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Cardenas AJ, Thomas KS, Broden MW, Ferraro NJ, Pires MM, John CM, Jarvis GA, Criss AK. Neisseria gonorrhoeae scavenges host sialic acid for Siglec-mediated, complement-independent suppression of neutrophil activation. mBio 2024; 15:e0011924. [PMID: 38587424 PMCID: PMC11078009 DOI: 10.1128/mbio.00119-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Accepted: 03/12/2024] [Indexed: 04/09/2024] Open
Abstract
Gonorrhea, caused by the bacterium Neisseria gonorrhoeae (Gc), is characterized by neutrophilic influx to infection sites. Gc has developed mechanisms to resist killing by neutrophils that include modifications to its surface lipooligosaccharide (LOS). One such LOS modification is sialylation: Gc sialylates its terminal LOS sugars with cytidine-5'-monophosphate-N-acetylneuraminic acid, which is scavenged from the host using LOS sialyltransferase (Lst) since Gc cannot make its sialic acid. Sialylation enables sensitive strains of Gc to resist complement-mediated killing in a serum-dependent manner. However, little is known about the contribution of sialylation to complement-independent, direct Gc-neutrophil interactions. In the absence of complement, we found sialylated Gc expressing opacity-associated (Opa) proteins decreased the oxidative burst and granule exocytosis from primary human neutrophils. In addition, sialylated Opa+ Gc survived better than vehicle treated or Δlst Gc when challenged with neutrophils. However, Gc sialylation did not significantly affect Opa-dependent association with or internalization of Gc by neutrophils. Previous studies have implicated sialic acid-binding immunoglobulin-type lectins (Siglecs) in modulating neutrophil interactions with sialylated Gc. Blocking neutrophil Siglecs with antibodies that bind to their extracellular domains eliminated the ability of sialylated Opa+ Gc to suppress the oxidative burst and resist neutrophil killing. These findings highlight a new role for sialylation in Gc evasion of human innate immunity, with implications for the development of vaccines and therapeutics for gonorrhea. IMPORTANCE Neisseria gonorrhoeae, the bacterium that causes gonorrhea, is an urgent global health concern due to increasing infection rates, widespread antibiotic resistance, and its ability to thwart protective immune responses. The mechanisms by which Gc subverts protective immune responses remain poorly characterized. One way N. gonorrhoeae evades human immunity is by adding sialic acid that is scavenged from the host onto its lipooligosaccharide, using the sialyltransferase Lst. Here, we found that sialylation enhances N. gonorrhoeae survival from neutrophil assault and inhibits neutrophil activation, independently of the complement system. Our results implicate bacterial binding of sialic acid-binding lectins (Siglecs) on the neutrophil surface, which dampens neutrophil antimicrobial responses. This work identifies a new role for sialylation in protecting N. gonorrhoeae from cellular innate immunity, which can be targeted to enhance the human immune response in gonorrhea.
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Affiliation(s)
- Amaris J. Cardenas
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Keena S. Thomas
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Mary W. Broden
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Noel J. Ferraro
- Department of Chemistry, University of Virginia, Charlottesville, Virginia, USA
| | - Marcos M. Pires
- Department of Chemistry, University of Virginia, Charlottesville, Virginia, USA
| | - Constance M. John
- VA Medical Center and University of California, San Francisco, San Francisco, California, USA
| | - Gary A. Jarvis
- VA Medical Center and University of California, San Francisco, San Francisco, California, USA
| | - Alison K. Criss
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia, USA
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2
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Cardenas AJ, Thomas KS, Broden MW, Ferraro NJ, John CM, Pires MM, Jarvis GA, Criss AK. Neisseria gonorrhoeae scavenges host sialic acid for Siglec-mediated, complement-independent suppression of neutrophil activation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.17.576097. [PMID: 38293026 PMCID: PMC10827150 DOI: 10.1101/2024.01.17.576097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
Gonorrhea, caused by the bacterium Neisseria gonorrhoeae (Gc), is characterized by neutrophil influx to infection sites. Gc has developed mechanisms to resist killing by neutrophils that include modifications to its surface lipooligosaccharide (LOS). One such LOS modification is sialylation: Gc sialylates its terminal LOS sugars with cytidine-5'-monophosphate-N-acetylneuraminic acid (CMP-NANA) scavenged from the host using LOS sialyltransferase (Lst), since Gc cannot make its own sialic acid. Sialylation enables sensitive strains of Gc to resist complement-mediated killing in a serum-dependent manner. However, little is known about the contribution of sialylation to complement-independent, direct Gc-neutrophil interactions. In the absence of complement, we found sialylated Gc expressing opacity-associated (Opa) proteins decreased the oxidative burst and granule exocytosis from primary human neutrophils. In addition, sialylated Opa+ Gc survived better than vehicle treated or Δlst Gc when challenged with neutrophils. However, Gc sialylation did not significantly affect Opa-dependent association with or internalization of Gc by neutrophils. Previous studies have implicated sialic acid-binding immunoglobulin-type lectins (Siglecs) in modulating neutrophil interactions with sialylated Gc. Blocking neutrophil Siglecs with antibodies that bind to their extracellular domains eliminated the ability of sialylated Opa+ Gc to suppress oxidative burst and resist neutrophil killing. These findings highlight a new role for sialylation in Gc evasion of human innate immunity, with implications for the development of vaccines and therapeutics for gonorrhea.
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Affiliation(s)
- Amaris J Cardenas
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, USA
| | - Keena S. Thomas
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, USA
| | - Mary W. Broden
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, USA
| | - Noel J. Ferraro
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA
| | - Constance M. John
- VA Medical Center and University of California, San Francisco, San Francisco, CA, USA
| | - Marcos M. Pires
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA
| | - Gary A. Jarvis
- VA Medical Center and University of California, San Francisco, San Francisco, CA, USA
| | - Alison K. Criss
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, USA
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3
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Luo S, Liu Y, Hao T, Ma W, Luo Y, Wang S, Xu Z, Hu C, Wen L, Li T. Chemoenzymatic Total Synthesis of Haemophilus ducreyi Lipooligosaccharide Core Octasaccharides Containing Natural and Unnatural Sialic Acids. Org Lett 2023; 25:2312-2317. [PMID: 36972419 DOI: 10.1021/acs.orglett.3c00657] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
The first total synthesis of Haemophilus ducreyi lipooligosaccharide core octasaccharides containing natural and unnatural sialic acids has been achieved by an efficient chemoenzymatic approach. A highly convergent [3 + 3] coupling strategy was developed to chemically assemble a unique hexasaccharide bearing multiple rare higher-carbon sugars d-glycero-d-manno-heptose (d,d-Hep), l-glycero-d-manno-heptose (l,d-Hep), and 3-deoxy-α-d-manno-oct-2-ulosonic acid (Kdo). Key features include sequential one-pot glycosylations for oligosaccharide assembly and the construction of the challenging α-(1 → 5)-linked Hep-Kdo glycosidic bond by gold-catalyzed glycosylation with a glycosyl ortho-alkynylbenzoate donor. Furthermore, the sequential enzyme-catalyzed regio- and stereoselective introduction of a galactose residue using β-1,4-galactosyltransferase and different sialic acids using a one-pot multienzyme sialylation system was efficiently accomplished to provide the target octasaccharides.
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Affiliation(s)
- Shiwei Luo
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Yating Liu
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Tianhui Hao
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenjing Ma
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yawen Luo
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Shasha Wang
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Zhuojia Xu
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Chaoyu Hu
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Liuqing Wen
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Tiehai Li
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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4
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Wen Y, Zhang RY, Wang J, Zhou SH, Peng XQ, Ding D, Zhang ZM, Wei HW, Guo J. Novel sialoglycan linkage for constructing adjuvant-protein conjugate as potent vaccine for COVID-19. J Control Release 2023; 355:238-247. [PMID: 36716860 PMCID: PMC9907060 DOI: 10.1016/j.jconrel.2023.01.062] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 01/20/2023] [Accepted: 01/24/2023] [Indexed: 02/01/2023]
Abstract
Self-adjuvanting protein vaccines have been proved to be highly immunogenic with efficient codelivery of adjuvant and antigen. Current protein vaccines with built-in adjuvants are all modified at the peptide backbone of antigen protein, which could not achieve minor epitope interference and adjuvant multivalency at the same time. Herein, we developed a new conjugate strategy to construct effective adjuvant-protein vaccine with adjuvant cluster effect and minimal epitope interference. The toll-like receptor 7 agonist (TLR7a) is covalently conjugated on the terminal sialoglycans of SARS-CoV-2-S1 protein, leading to intracellular release of the small-molecule stimulators with greatly reduced risks of systemic toxicity. The resulting TLR7a-S1 conjugate elicited strong activation of immune cells in vitro, and potent antibody and cellular responses with a significantly enhanced Th1-bias in vivo. TLR7a-S1-induced antibody also effectively cross-neutralized all variants of concern. This sialoglycoconjugation approach to construct protein conjugate vaccines will have more applications to combat SARS-CoV-2 and other diseases.
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Affiliation(s)
- Yu Wen
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, International Joint Research Center for Intelligent Biosensing Technology and Health, Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, College of Chemistry, Central China Normal University, Wuhan 430079, China
| | - Ru-Yan Zhang
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, International Joint Research Center for Intelligent Biosensing Technology and Health, Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, College of Chemistry, Central China Normal University, Wuhan 430079, China
| | - Jian Wang
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, International Joint Research Center for Intelligent Biosensing Technology and Health, Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, College of Chemistry, Central China Normal University, Wuhan 430079, China
| | - Shi-Hao Zhou
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, International Joint Research Center for Intelligent Biosensing Technology and Health, Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, College of Chemistry, Central China Normal University, Wuhan 430079, China
| | - Xiao-Qian Peng
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, International Joint Research Center for Intelligent Biosensing Technology and Health, Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, College of Chemistry, Central China Normal University, Wuhan 430079, China
| | - Dong Ding
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, International Joint Research Center for Intelligent Biosensing Technology and Health, Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, College of Chemistry, Central China Normal University, Wuhan 430079, China
| | - Zhi-Ming Zhang
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, International Joint Research Center for Intelligent Biosensing Technology and Health, Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, College of Chemistry, Central China Normal University, Wuhan 430079, China
| | - Hua-Wei Wei
- Jiangsu East-Mab Biomedical Technology Co. Ltd, Nantong 226499, China
| | - Jun Guo
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, International Joint Research Center for Intelligent Biosensing Technology and Health, Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, College of Chemistry, Central China Normal University, Wuhan 430079, China.
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5
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Zheng Q, Chang PV. Shedding Light on Bacterial Physiology with Click Chemistry. Isr J Chem 2023; 63:e202200064. [PMID: 37841997 PMCID: PMC10569449 DOI: 10.1002/ijch.202200064] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Indexed: 11/11/2022]
Abstract
Bacteria constitute a major lifeform on this planet and play numerous roles in ecology, physiology, and human disease. However, conventional methods to probe their activities are limited in their ability to visualize and identify their functions in these diverse settings. In the last two decades, the application of click chemistry to label these microbes has deepened our understanding of bacterial physiology. With the development of a plethora of chemical tools that target many biological molecules, it is possible to track these microorganisms in real-time and at unprecedented resolution. Here, we review click chemistry, including bioorthogonal reactions, and their applications in imaging bacterial glycans, lipids, proteins, and nucleic acids using chemical reporters. We also highlight significant advances that have enabled biological discoveries that have heretofore remained elusive.
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Affiliation(s)
- Qiuyu Zheng
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853
| | - Pamela V Chang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853
- Cornell Center for Immunology, Cornell University, Ithaca, NY 14853
- Cornell Institute of Host-Microbe Interactions and Disease, Cornell University, Ithaca, NY 14853
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6
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de Jong H, Moure MJ, Hartman JEM, Bosman GP, Ong JY, Bardoel BW, Boons G, Wösten MMSM, Wennekes T. Selective Exoenzymatic Labeling of Lipooligosaccharides of Neisseria gonorrhoeae with α2,6-Sialoside Analogues. Chembiochem 2022; 23:e202200340. [PMID: 35877976 PMCID: PMC9804176 DOI: 10.1002/cbic.202200340] [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: 06/14/2022] [Revised: 07/23/2022] [Indexed: 01/05/2023]
Abstract
The interactions between bacteria and their host often rely on recognition processes that involve host or bacterial glycans. Glycoengineering techniques make it possible to modify and study the glycans on the host's eukaryotic cells, but only a few are available for the study of bacterial glycans. Here, we have adapted selective exoenzymatic labeling (SEEL), a chemical reporter strategy, to label the lipooligosaccharides of the bacterial pathogen Neisseria gonorrhoeae, using the recombinant glycosyltransferase ST6Gal1, and three synthetic CMP-sialic acid derivatives. We show that SEEL treatment does not affect cell viability and can introduce an α2,6-linked sialic acid with a reporter group on the lipooligosaccharides by Western blot, flow cytometry and fluorescent microscopy. This new bacterial glycoengineering technique allows for the precise modification, here with α2,6-sialoside derivatives, and direct detection of specific surface glycans on live bacteria, which will aid in further unravelling the precise biological functions of bacterial glycans.
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Affiliation(s)
- Hanna de Jong
- Department of Chemical Biology and Drug Discovery Utrecht Institute for Pharmaceutical Sciences and Bijvoet Center for Biomedical ResearchUtrecht UniversityUniversiteitsweg 993584 CGUtrechtThe Netherlands,Department of Biomolecular Health SciencesUtrecht UniversityYalelaan 13584 CLUtrechtThe Netherlands
| | - Maria J. Moure
- Complex Carbohydrate Research Center and Department of ChemistryUniversity of Georgia315 Riverbend RoadAthensGA 30602USA,Chemical Glycobiology Lab, CIC bioGUNEBasque Research & Technology Alliance (BRTA)Bizkaia Technology Park, Building 80048160DerioSpain
| | - Jet E. M. Hartman
- Department of Chemical Biology and Drug Discovery Utrecht Institute for Pharmaceutical Sciences and Bijvoet Center for Biomedical ResearchUtrecht UniversityUniversiteitsweg 993584 CGUtrechtThe Netherlands
| | - Gerlof P. Bosman
- Department of Chemical Biology and Drug Discovery Utrecht Institute for Pharmaceutical Sciences and Bijvoet Center for Biomedical ResearchUtrecht UniversityUniversiteitsweg 993584 CGUtrechtThe Netherlands
| | - Jun Yang Ong
- Department of Chemical Biology and Drug Discovery Utrecht Institute for Pharmaceutical Sciences and Bijvoet Center for Biomedical ResearchUtrecht UniversityUniversiteitsweg 993584 CGUtrechtThe Netherlands
| | - Bart W. Bardoel
- Department of Medical MicrobiologyUniversity Medical Center UtrechtHeidelberglaan 100 HP G04.6143584 CXUtrechtThe Netherlands
| | - Geert‐Jan Boons
- Department of Chemical Biology and Drug Discovery Utrecht Institute for Pharmaceutical Sciences and Bijvoet Center for Biomedical ResearchUtrecht UniversityUniversiteitsweg 993584 CGUtrechtThe Netherlands,Complex Carbohydrate Research Center and Department of ChemistryUniversity of Georgia315 Riverbend RoadAthensGA 30602USA
| | - Marc M. S. M. Wösten
- Department of Biomolecular Health SciencesUtrecht UniversityYalelaan 13584 CLUtrechtThe Netherlands
| | - Tom Wennekes
- Department of Chemical Biology and Drug Discovery Utrecht Institute for Pharmaceutical Sciences and Bijvoet Center for Biomedical ResearchUtrecht UniversityUniversiteitsweg 993584 CGUtrechtThe Netherlands
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7
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Tyrikos-Ergas T, Gim S, Huang JY, Pinzón Martín S, Varón Silva D, Seeberger PH, Delbianco M. Synthetic phosphoethanolamine-modified oligosaccharides reveal the importance of glycan length and substitution in biofilm-inspired assemblies. Nat Commun 2022; 13:3954. [PMID: 35804023 PMCID: PMC9270332 DOI: 10.1038/s41467-022-31633-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 06/28/2022] [Indexed: 12/18/2022] Open
Abstract
Bacterial biofilm matrices are nanocomposites of proteins and polysaccharides with remarkable mechanical properties. Efforts understanding and tuning the protein component have been extensive, whereas the polysaccharide part remained mostly overlooked. The discovery of phosphoethanolamine (pEtN) modified cellulose in E. coli biofilms revealed that polysaccharide functionalization alters the biofilm properties. To date, the pattern of pEtN cellulose and its mode of interactions with proteins remains elusive. Herein, we report a model system based on synthetic epitomes to explore the role of pEtN in biofilm-inspired assemblies. Nine pEtN-modified oligosaccharides were synthesized with full control over the length, degree and pattern of pEtN substitution. The oligomers were co-assembled with a representative peptide, triggering the formation of fibers in a length dependent manner. We discovered that the pEtN pattern modulates the adhesion of biofilm-inspired matrices, while the peptide component controls its stiffness. Unnatural oligosaccharides tune or disrupt the assembly morphology, revealing interesting targets for polysaccharide engineering to develop tunable bio-inspired materials.
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Affiliation(s)
- Theodore Tyrikos-Ergas
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476, Potsdam, Germany.,Department of Chemistry and Biochemistry, Freie Universität Berlin, Arnimallee 22, 14195, Berlin, Germany
| | - Soeun Gim
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476, Potsdam, Germany.,Department of Chemistry and Biochemistry, Freie Universität Berlin, Arnimallee 22, 14195, Berlin, Germany
| | - Jhih-Yi Huang
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476, Potsdam, Germany.,Department of Chemistry and Biochemistry, Freie Universität Berlin, Arnimallee 22, 14195, Berlin, Germany
| | - Sandra Pinzón Martín
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476, Potsdam, Germany.,Department of Chemistry and Biochemistry, Freie Universität Berlin, Arnimallee 22, 14195, Berlin, Germany
| | - Daniel Varón Silva
- Department of Chemistry and Biochemistry, Freie Universität Berlin, Arnimallee 22, 14195, Berlin, Germany.,Institute of Chemistry and Bioanalytics, School of Life Sciences, University of Applied Sciences and Arts Northwestern Switzerland, Hofackerstrasse 30, 4132, Muttenz, Switzerland
| | - Peter H Seeberger
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476, Potsdam, Germany.,Department of Chemistry and Biochemistry, Freie Universität Berlin, Arnimallee 22, 14195, Berlin, Germany
| | - Martina Delbianco
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476, Potsdam, Germany.
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8
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Jong H, Wösten MMSM, Wennekes T. Sweet impersonators: Molecular mimicry of host glycans by bacteria. Glycobiology 2021; 32:11-22. [PMID: 34939094 PMCID: PMC8881735 DOI: 10.1093/glycob/cwab104] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 09/03/2021] [Accepted: 09/28/2021] [Indexed: 12/02/2022] Open
Abstract
All bacteria display surface-exposed glycans that can play an important role in their interaction with the host and in select cases mimic the glycans found on host cells, an event called molecular or glycan mimicry. In this review, we highlight the key bacteria that display human glycan mimicry and provide an overview of the involved glycan structures. We also discuss the general trends and outstanding questions associated with human glycan mimicry by bacteria. Finally, we provide an overview of several techniques that have emerged from the discipline of chemical glycobiology, which can aid in the study of the composition, variability, interaction and functional role of these mimicking glycans.
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Affiliation(s)
- Hanna Jong
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences and Bijvoet Center for Biomedical Research, Utrecht University, Utrecht, The Netherlands.,Department of Biomolecular Health Sciences, Utrecht University, Utrecht, The Netherlands
| | - Marc M S M Wösten
- Department of Biomolecular Health Sciences, Utrecht University, Utrecht, The Netherlands
| | - Tom Wennekes
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences and Bijvoet Center for Biomedical Research, Utrecht University, Utrecht, The Netherlands
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9
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Luong P, Dube DH. Dismantling the bacterial glycocalyx: Chemical tools to probe, perturb, and image bacterial glycans. Bioorg Med Chem 2021; 42:116268. [PMID: 34130219 DOI: 10.1016/j.bmc.2021.116268] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 05/27/2021] [Accepted: 06/01/2021] [Indexed: 12/20/2022]
Abstract
The bacterial glycocalyx is a quintessential drug target comprised of structurally distinct glycans. Bacterial glycans bear unusual monosaccharide building blocks whose proper construction is critical for bacterial fitness, survival, and colonization in the human host. Despite their appeal as therapeutic targets, bacterial glycans are difficult to study due to the presence of rare bacterial monosaccharides that are linked and modified in atypical manners. Their structural complexity ultimately hampers their analytical characterization. This review highlights recent advances in bacterial chemical glycobiology and focuses on the development of chemical tools to probe, perturb, and image bacterial glycans and their biosynthesis. Current technologies have enabled the study of bacterial glycosylation machinery even in the absence of detailed structural information.
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Affiliation(s)
- Phuong Luong
- Department of Chemistry & Biochemistry, Bowdoin College, 6600 College Station, Brunswick, ME 04011, USA
| | - Danielle H Dube
- Department of Chemistry & Biochemistry, Bowdoin College, 6600 College Station, Brunswick, ME 04011, USA.
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10
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Calabretta PJ, Hodges HL, Kraft MB, Marando VM, Kiessling LL. Bacterial Cell Wall Modification with a Glycolipid Substrate. J Am Chem Soc 2019; 141:9262-9272. [PMID: 31081628 DOI: 10.1021/jacs.9b02290] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Despite the ubiquity and importance of glycans in biology, methods to probe their structures in cells are limited. Mammalian glycans can be modulated using metabolic incorporation, a process in which non-natural sugars are taken up by cells, converted to nucleotide-sugar intermediates, and incorporated into glycans via biosynthetic pathways. These studies have revealed that glycan intermediates can be shunted through multiple pathways, and this complexity can be heightened in bacteria, as they can catabolize diverse glycans. We sought to develop a strategy that probes structures recalcitrant to metabolic incorporation and that complements approaches focused on nucleotide sugars. We reasoned that lipid-linked glycans, which are intermediates directly used in glycan biosynthesis, would offer an alternative. We generated synthetic arabinofuranosyl phospholipids to test this strategy in Corynebacterium glutamicum and Mycobacterium smegmatis, organisms that serve as models of Mycobacterium tuberculosis. Using a C. glutamicum mutant that lacks arabinan, we identified synthetic glycosyl donors whose addition restores cell wall arabinan, demonstrating that non-natural glycolipids can serve as biosynthetic intermediates and function in chemical complementation. The addition of an isotopically labeled glycan substrate facilitated cell wall characterization by NMR. Structural analysis revealed that all five known arabinofuranosyl transferases could process the exogenous lipid-linked sugar donor, allowing for the full recovery of the cell envelope. The lipid-based probe could also rescue wild-type cells treated with an inhibitor of cell wall biosynthesis. Our data indicate that surrogates of natural lipid-linked glycans can intervene in the cell's traditional workflow, indicating that biosynthetic incorporation is a powerful strategy for probing glycan structure and function.
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Affiliation(s)
- Phillip J Calabretta
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | | | | | - Victoria M Marando
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Laura L Kiessling
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
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11
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Bi X, Yin J, Chen Guanbang A, Liu CF. Chemical and Enzymatic Strategies for Bacterial and Mammalian Cell Surface Engineering. Chemistry 2018; 24:8042-8050. [DOI: 10.1002/chem.201705049] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Indexed: 12/11/2022]
Affiliation(s)
- Xiaobao Bi
- School of Biological Sciences; Nanyang Technological University; 60 Nanyang Drive Singapore 637551 Singapore
| | - Juan Yin
- Current address: Program in Neuroscience and behavioural disorders; Duke-NUS Medical School; 8 College Road Singapore 169857 Singapore
| | - Ashley Chen Guanbang
- School of Biological Sciences; Nanyang Technological University; 60 Nanyang Drive Singapore 637551 Singapore
| | - Chuan-Fa Liu
- School of Biological Sciences; Nanyang Technological University; 60 Nanyang Drive Singapore 637551 Singapore
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12
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Huang LL, Liu K, Zhang Q, Xu J, Zhao D, Zhu H, Xie HY. Integrating Two Efficient and Specific Bioorthogonal Ligation Reactions with Natural Metabolic Incorporation in One Cell for Virus Dual Labeling. Anal Chem 2017; 89:11620-11627. [DOI: 10.1021/acs.analchem.7b03043] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Li-Li Huang
- School of Life Science, Beijing Institute of Technology, Beijing 100081, China
| | - Kejiang Liu
- School of Life Science, Beijing Institute of Technology, Beijing 100081, China
| | - Qianmei Zhang
- School of Life Science, Beijing Institute of Technology, Beijing 100081, China
| | - Jin Xu
- School of Life Science, Beijing Institute of Technology, Beijing 100081, China
| | - Dongxu Zhao
- School of Life Science, Beijing Institute of Technology, Beijing 100081, China
| | - Houshun Zhu
- School of Life Science, Beijing Institute of Technology, Beijing 100081, China
| | - Hai-Yan Xie
- School of Life Science, Beijing Institute of Technology, Beijing 100081, China
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13
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Sminia TJ, Zuilhof H, Wennekes T. Getting a grip on glycans: A current overview of the metabolic oligosaccharide engineering toolbox. Carbohydr Res 2016; 435:121-141. [PMID: 27750120 DOI: 10.1016/j.carres.2016.09.007] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2016] [Revised: 09/14/2016] [Accepted: 09/15/2016] [Indexed: 12/16/2022]
Abstract
This review discusses the advances in metabolic oligosaccharide engineering (MOE) from 2010 to 2016 with a focus on the structure, preparation, and reactivity of its chemical probes. A brief historical overview of MOE is followed by a comprehensive overview of the chemical probes currently available in the MOE molecular toolbox and the bioconjugation techniques they enable. The final part of the review focusses on the synthesis of a selection of probes and finishes with an outlook on recent and potential upcoming advances in the field of MOE.
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Affiliation(s)
- Tjerk J Sminia
- Laboratory of Organic Chemistry, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Han Zuilhof
- Laboratory of Organic Chemistry, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Tom Wennekes
- Laboratory of Organic Chemistry, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands; Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences and Bijvoet Center for Biomolecular Research, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.
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14
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Wratil PR, Horstkorte R, Reutter W. Metabolic Glycoengineering with N-Acyl Side Chain Modified Mannosamines. Angew Chem Int Ed Engl 2016; 55:9482-512. [PMID: 27435524 DOI: 10.1002/anie.201601123] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Indexed: 12/14/2022]
Abstract
In metabolic glycoengineering (MGE), cells or animals are treated with unnatural derivatives of monosaccharides. After entering the cytosol, these sugar analogues are metabolized and subsequently expressed on newly synthesized glycoconjugates. The feasibility of MGE was first discovered for sialylated glycans, by using N-acyl-modified mannosamines as precursor molecules for unnatural sialic acids. Prerequisite is the promiscuity of the enzymes of the Roseman-Warren biosynthetic pathway. These enzymes were shown to tolerate specific modifications of the N-acyl side chain of mannosamine analogues, for example, elongation by one or more methylene groups (aliphatic modifications) or by insertion of reactive groups (bioorthogonal modifications). Unnatural sialic acids are incorporated into glycoconjugates of cells and organs. MGE has intriguing biological consequences for treated cells (aliphatic MGE) and offers the opportunity to visualize the topography and dynamics of sialylated glycans in vitro, ex vivo, and in vivo (bioorthogonal MGE).
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Affiliation(s)
- Paul R Wratil
- Institut für Laboratoriumsmedizin, Klinische Chemie und Pathobiochemie, Charité-Universitätsmedizin Berlin, Arnimallee 22, 14195, Berlin, Germany.
| | - Rüdiger Horstkorte
- Institut für Physiologische Chemie, Martin-Luther-Universität Halle-Wittenberg, Hollystrasse 1, 06114, Halle, Germany.
| | - Werner Reutter
- Institut für Laboratoriumsmedizin, Klinische Chemie und Pathobiochemie, Charité-Universitätsmedizin Berlin, Arnimallee 22, 14195, Berlin, Germany
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15
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Wratil PR, Horstkorte R, Reutter W. Metabolisches Glykoengineering mitN-Acyl-Seiten- ketten-modifizierten Mannosaminen. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201601123] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Paul R. Wratil
- Institut für Laboratoriumsmedizin, Klinische Chemie und Pathobiochemie; Charité - Universitätsmedizin Berlin; Arnimallee 22 14195 Berlin Deutschland
| | - Rüdiger Horstkorte
- Institut für Physiologische Chemie; Martin-Luther-Universität Halle-Wittenberg; Hollystraße 1 06114 Halle Deutschland
| | - Werner Reutter
- Institut für Laboratoriumsmedizin, Klinische Chemie und Pathobiochemie; Charité - Universitätsmedizin Berlin; Arnimallee 22 14195 Berlin Deutschland
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16
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Li Z, Liu Z, Chen Z, Ju E, Li W, Ren J, Qu X. Bioorthogonal chemistry for selective recognition, separation and killing bacteria over mammalian cells. Chem Commun (Camb) 2016; 52:3482-5. [DOI: 10.1039/c5cc10625g] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
We report a new strategy for selective recognition, separation and killing bacteria using metabolic engineering and bioorthogonal chemistry.
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Affiliation(s)
- Zhenhua Li
- Laboratory of Chemical Biology and State Key laboratory of Rare Earth Resources Utilization
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun 130022
- China
| | - Zhen Liu
- Laboratory of Chemical Biology and State Key laboratory of Rare Earth Resources Utilization
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun 130022
- China
| | - Zhaowei Chen
- Laboratory of Chemical Biology and State Key laboratory of Rare Earth Resources Utilization
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun 130022
- China
| | - Enguo Ju
- Laboratory of Chemical Biology and State Key laboratory of Rare Earth Resources Utilization
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun 130022
- China
| | - Wei Li
- Laboratory of Chemical Biology and State Key laboratory of Rare Earth Resources Utilization
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun 130022
- China
| | - Jinsong Ren
- Laboratory of Chemical Biology and State Key laboratory of Rare Earth Resources Utilization
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun 130022
- China
| | - Xiaogang Qu
- Laboratory of Chemical Biology and State Key laboratory of Rare Earth Resources Utilization
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun 130022
- China
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17
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Saeui CT, Urias E, Liu L, Mathew MP, Yarema KJ. Metabolic glycoengineering bacteria for therapeutic, recombinant protein, and metabolite production applications. Glycoconj J 2015; 32:425-41. [PMID: 25931032 DOI: 10.1007/s10719-015-9583-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 03/16/2015] [Accepted: 03/19/2015] [Indexed: 12/12/2022]
Abstract
Metabolic glycoengineering is a specialization of metabolic engineering that focuses on using small molecule metabolites to manipulate biosynthetic pathways responsible for oligosaccharide and glycoconjugate production. As outlined in this article, this technique has blossomed in mammalian systems over the past three decades but has made only modest progress in prokaryotes. Nevertheless, a sufficient foundation now exists to support several important applications of metabolic glycoengineering in bacteria based on methods to preferentially direct metabolic intermediates into pathways involved in lipopolysaccharide, peptidoglycan, teichoic acid, or capsule polysaccharide production. An overview of current applications and future prospects for this technology are provided in this report.
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Affiliation(s)
- Christopher T Saeui
- Department of Biomedical Engineering and the Translational Tissue Engineering Center, The Johns Hopkins University, Baltimore, MD, USA
| | - Esteban Urias
- Department of Biomedical Engineering and the Translational Tissue Engineering Center, The Johns Hopkins University, Baltimore, MD, USA
| | - Lingshu Liu
- Department of Biomedical Engineering and the Translational Tissue Engineering Center, The Johns Hopkins University, Baltimore, MD, USA
| | - Mohit P Mathew
- Department of Biomedical Engineering and the Translational Tissue Engineering Center, The Johns Hopkins University, Baltimore, MD, USA
| | - Kevin J Yarema
- Department of Biomedical Engineering and the Translational Tissue Engineering Center, The Johns Hopkins University, Baltimore, MD, USA.
- Translational Tissue Engineering Center, The Johns Hopkins University, 5029 Robert H. & Clarice Smith Building, 400 North Broadway, Baltimore, MD, 21231, USA.
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18
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Zhou Z, Liao G, Stepanovs S, Guo Z. Quantifying the Efficiency of N-Phenyl-D-mannosamine to Metabolically Engineer Sialic Acid on Cancer Cell Surface. J Carbohydr Chem 2014; 33:395-407. [PMID: 25400325 PMCID: PMC4228960 DOI: 10.1080/07328303.2014.933483] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A convenient method was developed for the quantification of sialic acids expressed by cells and used to analyze the efficiency of N-phenylacetyl-D-mannosamine (ManNPhAc) to metabolically glycoengineer SKMEL-28 cancer cell. For this purpose, ManNPhAc-cultured cells were treated with 2M acetic acid to release sialic acids, and the products were treated with 1,2-diamino-4,5-methylenedioxybenzene to form the corresponding derivatives that had strong UV absorptions. The reaction mixture was then applied to HPLC-UV analysis to determine the amounts and the ratios of natural sialic acid and its unnatural analog. It was confirmed that after incubation with ManNPhAc SKMEL-28 cell was effectively glycoengineered to express a significant amount of unnatural sialic acid.
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Affiliation(s)
- Zhifang Zhou
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA
| | - Guochao Liao
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA
| | - Sergejs Stepanovs
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA
| | - Zhongwu Guo
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA
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19
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Tra VN, Dube DH. Glycans in pathogenic bacteria--potential for targeted covalent therapeutics and imaging agents. Chem Commun (Camb) 2014; 50:4659-73. [PMID: 24647371 PMCID: PMC4049282 DOI: 10.1039/c4cc00660g] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A substantial obstacle to the existing treatment of bacterial diseases is the lack of specific probes that can be used to diagnose and treat pathogenic bacteria in a selective manner while leaving the microbiome largely intact. To tackle this problem, there is an urgent need to develop pathogen-specific therapeutics and diagnostics. Here, we describe recent evidence that indicates distinctive glycans found exclusively on pathogenic bacteria could form the basis of targeted therapeutic and diagnostic strategies. In particular, we highlight the use of metabolic oligosaccharide engineering to covalently deliver therapeutics and imaging agents to bacterial glycans.
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Affiliation(s)
- Van N Tra
- Bowdoin College, Department of Chemistry & Biochemistry, Brunswick, Maine, USA.
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20
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Abstract
Over the past three decades, a powerful array of techniques has been developed for expressing heterologous proteins and saccharides on the surface of bacteria. Surface-engineered bacteria, in turn, have proven useful in a variety of settings, including high-throughput screening, biofuel production, and vaccinology. In this chapter, we provide a comprehensive review of methods for displaying polypeptides and sugars on the bacterial cell surface, and discuss the many innovative applications these methods have found to date. While already an important biotechnological tool, we believe bacterial surface display may be further improved through integration with emerging methodology in other fields, such as protein engineering and synthetic chemistry. Ultimately, we envision bacterial display becoming a multidisciplinary platform with the potential to transform basic and applied research in bacteriology, biotechnology, and biomedicine.
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21
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Fluorogenic sialic acid glycosides for quantification of sialidase activity upon unnatural substrates. Bioorg Med Chem Lett 2013; 23:3406-10. [PMID: 23639536 DOI: 10.1016/j.bmcl.2013.03.076] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Revised: 03/13/2013] [Accepted: 03/20/2013] [Indexed: 11/23/2022]
Abstract
Herein we report the synthesis of N-acetyl neuraminic acid derivatives as 4-methylumbelliferyl glycosides and their use in fluorometrically quantifying human and bacterial sialidase activity and substrate specificities. We found that sialidases in the human promyelocytic leukemic cell line HL60 were able to cleave sialic acid substrates with fluorinated C-5 modifications, in some cases to a greater degree than the natural N-acetyl functionality. Human sialidases isoforms were also able to cleave unnatural substrates with bulky and hydrophobic C-5 modifications. In contrast, we found that a bacterial sialidase isolated from Clostridium perfringens to be less tolerant of sialic acid derivatization at this position, with virtually no cleavage of these glycosides observed. From our results, we conclude that human sialidase activity is a significant factor in sialic acid metabolic glycoengineering efforts utilizing unnatural sialic acid derivatives. Our fluorogenic probes have enabled further understanding of the activities and substrate specificities of human sialidases in a cellular context.
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22
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Kaewsapsak P, Esonu O, Dube DH. Recruiting the host's immune system to target Helicobacter pylori's surface glycans. Chembiochem 2013; 14:721-6. [PMID: 23512824 DOI: 10.1002/cbic.201300006] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Indexed: 01/01/2023]
Abstract
Due to the increased prevalence of bacterial strains that are resistant to existing antibiotics, there is an urgent need for new antibacterial strategies. Bacterial glycans are an attractive target for new treatments, as they are frequently linked to pathogenesis and contain distinctive structures that are absent in humans. We set out to develop a novel targeting strategy based on surface glycans present on the gastric pathogen Helicobacter pylori (Hp). In this study, metabolic labeling of bacterial glycans with an azide-containing sugar allowed selective delivery of immune stimulants to azide-covered Hp. We established that Hp's surface glycans are labeled by treatment with the metabolic substrate peracetylated N-azidoacetylglucosamine (Ac4 GlcNAz). By contrast, mammalian cells treated with Ac4 GlcNAz exhibited no incorporation of the chemical label within extracellular glycans. We further demonstrated that the Staudinger ligation between azides and phosphines proceeds under acidic conditions with only a small loss of efficiency. We then targeted azide-covered Hp with phosphines conjugated to the immune stimulant 2,4-dinitrophenyl (DNP), a compound capable of directing a host immune response against these cells. Finally, we report that immune effector cells catalyze selective damage in vitro to DNP-covered Hp in the presence of anti-DNP antibodies. The technology reported herein represents a novel strategy to target Hp based on its glycans.
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Affiliation(s)
- Pornchai Kaewsapsak
- Department of Chemistry & Biochemistry, Bowdoin College, 6600 College Station, Brunswick, ME 04011, USA
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23
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Gautam S, Gniadek TJ, Kim T, Spiegel DA. Exterior design: strategies for redecorating the bacterial surface with small molecules. Trends Biotechnol 2013; 31:258-67. [PMID: 23490213 DOI: 10.1016/j.tibtech.2013.01.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Revised: 01/18/2013] [Accepted: 01/18/2013] [Indexed: 02/02/2023]
Abstract
Recombinant techniques for expressing heterologous proteins and sugars on the surface of bacteria have been known since the 1980s, and have proven useful in a variety of settings from biocatalysis to vaccinology. The past decade has also seen the emergence of novel methods that allow modification of bacterial surfaces with small non-biological compounds. Such technologies enable researchers to harness the unique properties of synthetic materials on a live bacterial platform, opening the door to an exciting new set of applications. Here we review strategies for bacterial surface display and describe how they have been applied thus far. We believe that chemical surface display holds great potential for advancing research in basic bacteriology and applied fields of biotechnology and biomedicine.
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Affiliation(s)
- Samir Gautam
- Department of Cell Biology, Yale School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
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24
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Abstract
Glycosylation is an abundant post-translational modification that alters the fate and function of its substrate proteins. To aid in understanding the significance of protein glycosylation, identification of target proteins is key. As with all proteomics experiments, mass spectrometry has been established as the desired method for substrate identification. However, these approaches require selective enrichment and purification of modified proteins. Chemical reporters in combination with bioorthogonal reactions have emerged as robust tools for identifying post-translational modifications including glycosylation. We provide here a method for the use of bioorthogonal chemical reporters for isolation and identification of glycosylated proteins. More specifically, this protocol is a representative procedure from our own work using an alkyne-bearing O-GlcNAc chemical reporter (GlcNAlk) and a chemically cleavable azido-azo-biotin probe for the identification of O-GlcNAc-modified proteins.
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Affiliation(s)
- Balyn W Zaro
- Department of Chemistry, University of Southern California, Los Angeles, CA, USA
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25
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Sialylation of lipooligosaccharides is dispensable for the virulence of Haemophilus ducreyi in humans. Infect Immun 2011; 80:679-87. [PMID: 22144477 DOI: 10.1128/iai.05826-11] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Sialylated glycoconjugates on the surfaces of mammalian cells play important roles in intercellular communication and self-recognition. The sialic acid preferentially expressed in human tissues is N-acetylneuraminic acid (Neu5Ac). In a process called molecular mimicry, many bacterial pathogens decorate their cell surface glycolipids with Neu5Ac. Incorporation of Neu5Ac into bacterial glycolipids promotes bacterial interactions with host cell receptors called Siglecs. These interactions affect bacterial adherence, resistance to serum killing and phagocytosis, and innate immune responses. Haemophilus ducreyi, the etiologic agent of chancroid, expresses lipooligosaccharides (LOS) that are highly sialylated. However, an H. ducreyi sialyltransferase (lst) mutant, whose LOS contain reduced levels of Neu5Ac, is fully virulent in human volunteers. Recently, a second sialyltransferase gene (Hd0053) was discovered in H. ducreyi, raising the possibility that Hd0053 compensated for the loss of lst during human infection. CMP-Neu5Ac is the obligate nucleotide sugar donor for all bacterial sialyltransferases; LOS derived from an H. ducreyi CMP-Neu5Ac synthetase (neuA) mutant has no detectable Neu5Ac. Here, we compared an H. ducreyi neuA mutant to its wild-type parent in several models of pathogenesis. In human inoculation experiments, the neuA mutant formed papules and pustules at rates that were no different than those of its parent. When grown in media with and without Neu5Ac supplementation, the neuA mutant and its parent had similar phenotypes in bactericidal, macrophage uptake, and dendritic cell activation assays. Although we cannot preclude a contribution of LOS sialylation to ulcerative disease, these data strongly suggest that sialylation of LOS is dispensable for H. ducreyi pathogenesis in humans.
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26
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Dube DH, Champasa K, Wang B. Chemical tools to discover and target bacterial glycoproteins. Chem Commun (Camb) 2011; 47:87-101. [DOI: 10.1039/c0cc01557a] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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27
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Nelson JW, Chamessian AG, McEnaney PJ, Murelli RP, Kazmiercak BI, Spiegel DA, Spiegel DA. A biosynthetic strategy for re-engineering the Staphylococcus aureus cell wall with non-native small molecules. ACS Chem Biol 2010; 5:1147-55. [PMID: 20923200 DOI: 10.1021/cb100195d] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Staphylococcus aureus (S. aureus) is a Gram-positive bacterial pathogen that has emerged as a major public health threat. Here we report that the cell wall of S. aureus can be covalently re-engineered to contain non-native small molecules. This process makes use of endogenous levels of the bacterial enzyme sortase A (SrtA), which ordinarily functions to incorporate proteins into the bacterial cell wall. Thus, incubation of wild-type bacteria with rationally designed SrtA substrates results in covalent incorporation of functional molecular handles (fluorescein, biotin, and azide) into cell wall peptidoglycan. These conclusions are supported by data obtained through a variety of experimental techniques (epifluorescence and electron microscopy, biochemical extraction, and mass spectrometry), and cell-wall-incorporated azide was exploited as a chemical handle to perform an azide-alkyne cycloaddition reaction on the bacterial cell surface. This report represents the first example of cell wall engineering of S. aureus or any other pathogenic Gram-positive bacteria and has the potential for widespread utility.
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Affiliation(s)
- James W. Nelson
- Department of Chemistry, Yale University, New Haven, Connecticut 06520
| | | | | | - Ryan P. Murelli
- Department of Chemistry, Yale University, New Haven, Connecticut 06520
| | - Barbara I. Kazmiercak
- Department of Medicine (Infectious Diseases), Section of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut 06520
| | - David A. Spiegel
- Department of Chemistry, Yale University, New Haven, Connecticut 06520
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28
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Dafik L, d'Alarcao M, Kumar K. Modulation of cellular adhesion by glycoengineering. J Med Chem 2010; 53:4277-84. [PMID: 20438083 DOI: 10.1021/jm100374g] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Aberrant glycosylation of lipid and protein molecules on cellular surfaces is responsible for many of the pathophysiological events in tumor progression and metastasis. Sialic acids in particular, are overexpressed on the glycocalyx of malignant tumor cells and sialic acid-mediated cell adhesion is required for metastasis. We report here that replacement of sialic acids on cell surfaces with fluorinated congeners dramatically decreases cell adhesion to E- and P-selectin-coated surfaces. Comparison of adhesion of fluorinated cells with those modified with nonfluorinated analogues suggests that both reduce binding of the modified sialosides to their cognate lectins to a similar extent on a per molecule basis. The overall reduction in cell adhesion results from greater cell surface presentation of the fluorinated congeners. This work suggests an avenue for inhibition of metastasis by administration of small molecules and concomitant noninvasive imaging of tumor cells by (19)F MRI before they are visible by other means.
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Affiliation(s)
- Laila Dafik
- Department of Chemistry, Tufts University, Medford, Massachusetts 02155, USA
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29
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Homann A, Qamar RU, Serim S, Dersch P, Seibel J. Bioorthogonal metabolic glycoengineering of human larynx carcinoma (HEp-2) cells targeting sialic acid. Beilstein J Org Chem 2010; 6:24. [PMID: 20502611 PMCID: PMC2874417 DOI: 10.3762/bjoc.6.24] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Accepted: 02/17/2010] [Indexed: 01/14/2023] Open
Abstract
Sialic acids are located at the termini of mammalian cell-surface glycostructures, which participate in essential interaction processes including adhesion of pathogens prior to infection and immunogenicity. Here we present the synthesis and bioorthogonal metabolic incorporation of the sialic acid analogue N-(1-oxohex-5-ynyl)neuraminic acid (Neu5Hex) into the cell-surface glycocalyx of a human larynx carcinoma cell line (HEp-2) and its fluorescence labelling by click chemistry.
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Affiliation(s)
- Arne Homann
- University of Würzburg, Department of Organic Chemistry, Am Hubland, 97074 Würzburg, Germany
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30
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Du J, Meledeo MA, Wang Z, Khanna HS, Paruchuri VDP, Yarema KJ. Metabolic glycoengineering: sialic acid and beyond. Glycobiology 2009; 19:1382-401. [PMID: 19675091 DOI: 10.1093/glycob/cwp115] [Citation(s) in RCA: 229] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
This report provides a perspective on metabolic glycoengineering methodology developed over the past two decades that allows natural sialic acids to be replaced with chemical variants in living cells and animals. Examples are given demonstrating how this technology provides the glycoscientist with chemical tools that are beginning to reproduce Mother Nature's control over complex biological systems - such as the human brain - through subtle modifications in sialic acid chemistry. Several metabolic substrates (e.g., ManNAc, Neu5Ac, and CMP-Neu5Ac analogs) can be used to feed flux into the sialic acid biosynthetic pathway resulting in numerous - and sometime quite unexpected - biological repercussions upon nonnatural sialoside display in cellular glycans. Once on the cell surface, ketone-, azide-, thiol-, or alkyne-modified glycans can be transformed with numerous ligands via bioorthogonal chemoselective ligation reactions, greatly increasing the versatility and potential application of this technology. Recently, sialic acid glycoengineering methodology has been extended to other pathways with analog incorporation now possible in surface-displayed GalNAc and fucose residues as well as nucleocytoplasmic O-GlcNAc-modified proteins. Finally, recent efforts to increase the "druggability" of sugar analogs used in metabolic glycoengineering, which have resulted in unanticipated "scaffold-dependent" activities, are summarized.
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Affiliation(s)
- Jian Du
- Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, MD 21218, USA
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31
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Harvey DJ. Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update for 2003-2004. MASS SPECTROMETRY REVIEWS 2009; 28:273-361. [PMID: 18825656 PMCID: PMC7168468 DOI: 10.1002/mas.20192] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2008] [Revised: 07/07/2008] [Accepted: 07/07/2008] [Indexed: 05/13/2023]
Abstract
This review is the third update of the original review, published in 1999, on the application of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings the topic to the end of 2004. Both fundamental studies and applications are covered. The main topics include methodological developments, matrices, fragmentation of carbohydrates and applications to large polymeric carbohydrates from plants, glycans from glycoproteins and those from various glycolipids. Other topics include the use of MALDI MS to study enzymes related to carbohydrate biosynthesis and degradation, its use in industrial processes, particularly biopharmaceuticals and its use to monitor products of chemical synthesis where glycodendrimers and carbohydrate-protein complexes are highlighted.
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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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Remodeling bacterial polysaccharides by metabolic pathway engineering. Proc Natl Acad Sci U S A 2009; 106:4207-12. [PMID: 19251666 DOI: 10.1073/pnas.0812432106] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Introducing structural modifications into biomolecules represents a powerful approach to dissect their functions and roles in biological processes. Bacterial polysaccharides, despite their rich structural information and essential roles in bacterium-host interactions and bacterial virulence, have largely been unexplored for in vivo structural modifications. In this study, we demonstrate the incorporation of a panel of monosaccharide analogs into bacterial polysaccharides in a highly homogenous manner via metabolic engineering of a promiscuous sugar nucleotide biosynthetic pathway. In addition, the bioorthorgonal functional groups metabolically incorporated were exploited for cell surface labeling using in vitro selective chemical ligation reactions. In summary, our study presents a general, facile and effective approach for in vivo generation of novel tailor-made bacterial polysaccharides.
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McLendon MK, Schilling B, Hunt JR, Apicella MA, Gibson BW. Identification of LpxL, a late acyltransferase of Francisella tularensis. Infect Immun 2007; 75:5518-31. [PMID: 17724076 PMCID: PMC2168286 DOI: 10.1128/iai.01288-06] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lipopolysaccharide (LPS) is a major component of the outer membrane of gram-negative bacteria, and the lipid A region of LPS mediates stimulation of the immune system in a structure-dependent manner. Unlike the LPS of many other gram-negative bacteria, the LPS of Francisella tularensis isolated from in vitro cultures is not proinflammatory. This observed lack of proinflammatory prowess may reflect structural features of the lipid A, such as the number and length of the acyl chains and the single-phosphate group. To better understand this phenotype, we have begun to elucidate LPS biosynthesis in F. tularensis. We present complementation, mutational, and chemical data demonstrating that F. tularensis FTT0232c encodes a functional late acyltransferase enzyme with specificity similar to that of the Escherichia coli LpxL ortholog. Expression of this late acyltransferase complemented the temperature-sensitive and hypoacylated lipid A phenotypes of an E. coli lpxL mutant, expression of FTT0232c is increased during intracellular growth relative to that during in vitro growth, and finally, LPS obtained from a mutant of F. tularensis lacking FTT0232c showed an abundant triacyl lipid A species after mass spectrometric analysis, consistent with the loss of an LpxL late acyltransferase.
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Affiliation(s)
- Molly K McLendon
- Department of Microbiology and Inflammation Program, University of Iowa, Iowa City, Iowa, USA
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Campbell CT, Sampathkumar SG, Yarema KJ. Metabolic oligosaccharide engineering: perspectives, applications, and future directions. MOLECULAR BIOSYSTEMS 2007; 3:187-94. [PMID: 17308665 DOI: 10.1039/b614939c] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Many adhesion and signaling molecules critical for development, as well as surface markers implicated in diseases ranging from cancer to influenza, contain oligosaccharides that modify their functions. Inside a cell, complex glycosylation pathways assemble these oligosaccharides and attach them to proteins and lipids as they traffic to the cell surface. Until recently, practical technologies to manipulate glycosylation have lagged unlike the molecular biologic and genetic methods available to intervene in nucleic acid and protein biochemistry; now, metabolic oligosaccharide engineering shows promise for manipulating glycosylation. In this methodology, exogenously-supplied non-natural sugars intercept biosynthetic pathways and exploit the remarkable ability of many of the enzymes involved in glycosylation to process metabolites with slightly altered chemical structures. To date, non-natural forms of sialic acid, GalNAc, GlcNAc, and fucose have been incorporated into glycoconjugates that appear on the cell surface; in addition O-GlcNAc protein modification involved in intracellular signaling has been tagged with modified forms of this sugar. Reactive functional groups, including ketones, azides, and thiols, have been incorporated into glycoconjugates and thereby provide chemical 'tags' that can be used for diverse purposes ranging from drug delivery to new modes of carbohydrate-based cell adhesion that can be used to control stem cell destiny. Finally, strategies for further engineering non-natural sugars to improve their pharmacological properties and provide complementary biological activities, such as addition of short chain fatty acids, are discussed in this article.
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Affiliation(s)
- Christopher T Campbell
- Department of Biomedical Engineering, The Johns Hopkins University, Clark Hall 106A, Baltimore, MD 21218, USA
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Abstract
Information contained in the mammalian glycome is decoded by glycan-binding proteins (GBPs) that mediate diverse functions including host-pathogen interactions, cell trafficking and transmembrane signaling. Although information on the biological roles of GBPs is rapidly expanding, challenges remain in identifying the glycan ligands and their impact on GBP function. Protein-glycan interactions are typically low affinity, requiring multivalent interactions to achieve a biological effect. Though many glycoproteins can carry the glycan structure recognized by the GBP, other factors, such as recognition of protein epitopes and microdomain localization, may restrict which glycoproteins are functional ligands in situ. Recent advances in development of glycan arrays, synthesis of multivalent glycan ligands, bioengineering of cell-surface glycans and glycomics databases are providing new tools to identify the ligands of GBPs and to elucidate the mechanisms by which they participate in GBP function.
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Affiliation(s)
- James C Paulson
- Department of Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA.
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Chefalo P, Pan Y, Nagy N, Guo Z, Harding CV. Efficient metabolic engineering of GM3 on tumor cells by N-phenylacetyl-D-mannosamine. Biochemistry 2006; 45:3733-9. [PMID: 16533056 PMCID: PMC2531244 DOI: 10.1021/bi052161r] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Abnormal carbohydrates expressed on tumor cells, which are termed tumor-associated carbohydrate antigens (TACAs), are potential targets for the development of cancer vaccines. However, immune tolerance to TACAs has severely hindered progress in this area. To overcome this problem, we have developed a novel immunotherapeutic strategy based on synthetic cancer vaccines and metabolic engineering of TACAs on tumor cells. One critical step of this new strategy is metabolic engineering of cancer, namely, to induce expression of an artificial form of a TACA by supplying tumors with an artificial monosaccharide precursor. To identify the proper precursor for this application, N-propionyl, N-butanoyl, N-isobutanoyl, and N-phenylacetyl derivatives of d-mannosamine were synthesized, and their efficiency as biosynthetic precursors in modifying sialic acid and inducing expression of modified forms of GM3 antigen on tumor cells was investigated. For this purpose, tumor cells were incubated with different N-acyl-d-mannosamines, and modified forms of GM3 expressed on tumor cells were analyzed by flow cytometry using antigen-specific antisera. N-Phenylacetyl-d-mannosamine was efficiently incorporated in a time- and dose-dependent manner to bioengineer GM3 expression by several tumor cell lines, including K562, SKMEL-28, and B16-F0. Moreover, these tumor cell lines also exhibited ManPAc-dependent sensitivity to cytotoxicity mediated by anti-PAcGM3 immune serum and complement. These results provide an important validation for this novel therapeutic strategy. Because N-phenylacetyl GM3-protein conjugates are particularly immunogenic, the combination of an N-phenylacetyl GM3 conjugate vaccine with systemic N-phenylacetyl-d-mannosamine treatment is a promising immunotherapy for future development and application to melanoma and other GM3-bearing tumors.
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Affiliation(s)
- Peter Chefalo
- Department of Pathology and Comprehensive Cancer Center, Case Western Reserve University, Cleveland, Ohio 44106, USA
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Post DMB, Mungur R, Gibson BW, Munson RS. Identification of a novel sialic acid transporter in Haemophilus ducreyi. Infect Immun 2005; 73:6727-35. [PMID: 16177350 PMCID: PMC1230923 DOI: 10.1128/iai.73.10.6727-6735.2005] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Haemophilus ducreyi, the causative agent of chancroid, produces a lipooligosaccharide (LOS) which terminates in N-acetyllactosamine. This glycoform can be further extended by the addition of a single sialic acid residue to the terminal galactose moiety. H. ducreyi does not synthesize sialic acid, which must be acquired from the host during infection or from the culture medium when the bacteria are grown in vitro. However, H. ducreyi does not have genes that are highly homologous to the genes encoding known bacterial sialic acid transporters. In this study, we identified the sialic acid transporter by screening strains in a library of random transposon mutants for those mutants that were unable to add sialic acid to N-acetyllactosamine-containing LOS. Mutants that reacted with the monoclonal antibody 3F11, which recognizes the terminal lactosamine structure, and lacked reactivity with the lectin Maackia amurensis agglutinin, which recognizes alpha2,3-linked sialic acid, were further characterized to demonstrate that they produced a N-acetyllactosamine-containing LOS by silver-stained sodium dodecyl sulfate-polyacrylamide gel electrophoresis and mass spectrometric analyses. The genes interrupted in these mutants were mapped to a four-gene cluster with similarity to genes encoding bacterial ABC transporters. Uptake assays using radiolabeled sialic acid confirmed that the mutants were unable to transport sialic acid. This study is the first report of bacteria using an ABC transporter for sialic acid uptake.
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Nguyen DH, Tangvoranuntakul P, Varki A. Effects of Natural Human Antibodies against a Nonhuman Sialic Acid That Metabolically Incorporates into Activated and Malignant Immune Cells. THE JOURNAL OF IMMUNOLOGY 2005; 175:228-36. [PMID: 15972653 DOI: 10.4049/jimmunol.175.1.228] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Humans are genetically incapable of producing the mammalian sialic acid N-glycolylneuraminic acid (Neu5Gc), due to an inactivating mutation in the enzyme synthesizing it. Despite this, human cells and tissues appear capable of metabolically incorporating Neu5Gc from exogenous sources, including dietary red meat and dairy products. All normal humans studied are now shown to have circulating Abs against Neu5Gc, with marked differences in isotype levels. The question arises whether such Abs can adversely affect Neu5Gc-expressing human cells or tissues. In this study, we show that although normal human PBMC do not incorporate Neu5Gc during in vitro incubation, activated T cells do. Primary human leukemia cells and human leukemic cell lines are even more efficient at incorporation. Human sera containing naturally high levels of anti-Neu5Gc IgG Abs (hereafter abbreviated GcIg) deposited complement on Neu5Gc-expressing leukemic cells and activated T cells, but not on normal cells. The binding of GcIg resulted in complement-mediated cytotoxicity, which was inhibited by heat inactivation. Low anti-Neu5Gc IgG-containing human sera did not mediate any of these effects. Mixed killing assays confirmed the 15-fold selective killing of leukemic cells over PBMC by GcIg following Neu5Gc feeding. This approach could potentially serve as novel way to target malignant cells for death in vivo using either natural Abs or anti-Neu5Gc Abs prepared for this purpose. Further studies are needed to determine whether deposition of natural GcIg and complement can also target healthy proliferating immune cells for death in vivo following incorporation of dietary Neu5Gc.
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Affiliation(s)
- Dzung H Nguyen
- Glycobiology Research and Training Center, and Department of Medicine, University of California at San Diego, La Jolla, CA 92093, USA
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Luchansky SJ, Hang HC, Saxon E, Grunwell JR, Yu C, Dube DH, Bertozzi CR. Constructing azide-labeled cell surfaces using polysaccharide biosynthetic pathways. Methods Enzymol 2003; 362:249-72. [PMID: 12968369 DOI: 10.1016/s0076-6879(03)01018-8] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Sarah J Luchansky
- Department of Chemistry, University of California, Berkeley, California 94720, USA
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