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Chen S, Wang Y, Cui T, Zheng Y, Zhang F, Ma Q, Zhang C, Liu X. Characterization of three non-canonical N-glycosylation motifs indicates N glyco-A reduces DNA N6-methyladenine and N glyco-D alters G/F actin ratio in Phytophthora sojae. Int J Biol Macromol 2024; 277:133943. [PMID: 39025174 DOI: 10.1016/j.ijbiomac.2024.133943] [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] [Received: 04/08/2024] [Revised: 07/08/2024] [Accepted: 07/15/2024] [Indexed: 07/20/2024]
Abstract
Asparagine (Asn, N)-linked glycosylation is an abundant post-translational modification in which Asn, typically in Nglyco-X-S/T; X ≠ P motifs, are modified with N-glycans. It has essential regulatory roles in multicellular organisms. In this study, we systematically investigate the function of three N-glycosylation motifs (Nglyco-A, Nglyco-D and Nglyco-S) previously identified in Phytophthora sojae, through site-directed mutagenesis and functional assays. In P. sojae expressing glycosylation-dead variants pre-PsDMAP1N70A (Nglyco-A motif) or PsADFN64A (Nglyco-D motif), zoospore release or cyst germination is impaired. In particular, the pre-PsDMAP1N70A mutant reduces DNA methylation levels, and the PsADFN64A mutant disrupts the actin forms, which could explain the decrease in pathogenicity after N-glycosylation is destroyed. Similarly, P. sojae expressing PsNRXN132A (Nglyco-S motif) shows increased sensitivity to H2O2 and heat. Through autophagy or 26S proteasome pathway inhibition assays, we found that unglycosylated pre-PsDMAP1N70A and PsADFN64A are degraded via the 26S proteasome pathway, while the autophagy pathway is responsible for PsNRXN132A clearance. These findings demonstrate that glycosylation of these motifs regulates the stability and function of glycoproteins necessary for P. sojae growth, reproduction and pathogenicity, which expands the scope of known N-glycosylation regulatory functions in oomycetes.
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Affiliation(s)
- Shanshan Chen
- Department of Plant Pathology, China Agricultural University, Beijing 100193, China
| | - Yuke Wang
- Department of Plant Pathology, China Agricultural University, Beijing 100193, China
| | - Tongshan Cui
- Department of Plant Pathology, China Agricultural University, Beijing 100193, China
| | - Yuxin Zheng
- Department of Plant Pathology, China Agricultural University, Beijing 100193, China
| | - Fan Zhang
- Department of Plant Pathology, China Agricultural University, Beijing 100193, China
| | - Quanhe Ma
- Department of Plant Pathology, China Agricultural University, Beijing 100193, China
| | - Can Zhang
- Department of Plant Pathology, China Agricultural University, Beijing 100193, China.
| | - Xili Liu
- Department of Plant Pathology, China Agricultural University, Beijing 100193, China; State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling 712100, China.
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2
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Zbieralski K, Staszewski J, Konczak J, Lazarewicz N, Nowicka-Kazmierczak M, Wawrzycka D, Maciaszczyk-Dziubinska E. Multilevel Regulation of Membrane Proteins in Response to Metal and Metalloid Stress: A Lesson from Yeast. Int J Mol Sci 2024; 25:4450. [PMID: 38674035 PMCID: PMC11050377 DOI: 10.3390/ijms25084450] [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] [Received: 03/07/2024] [Revised: 04/06/2024] [Accepted: 04/16/2024] [Indexed: 04/28/2024] Open
Abstract
In the face of flourishing industrialization and global trade, heavy metal and metalloid contamination of the environment is a growing concern throughout the world. The widespread presence of highly toxic compounds of arsenic, antimony, and cadmium in nature poses a particular threat to human health. Prolonged exposure to these toxins has been associated with severe human diseases, including cancer, diabetes, and neurodegenerative disorders. These toxins are known to induce analogous cellular stresses, such as DNA damage, disturbance of redox homeostasis, and proteotoxicity. To overcome these threats and improve or devise treatment methods, it is crucial to understand the mechanisms of cellular detoxification in metal and metalloid stress. Membrane proteins are key cellular components involved in the uptake, vacuolar/lysosomal sequestration, and efflux of these compounds; thus, deciphering the multilevel regulation of these proteins is of the utmost importance. In this review, we summarize data on the mechanisms of arsenic, antimony, and cadmium detoxification in the context of membrane proteome. We used yeast Saccharomyces cerevisiae as a eukaryotic model to elucidate the complex mechanisms of the production, regulation, and degradation of selected membrane transporters under metal(loid)-induced stress conditions. Additionally, we present data on orthologues membrane proteins involved in metal(loid)-associated diseases in humans.
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Affiliation(s)
| | | | | | | | | | | | - Ewa Maciaszczyk-Dziubinska
- Department of Genetics and Cell Physiology, Faculty of Biological Sciences, University of Wroclaw, 50-328 Wroclaw, Poland; (K.Z.); (J.S.); (J.K.); (N.L.); (M.N.-K.); (D.W.)
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3
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Bao Z, Gao Y, Song Y, Ding N, Li W, Wu Q, Zhang X, Zheng Y, Li J, Hu X. Construction of an Escherichia coli chassis for efficient biosynthesis of human-like N-linked glycoproteins. Front Bioeng Biotechnol 2024; 12:1370685. [PMID: 38572355 PMCID: PMC10987854 DOI: 10.3389/fbioe.2024.1370685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Accepted: 03/08/2024] [Indexed: 04/05/2024] Open
Abstract
The production of N-linked glycoproteins in genetically engineered Escherichia coli holds significant potential for reducing costs, streamlining bioprocesses, and enhancing customization. However, the construction of a stable and low-cost microbial cell factory for the efficient production of humanized N-glycosylated recombinant proteins remains a formidable challenge. In this study, we developed a glyco-engineered E. coli chassis to produce N-glycosylated proteins with the human-like glycan Gal-β-1,4-GlcNAc-β-1,3-Gal-β-1,3-GlcNAc-, containing the human glycoform Gal-β-1,4-GlcNAc-β-1,3-. Our initial efforts were to replace various loci in the genome of the E. coli XL1-Blue strain with oligosaccharyltransferase PglB and the glycosyltransferases LsgCDEF to construct the E. coli chassis. In addition, we systematically optimized the promoter regions in the genome to regulate transcription levels. Subsequently, utilizing a plasmid carrying the target protein, we have successfully obtained N-glycosylated proteins with 100% tetrasaccharide modification at a yield of approximately 320 mg/L. Furthermore, we constructed the metabolic pathway for sialylation using a plasmid containing a dual-expression cassette of the target protein and CMP-sialic acid synthesis in the tetrasaccharide chassis cell, resulting in a 40% efficiency of terminal α-2,3- sialylation and a production of 65 mg/L of homogeneously sialylated glycoproteins in flasks. Our findings pave the way for further exploration of producing different linkages (α-2,3/α-2,6/α-2,8) of sialylated human-like N-glycoproteins in the periplasm of the plug-and-play E. coli chassis, laying a strong foundation for industrial-scale production.
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Affiliation(s)
- Zixin Bao
- Academic Centre for Medical Research, Medical College, Dalian University, Dalian, China
| | - Yuting Gao
- Academic Centre for Medical Research, Medical College, Dalian University, Dalian, China
| | - Yitong Song
- Academic Centre for Medical Research, Medical College, Dalian University, Dalian, China
| | - Ning Ding
- Academic Centre for Medical Research, Medical College, Dalian University, Dalian, China
- Dalian Key Laboratory of Oligosaccharide Recombination and Recombinant Protein Modification, Dalian, China
| | - Wei Li
- Academic Centre for Medical Research, Medical College, Dalian University, Dalian, China
| | - Qiong Wu
- Academic Centre for Medical Research, Medical College, Dalian University, Dalian, China
| | - Xiaomei Zhang
- Academic Centre for Medical Research, Medical College, Dalian University, Dalian, China
| | - Yang Zheng
- Academic Centre for Medical Research, Medical College, Dalian University, Dalian, China
| | - Junming Li
- Department of Clinical Laboratory, Yantai Yuhuangding Hospital, Yantai, China
| | - Xuejun Hu
- Academic Centre for Medical Research, Medical College, Dalian University, Dalian, China
- Dalian Key Laboratory of Oligosaccharide Recombination and Recombinant Protein Modification, Dalian, China
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4
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Yin H, Zhu J. Methods for quantification of glycopeptides by liquid separation and mass spectrometry. MASS SPECTROMETRY REVIEWS 2023; 42:887-917. [PMID: 35099083 PMCID: PMC9339036 DOI: 10.1002/mas.21771] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 11/14/2021] [Accepted: 01/13/2022] [Indexed: 05/05/2023]
Abstract
Recent advances in analytical techniques provide the opportunity to quantify even low-abundance glycopeptides derived from complex biological mixtures, allowing for the identification of glycosylation differences between healthy samples and those derived from disease states. Herein, we discuss the sample preparation procedures and the mass spectrometry (MS) strategies that have facilitated glycopeptide quantification, as well as the standards used for glycopeptide quantification. For sample preparation, various glycopeptide enrichment methods are summarized including the columns used for glycopeptide separation in liquid chromatography separation. For MS analysis strategies, MS1 level-based quantification and MS2 level-based quantification are described, either with or without labeling, where we have covered isotope labeling, TMT/iTRAQ labeling, data dependent acquisition, data independent acquisition, multiple reaction monitoring, and parallel reaction monitoring. The strengths and weaknesses of these methods are compared, particularly those associated with the figures of merit that are important for clinical biomarker studies and the pathological and functional studies of glycoproteins in various diseases. Possible future developments for glycopeptide quantification are discussed.
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Affiliation(s)
- Haidi Yin
- Shenzhen Bay Laboratory, Shenzhen, Guangdong, 518132, China
- Correspondence to: Haidi Yin, Shenzhen Bay Laboratory, A1201, Shenzhen, Guangdong, 518132, China. Phone: 0755-26849276. , Jianhui Zhu, Department of Surgery, University of Michigan, 1150 West Medical Center Drive, Building MSRB1, Rm A500, Ann Arbor, MI 48109-0656, USA. Tel: 734-615-2567. Fax: 734-615-2088.
| | - Jianhui Zhu
- Department of Surgery, University of Michigan, Ann Arbor, MI 48109, USA
- Correspondence to: Haidi Yin, Shenzhen Bay Laboratory, A1201, Shenzhen, Guangdong, 518132, China. Phone: 0755-26849276. , Jianhui Zhu, Department of Surgery, University of Michigan, 1150 West Medical Center Drive, Building MSRB1, Rm A500, Ann Arbor, MI 48109-0656, USA. Tel: 734-615-2567. Fax: 734-615-2088.
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5
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Dupuis JH, Cheung LKY, Newman L, Dee DR, Yada RY. Precision cellular agriculture: The future role of recombinantly expressed protein as food. Compr Rev Food Sci Food Saf 2023; 22:882-912. [PMID: 36546356 DOI: 10.1111/1541-4337.13094] [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] [Received: 07/05/2022] [Revised: 11/16/2022] [Accepted: 11/27/2022] [Indexed: 12/24/2022]
Abstract
Cellular agriculture is a rapidly emerging field, within which cultured meat has attracted the majority of media attention in recent years. An equally promising area of cellular agriculture, and one that has produced far more actual food ingredients that have been incorporated into commercially available products, is the use of cellular hosts to produce soluble proteins, herein referred to as precision cellular agriculture (PCAg). In PCAg, specific animal- or plant-sourced proteins are expressed recombinantly in unicellular hosts-the majority of which are yeast-and harvested for food use. The numerous advantages of PCAg over traditional agriculture, including a smaller carbon footprint and more consistent products, have led to extensive research on its utility. This review is the first to survey proteins currently being expressed using PCAg for food purposes. A growing number of viable expression hosts and recent advances for increased protein yields and process optimization have led to its application for producing milk, egg, and muscle proteins; plant hemoglobin; sweet-tasting plant proteins; and ice-binding proteins. Current knowledge gaps present research opportunities for optimizing expression hosts, tailoring posttranslational modifications, and expanding the scope of proteins produced. Considerations for the expansion of PCAg and its implications on food regulation, society, ethics, and the environment are also discussed. Considering the current trajectory of PCAg, food proteins from any biological source can likely be expressed recombinantly and used as purified food ingredients to create novel and tailored food products.
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Affiliation(s)
- John H Dupuis
- Faculty of Land and Food Systems, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Lennie K Y Cheung
- Faculty of Land and Food Systems, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Lenore Newman
- Food and Agriculture Institute, University of the Fraser Valley, Abbotsford, British Columbia, Canada
| | - Derek R Dee
- Faculty of Land and Food Systems, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Rickey Y Yada
- Faculty of Land and Food Systems, The University of British Columbia, Vancouver, British Columbia, Canada
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6
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Ramírez AS, de Capitani M, Pesciullesi G, Kowal J, Bloch JS, Irobalieva RN, Reymond JL, Aebi M, Locher KP. Molecular basis for glycan recognition and reaction priming of eukaryotic oligosaccharyltransferase. Nat Commun 2022; 13:7296. [PMID: 36435935 PMCID: PMC9701220 DOI: 10.1038/s41467-022-35067-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 11/17/2022] [Indexed: 11/28/2022] Open
Abstract
Oligosaccharyltransferase (OST) is the central enzyme of N-linked protein glycosylation. It catalyzes the transfer of a pre-assembled glycan, GlcNAc2Man9Glc3, from a dolichyl-pyrophosphate donor to acceptor sites in secretory proteins in the lumen of the endoplasmic reticulum. Precise recognition of the fully assembled glycan by OST is essential for the subsequent quality control steps of glycoprotein biosynthesis. However, the molecular basis of the OST-donor glycan interaction is unknown. Here we present cryo-EM structures of S. cerevisiae OST in distinct functional states. Our findings reveal that the terminal glucoses (Glc3) of a chemo-enzymatically generated donor glycan analog bind to a pocket formed by the non-catalytic subunits WBP1 and OST2. We further find that binding either donor or acceptor substrate leads to distinct primed states of OST, where subsequent binding of the other substrate triggers conformational changes required for catalysis. This alternate priming allows OST to efficiently process closely spaced N-glycosylation sites.
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Affiliation(s)
- Ana S. Ramírez
- grid.5801.c0000 0001 2156 2780Institute of Molecular Biology and Biophysics, Eidgenössische Technische Hochschule (ETH), Zürich, Switzerland
| | - Mario de Capitani
- grid.5734.50000 0001 0726 5157Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland
| | - Giorgio Pesciullesi
- grid.5734.50000 0001 0726 5157Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland
| | - Julia Kowal
- grid.5801.c0000 0001 2156 2780Institute of Molecular Biology and Biophysics, Eidgenössische Technische Hochschule (ETH), Zürich, Switzerland
| | - Joël S. Bloch
- grid.5801.c0000 0001 2156 2780Institute of Molecular Biology and Biophysics, Eidgenössische Technische Hochschule (ETH), Zürich, Switzerland
| | - Rossitza N. Irobalieva
- grid.5801.c0000 0001 2156 2780Institute of Molecular Biology and Biophysics, Eidgenössische Technische Hochschule (ETH), Zürich, Switzerland
| | - Jean-Louis Reymond
- grid.5734.50000 0001 0726 5157Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland
| | - Markus Aebi
- grid.5801.c0000 0001 2156 2780Institute of Microbiology, Eidgenössische Technische Hochschule (ETH), Zürich, Switzerland
| | - Kaspar P. Locher
- grid.5801.c0000 0001 2156 2780Institute of Molecular Biology and Biophysics, Eidgenössische Technische Hochschule (ETH), Zürich, Switzerland
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7
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Engineering Proteins Containing Noncanonical Amino Acids on the Yeast Surface. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2022; 2491:491-559. [PMID: 35482204 DOI: 10.1007/978-1-0716-2285-8_23] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Yeast display has been used to advance many critical research areas, including the discovery of unique protein binders and biological therapeutics. In parallel, noncanonical amino acids (ncAAs) have been used to tailor antibody-drug conjugates and enable discovery of therapeutic leads. Together, these two technologies have allowed for generation of synthetic antibody libraries, where the introduction of ncAAs in yeast-displayed proteins allows for library screening for therapeutically relevant targets. The combination of yeast display with genetically encoded ncAAs increases the available chemistry in proteins and advances applications that require high-throughput strategies. In this chapter, we discuss methods for displaying proteins containing ncAAs on the yeast surface, generating and screening libraries of proteins containing ncAAs, preparing bioconjugates on the yeast surface in large scale, generating and screening libraries of aminoacyl-tRNA synthetases (aaRSs) for encoding ncAAs by using reporter constructs, and characterizing ncAA-containing proteins secreted from yeast. The experimental designs laid out in this chapter are generalizable for discovery of protein binders to a variety of targets and aaRS evolution to continue expanding the genetic code beyond what is currently available in yeast.
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8
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Pallares RM, An DD, Hébert S, Faulkner D, Loguinov A, Proctor M, Villalobos JA, Bjornstad KA, Rosen CJ, Vulpe C, Abergel RJ. Delineating toxicity mechanisms associated with MRI contrast enhancement through a multidimensional toxicogenomic profiling of gadolinium. Mol Omics 2022; 18:237-248. [PMID: 35040455 DOI: 10.1039/d1mo00267h] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Gadolinium is a metal used in contrast agents for magnetic resonance imaging. Although gadolinium is widely used in clinical settings, many concerns regarding its toxicity and bioaccumulation after gadolinium-based contrast agent administration have been raised and published over the last decade. To date, most toxicological studies have focused on identifying acute effects following gadolinium exposure, rather than investigating associated toxicity mechanisms. In this study, we employ functional toxicogenomics to assess mechanistic interactions of gadolinium with Saccharomyces cerevisiae. Furthermore, we determine which mechanisms are conserved in humans, and their implications for diseases related to the use of gadolinium-based contrast agents in medicine. A homozygous deletion pool of 4291 strains were screened to identify biological functions and pathways disturbed by the metal. Gene ontology and pathway enrichment analyses showed endocytosis and vesicle-mediated transport as the main yeast response to gadolinium, while certain metabolic processes, such as glycosylation, were the primary disrupted functions after the metal treatments. Cluster and protein-protein interaction network analyses identified proteins mediating vesicle-mediated transport through the Golgi apparatus and the vacuole, and vesicle cargo exocytosis as key components to reduce the metal toxicity. Moreover, the metal seemed to induce cytotoxicity by disrupting the function of enzymes (e.g. transferases and proteases) and chaperones involved in metabolic processes. Several of the genes and proteins associated with gadolinium toxicity are conserved in humans, suggesting that they may participate in pathologies linked to gadolinium-based contrast agent exposures. We thereby discuss the potential role of these conserved genes and gene products in gadolinium-induced nephrogenic systemic fibrosis, and propose potential prophylactic strategies to prevent its adverse health effects.
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Affiliation(s)
- Roger M Pallares
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
| | - Dahlia D An
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
| | - Solène Hébert
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
| | - David Faulkner
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
| | - Alex Loguinov
- Center for Environmental and Human Toxicology, Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, 32611, USA
| | - Michael Proctor
- Center for Environmental and Human Toxicology, Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, 32611, USA
| | - Jonathan A Villalobos
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
| | - Kathleen A Bjornstad
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
| | - Chris J Rosen
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
| | - Christopher Vulpe
- Center for Environmental and Human Toxicology, Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, 32611, USA
| | - Rebecca J Abergel
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA. .,Department of Nuclear Engineering, University of California, Berkeley, CA, 94720, USA
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9
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Neuhaus JD, Wild R, Eyring J, Irobalieva RN, Kowal J, Lin CW, Locher KP, Aebi M. Functional analysis of Ost3p and Ost6p containing yeast oligosaccharyltransferases. Glycobiology 2021; 31:1604-1615. [PMID: 34974622 DOI: 10.1093/glycob/cwab084] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 07/14/2021] [Accepted: 08/05/2021] [Indexed: 11/14/2022] Open
Abstract
The oligosaccharyltransferase (OST) is the central enzyme in the N-glycosylation pathway. It transfers a defined oligosaccharide from a lipid-linker onto the asparagine side chain of proteins. The yeast OST consists of eight subunits and exists in two catalytically distinct isoforms that differ in one subunit, Ost3p or Ost6p. The cryo-electron microscopy structure of the Ost6p containing complex was found to be highly similar to the Ost3p containing OST. OST enzymes with altered Ost3p/Ost6p subunits were generated and functionally analyzed. The three C-terminal transmembrane helices were responsible for the higher turnover-rate of the Ost3p vs. the Ost6p containing enzyme in vitro and the more severe hypoglycosylation in Ost3p lacking strains in vivo. Glycosylation of specific OST target sites required the N-terminal thioredoxin domain of Ost3p or Ost6p. This Ost3p/Ost6p dependence was glycosylation site but not protein specific. We concluded that the Ost3p/Ost6p subunits modulate the catalytic activity of OST and provide additional specificity for OST substrate recognition.
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Affiliation(s)
- Julia D Neuhaus
- Institute of Microbiology, Department of Biology, ETH Zurich, 8093 Zurich, Switzerland
| | - Rebekka Wild
- Institute of Molecular Biology and Biophysics, Department of Biology, ETH Zurich, 8093 Zurich, Switzerland.,Institut de Biologie Structurale, CNRS, CEA, Université Grenoble-Alpes, 38000 Grenoble, France
| | - Jillianne Eyring
- Institute of Microbiology, Department of Biology, ETH Zurich, 8093 Zurich, Switzerland
| | - Rossitza N Irobalieva
- Institute of Molecular Biology and Biophysics, Department of Biology, ETH Zurich, 8093 Zurich, Switzerland
| | - Julia Kowal
- Institute of Molecular Biology and Biophysics, Department of Biology, ETH Zurich, 8093 Zurich, Switzerland
| | - Chia-Wei Lin
- Institute of Microbiology, Department of Biology, ETH Zurich, 8093 Zurich, Switzerland.,Functional Genomic Center Zurich, 8057 Zurich, Switzerland
| | - Kaspar P Locher
- Institute of Molecular Biology and Biophysics, Department of Biology, ETH Zurich, 8093 Zurich, Switzerland
| | - Markus Aebi
- Institute of Microbiology, Department of Biology, ETH Zurich, 8093 Zurich, Switzerland
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10
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Gutierrez-Reyes CD, Jiang P, Atashi M, Bennett A, Yu A, Peng W, Zhong J, Mechref Y. Advances in mass spectrometry-based glycoproteomics: An update covering the period 2017-2021. Electrophoresis 2021; 43:370-387. [PMID: 34614238 DOI: 10.1002/elps.202100188] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 08/30/2021] [Accepted: 09/25/2021] [Indexed: 12/23/2022]
Abstract
Protein glycosylation is one of the most common posttranslational modifications, and plays an essential role in a wide range of biological processes such as immune response, intercellular signaling, inflammation, host-pathogen interaction, and protein stability. Glycoproteomics is a proteomics subfield dedicated to identifying and characterizing the glycans and glycoproteins in a given cell or tissue. Aberrant glycosylation has been associated with various diseases such as Alzheimer's disease, viral infections, inflammation, immune deficiencies, congenital disorders, and cancers. However, glycoproteomic analysis remains challenging because of the low abundance, site-specific heterogeneity, and poor ionization efficiency of glycopeptides during LC-MS analyses. Therefore, the development of sensitive and accurate approaches to efficiently characterize protein glycosylation is crucial. Methods such as metabolic labeling, enrichment, and derivatization of glycopeptides, coupled with different mass spectrometry techniques and bioinformatics tools, have been developed to achieve sophisticated levels of quantitative and qualitative analyses of glycoproteins. This review attempts to update the recent developments in the field of glycoproteomics reported between 2017 and 2021.
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Affiliation(s)
| | - Peilin Jiang
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas, USA
| | - Mojgan Atashi
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas, USA
| | - Andrew Bennett
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas, USA
| | - Aiying Yu
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas, USA
| | - Wenjing Peng
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas, USA
| | - Jieqiang Zhong
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas, USA
| | - Yehia Mechref
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas, USA
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11
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Eyring J, Lin CW, Ngwa EM, Boilevin J, Pesciullesi G, Locher KP, Darbre T, Reymond JL, Aebi M. Substrate specificities and reaction kinetics of the yeast oligosaccharyltransferase isoforms. J Biol Chem 2021; 296:100809. [PMID: 34023382 PMCID: PMC8191290 DOI: 10.1016/j.jbc.2021.100809] [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: 11/19/2020] [Revised: 05/07/2021] [Accepted: 05/19/2021] [Indexed: 12/02/2022] Open
Abstract
Oligosaccharyltransferase (OST) catalyzes the central step in N-linked protein glycosylation, the transfer of a preassembled oligosaccharide from its lipid carrier onto asparagine residues of secretory proteins. The prototypic hetero-octameric OST complex from the yeast Saccharomyces cerevisiae exists as two isoforms that contain either Ost3p or Ost6p, both noncatalytic subunits. These two OST complexes have different protein substrate specificities in vivo. However, their detailed biochemical mechanisms and the basis for their different specificities are not clear. The two OST complexes were purified from genetically engineered strains expressing only one isoform. The kinetic properties and substrate specificities were characterized using a quantitative in vitro glycosylation assay with short peptides and different synthetic lipid-linked oligosaccharide (LLO) substrates. We found that the peptide sequence close to the glycosylation sequon affected peptide affinity and turnover rate. The length of the lipid moiety affected LLO affinity, while the lipid double-bond stereochemistry had a greater influence on LLO turnover rates. The two OST complexes had similar affinities for both the peptide and LLO substrates but showed significantly different turnover rates. These data provide the basis for a functional analysis of the Ost3p and Ost6p subunits.
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Affiliation(s)
- Jillianne Eyring
- Institute of Microbiology, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - Chia-Wei Lin
- Institute of Microbiology, Department of Biology, ETH Zürich, Zürich, Switzerland; Functional Genomics Center Zürich, University of Zürich/ETH Zürich, Zürich, Switzerland
| | - Elsy Mankah Ngwa
- Institute of Microbiology, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - Jérémy Boilevin
- Department of Chemistry and Biochemistry, University of Berne, Bern, Switzerland
| | - Giorgio Pesciullesi
- Department of Chemistry and Biochemistry, University of Berne, Bern, Switzerland
| | - Kaspar P Locher
- Institute of Molecular Biology and Biophysics, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - Tamis Darbre
- Department of Chemistry and Biochemistry, University of Berne, Bern, Switzerland
| | - Jean-Louis Reymond
- Department of Chemistry and Biochemistry, University of Berne, Bern, Switzerland
| | - Markus Aebi
- Institute of Microbiology, Department of Biology, ETH Zürich, Zürich, Switzerland.
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12
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Wang C, Gao W, Yan S, Zhu XQ, Suo X, Liu X, Gupta N, Hu M. N-glycome and N-glycoproteome of a hematophagous parasitic nematode Haemonchus. Comput Struct Biotechnol J 2021; 19:2486-2496. [PMID: 34025939 PMCID: PMC8113779 DOI: 10.1016/j.csbj.2021.04.038] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 04/14/2021] [Accepted: 04/16/2021] [Indexed: 12/24/2022] Open
Abstract
N-glycosylation is a physiologically vital post-translational modification of proteins in eukaryotic organisms. Initial work on Haemonchus contortus - a blood-sucking nematode of ruminants with a broad geographical distribution - has shown that this parasite harbors N-glycans with exclusive chitobiose modifications. Besides, several immunogenic proteins (e.g., amino- and metallo-peptidases) are known to be N-glycosylated in adult worms. However, an informative atlas of N-glycosylation in H. contortus is not yet available. Herein, we report 291 N-glycosylated proteins with a total of 425 modification sites in the parasite. Among them, many peptidase families (e.g., peptidase C1 and M1) including potential vaccine targets were enriched. Notably, the glycan-rich conjugates are distributed primarily in the intestine and gonads of adult worms, and consequently hidden from the host's immune system. Collectively, these data provide a comprehensive atlas of N-glycosylation in a prevalent parasitic nematode while underlining its significance for infection, immunity and prevention.
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Key Words
- Con A, concanavalin A
- Fuc, fucose
- Gal, galactose
- Gal-Fuc, galactosylated fucose
- GalNAc, N-acetylgalactosamine
- GlcNAc, N-acetylglucosamine
- Glycopeptide
- HILIC, hydrophilic interaction chromatography
- Haemonchus contortus
- LC-MS/MS, liquid chromatography-tandem mass spectrometry
- MALDI-ToF MS, matrix-assisted laser desorption ionization-time of flight mass spectrometry
- Man, mannose
- Mass spectrometry
- N-glycan
- N-glycosylation
- OST, oligosaccharyltransferase
- PNGase A/F, peptide-N-glycosidase A/F
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Affiliation(s)
- Chunqun Wang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Wenjie Gao
- College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China,College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Shi Yan
- Institut für Parasitologie, Veterinärmedizinische Universität, Wien, Austria
| | - Xing-Quan Zhu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Xun Suo
- State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing, China
| | - Xin Liu
- College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Nishith Gupta
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China,Department of Molecular Parasitology, Faculty of Life Sciences, Humboldt University, Berlin, Germany,Department of Biological Sciences, Birla Institute of Technology and Science Pilani (BITS-P), Hyderabad, India
| | - Min Hu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China,Corresponding author at: College of Veterinary Medicine, Huazhong Agricultural University, No.1 Shizishan St., Wuhan, Hubei Province 430070, China.
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13
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Mathew C, Weiß RG, Giese C, Lin CW, Losfeld ME, Glockshuber R, Riniker S, Aebi M. Glycan-protein interactions determine kinetics of N-glycan remodeling. RSC Chem Biol 2021; 2:917-931. [PMID: 34212152 PMCID: PMC8207518 DOI: 10.1039/d1cb00019e] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
A hallmark of N-linked glycosylation in the secretory compartments of eukaryotic cells is the sequential remodeling of an initially uniform oligosaccharide to a site-specific, heterogeneous ensemble of glycostructures on mature proteins. To understand site-specific processing, we used protein disulfide isomerase (PDI), a model protein with five glycosylation sites, for molecular dynamics (MD) simulations and compared the result to a biochemical in vitro analysis with four different glycan processing enzymes. As predicted by an analysis of the accessibility of the N-glycans for their processing enzymes derived from the MD simulations, N-glycans at different glycosylation sites showed different kinetic properties for the processing enzymes. In addition, altering the tertiary structure of the glycoprotein PDI affected its N-glycan remodeling in a site-specific way. We propose that the observed differential N-glycan reactivities depend on the surrounding protein tertiary structure and lead to different glycan structures in the same protein through kinetically controlled processing pathways. Atomistic glycoprotein simulations reveal a site-specific availability of glycan substrates in time-resolved mass spectrometry of maturating enzyme kinetics.![]()
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Affiliation(s)
- Corina Mathew
- Institute of Microbiology, Department of Biology, Swiss Federal Institute of Technology, ETH Zürich 8093 Zürich Switzerland
| | - R Gregor Weiß
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology, ETH Zürich 8093 Zürich Switzerland
| | - Christoph Giese
- Institute of Molecular Biology & Biophysics, Department of Biology, Swiss Federal Institute of Technology, ETH Zürich 8093 Zürich Switzerland
| | - Chia-Wei Lin
- Institute of Microbiology, Department of Biology, Swiss Federal Institute of Technology, ETH Zürich 8093 Zürich Switzerland .,Functional Genomics Center Zürich 8057 Zürich Switzerland
| | - Marie-Estelle Losfeld
- Institute of Microbiology, Department of Biology, Swiss Federal Institute of Technology, ETH Zürich 8093 Zürich Switzerland
| | - Rudi Glockshuber
- Institute of Molecular Biology & Biophysics, Department of Biology, Swiss Federal Institute of Technology, ETH Zürich 8093 Zürich Switzerland
| | - Sereina Riniker
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology, ETH Zürich 8093 Zürich Switzerland
| | - Markus Aebi
- Institute of Microbiology, Department of Biology, Swiss Federal Institute of Technology, ETH Zürich 8093 Zürich Switzerland
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14
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Zhang C, Cai M, Chen S, Zhang F, Cui T, Xue Z, Wang W, Zhang B, Liu X. The consensus N glyco -X-S/T motif and a previously unknown N glyco -N-linked glycosylation are necessary for growth and pathogenicity of Phytophthora. Environ Microbiol 2021; 23:5147-5163. [PMID: 33728790 DOI: 10.1111/1462-2920.15468] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 03/10/2021] [Accepted: 03/15/2021] [Indexed: 11/26/2022]
Abstract
Asparagine (Asn, N)-linked glycosylation within Nglyco -X-S/T; X ≠ P motif is a ubiquitously distributed post-translational modification that participates in diverse cellular processes. In this work, N-glycosylation inhibitor was shown to prevent Phytophthora sojae growth, suggesting that N-glycosylation is necessary for oomycete development. We conducted a glycoproteomic analysis of P. sojae to identify and map N-glycosylated proteins and to quantify differentially expressed glycoproteins associated with mycelia, asexual cyst, and sexual oospore developmental stages. A total of 355 N-glycosylated proteins was found, containing 496 glycosites, potentially involved in glycan degradation, carbon metabolism, glycolysis, or other metabolic pathways. Through PNGase F deglycosylation assays and site-directed mutagenesis of a GPI transamidase protein (GPI16) upregulated in cysts and a heat shock protein 70 (HSP70) upregulated in oospores, we demonstrated that both proteins were N-glycosylated and that the Nglyco -N motif is a target site for asparagine - oligosaccharide linkage. Glycosite mutations of Asn 94 Nglyco -X-S/T in the GPI16 led to impaired cyst germination and pathogenicity, while mutation of the previously unknown Asn 270 Nglyco -N motif in HSP70 led to decreased oospore production. In addition to providing a map of the oomycete N-glycoproteome, this work confirms that P. sojae has evolved multiple N-glycosylation motifs essential for growth.
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Affiliation(s)
- Can Zhang
- Department of Plant Pathology, China Agricultural University, Beijing, 100193, China
| | - Meng Cai
- Department of Plant Pathology, China Agricultural University, Beijing, 100193, China
| | - Shanshan Chen
- Department of Plant Pathology, China Agricultural University, Beijing, 100193, China
| | - Fan Zhang
- Department of Plant Pathology, China Agricultural University, Beijing, 100193, China
| | - Tongshan Cui
- Department of Plant Pathology, China Agricultural University, Beijing, 100193, China
| | - Zhaolin Xue
- Department of Plant Pathology, China Agricultural University, Beijing, 100193, China
| | - Weizhen Wang
- Department of Plant Pathology, China Agricultural University, Beijing, 100193, China
| | - Borui Zhang
- Department of Plant Pathology, China Agricultural University, Beijing, 100193, China
| | - Xili Liu
- Department of Plant Pathology, China Agricultural University, Beijing, 100193, China.,State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, 712100, China
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15
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Delafield DG, Li L. Recent Advances in Analytical Approaches for Glycan and Glycopeptide Quantitation. Mol Cell Proteomics 2021; 20:100054. [PMID: 32576592 PMCID: PMC8724918 DOI: 10.1074/mcp.r120.002095] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Indexed: 12/13/2022] Open
Abstract
Growing implications of glycosylation in physiological occurrences and human disease have prompted intensive focus on revealing glycomic perturbations through absolute and relative quantification. Empowered by seminal methodologies and increasing capacity for detection, identification, and characterization, the past decade has provided a significant increase in the number of suitable strategies for glycan and glycopeptide quantification. Mass-spectrometry-based strategies for glycomic quantitation have grown to include metabolic incorporation of stable isotopes, deposition of mass difference and mass defect isotopic labels, and isobaric chemical labeling, providing researchers with ample tools for accurate and robust quantitation. Beyond this, workflows have been designed to harness instrument capability for label-free quantification, and numerous software packages have been developed to facilitate reliable spectrum scoring. In this review, we present and highlight the most recent advances in chemical labeling and associated techniques for glycan and glycopeptide quantification.
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Affiliation(s)
- Daniel G Delafield
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Lingjun Li
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA; School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA.
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16
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Ye Z, Vakhrushev SY. The Role of Data-Independent Acquisition for Glycoproteomics. Mol Cell Proteomics 2021; 20:100042. [PMID: 33372048 PMCID: PMC8724878 DOI: 10.1074/mcp.r120.002204] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 12/26/2020] [Accepted: 12/28/2020] [Indexed: 12/13/2022] Open
Abstract
Data-independent acquisition (DIA) is now an emerging method in bottom–up proteomics and capable of achieving deep proteome coverage and accurate label-free quantification. However, for post-translational modifications, such as glycosylation, DIA methodology is still in the early stage of development. The full characterization of glycoproteins requires site-specific glycan identification as well as subsequent quantification of glycan structures at each site. The tremendous complexity of glycosylation represents a significant analytical challenge in glycoproteomics. This review focuses on the development and perspectives of DIA methodology for N- and O-linked glycoproteomics and posits that DIA-based glycoproteomics could be a method of choice to address some of the challenging aspects of glycoproteomics. First, the current challenges in glycoproteomics and the basic principles of DIA are briefly introduced. DIA-based glycoproteomics is then summarized and described into four aspects based on the actual samples. Finally, we discussed the important challenges and future perspectives in the field. We believe that DIA can significantly facilitate glycoproteomic studies and contribute to the development of future advanced tools and approaches in the field of glycoproteomics. Protein glycosylation and challenges in glycoproteomics. Data-independent acquisition for deglycosylated and intact N-linked glycopeptides. Unbiased screening of oxonium ions from all glycopeptide precursors. Glyco–data-independent acquisition on mucin-type O-glycopeptides.
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Affiliation(s)
- Zilu Ye
- Departments of Cellular and Molecular Medicine, Faculty of Health Sciences, Copenhagen Center for Glycomics, University of Copenhagen, Copenhagen N, Denmark
| | - Sergey Y Vakhrushev
- Departments of Cellular and Molecular Medicine, Faculty of Health Sciences, Copenhagen Center for Glycomics, University of Copenhagen, Copenhagen N, Denmark.
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17
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Omura F, Takagi M, Kodama Y. Compromised chitin synthesis in lager yeast affects its Congo red resistance and release of mannoproteins from the cells. FEMS Microbiol Lett 2020; 367:5974272. [PMID: 33175116 DOI: 10.1093/femsle/fnaa181] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 11/08/2020] [Indexed: 11/14/2022] Open
Abstract
A mutant lager strain resistant to the cell wall-perturbing agent Congo red (CR) was isolated and the genetic alterations underlying CR resistance were investigated by whole genome sequencing. The parental lager strain was found to contain three distinct Saccharomyces cerevisiae (Sc)-type CHS6 (CHitin Synthase-related 6) alleles, two of which have one or two nonsense mutations in the open reading frame, leaving only one functional allele, whereas the functional allele was missing in the isolated CR-resistant strain. On the other hand, the Saccharomyces eubayanus-type CHS6 alleles shared by both the parental and mutant strains appeared to contribute poorly to chitin synthase-activating function. Therefore, the CR resistance of the mutant strain was attributable to the overall compromised activity of CHS6 gene products. The CR-resistant mutant cells exhibited less chitin production on the cell surface and smaller amounts of mannoprotein release into the medium. All these traits, in addition to the CR resistance, were complemented by the functional ScCHS6 gene. It is of great interest whether the frequent nonsense mutations found in ScCHS6 open reading frame in lager yeast strains are a consequence of the domestication process of lager yeast.
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Affiliation(s)
- Fumihiko Omura
- Suntory Global Innovation Center Ltd., 8-1-1 Seikadai, Seika-cho, Soraku-gun, Kyoto 619-0284, Japan
| | - Motoshige Takagi
- Suntory System Technology Ltd., 2-1-5 Doujima, Kita-ku, Osaka-shi, Osaka 530-8204, Japan
| | - Yukiko Kodama
- Suntory Global Innovation Center Ltd., 8-1-1 Seikadai, Seika-cho, Soraku-gun, Kyoto 619-0284, Japan
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18
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Yamasaki T, Kohda D. Uncoupling the hydrolysis of lipid-linked oligosaccharide from the oligosaccharyl transfer reaction by point mutations in yeast oligosaccharyltransferase. J Biol Chem 2020; 295:16072-16085. [PMID: 32938717 PMCID: PMC7681024 DOI: 10.1074/jbc.ra120.015013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 09/12/2020] [Indexed: 11/06/2022] Open
Abstract
Oligosaccharyltransferase (OST) is responsible for the first step in the N-linked glycosylation, transferring an oligosaccharide chain onto asparagine residues to create glycoproteins. In the absence of an acceptor asparagine, OST hydrolyzes the oligosaccharide donor, releasing free N-glycans (FNGs) into the lumen of the endoplasmic reticulum (ER). Here, we established a purification method for mutated OSTs using a high-affinity epitope tag attached to the catalytic subunit Stt3, from yeast cells co-expressing the WT OST to support growth. The purified OST protein with mutations is useful for wide-ranging biochemical experiments. We assessed the effects of mutations in the Stt3 subunit on the two enzymatic activities in vitro, as well as their effects on the N-glycan attachment and FNG content levels in yeast cells. We found that mutations in the first DXD motif increased the FNG generation activity relative to the oligosaccharyl transfer activity, both in vitro and in vivo, whereas mutations in the DK motif had the opposite effect; the decoupling of the two activities may facilitate future deconvolution of the reaction mechanism. The isolation of the mutated OSTs also enabled us to identify different enzymatic properties in OST complexes containing either the Ost3 or Ost6 subunit and to find a 15-residue peptide as a better-quality substrate than shorter peptides. This toolbox of mutants, substrates, and methods will be useful for investigations of the molecular basis and physiological roles of the OST enzymes in yeast and other organisms.
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Affiliation(s)
- Takahiro Yamasaki
- Division of Structural Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | - Daisuke Kohda
- Division of Structural Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan.
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19
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Zhou C, Schulz BL. Glycopeptide variable window SWATH for improved data independent acquisition glycoprotein analysis. Anal Biochem 2020; 597:113667. [PMID: 32119847 DOI: 10.1016/j.ab.2020.113667] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 02/24/2020] [Accepted: 02/26/2020] [Indexed: 01/06/2023]
Abstract
N-glycosylation plays an essential role in regulating protein folding and function in eukaryotic cells. Sequential window acquisition of all theoretical fragment ion spectra mass spectrometry (SWATH) has proven useful as a data independent acquisition (DIA) MS method for analysis of glycoproteins and their glycan modifications. By separating the entire m/z range into consecutive isolation windows, DIA-MS allows comprehensive MS data acquisition and high-sensitivity detection of molecules of interest. Variable width DIA windows allow optimal analyte measurement, as peptide ions are not evenly distributed across the full m/z range. However, the m/z distribution of glycopeptides is different to that of unmodified peptides because of their large glycan structures. Here, we improved the performance of DIA glycoproteomics by using variable width windows optimized for glycopeptides. This method allocates narrow windows at m/z ranges rich in glycopeptides, improving analytical specificity and performance. We show that related glycoforms must fall in separate windows to allow accurate glycopeptide measurement. We demonstrate the utility of the method by comparing the cell wall glycoproteomes of wild-type and N-glycan biosynthesis deficient yeast and showing improved measurement of glycopeptides with different glycan structures. Our results highlight the importance of appropriately optimized DIA methods for measurement of post-translationally modified peptides.
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Affiliation(s)
- Chun Zhou
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, 4072, Queensland, Australia
| | - Benjamin L Schulz
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, 4072, Queensland, Australia; Australian Infectious Disease Research Centre, The University of Queensland, St Lucia, 4072, Queensland, Australia; Centre for Biopharmaceutical Innovation, Australian Institute of Bioengineering and Nanotechnology, The University of Queensland, St Lucia, 4072, Queensland, Australia.
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20
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Chen XL, Liu C, Tang B, Ren Z, Wang GL, Liu W. Quantitative proteomics analysis reveals important roles of N-glycosylation on ER quality control system for development and pathogenesis in Magnaporthe oryzae. PLoS Pathog 2020; 16:e1008355. [PMID: 32092131 PMCID: PMC7058352 DOI: 10.1371/journal.ppat.1008355] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 03/05/2020] [Accepted: 01/27/2020] [Indexed: 11/27/2022] Open
Abstract
Genetic studies have shown essential functions of N-glycosylation during infection of the plant pathogenic fungi, however, systematic roles of N-glycosylation in fungi is still largely unknown. Biological analysis demonstrated N-glycosylated proteins were widely present at different development stages of Magnaporthe oryzae and especially increased in the appressorium and invasive hyphae. A large-scale quantitative proteomics analysis was then performed to explore the roles of N-glycosylation in M. oryzae. A total of 559 N-glycosites from 355 proteins were identified and quantified at different developmental stages. Functional classification to the N-glycosylated proteins revealed N-glycosylation can coordinate different cellular processes for mycelial growth, conidium formation, and appressorium formation. N-glycosylation can also modify key components in N-glycosylation, O-glycosylation and GPI anchor pathways, indicating intimate crosstalk between these pathways. Interestingly, we found nearly all key components of the endoplasmic reticulum quality control (ERQC) system were highly N-glycosylated in conidium and appressorium. Phenotypic analyses to the gene deletion mutants revealed four ERQC components, Gls1, Gls2, GTB1 and Cnx1, are important for mycelial growth, conidiation, and invasive hyphal growth in host cells. Subsequently, we identified the Gls1 N-glycosite N497 was important for invasive hyphal growth and partially required for conidiation, but didn’t affect colony growth. Mutation of N497 resulted in reduction of Gls1 in protein level, and localization from ER into the vacuole, suggesting N497 is important for protein stability of Gls1. Our study showed a snapshot of the N-glycosylation landscape in plant pathogenic fungi, indicating functions of this modification in cellular processes, developments and pathogenesis. The fungal pathogen Magnaporthe oryzae can cause rice blast and wheat blast diseases, which threatens worldwide food production. During infection, M. oryzae follows a sequence of distinct developmental stages adapted to survival and invasion of the host environment. M. oryzae attaches onto the host by the conidium, and then develops an appressorium to breach the host cuticle. After penetrating, it forms invasive hyphae to quickly spread in the host cells. Numerous genetic studies have focused on the mechanisms underlying each step in the infection process, but systemic approaches are needed for a broader, integrated understanding of regulatory events during M. oryzae pathogenesis. Many infection-related signaling events are regulated through post-translational protein modifications within the pathogen. N-linked glycosylation, in which a glycan moiety is added to the amide group of an asparagine residue, is an abundant modification known to be essential for M. oryzae infection. In this study, we employed a quantitative proteomics analysis to unravel the overall regulatory mechanisms of N-glycosylation at different developmental stages of M. oryzae. We detected changes in N-glycosylation levels at 559 glycosylated residues (N-glycosites) in 355 proteins during different stages, and determined that the ER quality control system is elaborately regulated by N-glycosylation. The insights gained will help us to better understand the regulatory mechanisms of infection in pathogenic fungi. These findings may be also important for developing novel strategies for fungal disease control.
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Affiliation(s)
- Xiao-Lin Chen
- The Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Caiyun Liu
- The Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Bozeng Tang
- The Sainsbury Laboratory, University of East Anglia, Norwich, United Kingdom
| | - Zhiyong Ren
- The Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Guo-Liang Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- Department of Plant Pathology, Ohio State University, Columbus, Ohio, United States of America
| | - Wende Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- * E-mail:
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21
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Shrimal S, Cherepanova NA, Mandon EC, Venev SV, Gilmore R. Asparagine-linked glycosylation is not directly coupled to protein translocation across the endoplasmic reticulum in Saccharomyces cerevisiae. Mol Biol Cell 2019; 30:2626-2638. [PMID: 31433728 PMCID: PMC6761772 DOI: 10.1091/mbc.e19-06-0330] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Mammalian cells express two oligosaccharyltransferase complexes, STT3A and STT3B, that have distinct roles in N-linked glycosylation. The STT3A complex interacts directly with the protein translocation channel to mediate glycosylation of proteins using an N-terminal-to-C-terminal scanning mechanism. N-linked glycosylation of proteins in budding yeast has been assumed to be a cotranslational reaction. We have compared glycosylation of several glycoproteins in yeast and mammalian cells. Prosaposin, a cysteine-rich protein that contains STT3A-dependent glycosylation sites, is poorly glycosylated in yeast cells and STT3A-deficient human cells. In contrast, a protein with extreme C-terminal glycosylation sites was efficiently glycosylated in yeast by a posttranslocational mechanism. Posttranslocational glycosylation was also observed for carboxypeptidase Y-derived reporter proteins that contain closely spaced acceptor sites. A comparison of two recent protein structures indicates that the yeast OST is unable to interact with the yeast heptameric Sec complex via an evolutionarily conserved interface due to occupation of the OST binding site by the Sec63 protein. The efficiency of glycosylation in yeast is not enhanced for proteins that are translocated by the Sec61 or Ssh1 translocation channels instead of the Sec complex. We conclude that N-linked glycosylation and protein translocation are not directly coupled in yeast cells.
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Affiliation(s)
- Shiteshu Shrimal
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605
| | - Natalia A Cherepanova
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605
| | - Elisabet C Mandon
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605
| | - Sergey V Venev
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, MA 01605
| | - Reid Gilmore
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605
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22
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Cherepanova NA, Venev SV, Leszyk JD, Shaffer SA, Gilmore R. Quantitative glycoproteomics reveals new classes of STT3A- and STT3B-dependent N-glycosylation sites. J Cell Biol 2019; 218:2782-2796. [PMID: 31296534 PMCID: PMC6683751 DOI: 10.1083/jcb.201904004] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 06/13/2019] [Accepted: 06/18/2019] [Indexed: 11/24/2022] Open
Abstract
Cherepanova et al. provide quantitative glycoproteomic analyses of human cells that lack either the STT3A or STT3B oligosaccharyltransferase (OST) complex, revealing new classes of STT3A- and STT3B-dependent glycosylation sites and indicating how cooperation between the OST complexes maximizes acceptor site occupancy in cellular glycoproteins. Human cells express two oligosaccharyltransferase complexes (STT3A and STT3B) with partially overlapping functions. The STT3A complex interacts directly with the protein translocation channel to mediate cotranslational glycosylation, while the STT3B complex can catalyze posttranslocational glycosylation. We used a quantitative glycoproteomics procedure to compare glycosylation of roughly 1,000 acceptor sites in wild type and mutant cells. Analysis of site occupancy data disclosed several new classes of STT3A-dependent acceptor sites including those with suboptimal flanking sequences and sites located within cysteine-rich protein domains. Acceptor sites located in short loops of multi-spanning membrane proteins represent a new class of STT3B-dependent site. Remarkably, the lumenal ER chaperone GRP94 was hyperglycosylated in STT3A-deficient cells, bearing glycans on five silent sites in addition to the normal glycosylation site. GRP94 was also hyperglycosylated in wild-type cells treated with ER stress inducers including thapsigargin, dithiothreitol, and NGI-1.
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Affiliation(s)
- Natalia A Cherepanova
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA
| | - Sergey V Venev
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, MA
| | - John D Leszyk
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA.,Mass Spectrometry Facility, University of Massachusetts Medical School, Shrewsbury, MA
| | - Scott A Shaffer
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA.,Mass Spectrometry Facility, University of Massachusetts Medical School, Shrewsbury, MA
| | - Reid Gilmore
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA
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23
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Xie C, Gong W, Zhu Z, Zhou Y, Yan L, Hu Z, Ai L, Peng Y. Mapping the Secretome and Its N-Linked Glycosylation of Pleurotus eryngii and Pleurotus ostreatus Grown on Hemp Stalks. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:5486-5495. [PMID: 31012315 DOI: 10.1021/acs.jafc.9b00061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Our previous research showed that Pleurotus eryngii and Pleurotus ostreatus were effective fungi for pretreatment of industrial hemp stalks to improve enzymatic saccharification. The secretomes of these two fungi were analyzed to search for the effective enzyme cocktails degrading hemp lignin during the pretreatment process. In total, 169 and 155 proteins were identified in Pleurotus eryngii and Pleurotus ostreatus, respectively, and 50% of the proteins involved in lignocellulose degradation were CAZymes. Because most of the extracellular proteins secreted by fungi are glycosylated proteins, the N-linked glycosylation of enzymes could be mapped. In total, 27 and 24 N-glycosylated peptides were detected in Pleurotus eryngii and Pleurotus ostreatus secretomes, respectively. N-Glycosylated peptides of laccase, GH92, exoglucanase, phenol oxidase, α-galactosidase, carboxylic ester hydrolase, and pectin lyase were identified. Deglycosylation could decrease enzymatic saccharification of hemp stalks. The activities of laccase, α-galactosidase, and phenol oxidase and the thermal stability of laccase were reduced after deglycosylation.
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Affiliation(s)
- Chunliang Xie
- Institute of Bast Fiber Crops , Chinese Academy of Agricultural Sciences , Changsha 410205 , China
| | - Wenbing Gong
- Institute of Bast Fiber Crops , Chinese Academy of Agricultural Sciences , Changsha 410205 , China
| | - Zuohua Zhu
- Institute of Bast Fiber Crops , Chinese Academy of Agricultural Sciences , Changsha 410205 , China
| | - Yingjun Zhou
- Institute of Bast Fiber Crops , Chinese Academy of Agricultural Sciences , Changsha 410205 , China
| | - Li Yan
- Institute of Bast Fiber Crops , Chinese Academy of Agricultural Sciences , Changsha 410205 , China
| | - Zhenxiu Hu
- Institute of Bast Fiber Crops , Chinese Academy of Agricultural Sciences , Changsha 410205 , China
| | - Lianzhong Ai
- Institute of Bast Fiber Crops , Chinese Academy of Agricultural Sciences , Changsha 410205 , China
- Shanghai Engineering Research Center of Food Microbiology, School of Medical Instrument and Food Engineering , University of Shanghai for Science and Technology , Shanghai 200093 , China
| | - Yuande Peng
- Institute of Bast Fiber Crops , Chinese Academy of Agricultural Sciences , Changsha 410205 , China
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24
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Medina-Cano D, Ucuncu E, Nguyen LS, Nicouleau M, Lipecka J, Bizot JC, Thiel C, Foulquier F, Lefort N, Faivre-Sarrailh C, Colleaux L, Guerrera IC, Cantagrel V. High N-glycan multiplicity is critical for neuronal adhesion and sensitizes the developing cerebellum to N-glycosylation defect. eLife 2018; 7:38309. [PMID: 30311906 PMCID: PMC6185108 DOI: 10.7554/elife.38309] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 10/01/2018] [Indexed: 12/14/2022] Open
Abstract
Proper brain development relies highly on protein N-glycosylation to sustain neuronal migration, axon guidance and synaptic physiology. Impairing the N-glycosylation pathway at early steps produces broad neurological symptoms identified in congenital disorders of glycosylation. However, little is known about the molecular mechanisms underlying these defects. We generated a cerebellum specific knockout mouse for Srd5a3, a gene involved in the initiation of N-glycosylation. In addition to motor coordination defects and abnormal granule cell development, Srd5a3 deletion causes mild N-glycosylation impairment without significantly altering ER homeostasis. Using proteomic approaches, we identified that Srd5a3 loss affects a subset of glycoproteins with high N-glycans multiplicity per protein and decreased protein abundance or N-glycosylation level. As IgSF-CAM adhesion proteins are critical for neuron adhesion and highly N-glycosylated, we observed impaired IgSF-CAM-mediated neurite outgrowth and axon guidance in Srd5a3 mutant cerebellum. Our results link high N-glycan multiplicity to fine-tuned neural cell adhesion during mammalian brain development.
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Affiliation(s)
- Daniel Medina-Cano
- Paris Descartes-Sorbonne Paris Cité University, Paris, France.,Developmental Brain Disorders Laboratory, Imagine Institute, INSERM UMR 1163, Paris, France
| | - Ekin Ucuncu
- Paris Descartes-Sorbonne Paris Cité University, Paris, France.,Developmental Brain Disorders Laboratory, Imagine Institute, INSERM UMR 1163, Paris, France
| | - Lam Son Nguyen
- Paris Descartes-Sorbonne Paris Cité University, Paris, France.,Developmental Brain Disorders Laboratory, Imagine Institute, INSERM UMR 1163, Paris, France
| | - Michael Nicouleau
- Paris Descartes-Sorbonne Paris Cité University, Paris, France.,Developmental Brain Disorders Laboratory, Imagine Institute, INSERM UMR 1163, Paris, France
| | - Joanna Lipecka
- Proteomics platform 3P5-Necker, Université Paris Descartes - Structure Fédérative de Recherche Necker, INSERM US24/CNRS UMS3633, Paris, France
| | | | - Christian Thiel
- Center for Child and Adolescent Medicine, Kinderheilkunde I, University of Heidelberg, Heidelberg, Germany
| | - François Foulquier
- Université Lille, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, CNRS, Lille, France
| | | | | | - Laurence Colleaux
- Paris Descartes-Sorbonne Paris Cité University, Paris, France.,Developmental Brain Disorders Laboratory, Imagine Institute, INSERM UMR 1163, Paris, France
| | - Ida Chiara Guerrera
- Proteomics platform 3P5-Necker, Université Paris Descartes - Structure Fédérative de Recherche Necker, INSERM US24/CNRS UMS3633, Paris, France
| | - Vincent Cantagrel
- Paris Descartes-Sorbonne Paris Cité University, Paris, France.,Developmental Brain Disorders Laboratory, Imagine Institute, INSERM UMR 1163, Paris, France
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25
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Wild R, Kowal J, Eyring J, Ngwa EM, Aebi M, Locher KP. Structure of the yeast oligosaccharyltransferase complex gives insight into eukaryotic N-glycosylation. Science 2018; 359:545-550. [PMID: 29301962 DOI: 10.1126/science.aar5140] [Citation(s) in RCA: 136] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 12/22/2017] [Indexed: 12/18/2022]
Abstract
Oligosaccharyltransferase (OST) is an essential membrane protein complex in the endoplasmic reticulum, where it transfers an oligosaccharide from a dolichol-pyrophosphate-activated donor to glycosylation sites of secretory proteins. Here we describe the atomic structure of yeast OST determined by cryo-electron microscopy, revealing a conserved subunit arrangement. The active site of the catalytic STT3 subunit points away from the center of the complex, allowing unhindered access to substrates. The dolichol-pyrophosphate moiety binds to a lipid-exposed groove of STT3, whereas two noncatalytic subunits and an ordered N-glycan form a membrane-proximal pocket for the oligosaccharide. The acceptor polypeptide site faces an oxidoreductase domain in stand-alone OST complexes or is immediately adjacent to the translocon, suggesting how eukaryotic OSTs efficiently glycosylate a large number of polypeptides before their folding.
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Affiliation(s)
- Rebekka Wild
- Institute of Molecular Biology and Biophysics, Department of Biology, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Julia Kowal
- Institute of Molecular Biology and Biophysics, Department of Biology, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Jillianne Eyring
- Institute of Microbiology, Department of Biology, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Elsy M Ngwa
- Institute of Microbiology, Department of Biology, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Markus Aebi
- Institute of Microbiology, Department of Biology, ETH Zurich, CH-8093 Zurich, Switzerland.
| | - Kaspar P Locher
- Institute of Molecular Biology and Biophysics, Department of Biology, ETH Zurich, CH-8093 Zurich, Switzerland.
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26
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Poljak K, Breitling J, Gauss R, Rugarabamu G, Pellanda M, Aebi M. Analysis of substrate specificity of Trypanosoma brucei oligosaccharyltransferases (OSTs) by functional expression of domain-swapped chimeras in yeast. J Biol Chem 2017; 292:20342-20352. [PMID: 29042445 DOI: 10.1074/jbc.m117.811133] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 10/11/2017] [Indexed: 11/06/2022] Open
Abstract
N-Linked protein glycosylation is an essential and highly conserved post-translational modification in eukaryotes. The transfer of a glycan from a lipid-linked oligosaccharide (LLO) donor to the asparagine residue of a nascent polypeptide chain is catalyzed by an oligosaccharyltransferase (OST) in the lumen of the endoplasmic reticulum (ER). Trypanosoma brucei encodes three paralogue single-protein OSTs called TbSTT3A, TbSTT3B, and TbSTT3C that can functionally complement the Saccharomyces cerevisiae OST, making it an ideal experimental system to study the fundamental properties of OST activity. We characterized the LLO and polypeptide specificity of all three TbOST isoforms and their chimeric forms in the heterologous expression host S. cerevisiae where we were able to apply yeast genetic tools and newly developed glycoproteomics methods. We demonstrated that TbSTT3A accepted LLO substrates ranging from Man5GlcNAc2 to Man7GlcNAc2 In contrast, TbSTT3B required more complex precursors ranging from Man6GlcNAc2 to Glc3Man9GlcNAc2 structures, and TbSTT3C did not display any LLO preference. Sequence differences between the isoforms cluster in three distinct regions. We have swapped the individual regions between different OST proteins and identified region 2 to influence the specificity toward the LLO and region 1 to influence polypeptide substrate specificity. These results provide a basis to further investigate the molecular mechanisms and contribution of single amino acids in OST interaction with its substrates.
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Affiliation(s)
- Kristina Poljak
- Institute of Microbiology, ETH Zurich, Vladimir-Prelog-Weg 4, CH-8093 Zurich, Switzerland
| | - Jörg Breitling
- Institute of Microbiology, ETH Zurich, Vladimir-Prelog-Weg 4, CH-8093 Zurich, Switzerland
| | - Robert Gauss
- Institute of Microbiology, ETH Zurich, Vladimir-Prelog-Weg 4, CH-8093 Zurich, Switzerland
| | - George Rugarabamu
- Institute of Microbiology, ETH Zurich, Vladimir-Prelog-Weg 4, CH-8093 Zurich, Switzerland
| | - Mauro Pellanda
- Institute of Microbiology, ETH Zurich, Vladimir-Prelog-Weg 4, CH-8093 Zurich, Switzerland
| | - Markus Aebi
- Institute of Microbiology, ETH Zurich, Vladimir-Prelog-Weg 4, CH-8093 Zurich, Switzerland.
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