation(s)
- Eda Çelik
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, USA; Department of Chemical Engineering, Hacettepe University, Beytepe, Ankara, Turkey; Bioengineering Division, Institute of Science, Hacettepe University, Beytepe, Ankara, Turkey
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27
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Scott NE, Marzook NB, Cain JA, Solis N, Thaysen-Andersen M, Djordjevic SP, Packer NH, Larsen MR, Cordwell SJ. Comparative Proteomics and Glycoproteomics Reveal Increased N-Linked Glycosylation and Relaxed Sequon Specificity in Campylobacter jejuni NCTC11168 O. J Proteome Res 2014; 13:5136-50. [DOI: 10.1021/pr5005554] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
| | | | | | | | - Morten Thaysen-Andersen
- Department
of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
| | - Steven P. Djordjevic
- i3
Institute, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Nicolle H. Packer
- Department
of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
| | - Martin R. Larsen
- Protein
Research Group, Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense 5000, Denmark
| | - Stuart J. Cordwell
- Discipline
of Pathology, School of Medical Sciences, The University of Sydney, Sydney, New South Wales 2006, Australia
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28
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Jaffé SRP, Strutton B, Levarski Z, Pandhal J, Wright PC. Escherichia coli as a glycoprotein production host: recent developments and challenges. Curr Opin Biotechnol 2014; 30:205-10. [PMID: 25156401 DOI: 10.1016/j.copbio.2014.07.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 07/24/2014] [Accepted: 07/25/2014] [Indexed: 11/19/2022]
Abstract
Chinese Hamster Ovary cells are the most popular host expression system for the large-scale production of human therapeutic glycoproteins, but, the race to engineer Escherichia coli to perform glycosylation is gathering pace. The successful functional transfer of an N-glycosylation pathway from Campylobacter jejuni to Escherichia coli in 2002 can be considered as the crucial first engineering step. Here, we discuss the recent advancements in the field of N-glycosylation of recombinant therapeutic proteins in E. coli cells, from the manipulation of glycan composition, to the improvement in glycosylation efficiency, along with the challenges that remain before E. coli can be available as an industry host cell for economically viable glycoprotein production.
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Affiliation(s)
- Stephen R P Jaffé
- ChELSI Institute, Department of Chemical and Biological Engineering, Sir Robert Hadfield Building, Mappin Street, Sheffield S1 3JD, UK
| | - Benjamin Strutton
- ChELSI Institute, Department of Chemical and Biological Engineering, Sir Robert Hadfield Building, Mappin Street, Sheffield S1 3JD, UK
| | - Zdenko Levarski
- Comenius University in Bratislava, Faculty of Natural Sciences, Department of Molecular Biology, Mlynská dolina, 842 15 Bratislava 4, Slovak Republic
| | - Jagroop Pandhal
- ChELSI Institute, Department of Chemical and Biological Engineering, Sir Robert Hadfield Building, Mappin Street, Sheffield S1 3JD, UK
| | - Phillip C Wright
- ChELSI Institute, Department of Chemical and Biological Engineering, Sir Robert Hadfield Building, Mappin Street, Sheffield S1 3JD, UK.
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Ollis AA, Zhang S, Fisher AC, DeLisa MP. Engineered oligosaccharyltransferases with greatly relaxed acceptor-site specificity. Nat Chem Biol 2014; 10:816-22. [PMID: 25129029 DOI: 10.1038/nchembio.1609] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Accepted: 06/12/2014] [Indexed: 01/23/2023]
Abstract
The Campylobacter jejuni protein glycosylation locus (pgl) encodes machinery for asparagine-linked (N-linked) glycosylation and serves as the archetype for bacterial N-linked glycosylation. This machinery has been functionally transferred into Escherichia coli, enabling convenient mechanistic dissection of the N-linked glycosylation process in this genetically tractable host. Here we sought to identify sequence determinants in the oligosaccharyltransferase PglB that restrict its specificity to only those glycan acceptor sites containing a negatively charged residue at the -2 position relative to asparagine. This involved creation of a genetic assay, glycosylation of secreted N-linked acceptor proteins (glycoSNAP), that facilitates high-throughput screening of glycophenotypes in E. coli. Using this assay, we isolated several C. jejuni PglB variants that could glycosylate an array of noncanonical acceptor sequences, including one in a eukaryotic N-glycoprotein. These results underscore the utility of glycoSNAP for shedding light on poorly understood aspects of N-linked glycosylation and for engineering designer N-linked glycosylation biocatalysts.
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Affiliation(s)
- Anne A Ollis
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York, USA
| | - Sheng Zhang
- Proteomics and Mass Spectrometry Core Facility, Cornell University, Ithaca, New York, USA
| | | | - Matthew P DeLisa
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York, USA
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30
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Keck ZY, Angus AGN, Wang W, Lau P, Wang Y, Gatherer D, Patel AH, Foung SKH. Non-random escape pathways from a broadly neutralizing human monoclonal antibody map to a highly conserved region on the hepatitis C virus E2 glycoprotein encompassing amino acids 412-423. PLoS Pathog 2014; 10:e1004297. [PMID: 25122476 PMCID: PMC4133389 DOI: 10.1371/journal.ppat.1004297] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 06/23/2014] [Indexed: 12/15/2022] Open
Abstract
A challenge for hepatitis C virus (HCV) vaccine development is to define epitopes that are able to elicit protective antibodies against this highly diverse virus. The E2 glycoprotein region located at residues 412-423 is conserved and antibodies to 412-423 have broadly neutralizing activities. However, an adaptive mutation, N417S, is associated with a glycan shift in a variant that cannot be neutralized by a murine but by human monoclonal antibodies (HMAbs) against 412-423. To determine whether HCV escapes from these antibodies, we analyzed variants that emerged when cell culture infectious HCV virions (HCVcc) were passaged under increasing concentrations of a specific HMAb, HC33.1. Multiple nonrandom escape pathways were identified. Two pathways occurred in the context of an N-glycan shift mutation at N417T. At low antibody concentrations, substitutions of two residues outside of the epitope, N434D and K610R, led to variants having improved in vitro viral fitness and reduced sensitivity to HC33.1 binding and neutralization. At moderate concentrations, a S419N mutation occurred within 412-423 in escape variants that have greatly reduced sensitivity to HC33.1 but compromised viral fitness. Importantly, the variants generated from these pathways differed in their stability. N434D and K610R-associated variants were stable and became dominant as the virions were passaged. The S419N mutation reverted back to N419S when immune pressure was reduced by removing HC33.1. At high antibody concentrations, a mutation at L413I was observed in variants that were resistant to HC33.1 neutralization. Collectively, the combination of multiple escape pathways enabled the virus to persist under a wide range of antibody concentrations. Moreover, these findings pose a different challenge to vaccine development beyond the identification of highly conserved epitopes. It will be necessary for a vaccine to induce high potency antibodies that prevent the formation of escape variants, which can co-exist with lower potency or levels of neutralizing activities.
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Affiliation(s)
- Zhen-yong Keck
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Allan G. N. Angus
- MRC – University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Wenyan Wang
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Patrick Lau
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Yong Wang
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Derek Gatherer
- Division of Biomedical and Life Sciences, Lancaster University, Lancaster, United Kingdom
| | - Arvind H. Patel
- MRC – University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
- * E-mail: (AHP); (SKHF)
| | - Steven K. H. Foung
- Department of Pathology, Stanford University School of Medicine, Stanford, California, United States of America
- * E-mail: (AHP); (SKHF)
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31
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Jarrell KF, Ding Y, Meyer BH, Albers SV, Kaminski L, Eichler J. N-linked glycosylation in Archaea: a structural, functional, and genetic analysis. Microbiol Mol Biol Rev 2014; 78:304-41. [PMID: 24847024 PMCID: PMC4054257 DOI: 10.1128/mmbr.00052-13] [Citation(s) in RCA: 146] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
N-glycosylation of proteins is one of the most prevalent posttranslational modifications in nature. Accordingly, a pathway with shared commonalities is found in all three domains of life. While excellent model systems have been developed for studying N-glycosylation in both Eukarya and Bacteria, an understanding of this process in Archaea was hampered until recently by a lack of effective molecular tools. However, within the last decade, impressive advances in the study of the archaeal version of this important pathway have been made for halophiles, methanogens, and thermoacidophiles, combining glycan structural information obtained by mass spectrometry with bioinformatic, genetic, biochemical, and enzymatic data. These studies reveal both features shared with the eukaryal and bacterial domains and novel archaeon-specific aspects. Unique features of N-glycosylation in Archaea include the presence of unusual dolichol lipid carriers, the use of a variety of linking sugars that connect the glycan to proteins, the presence of novel sugars as glycan constituents, the presence of two very different N-linked glycans attached to the same protein, and the ability to vary the N-glycan composition under different growth conditions. These advances are the focus of this review, with an emphasis on N-glycosylation pathways in Haloferax, Methanococcus, and Sulfolobus.
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Affiliation(s)
- Ken F Jarrell
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Yan Ding
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Benjamin H Meyer
- Molecular Biology of Archaea, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Sonja-Verena Albers
- Molecular Biology of Archaea, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Lina Kaminski
- Department of Life Sciences, Ben Gurion University, Beersheva, Israel
| | - Jerry Eichler
- Department of Life Sciences, Ben Gurion University, Beersheva, Israel
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32
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Liu F, Vijayakrishnan B, Faridmoayer A, Taylor TA, Parsons TB, Bernardes GJL, Kowarik M, Davis BG. Rationally designed short polyisoprenol-linked PglB substrates for engineered polypeptide and protein N-glycosylation. J Am Chem Soc 2013; 136:566-9. [PMID: 24377322 DOI: 10.1021/ja409409h] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The lipid carrier specificity of the protein N-glycosylation enzyme C. jejuni PglB was tested using a logical, synthetic array of natural and unnatural C10, C20, C30, and C40 polyisoprenol sugar pyrophosphates, including those bearing repeating cis-prenyl units. Unusual, short, synthetically accessible C20 prenols (nerylnerol 1d and geranylnerol 1e) were shown to be effective lipid carriers for PglB sugar substrates. Kinetic analyses for PglB revealed clear K(M)-only modulation with lipid chain length, thereby implicating successful in vitro application at appropriate concentrations. This was confirmed by optimized, efficient in vitro synthesis allowing >90% of Asn-linked β-N-GlcNAc-ylated peptide and proteins. This reveals a simple, flexible biocatalytic method for glycoconjugate synthesis using PglB N-glycosylation machinery and varied chemically synthesized glycosylation donor precursors.
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Affiliation(s)
- Feng Liu
- Department of Chemistry, Chemistry Research Laboratory, Oxford University , Oxford OX1 3TA United Kingdom
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33
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Hochkoeppler A. Expanding the landscape of recombinant protein production in Escherichia coli. Biotechnol Lett 2013; 35:1971-81. [DOI: 10.1007/s10529-013-1396-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 06/26/2013] [Indexed: 12/11/2022]
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34
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Merritt JH, Ollis AA, Fisher AC, DeLisa MP. Glycans-by-design: Engineering bacteria for the biosynthesis of complex glycans and glycoconjugates. Biotechnol Bioeng 2013; 110:1550-64. [DOI: 10.1002/bit.24885] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 02/05/2013] [Accepted: 02/22/2013] [Indexed: 02/04/2023]
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35
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Musumeci MA, Hug I, Scott NE, Ielmini MV, Foster LJ, Wang PG, Feldman MF. In vitro activity of Neisseria meningitidis PglL O-oligosaccharyltransferase with diverse synthetic lipid donors and a UDP-activated sugar. J Biol Chem 2013; 288:10578-87. [PMID: 23460642 DOI: 10.1074/jbc.m112.432815] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Oligosaccharyltransferases (OTases) are enzymes that catalyze the transfer of an oligosaccharide from a lipid carrier to an acceptor molecule, commonly a protein. OTases are classified as N-OTases and O-OTases, depending on the nature of the glycosylation reaction. The N-OTases catalyze the glycan transfer to amide groups in asparagines in a reaction named N-linked glycosylation. The O-OTases are responsible for protein O-linked glycosylation, which involves the attachment of glycans to hydroxyl groups of serine or threonine residues. These enzymes exhibit a relaxed specificity and are able to transfer a variety of glycan structures to different protein acceptors. This property confers OTases with great biotechnological potential as these enzymes can produce glycoconjugates relevant to the pharmaceutical industry. Furthermore, OTases are thought to be involved in pathogenesis mechanisms. Several aspects of the functionality of OTases are not fully understood. In this work, we developed a novel approach to perform kinetic studies on PglL, the O-OTase from Neisseria meningitidis. We investigated the importance of the acyl moiety of the lipid glycan donor substrate on the functionality of PglL by testing the efficiency of glycosylation reactions using synthetic substrates carrying the same glycan structure but different acyl moieties. We found that PglL can function with many lipids as glycan donors, although the length and the conformation of the lipid moiety significantly influenced the catalytic efficiency. Interestingly, PglL was also able to transfer a monosaccharide employing its nucleotide-activated form, acting as a Leloir glycosyltransferase. These results provide new insights on the function and the evolution of oligosaccharyltransferases.
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Affiliation(s)
- Matias A Musumeci
- Alberta Glycomics Centre, Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
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36
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N-glycosylation of Campylobacter jejuni surface proteins promotes bacterial fitness. Infect Immun 2013; 81:1674-82. [PMID: 23460522 DOI: 10.1128/iai.01370-12] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Campylobacter jejuni is the etiologic agent of human bacterial gastroenteritis worldwide. In contrast, despite heavy colonization, C. jejuni maintains a commensal mode of existence in chickens. The consumption of contaminated chicken products is thought to be the principal mode of C. jejuni transmission to the human population. C. jejuni harbors a system for N-linked protein glycosylation that has been well characterized and modifies more than 60 periplasmic and membrane-bound proteins. However, the precise role of this modification in the biology of C. jejuni remains unexplored. We hypothesized that the N-glycans protect C. jejuni surface proteins from the action of gut proteases. The C. jejuni pglB mutant, deficient in the expression of the oligosaccharyltransferase, exhibited reduced growth in medium supplemented with chicken cecal contents (CCC) compared with that of wild-type (WT) cells. Inactivation of the cecal proteases by heat treatment or with protease inhibitors completely restored bacterial viability and partially rescued bacterial growth. Physiological concentrations of trypsin, but not chymotrypsin, also reduced C. jejuni pglB mutant CFU. Live or dead staining indicated that CCC preferentially influenced C. jejuni growth as opposed to bacterial viability. We identified multiple chicken cecal proteases by mass fingerprinting. The use of protease inhibitors that target specific classes indicated that both metalloproteases and serine proteases were involved in the attenuated growth of the oligosaccharyltransferase mutant. In conclusion, protein N-linked glycosylation of surface proteins may enhance C. jejuni fitness by protecting bacterial proteins from cleavage due to gut proteases.
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37
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Gerber S, Lizak C, Michaud G, Bucher M, Darbre T, Aebi M, Reymond JL, Locher KP. Mechanism of bacterial oligosaccharyltransferase: in vitro quantification of sequon binding and catalysis. J Biol Chem 2013; 288:8849-61. [PMID: 23382388 DOI: 10.1074/jbc.m112.445940] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
N-Linked glycosylation is an essential post-translational protein modification in the eukaryotic cell. The initial transfer of an oligosaccharide from a lipid carrier onto asparagine residues within a consensus sequon is catalyzed by oligosaccharyltransferase (OST). The first X-ray structure of a complete bacterial OST enzyme, Campylobacter lari PglB, was recently determined. To understand the mechanism of PglB, we have quantified sequon binding and glycosylation turnover in vitro using purified enzyme and fluorescently labeled, synthetic peptide substrates. Using fluorescence anisotropy, we determined a dissociation constant of 1.0 μm and a strict requirement for divalent metal ions for consensus (DQNAT) sequon binding. Using in-gel fluorescence detection, we quantified exceedingly low glycosylation rates that remained undetected using in vivo assays. We found that an alanine in the -2 sequon position, converting the bacterial sequon to a eukaryotic one, resulted in strongly lowered sequon binding, with in vitro turnover reduced 50,000-fold. A threonine is preferred over serine in the +2 sequon position, reflected by a 4-fold higher affinity and a 1.2-fold higher glycosylation rate. The interaction of the +2 sequon position with PglB is modulated by isoleucine 572. Our study demonstrates an intricate interplay of peptide and metal binding as the first step of protein N-glycosylation.
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Affiliation(s)
- Sabina Gerber
- Department of Biology, Institute of Molecular Biology and Biophysics, Zurich, Switzerland
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38
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Nothaft H, Szymanski CM. Bacterial protein N-glycosylation: new perspectives and applications. J Biol Chem 2013; 288:6912-20. [PMID: 23329827 DOI: 10.1074/jbc.r112.417857] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Protein glycosylation is widespread throughout all three domains of life. Bacterial protein N-glycosylation and its application to engineering recombinant glycoproteins continue to be actively studied. Here, we focus on advances made in the last 2 years, including the characterization of novel bacterial N-glycosylation pathways, examination of pathway enzymes and evolution, biological roles of protein modification in the native host, and exploitation of the N-glycosylation pathways to create novel vaccines and diagnostics.
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Affiliation(s)
- Harald Nothaft
- Alberta Glycomics Centre and Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada.
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39
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Ihssen J, Kowarik M, Wiesli L, Reiss R, Wacker M, Thöny-Meyer L. Structural insights from random mutagenesis of Campylobacter jejuni oligosaccharyltransferase PglB. BMC Biotechnol 2012; 12:67. [PMID: 23006740 PMCID: PMC3527161 DOI: 10.1186/1472-6750-12-67] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Accepted: 09/13/2012] [Indexed: 12/17/2022] Open
Abstract
Background Protein glycosylation is of fundamental importance in many biological systems. The discovery of N-glycosylation in bacteria and the functional expression of the N-oligosaccharyltransferase PglB of Campylobacter jejuni in Escherichia coli enabled the production of engineered glycoproteins and the study of the underlying molecular mechanisms. A particularly promising application for protein glycosylation in recombinant bacteria is the production of potent conjugate vaccines where polysaccharide antigens of pathogenic bacteria are covalently bound to immunogenic carrier proteins. Results In this study capsular polysaccharides of the clinically relevant pathogen Staphylococcus aureus serotype 5 (CP5) were expressed in Escherichia coli and linked in vivo to a detoxified version of Pseudomonas aeruginosa exotoxin (EPA). We investigated which amino acids of the periplasmic domain of PglB are crucial for the glycosylation reaction using a newly established 96-well screening system enabling the relative quantification of glycoproteins by enzyme-linked immunosorbent assay. A random mutant library was generated by error-prone PCR and screened for inactivating amino acid substitutions. In addition to 15 inactive variants with amino acid changes within the previously known, strictly conserved WWDYG motif of N-oligosaccharyltransferases, 8 inactivating mutations mapped to a flexible loop in close vicinity of the amide nitrogen atom of the acceptor asparagine as revealed in the crystal structure of the homologous enzyme C. lari PglB. The importance of the conserved loop residue H479 for glycosylation was confirmed by site directed mutagenesis, while a change to alanine of the adjacent, non-conserved L480 had no effect. In addition, we investigated functional requirements in the so-called MIV motif of bacterial N-oligosaccharyltransferases. Amino acid residues I571 and V575, which had been postulated to interact with the acceptor peptide, were subjected to cassette saturation mutagenesis. With the exception of I571C only hydrophobic residues were found in active variants. Variant I571V performed equally well as the wild type, cysteine at the same position reduced glycoprotein yield slightly, while a change to phenylalanine reduced activity by a factor of three. Conclusions This study provides novel structure-function relationships for the periplasmic domain of the Campylobacter jejuni N-oligosaccharyltransferase PglB and describes procedures for generating and screening oligosaccharyltransferase mutant libraries in an engineered E. coli system.
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Affiliation(s)
- Julian Ihssen
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Biomaterials, CH-9014, St, Gallen, Switzerland
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40
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Huang C, Bhaskaran R, Mohanty S. Eukaryotic N-glycosylation occurs via the membrane-anchored C-terminal domain of the Stt3p subunit of oligosaccharyltransferase. J Biol Chem 2012; 287:32450-8. [PMID: 22865878 DOI: 10.1074/jbc.m112.342253] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
N-glycosylation is an essential and highly conserved protein modification. In eukaryotes, it is catalyzed by a multisubunit membrane-associated enzyme, oligosaccharyltransferase (OT). We report the high resolution structure of the C-terminal domain of eukaryotic Stt3p. Unlike its soluble β-sheet-rich prokaryotic counterparts, our model reveals that the C-terminal domain of yeast Stt3p is highly helical and has an overall oblate spheroid-shaped structure containing a membrane-embedded region. Anchoring of this protein segment to the endoplasmic reticulum membrane is likely to bring the membrane-embedded donor substrate closer, thus facilitating glycosylation efficiency. Structural comparison of the region near the WWDYG signature motif revealed that the acceptor substrate-binding site of yeast OT strikingly resembles its prokaryotic counterparts, suggesting a conserved mechanism of N-glycosylation from prokaryotes to eukaryotes. Furthermore, comparison of the NMR and cryo-EM structures of yeast OT revealed that the molecular architecture of this acceptor substrate-recognizing domain has interesting spatial specificity for interactions with other essential OT subunits.
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Affiliation(s)
- Chengdong Huang
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, USA
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41
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Nothaft H, Scott NE, Vinogradov E, Liu X, Hu R, Beadle B, Fodor C, Miller WG, Li J, Cordwell SJ, Szymanski CM. Diversity in the protein N-glycosylation pathways within the Campylobacter genus. Mol Cell Proteomics 2012; 11:1203-19. [PMID: 22859570 DOI: 10.1074/mcp.m112.021519] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The foodborne bacterial pathogen, Campylobacter jejuni, possesses an N-linked protein glycosylation (pgl) pathway involved in adding conserved heptasaccharides to asparagine-containing motifs of >60 proteins, and releasing the same glycan into its periplasm as free oligosaccharides. In this study, comparative genomics of all 30 fully sequenced Campylobacter taxa revealed conserved pgl gene clusters in all but one species. Structural, phylogenetic and immunological studies showed that the N-glycosylation systems can be divided into two major groups. Group I includes all thermotolerant taxa, capable of growth at the higher body temperatures of birds, and produce the C. jejuni-like glycans. Within group I, the niche-adapted C. lari subgroup contain the smallest genomes among the epsilonproteobacteria, and are unable to glucosylate their pgl pathway glycans potentially reminiscent of the glucosyltransferase regression observed in the O-glycosylation system of Neisseria species. The nonthermotolerant Campylobacters, which inhabit a variety of hosts and niches, comprise group II and produce an unexpected diversity of N-glycan structures varying in length and composition. This includes the human gut commensal, C. hominis, which produces at least four different N-glycan structures, akin to the surface carbohydrate diversity observed in the well-studied commensal, Bacteroides. Both group I and II glycans are immunogenic and cell surface exposed, making these structures attractive targets for vaccine design and diagnostics.
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Affiliation(s)
- Harald Nothaft
- Alberta Glycomics Centre and Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada
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42
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Terra VS, Mills DC, Yates LE, Abouelhadid S, Cuccui J, Wren BW. Recent developments in bacterial protein glycan coupling technology and glycoconjugate vaccine design. J Med Microbiol 2012; 61:919-926. [DOI: 10.1099/jmm.0.039438-0] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Vanessa S. Terra
- London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Dominic C. Mills
- London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Laura E. Yates
- London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Sherif Abouelhadid
- London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Jon Cuccui
- London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Brendan W. Wren
- London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
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43
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An engineered eukaryotic protein glycosylation pathway in Escherichia coli. Nat Chem Biol 2012; 8:434-6. [PMID: 22446837 DOI: 10.1038/nchembio.921] [Citation(s) in RCA: 175] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Accepted: 01/24/2011] [Indexed: 12/28/2022]
Abstract
We performed bottom-up engineering of a synthetic pathway in Escherichia coli for the production of eukaryotic trimannosyl chitobiose glycans and the transfer of these glycans to specific asparagine residues in target proteins. The glycan biosynthesis was enabled by four eukaryotic glycosyltransferases, including the yeast uridine diphosphate-N-acetylglucosamine transferases Alg13 and Alg14 and the mannosyltransferases Alg1 and Alg2. By including the bacterial oligosaccharyltransferase PglB from Campylobacter jejuni, we successfully transferred glycans to eukaryotic proteins.
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44
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Gebhart C, Ielmini MV, Reiz B, Price NL, Aas FE, Koomey M, Feldman MF. Characterization of exogenous bacterial oligosaccharyltransferases in Escherichia coli reveals the potential for O-linked protein glycosylation in Vibrio cholerae and Burkholderia thailandensis. Glycobiology 2012; 22:962-74. [DOI: 10.1093/glycob/cws059] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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45
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Characterization of the structurally diverse N-linked glycans of Campylobacter species. J Bacteriol 2012; 194:2355-62. [PMID: 22389484 DOI: 10.1128/jb.00042-12] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The Gram-negative bacterium Campylobacter jejuni encodes an extensively characterized N-linked protein glycosylation system that modifies many surface proteins with a heptasaccharide glycan. In C. jejuni, the genes that encode the enzymes required for glycan biosynthesis and transfer to protein are located at a single pgl gene locus. Similar loci are also present in the genome sequences of all other Campylobacter species, although variations in gene content and organization are evident. In this study, we have demonstrated that only Campylobacter species closely related to C. jejuni produce glycoproteins that interact with both a C. jejuni N-linked-glycan-specific antiserum and a lectin known to bind to the C. jejuni N-linked glycan. In order to further investigate the structure of Campylobacter N-linked glycans, we employed an in vitro peptide glycosylation assay combined with mass spectrometry to demonstrate that Campylobacter species produce a range of structurally distinct N-linked glycans with variations in the number of sugar residues (penta-, hexa-, and heptasaccharides), the presence of branching sugars, and monosaccharide content. These data considerably expand our knowledge of bacterial N-linked glycan structure and provide a framework for investigating the role of glycosyltransferases and sugar biosynthesis enzymes in glycoprotein biosynthesis with practical implications for synthetic biology and glycoengineering.
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46
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Mechanisms and principles of N-linked protein glycosylation. Curr Opin Struct Biol 2012; 21:576-82. [PMID: 21978957 DOI: 10.1016/j.sbi.2011.08.005] [Citation(s) in RCA: 483] [Impact Index Per Article: 40.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Revised: 08/01/2011] [Accepted: 08/04/2011] [Indexed: 11/20/2022]
Abstract
N-linked glycosylation, a protein modification system present in all domains of life, is characterized by a high structural diversity of N-linked glycans found among different species and by a large number of proteins that are glycosylated. Based on structural, functional, and phylogenetic approaches, this review discusses the highly conserved processes that are at the basis of this unique general protein modification system.
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Guarino C, DeLisa MP. A prokaryote-based cell-free translation system that efficiently synthesizes glycoproteins. Glycobiology 2011; 22:596-601. [PMID: 22068020 DOI: 10.1093/glycob/cwr151] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Asparagine-linked (N-linked) protein glycosylation has been observed in all domains of life, including most recently in bacteria and is now widely considered a universal post-translational modification. However, cell-based production of homogeneous glycoproteins for laboratory and preparative purposes remains a significant challenge due in part to the complexity of this process in vivo. To address this issue, an easily available and highly controllable Escherichia coli-based cell-free system for the production of N-linked glycoproteins was developed. The method was created by coupling existing in vitro translation systems with an N-linked glycosylation pathway reconstituted from defined components. The translation/glycosylation system yielded efficiently glycosylated target proteins at a rate of hundreds of micrograms/milliliters in half a day. This is the first time a prokaryote-based cell-free protein synthesis system has generated N-linked glycoproteins.
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Affiliation(s)
- Cassandra Guarino
- Comparative Biomedical Sciences, Cornell University, Ithaca, NY 14853, USA
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Schwarz F, Fan YY, Schubert M, Aebi M. Cytoplasmic N-glycosyltransferase of Actinobacillus pleuropneumoniae is an inverting enzyme and recognizes the NX(S/T) consensus sequence. J Biol Chem 2011; 286:35267-74. [PMID: 21852240 DOI: 10.1074/jbc.m111.277160] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
N-Linked glycosylation is a frequent protein modification that occurs in all three domains of life. This process involves the transfer of a preassembled oligosaccharide from a lipid donor to asparagine side chains of polypeptides and is catalyzed by the membrane-bound oligosaccharyltransferase (OST). We characterized an alternative bacterial pathway wherein a cytoplasmic N-glycosyltransferase uses nucleotide-activated monosaccharides as donors to modify asparagine residues of peptides and proteins. N-Glycosyltransferase is an inverting glycosyltransferase and recognizes the NX(S/T) consensus sequence. It therefore exhibits similar acceptor site specificity as eukaryotic OST, despite the unrelated predicted structural architecture and the apparently different catalytic mechanism. The identification of an enzyme that integrates some of the features of OST in a cytoplasmic pathway defines a novel class of N-linked protein glycosylation found in pathogenic bacteria.
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Affiliation(s)
- Flavio Schwarz
- Institutes of Microbiology, Department of Biology, ETH Zürich, 8093 Zürich, Switzerland
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Lizak C, Gerber S, Numao S, Aebi M, Locher KP. X-ray structure of a bacterial oligosaccharyltransferase. Nature 2011; 474:350-5. [PMID: 21677752 DOI: 10.1038/nature10151] [Citation(s) in RCA: 288] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Accepted: 04/26/2011] [Indexed: 12/25/2022]
Abstract
Asparagine-linked glycosylation is a post-translational modification of proteins containing the conserved sequence motif Asn-X-Ser/Thr. The attachment of oligosaccharides is implicated in diverse processes such as protein folding and quality control, organism development or host-pathogen interactions. The reaction is catalysed by oligosaccharyltransferase (OST), a membrane protein complex located in the endoplasmic reticulum. The central, catalytic enzyme of OST is the STT3 subunit, which has homologues in bacteria and archaea. Here we report the X-ray structure of a bacterial OST, the PglB protein of Campylobacter lari, in complex with an acceptor peptide. The structure defines the fold of STT3 proteins and provides insight into glycosylation sequon recognition and amide nitrogen activation, both of which are prerequisites for the formation of the N-glycosidic linkage. We also identified and validated catalytically important, acidic amino acid residues. Our results provide the molecular basis for understanding the mechanism of N-linked glycosylation.
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Affiliation(s)
- Christian Lizak
- Institute of Microbiology, Department of Biology, ETH Zurich, CH-8093 Zurich, Switzerland
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Igura M, Kohda D. Quantitative assessment of the preferences for the amino acid residues flanking archaeal N-linked glycosylation sites. Glycobiology 2010; 21:575-83. [PMID: 21115605 DOI: 10.1093/glycob/cwq196] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Oligosaccharyltransferase (OST) catalyzes the transfer of an oligosaccharide to an asparagine residue in polypeptide chains. Using positional scanning peptide libraries, we assessed the effects of amino acid variations on the in vitro glycosylation efficiency within and adjacent to an N-glycosylation consensus, Asn-X-Ser/Thr, with an archaeal OST from Pyrococcus furiosus. The amino acid variations at the X(-2), X(-1) and X(+1) positions in the sequence X(-2)-X(-1)-Asn-X-Ser/Thr-X(+1) strongly influenced the glycosylation efficiency to a similar extent at position X. The rank orders of the amino acid preferences were unique at each site. We experimentally confirmed that the archaeal OST does not require an acidic residue at the -2 position, unlike the eubacterial OSTs. Pro was disfavored at the -1 and +1 positions, although the exclusion was not as strict as that at X, whereas Pro was the most favored amino acid residue among those studied at the -2 position. The overall amino acid preferences are correlated with a conformational propensity to extend around the sequon. The results of the library experiments revealed that the optimal acceptor sequence was PYNVTK, with a K(m) of 10 µM. The heat-stable, single-subunit OST of P. furiosus is a potential candidate enzyme for the production of recombinant glycoproteins in bacterial cells. Quantitative assessment of the amino acid preferences of the OST enzyme will facilitate the proper design of a production system.
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Affiliation(s)
- Mayumi Igura
- Division of Structural Biology, Medical Institute of Bioregulation, Kyushu University, Higashi-ku, Fukuoka, Japan
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