1
|
Ghosh M, Raushel FM. Biosynthesis of UDP-α- N-Acetyl-d -mannosaminuronic Acid and CMP-β- N-Acetyl-d-neuraminic Acid for the Capsular Polysaccharides of Campylobacter jejuni. Biochemistry 2024; 63:688-698. [PMID: 38382015 PMCID: PMC10919079 DOI: 10.1021/acs.biochem.3c00664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 01/10/2024] [Accepted: 02/02/2024] [Indexed: 02/23/2024]
Abstract
Campylobacter jejuni is a human pathogen and a leading cause of food poisoning in North America and Europe. The exterior surface of the bacterial cell wall is attached to a polymeric coat of sugar molecules known as the capsular polysaccharide (CPS) that helps protect the organism from the host immune response. The CPS is composed of a repeating sequence of common and unusual sugar residues. In the HS:11 serotype of C. jejuni, we identified two enzymes in the gene cluster for CPS formation that are utilized for the biosynthesis of UDP-α-N-acetyl-d-mannosaminuronic acid (UDP-ManNAcA). In the first step, UDP-α-N-acetyl-d-glucosamine (UDP-GlcNAc) is epimerized at C2 to form UDP-α-N-acetyl-d-mannosamine (UDP-ManNAc). This product is then oxidized by a NAD+-dependent C6-dehydrogenase to form UDP-ManNAcA. In the HS:6 serotype (C. jejuni strain 81116), we identified three enzymes that are required for the biosynthesis of CMP-β-N-acetyl-d-neuraminic acid (CMP-Neu5Ac). In the first step, UDP-GlcNAc is epimerized at C2 and subsequently hydrolyzed to form N-acetyl-d-mannosamine (ManNAc) with the release of UDP. This product is then condensed with PEP by N-acetyl-d-neuraminate synthase to form N-acetyl-d-neuraminic acid (Neu5Ac). In the final step, CMP-N-acetyl-d-neuraminic acid synthase utilizes CTP to convert this product into CMP-Neu5Ac. A bioinformatic analysis of these five enzymes from C. jejuni serotypes HS:11 and HS:6 identified other bacterial species that can produce UDP-ManNAcA or CMP-Neu5Ac for CPS formation.
Collapse
Affiliation(s)
| | - Frank M. Raushel
- Department of Chemistry, Texas A&M University, College
Station, Texas 77845, United States
| |
Collapse
|
2
|
Tian G, Qin C, Hu J, Zou X, Yin J. Effect of Side-Chain Functional Groups in the Immunogenicity of Bacterial Surface Glycans. Molecules 2023; 28:7112. [PMID: 37894591 PMCID: PMC10609480 DOI: 10.3390/molecules28207112] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 10/13/2023] [Accepted: 10/13/2023] [Indexed: 10/29/2023] Open
Abstract
Glycans on the surface of bacteria have diverse and essential biological functions and have widely been employed for treating various bacterial infectious diseases. Furthermore, these glycans comprise various functional groups, such as O-, N-, and carboxyl-modified, which significantly increase the diversity of glycan structures. These functional groups are not only crucial for glycans' structural identity but are also essential for their biological functions. Therefore, a clear understanding of the biological functions of these modified groups in corresponding bacterial glycans is crucial for their medical applications. Thus far, the activities of functional groups in some biomedical active carbohydrates have been elucidated. It has been shown that some functional groups are key constituents of biologically active bacterial glycans, while others are actually not essential and may even mask the functions of the glycans. This paper reviews the structures of naturally occurring side-chain functional groups in glycans located on the bacterial surface and their roles in immunological responses.
Collapse
Affiliation(s)
- Guangzong Tian
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China; (G.T.); (C.Q.); (X.Z.)
| | - Chunjun Qin
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China; (G.T.); (C.Q.); (X.Z.)
| | - Jing Hu
- Wuxi School of Medicine, Jiangnan University, Wuxi 214122, China;
| | - Xiaopeng Zou
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China; (G.T.); (C.Q.); (X.Z.)
| | - Jian Yin
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China; (G.T.); (C.Q.); (X.Z.)
- School of Life Sciences and Health Engineering, Jiangnan University, Wuxi 214122, China
| |
Collapse
|
3
|
Cifuente JO, Schulze J, Bethe A, Di Domenico V, Litschko C, Budde I, Eidenberger L, Thiesler H, Ramón Roth I, Berger M, Claus H, D'Angelo C, Marina A, Gerardy-Schahn R, Schubert M, Guerin ME, Fiebig T. A multi-enzyme machine polymerizes the Haemophilus influenzae type b capsule. Nat Chem Biol 2023; 19:865-877. [PMID: 37277468 PMCID: PMC10299916 DOI: 10.1038/s41589-023-01324-3] [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: 07/13/2022] [Accepted: 03/31/2023] [Indexed: 06/07/2023]
Abstract
Bacterial capsules have critical roles in host-pathogen interactions. They provide a protective envelope against host recognition, leading to immune evasion and bacterial survival. Here we define the capsule biosynthesis pathway of Haemophilus influenzae serotype b (Hib), a Gram-negative bacterium that causes severe infections in infants and children. Reconstitution of this pathway enabled the fermentation-free production of Hib vaccine antigens starting from widely available precursors and detailed characterization of the enzymatic machinery. The X-ray crystal structure of the capsule polymerase Bcs3 reveals a multi-enzyme machine adopting a basket-like shape that creates a protected environment for the synthesis of the complex Hib polymer. This architecture is commonly exploited for surface glycan synthesis by both Gram-negative and Gram-positive pathogens. Supported by biochemical studies and comprehensive 2D nuclear magnetic resonance, our data explain how the ribofuranosyltransferase CriT, the phosphatase CrpP, the ribitol-phosphate transferase CroT and a polymer-binding domain function as a unique multi-enzyme assembly.
Collapse
Affiliation(s)
- Javier O Cifuente
- Structural Glycobiology Laboratory, Biocruces Bizkaia Health Research Institute, Cruces University Hospital, Barakaldo, Spain
- Structural Glycobiology Laboratory, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
| | - Julia Schulze
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Andrea Bethe
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Valerio Di Domenico
- Structural Glycobiology Laboratory, Biocruces Bizkaia Health Research Institute, Cruces University Hospital, Barakaldo, Spain
| | - Christa Litschko
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Insa Budde
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Lukas Eidenberger
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Hauke Thiesler
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Isabel Ramón Roth
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Monika Berger
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Heike Claus
- Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
| | - Cecilia D'Angelo
- Structural Glycobiology Laboratory, Biocruces Bizkaia Health Research Institute, Cruces University Hospital, Barakaldo, Spain
- Structural Glycobiology Laboratory, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
| | - Alberto Marina
- Structural Glycobiology Laboratory, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
| | - Rita Gerardy-Schahn
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Mario Schubert
- Department of Biosciences and Medical Biology, University of Salzburg, Salzburg, Austria
| | - Marcelo E Guerin
- Structural Glycobiology Laboratory, Biocruces Bizkaia Health Research Institute, Cruces University Hospital, Barakaldo, Spain.
- Structural Glycobiology Laboratory, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain.
- Ikerbasque Basque Foundation for Science, Bilbao, Spain.
| | - Timm Fiebig
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany.
| |
Collapse
|
4
|
Sorieul C, Dolce M, Romano MR, Codée J, Adamo R. Glycoconjugate vaccines against antimicrobial resistant pathogens. Expert Rev Vaccines 2023; 22:1055-1078. [PMID: 37902243 DOI: 10.1080/14760584.2023.2274955] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 10/20/2023] [Indexed: 10/31/2023]
Abstract
INTRODUCTION Antimicrobial resistance (AMR) is responsible for the death of millions worldwide and stands as a major threat to our healthcare systems, which are heavily reliant on antibiotics to fight bacterial infections. The development of vaccines against the main pathogens involved is urgently required as prevention remains essential against the rise of AMR. AREAS COVERED A systematic research review was conducted on MEDLINE database focusing on the six AMR pathogens defined as ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Escherichia coli), which are considered critical or high priority pathogens by the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC). The analysis was intersecated with the terms carbohydrate, glycoconjugate, bioconjugate, glyconanoparticle, and multiple presenting antigen system vaccines. EXPERT OPINION Glycoconjugate vaccines have been successful in preventing meningitis and pneumoniae, and there are high expectations that they will play a key role in fighting AMR. We herein discuss the recent technological, preclinical, and clinical advances, as well as the challenges associated with the development of carbohydrate-based vaccines against leading AMR bacteria, with focus on the ESKAPE pathogens. The need of innovative clinical and regulatory approaches to tackle these targets is also highlighted.
Collapse
Affiliation(s)
- Charlotte Sorieul
- Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
| | - Marta Dolce
- GSK, Via Fiorentina 1, Siena, Italy
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Siena, Italy
| | | | - Jeroen Codée
- Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
| | | |
Collapse
|
5
|
Engle KA, Amos RA, Yang JY, Glushka J, Atmodjo M, Tan L, Huang C, Moremen KW, Mohnen D. Multiple Arabidopsis galacturonosyltransferases synthesize polymeric homogalacturonan by oligosaccharide acceptor-dependent or de novo synthesis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 109:1441-1456. [PMID: 34908202 PMCID: PMC8976717 DOI: 10.1111/tpj.15640] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 12/06/2021] [Accepted: 12/09/2021] [Indexed: 05/31/2023]
Abstract
Homogalacturonan (HG), the most abundant pectic glycan, functions as a cell wall structural and signaling molecule essential for plant growth, development and response to pathogens. HG exists as a component of pectic homoglycans, heteroglycans and glycoconjugates. HG is synthesized by members of the GALACTURONOSYLTRANSFERASE (GAUT) family. UDP-GalA-dependent homogalacturonan:galacturonosyltransferase (HG:GalAT) activity has previously been demonstrated for GAUTs 1, 4 and 11, as well as the GAUT1:GAUT7 complex. Here, we show that GAUTs 10, 13 and 14 are also HG:GalATs and that GAUTs 1, 10, 11, 13, 14 and 1:7 synthesize polymeric HG in vitro. Comparison of the in vitro HG:GalAT specific activities of the heterologously-expressed proteins demonstrates GAUTs 10 and 11 with the lowest, GAUT1 and GAUT13 with moderate, and GAUT14 and the GAUT1:GAUT7 complex with the highest HG:GalAT activity. GAUT13 and GAUT14 are also shown to de novo synthesize (initiate) HG synthesis in the absence of exogenous HG acceptors, an activity previously demonstrated for GAUT1:GAUT7. The rate of de novo HG synthesis by GAUT13 and GAUT14 is similar to their acceptor dependent HG synthesis, in contrast to GAUT1:GAUT7 for which de novo synthesis occurred at much lower rates than acceptor-dependent synthesis. The results suggest a unique role for de novo HG synthesis by GAUTs 13 and 14. The reducing end of GAUT13-de novo-synthesized HG has covalently attached UDP, indicating that UDP-GalA serves as both a donor and acceptor substrate during de novo HG synthesis. The functional significance of unique GAUT HG:GalAT catalytic properties in the synthesis of different pectin glycan or glycoconjugate structures is discussed.
Collapse
Affiliation(s)
- Kristen A. Engle
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602
- Department of Plant Biology, University of Georgia, Athens, Georgia 30602
| | - Robert A. Amos
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| | - Jeong-Yeh Yang
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602
| | - John Glushka
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602
| | - Melani Atmodjo
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| | - Li Tan
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602
| | - Chin Huang
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| | - Kelley W. Moremen
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| | - Debra Mohnen
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| |
Collapse
|
6
|
Di Guida R, Casillo A, Stellavato A, Kawai S, Ogawa T, Di Meo C, Kawamoto J, Kurihara T, Schiraldi C, Corsaro MM. Capsular polysaccharide from a fish-gut bacterium induces/promotes apoptosis of colon cancer cells in vitro through Caspases' pathway activation. Carbohydr Polym 2022; 278:118908. [PMID: 34973729 DOI: 10.1016/j.carbpol.2021.118908] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 11/04/2021] [Accepted: 11/13/2021] [Indexed: 11/02/2022]
Abstract
Among the widespread malignancies colorectal cancer is the most lethal. Treatments of this malignant tumor include surgery for lesions and metastases, radiotherapy, immunotherapy, and chemotherapy. Nevertheless, novel therapies to reduce morbidity and mortality are demanding. Natural products, such as polysaccharides, can be a valuable alternative to sometimes very toxic chemotherapeutical agents, also because they are biocompatible and biodegradable biomaterials. Microbial polysaccharides have been demonstrated to fulfill this requirement. In this paper, the results about the structure and the activity of a capsular polysaccharide isolated from the psychrotroph Pseudoalteromonas nigrifaciens Sq02-Rifr, newly isolated from the fish intestine, have been described. The characterization has been obtained by spectroscopic and chemical methods, and it is supported by the bioinformatic analysis. The polymer activates Caspases 3 and 9 on colon cancer cells CaCo-2 and HCT-116, indicating a promising antitumor effect, and suggesting a potential capacity of CPS to induce apoptosis.
Collapse
Affiliation(s)
- Rossella Di Guida
- Department of Chemical Sciences, University of Naples "Federico II", Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Naples, Italy.
| | - Angela Casillo
- Department of Chemical Sciences, University of Naples "Federico II", Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Naples, Italy.
| | - Antonietta Stellavato
- Department of Experimental Medicine, Section of Biotechnology Medical Histology and Molecular Biology, University of Campania "Luigi Vanvitelli", via L. De Crecchio n 7, 80138 Naples, Italy.
| | - Soichiro Kawai
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Takuya Ogawa
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Celeste Di Meo
- Department of Experimental Medicine, Section of Biotechnology Medical Histology and Molecular Biology, University of Campania "Luigi Vanvitelli", via L. De Crecchio n 7, 80138 Naples, Italy.
| | - Jun Kawamoto
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Tatsuo Kurihara
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
| | - Chiara Schiraldi
- Department of Experimental Medicine, Section of Biotechnology Medical Histology and Molecular Biology, University of Campania "Luigi Vanvitelli", via L. De Crecchio n 7, 80138 Naples, Italy.
| | - Maria Michela Corsaro
- Department of Chemical Sciences, University of Naples "Federico II", Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Naples, Italy.
| |
Collapse
|
7
|
Sheikhi Moghaddam L, Adegbite A, McCarthy PC. Investigation of bioluminescence-based assays for determination of kinetic parameters for the bifunctional Neisseria meningitidis serogroup W capsule polymerase. BMC Res Notes 2021; 14:417. [PMID: 34794506 PMCID: PMC8600345 DOI: 10.1186/s13104-021-05831-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 11/03/2021] [Indexed: 12/02/2022] Open
Abstract
Objective Neisseria meningitidis is a Gram-negative bacterium that causes meningitis. N. meningitidis serogroup W (NmW) capsule polymerase synthesizes capsular polysaccharide of this serogroup. This enzyme could be a tool for meningococcal glycoconjugate vaccine development. Our long-term goal is to control activity of the NmW capsule polymerase for production of defined carbohydrates for vaccines. The enzyme lacks a simple, high-throughput activity assay. Here, we describe the use of high-throughput bioluminescence assays (CMP-Glo and UDP-Glo by Promega) to investigate NmW capsule polymerase activity. These assays detect free nucleotides produced during transfer of sugar from UDP-Galactose and CMP-Sialic Acid to an acceptor. Kinetic studies using NmW hydrolyzed polysaccharide (PS) acceptor are described as well as preliminary work with a sialic acid trimer (DP3) acceptor. Results In CMP-Glo kinetic studies, with constant donor (80 µM) and varied NmW hydrolyzed polysaccharide (0–2000 µg/mL), a Km of 629.2 ± 101.4 µg/mL and a Vmax of 0.8965 ± 0.05823 µM/min was obtained. Using UDP-Glo, Km and Vmax values of 13.84 ± 9.675 µM and 0.6205 ± 0.1331 µM/min were obtained with varied CMP-NeuNAc (0–80 µM) and constant acceptor (400 µg/mL) and UDP-Gal (80 µM). This is the first report of using bioluminescence assays for NmW kinetics. Supplementary Information The online version contains supplementary material available at 10.1186/s13104-021-05831-1.
Collapse
Affiliation(s)
- Laleh Sheikhi Moghaddam
- Bioenvironmental Sciences Program, Morgan State University, 1700 East Cold Spring Lane, Baltimore, MD, 21251, USA.,Department of Chemistry, Morgan State University, 1700 East Cold Spring Lane, Baltimore, MD, 21251, USA
| | - Ayobami Adegbite
- Bioenvironmental Sciences Program, Morgan State University, 1700 East Cold Spring Lane, Baltimore, MD, 21251, USA.,Department of Chemistry, Morgan State University, 1700 East Cold Spring Lane, Baltimore, MD, 21251, USA
| | - Pumtiwitt C McCarthy
- Department of Chemistry, Morgan State University, 1700 East Cold Spring Lane, Baltimore, MD, 21251, USA.
| |
Collapse
|
8
|
Adegbite A, McCarthy PC. Recent and Future Advances in the Chemoenzymatic Synthesis of Homogeneous Glycans for Bacterial Glycoconjugate Vaccine Development. Vaccines (Basel) 2021; 9:1021. [PMID: 34579258 PMCID: PMC8473158 DOI: 10.3390/vaccines9091021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 09/09/2021] [Accepted: 09/10/2021] [Indexed: 12/02/2022] Open
Abstract
Vaccines are important in preventing disease outbreaks and controlling the spread of disease in a population. A variety of vaccines exist, including subunit, recombinant, and conjugate vaccines. Glycoconjugate vaccines have been an important tool to fight against diseases caused by a number of bacteria. Glycoconjugate vaccines are often heterogeneous. Vaccines of the future are becoming more rationally designed to have a defined oligosaccharide chain length and position of conjugation. Homogenous vaccines could play an important role in assessing the relationship between vaccine structure and immune response. This review focuses on recent advances in the chemoenzymatic production of defined bacterial oligosaccharides for vaccine development with a focus on Neisseria meningitidis and selected WHO-prioritized antibacterial resistant-pathogens. We also provide some perspective on future advances in the chemoenzymatic synthesis of well-defined oligosaccharides.
Collapse
Affiliation(s)
- Ayobami Adegbite
- Bioenvironmental Sciences Program, Morgan State University, Baltimore, MD 21251, USA;
- Department of Chemistry, Morgan State University, Baltimore, MD 21251, USA
| | | |
Collapse
|
9
|
Berti F, Romano MR, Micoli F, Adamo R. Carbohydrate based meningococcal vaccines: past and present overview. Glycoconj J 2021; 38:401-409. [PMID: 33905086 PMCID: PMC8076658 DOI: 10.1007/s10719-021-09990-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 02/25/2021] [Accepted: 02/28/2021] [Indexed: 12/28/2022]
Abstract
Neisseria meningitidis is a major cause of bacterial meningitidis worldwide. Children less than five years and adolescents are particularly affected. Nearly all invasive strains are surrounded by a polysaccharide capsule, based on which, 12 N. meningitidis serogroups are differentiated. Six of them, A, B, C, W, X, and Y, cause the vast majority of infections in humans. Mono- and multi-valent carbohydrate-based vaccines against meningococcal infections have been licensed or are currently in clinical development. In this mini-review, an overview of the past and present approaches for producing meningococcal glycoconjugate vaccines is provided.
Collapse
|
10
|
Litschko C, Budde I, Berger M, Fiebig T. Exploitation of Capsule Polymerases for Enzymatic Synthesis of Polysaccharide Antigens Used in Glycoconjugate Vaccines. Methods Mol Biol 2021; 2183:313-330. [PMID: 32959251 DOI: 10.1007/978-1-0716-0795-4_16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The exploitation of recombinant enzymes for the synthesis of complex carbohydrates is getting increasing attention. Unfortunately, the analysis of the resulting products often requires advanced methods like nuclear magnetic resonance spectroscopy and mass spectrometry. Here, we use the capsule polymerases Cps4B and Cps11D from Actinobacillus pleuropneumoniae serotypes 4 and 11, respectively, as examples for the in vitro synthesis of capsule polymers similar to those used in glycoconjugate vaccine formulations. We demonstrate how substrate turnover in an enzymatic reaction can be analyzed by HPLC-based anion exchange chromatography and provide the protocol for separation and detection of UV-active polymer. Moreover, we describe how UV-inactive polymer can be separated and visualized using polyacrylamide gel electrophoresis followed by combined alcian blue-silver staining.
Collapse
Affiliation(s)
- Christa Litschko
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Insa Budde
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Monika Berger
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Timm Fiebig
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany.
| |
Collapse
|
11
|
Hurlburt NK, Guan J, Ong H, Yu H, Chen X, Fisher AJ. Structural characterization of a nonhydrolyzing UDP-GlcNAc 2-epimerase from Neisseria meningitidis serogroup A. Acta Crystallogr F Struct Biol Commun 2020; 76:557-567. [PMID: 33135674 PMCID: PMC7605110 DOI: 10.1107/s2053230x20013680] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 10/13/2020] [Indexed: 11/10/2022] Open
Abstract
Bacterial nonhydrolyzing UDP-N-acetylglucosamine 2-epimerases catalyze the reversible interconversion of UDP-N-acetylglucosamine (UDP-GlcNAc) and UDP-N-acetylmannosamine (UDP-ManNAc). UDP-ManNAc is an important intermediate in the biosynthesis of certain cell-surface polysaccharides, including those in some pathogenic bacteria, such as Neisseria meningitidis and Streptococcus pneumoniae. Many of these epimerases are allosterically regulated by UDP-GlcNAc, which binds adjacent to the active site and is required to initiate UDP-ManNAc epimerization. Here, two crystal structures of UDP-N-acetylglucosamine 2-epimerase from Neisseria meningitidis serogroup A (NmSacA) are presented. One crystal structure is of the substrate-free enzyme, while the other structure contains UDP-GlcNAc substrate bound to the active site. Both structures form dimers as seen in similar epimerases, and substrate binding to the active site induces a large conformational change in which two Rossmann-like domains clamp down on the substrate. Unlike other epimerases, NmSacA does not require UDP-GlcNAc to instigate the epimerization of UDP-ManNAc, although UDP-GlcNAc was found to enhance the rate of epimerization. In spite of the conservation of residues involved in binding the allosteric UDP-GlcNAc observed in similar UDP-GlcNAc 2-epimerases, the structures presented here do not contain UDP-GlcNAc bound in the allosteric site. These structural results provide additional insight into the mechanism and regulation of this critical enzyme and improve the structural understanding of the ability of NmSacA to epimerize modified substrates.
Collapse
Affiliation(s)
| | - Jasper Guan
- Department of Chemistry, University of California, Davis, CA 95616, USA
| | - Hoonsan Ong
- Department of Chemistry, University of California, Davis, CA 95616, USA
| | - Hai Yu
- Department of Chemistry, University of California, Davis, CA 95616, USA
| | - Xi Chen
- Department of Chemistry, University of California, Davis, CA 95616, USA
| | - Andrew J. Fisher
- Department of Chemistry, University of California, Davis, CA 95616, USA
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616, USA
| |
Collapse
|
12
|
Fiebig T, Cramer JT, Bethe A, Baruch P, Curth U, Führing JI, Buettner FFR, Vogel U, Schubert M, Fedorov R, Mühlenhoff M. Structural and mechanistic basis of capsule O-acetylation in Neisseria meningitidis serogroup A. Nat Commun 2020; 11:4723. [PMID: 32948778 PMCID: PMC7501274 DOI: 10.1038/s41467-020-18464-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 08/20/2020] [Indexed: 02/08/2023] Open
Abstract
O-Acetylation of the capsular polysaccharide (CPS) of Neisseria meningitidis serogroup A (NmA) is critical for the induction of functional immune responses, making this modification mandatory for CPS-based anti-NmA vaccines. Using comprehensive NMR studies, we demonstrate that O-acetylation stabilizes the labile anomeric phosphodiester-linkages of the NmA-CPS and occurs in position C3 and C4 of the N-acetylmannosamine units due to enzymatic transfer and non-enzymatic ester migration, respectively. To shed light on the enzymatic transfer mechanism, we solved the crystal structure of the capsule O-acetyltransferase CsaC in its apo and acceptor-bound form and of the CsaC-H228A mutant as trapped acetyl-enzyme adduct in complex with CoA. Together with the results of a comprehensive mutagenesis study, the reported structures explain the strict regioselectivity of CsaC and provide insight into the catalytic mechanism, which relies on an unexpected Gln-extension of a classical Ser-His-Asp triad, embedded in an α/β-hydrolase fold.
Collapse
Affiliation(s)
- Timm Fiebig
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany.
| | | | - Andrea Bethe
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Petra Baruch
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Jana I Führing
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
- Fraunhofer International Consortium for Anti-Infective Research (iCAIR), Hannover, Germany
| | - Falk F R Buettner
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Ulrich Vogel
- Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
| | - Mario Schubert
- Department of Biosciences, University of Salzburg, Salzburg, Austria
| | - Roman Fedorov
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Martina Mühlenhoff
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany.
| |
Collapse
|
13
|
Characteristics of Neisseria Species Colonized in the Human’s Nasopharynx. Jundishapur J Microbiol 2020. [DOI: 10.5812/jjm.99915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Context: Neisseria meningitidis is the causative agent of a life-threatening infection with high mortality and morbidity worldwide. The most common types of this bacterium are serogroups A, B, C, W135, X, and Y. Although in some countries, such as Iran, the meningococcal meningitis has been well monitored and controlled by the use of divalent and quadrivalent vaccines, other fatal infections caused by these bacteria are still an important threat. For the above reason, this review focused on the differences of Neisseria characteristics, particularly in capsular composition, pathogenic and commensal stages to a better understanding of how to manage Neisseria infections. Evidence Acquisition: In this review, PubMed, EMBASE, ScienceDirect, Scopus, and Google Scholar were searched for English-language publications on pathogenic or commensal strains of Neisseria, meningococcal disease, Neisseria biology, genetic diversity, molecular typing, serogroups, diagnostic, and epidemiology around the world up to July 2019. All articles and academic reports in the defined area of this research were considered too. The data were extracted and descriptively discussed. Results: We included 85 studies in the survey. The data analysis revealed that the distribution of meningococcal serogroups was different regionally. For example, the serogroups C and W-135 accounted for Africa and Latin America regions, serogroup B in the European countries, and rarely in the Western Pacific, and serogroups A and C were dominant in Asian countries. Although data set for laboratory-based diagnosis of N. meningitidis are available for all countries, only 30% of the countries rely on reference laboratories for serogroup determination, and more than half of the countries lack the ability of surveillance system. Nevertheless, molecular detection procedure is also available for all countries. The use of the meningococcal vaccine is a variable country by country, but most countries have applied the meningococcal vaccine, either divalent or quadrivalent, for the protection of high-risk groups. Conclusions: Owing to the geographical distribution of N. meningitidis serogroups in circulating, each country has to monitor for changes in serogroups diversity and its control management. Furthermore, laboratories should scale up the epidemiology and disease burden. It should be mentioned that quadrivalent meningococcal vaccines reduce the meningococcal disease burden sharply.
Collapse
|
14
|
Budde I, Litschko C, Führing JI, Gerardy-Schahn R, Schubert M, Fiebig T. An enzyme-based protocol for cell-free synthesis of nature-identical capsular oligosaccharides from Actinobacillus pleuropneumoniae serotype 1. J Biol Chem 2020; 295:5771-5784. [PMID: 32152227 PMCID: PMC7186170 DOI: 10.1074/jbc.ra120.012961] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 03/09/2020] [Indexed: 11/06/2022] Open
Abstract
Actinobacillus pleuropneumoniae (App) is the etiological agent of acute porcine pneumonia and responsible for severe economic losses worldwide. The capsule polymer of App serotype 1 (App1) consists of [4)-GlcNAc-β(1,6)-Gal-α-1-(PO4-] repeating units that are O-acetylated at O-6 of the GlcNAc. It is a major virulence factor and was used in previous studies in the successful generation of an experimental glycoconjugate vaccine. However, the application of glycoconjugate vaccines in the animal health sector is limited, presumably because of the high costs associated with harvesting the polymer from pathogen culture. Consequently, here we exploited the capsule polymerase Cps1B of App1 as an in vitro synthesis tool and an alternative for capsule polymer provision. Cps1B consists of two catalytic domains, as well as a domain rich in tetratricopeptide repeats (TPRs). We compared the elongation mechanism of Cps1B with that of a ΔTPR truncation (Cps1B-ΔTPR). Interestingly, the product profiles displayed by Cps1B suggested processive elongation of the nascent polymer, whereas Cps1B-ΔTPR appeared to work in a more distributive manner. The dispersity of the synthesized products could be reduced by generating single-action transferases and immobilizing them on individual columns, separating the two catalytic activities. Furthermore, we identified the O-acetyltransferase Cps1D of App1 and used it to modify the polymers produced by Cps1B. Two-dimensional NMR analyses of the products revealed O-acetylation levels identical to those of polymer harvested from App1 culture supernatants. In conclusion, we have established a protocol for the pathogen-free in vitro synthesis of tailored, nature-identical App1 capsule polymers.
Collapse
Affiliation(s)
- Insa Budde
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover, Germany
| | - Christa Litschko
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover, Germany
| | - Jana I Führing
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover, Germany; Fraunhofer International Consortium for Anti-Infective Research (iCAIR), 30625 Hannover, Germany
| | - Rita Gerardy-Schahn
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover, Germany; Fraunhofer International Consortium for Anti-Infective Research (iCAIR), 30625 Hannover, Germany
| | - Mario Schubert
- Department of Biosciences, University of Salzburg, 5020 Salzburg, Austria
| | - Timm Fiebig
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover, Germany.
| |
Collapse
|
15
|
Zhang X, Sheng W, Li K, Rong Y, Wu Q, Meng Q, Kong Y, Chen M. Substrate specificity of the galactokinase from the human gut symbiont Akkermansia muciniphila ATCC BAA-835. Enzyme Microb Technol 2020; 139:109568. [PMID: 32732027 DOI: 10.1016/j.enzmictec.2020.109568] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 04/02/2020] [Accepted: 04/03/2020] [Indexed: 11/16/2022]
Abstract
Galactokinases, which catalyze the phosphorylation of galactose and possible other monosaccharides, can provide an activated sugar donor to synthesize sugar-containing molecules. In this study, a novel galactokinase from human gut symbiont Akkermansia muciniphila ATCC BAA-835 (GalKAmu) was expressed and characterized. GalKAmu displayed broad substrate tolerance, with catalytic activity towards Gal (100 %), GalN (100 %), GalA (20.2 %), Glc (52.5 %), GlcNAc (15.5 %), Xyl (<5%), ManNAc (58 %), ManF (37.4 %) and l-Glc (80 %). Most interestingly, this was the first GalK isoform which can tolerate ManNAc. Thus, our characterization of GalKAmu broadens the substrate selection of galactokinases.
Collapse
Affiliation(s)
- Xunlian Zhang
- The State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Qingdao, Shandong, 266237, China
| | - Weihao Sheng
- The State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Qingdao, Shandong, 266237, China
| | - Kun Li
- The State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Qingdao, Shandong, 266237, China
| | - Yongheng Rong
- The State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Qingdao, Shandong, 266237, China
| | - Qizheng Wu
- The State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Qingdao, Shandong, 266237, China
| | - Qingyun Meng
- The State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Qingdao, Shandong, 266237, China
| | - Yun Kong
- The State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Qingdao, Shandong, 266237, China.
| | - Min Chen
- The State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Qingdao, Shandong, 266237, China.
| |
Collapse
|
16
|
MacCalman TE, Phillips-Jones MK, Harding SE. Glycoconjugate vaccines: some observations on carrier and production methods. Biotechnol Genet Eng Rev 2020; 35:93-125. [PMID: 32048549 DOI: 10.1080/02648725.2019.1703614] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Glycoconjugate vaccines use protein carriers to improve the immune response to polysaccharide antigens. The protein component allows the vaccine to interact with T cells, providing a stronger and longer-lasting immune response than a polysaccharide interacting with B cells alone. Whilst in theory the mere presence of a protein component in a vaccine should be sufficient to improve vaccine efficacy, the extent of improvement varies. In the present review, a comparison of the performances of vaccines developed with and without a protein carrier are presented. The usefulness of analytical tools for macromolecular integrity assays, in particular nuclear magnetic resonance, circular dichroism, analytical ultracentrifugation and SEC coupled to multi-angle light scattering (MALS) is indicated. Although we focus mainly on bacterial capsular polysaccharide-protein vaccines, some consideration is also given to research on experimental cancer vaccines using zwitterionic polysaccharides which, unusually for polysaccharides, are able to invoke T-cell responses and have been used in the development of potential all-polysaccharide-based cancer vaccines.A general trend of improved immunogenicity for glycoconjugate vaccines is described. Since the immunogenicity of a vaccine will also depend on carrier protein type and the way in which it has been linked to polysaccharide, the effects of different carrier proteins and production methods are also reviewed. We suggest that, in general, there is no single best carrier for use in glycoconjugate vaccines. This indicates that the choice of carrier protein is optimally made on a case-by-case basis, based on what generates the best immune response and can be produced safely in each individual case.Abbreviations: AUC: analytical ultracentrifugation; BSA: bovine serum albumin; CD: circular dichroism spectroscopy; CPS: capsular polysaccharide; CRM197: Cross Reactive Material 197; DT: diphtheria toxoid; Hib: Haemophilius influenzae type b; MALS: multi-angle light scattering; Men: Neisseria menigitidis; MHC-II: major histocompatibility complex class II; NMR: nuclear magnetic resonance spectroscopy; OMP: outer membrane protein; PRP: polyribosyl ribitol phosphate; PSA: Polysaccharide A1; Sa: Salmonella; St.: Streptococcus; SEC: size exclusion chromatography; Sta: Staphylococcus; TT: tetanus toxoid; ZPS: zwitterionic polysaccharide(s).
Collapse
Affiliation(s)
- Thomas E MacCalman
- National Centre for Macromolecular Hydrodynamics, University of Nottingham, Nottingham, UK
| | - Mary K Phillips-Jones
- National Centre for Macromolecular Hydrodynamics, University of Nottingham, Nottingham, UK
| | - Stephen E Harding
- National Centre for Macromolecular Hydrodynamics, University of Nottingham, Nottingham, UK.,Kulturhistorisk Museum, University of Oslo, Oslo, Norway
| |
Collapse
|
17
|
Abstract
Extracellular polysaccharides and glycoproteins of pathogenic bacteria assist in adherence, autoaggregation, biofilm formation, and host immune system evasion. As a result, considerable research in the field of glycobiology is dedicated to study the composition and function of glycans associated with virulence, as well as the enzymes involved in their biosynthesis with the aim to identify novel antibiotic targets. Especially, insights into the enzyme mechanism, substrate binding, and transition-state structures are valuable as a starting point for rational inhibitor design. An intriguing aspect of enzymes that generate or process polysaccharides and glycoproteins is the level of processivity. The existence of enzymatic processivity reflects the need for regulation of the final glycan/glycoprotein length and structure, depending on the role they perform. In this Review, we describe the currently reported examples of various processive enzymes involved in polymerization and transfer of sugar moieties, predominantly in bacterial pathogens, with a focus on the biochemical methods, to showcase the importance of studying processivity for understanding the mechanism.
Collapse
Affiliation(s)
- Liubov Yakovlieva
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG Groningen, The Netherlands
| | - Marthe T. C. Walvoort
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG Groningen, The Netherlands
| |
Collapse
|
18
|
Micoli F, Del Bino L, Alfini R, Carboni F, Romano MR, Adamo R. Glycoconjugate vaccines: current approaches towards faster vaccine design. Expert Rev Vaccines 2019; 18:881-895. [PMID: 31475596 DOI: 10.1080/14760584.2019.1657012] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Introduction: Over the last decades, glycoconjugate vaccines have been proven to be a successful strategy to prevent infectious diseases. Many diseases remain to be controlled, especially in developing countries, and emerging antibiotic-resistant bacteria present an alarming public-health threat. The increasing complexity of future vaccines, and the need to accelerate development processes have triggered the development of faster approaches to glycoconjugate vaccines design. Areas covered: This review provides an overview of recent progress in glycoconjugation technologies toward faster vaccine design. Expert opinion: Among the different emerging approaches, glycoengineering has the potential to combine glycan assembly and conjugation to carrier systems (such as proteins or outer membrane vesicles) in one step, resulting in a simplified manufacturing process and fewer analytical controls. Chemical and enzymatic strategies, and their automation can facilitate glycoepitope identification for vaccine design. Other approaches, such as the liposomal encapsulation of polysaccharides, potentially enable fast and easy combination of numerous antigens in the same formulation. Additional progress is envisaged in the near future, and some of these systems still need to be further validated in humans. In parallel, new strategies are needed to accelerate the vaccine development process, including the associated clinical trials, up to vaccine release onto the market.
Collapse
Affiliation(s)
- Francesca Micoli
- Technology Platform, GSK Vaccines Institute for Global Health s.r.l , Siena , Italy
| | | | - Renzo Alfini
- Technology Platform, GSK Vaccines Institute for Global Health s.r.l , Siena , Italy
| | | | | | | |
Collapse
|
19
|
Amos RA, Pattathil S, Yang JY, Atmodjo MA, Urbanowicz BR, Moremen KW, Mohnen D. A two-phase model for the non-processive biosynthesis of homogalacturonan polysaccharides by the GAUT1:GAUT7 complex. J Biol Chem 2018; 293:19047-19063. [PMID: 30327429 DOI: 10.1074/jbc.ra118.004463] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 10/08/2018] [Indexed: 11/06/2022] Open
Abstract
Homogalacturonan (HG) is a pectic glycan in the plant cell wall that contributes to plant growth and development and cell wall structure and function, and interacts with other glycans and proteoglycans in the wall. HG is synthesized by the galacturonosyltransferase (GAUT) gene family. Two members of this family, GAUT1 and GAUT7, form a heteromeric enzyme complex in Arabidopsis thaliana Here, we established a heterologous GAUT expression system in HEK293 cells and show that co-expression of recombinant GAUT1 with GAUT7 results in the production of a soluble GAUT1:GAUT7 complex that catalyzes elongation of HG products in vitro The reaction rates, progress curves, and product distributions exhibited major differences dependent upon small changes in the degree of polymerization (DP) of the oligosaccharide acceptor. GAUT1:GAUT7 displayed >45-fold increased catalytic efficiency with DP11 acceptors relative to DP7 acceptors. Although GAUT1:GAUT7 synthesized high-molecular-weight polymeric HG (>100 kDa) in a substrate concentration-dependent manner typical of distributive (nonprocessive) glycosyltransferases with DP11 acceptors, reactions primed with short-chain acceptors resulted in a bimodal product distribution of glycan products that has previously been reported as evidence for a processive model of GT elongation. As an alternative to the processive glycosyltransfer model, a two-phase distributive elongation model is proposed in which a slow phase, which includes the de novo initiation of HG and elongation of short-chain acceptors, is distinguished from a phase of rapid elongation of intermediate- and long-chain acceptors. Upon reaching a critical chain length of DP11, GAUT1:GAUT7 elongates HG to high-molecular-weight products.
Collapse
Affiliation(s)
- Robert A Amos
- From the Complex Carbohydrate Research Center and.,the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| | | | | | - Melani A Atmodjo
- From the Complex Carbohydrate Research Center and.,the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| | | | - Kelley W Moremen
- From the Complex Carbohydrate Research Center and.,the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| | - Debra Mohnen
- From the Complex Carbohydrate Research Center and .,the Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602
| |
Collapse
|
20
|
Calloni I, Unione L, Jiménez-Osés G, Corzana F, Del Bino L, Corrado A, Pitirollo O, Colombo C, Lay L, Adamo R, Jiménez-Barbero J. The Conformation of the Mannopyranosyl Phosphate Repeating Unit of the Capsular Polysaccharide of Neisseria meningitidis Serogroup A and Its Carba-Mimetic. European J Org Chem 2018; 2018:4548-4555. [PMID: 30443159 PMCID: PMC6220853 DOI: 10.1002/ejoc.201801003] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Indexed: 11/07/2022]
Abstract
Neisseria meningitidis serogroup A (MenA) is an aerobic diplococcal Gram-negative bacterium responsible for epidemic meningitis disease. Its capsular polysaccharide (CPS) has been identified as the primary virulence factor of MenA. This polysaccharide suffers from chemical lability in water. Thus, the design and synthesis of novel and hydrolytically stable structural analogues of MenA CPS may provide additional tools for the development of therapies against this disease. In this context, the structural features of the natural phosphorylated monomer have been analyzed and compared to those of its carba-analogue, where the endocyclic oxygen has been replaced by a methylene moiety. The lowest energy geometries of the different molecules have been calculated using a combination of quantum mechanical techniques and molecular dynamics simulations. The predicted results have been compared and validated using NMR experiments. The results indicate that the more stable designed glycomimetics may adopt the conformation adopted by the natural monomer, although they display a wider flexibility around the torsional degrees of freedom.
Collapse
Affiliation(s)
- Ilaria Calloni
- Chemical Glycobiology Lab CIC bioGUNE Bizkaia Technology Park, Building 800 48160 Derio Spain.,Department of Organic Chemistry II Faculty of Science and Technology University of the Basque Country, EHU-UPV Leioa Spain
| | - Luca Unione
- Atlas Molecular Pharma Bizkaia Technology Park, Building 800 48160 Derio Spain
| | - Gonzalo Jiménez-Osés
- Departamento de Quimica Universidad de la Rioja Centro Científico Tecnológico Spain
| | - Francisco Corzana
- Departamento de Quimica Universidad de la Rioja Centro Científico Tecnológico Spain
| | | | - Alessio Corrado
- Glycobiology Lab GSK Via Fiorentina 10 Siena Italy.,Department of Chemistry and ISTM_CNR University of Milan Via Golgi 19 20133 Milan Italy
| | - Olimpia Pitirollo
- Department of Chemistry and ISTM_CNR University of Milan Via Golgi 19 20133 Milan Italy
| | - Cinzia Colombo
- Department of Chemistry and ISTM_CNR University of Milan Via Golgi 19 20133 Milan Italy
| | - Luigi Lay
- Department of Chemistry and ISTM_CNR University of Milan Via Golgi 19 20133 Milan Italy
| | | | - Jesús Jiménez-Barbero
- Chemical Glycobiology Lab CIC bioGUNE Bizkaia Technology Park, Building 800 48160 Derio Spain.,Department of Organic Chemistry II Faculty of Science and Technology University of the Basque Country, EHU-UPV Leioa Spain.,Basque Foundation for Science (IKERBASQUE) 48009 Bilbao Spain
| |
Collapse
|
21
|
Sharyan A, Gonzalez C, Ukaegbu O, Powell K, McCarthy PC. Determination of the binding affinities of Neisseria meningitidis serogroup W capsule polymerase with two nucleotide sugar substrates. BMC Res Notes 2018; 11:482. [PMID: 30012207 PMCID: PMC6048754 DOI: 10.1186/s13104-018-3596-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 07/12/2018] [Indexed: 01/22/2023] Open
Abstract
Objective Meningococcal meningitis is a public health burden. Immunization strategies have reduced global incidence of the disease. Glycoconjugate vaccines are the most effective type of vaccine to combat most causes of meningococcal meningitis. These vaccines contain capsular polysaccharide fragments from disease-causing serogroups of Neisseria meningitidis that are chemically attached to a carrier protein. The enzymes responsible for capsular polysaccharide synthesis can serve as tools to make these critical vaccine components. One such enzyme is the N. meningitidis serogroup W capsule polymerase. This enzyme is responsible for creating the galactose-sialic acid containing capsular polysaccharide of this serogroup. Our aim in this study was to determine the binding affinities of nucleotide sugar donors CMP-sialic acid and UDP-galactose using a coupled transferase assay to inform future work to modulate polysaccharide synthesis by this enzyme. Results We determined a Km of 66.8 µM for CMP-sialic acid and a Km for UDP-galactose of 3.9 µM. These values are lower than reported values for other retaining galactosyltransferases and inverting sialyltransferases respectively. There were difficulties obtaining reliable data for galactosyltransferase activity. An alternate strategy is needed to assess kinetic parameters of the separate transferase activities for this enzyme. Electronic supplementary material The online version of this article (10.1186/s13104-018-3596-y) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Abeer Sharyan
- Department of Chemistry, Morgan State University, 1700 East Cold Spring Lane, Baltimore, MD, 21251, USA
| | - Cendy Gonzalez
- Department of Biology, Morgan State University, 1700 East Cold Spring Lane, Baltimore, MD, 21251, USA
| | - Ophelia Ukaegbu
- Department of Chemistry, Morgan State University, 1700 East Cold Spring Lane, Baltimore, MD, 21251, USA
| | - Kayla Powell
- Department of Chemistry, Morgan State University, 1700 East Cold Spring Lane, Baltimore, MD, 21251, USA
| | - Pumtiwitt C McCarthy
- Department of Chemistry, Morgan State University, 1700 East Cold Spring Lane, Baltimore, MD, 21251, USA.
| |
Collapse
|
22
|
Role of O-Acetylation in the Immunogenicity of Bacterial Polysaccharide Vaccines. Molecules 2018; 23:molecules23061340. [PMID: 29865239 PMCID: PMC6100563 DOI: 10.3390/molecules23061340] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 05/21/2018] [Accepted: 05/30/2018] [Indexed: 12/26/2022] Open
Abstract
The incidence of infectious diseases caused by several bacterial pathogens such as Haemophilus influenzae type b, Streptococcus pneumoniae, and Neisseria meningitidis, has been dramatically reduced over the last 25 years through the use of glycoconjugate vaccines. The structures of the bacterial capsular polysaccharide (CPS) antigens, extracted and purified from microbial cultures and obtained with very high purity, show that many of them are decorated by O-acetyl groups. While these groups are often considered important for the structural identity of the polysaccharides, they play a major role in the functional immune response to some vaccines such as meningococcal serogroup A and Salmonella typhi Vi, but do not seem to be important for many others, such as meningococcal serogroups C, W, Y, and type III Group B Streptococcus. This review discusses the O-acetylation status of CPSs and its role in the immunological responses of these antigens.
Collapse
|
23
|
Litschko C, Oldrini D, Budde I, Berger M, Meens J, Gerardy-Schahn R, Berti F, Schubert M, Fiebig T. A New Family of Capsule Polymerases Generates Teichoic Acid-Like Capsule Polymers in Gram-Negative Pathogens. mBio 2018; 9:e00641-18. [PMID: 29844111 PMCID: PMC5974469 DOI: 10.1128/mbio.00641-18] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 05/02/2018] [Indexed: 02/07/2023] Open
Abstract
Group 2 capsule polymers represent crucial virulence factors of Gram-negative pathogenic bacteria. They are synthesized by enzymes called capsule polymerases. In this report, we describe a new family of polymerases that combine glycosyltransferase and hexose- and polyol-phosphate transferase activity to generate complex poly(oligosaccharide phosphate) and poly(glycosylpolyol phosphate) polymers, the latter of which display similarity to wall teichoic acid (WTA), a cell wall component of Gram-positive bacteria. Using modeling and multiple-sequence alignment, we showed homology between the predicted polymerase domains and WTA type I biosynthesis enzymes, creating a link between Gram-negative and Gram-positive cell wall biosynthesis processes. The polymerases of the new family are highly abundant and found in a variety of capsule-expressing pathogens such as Neisseria meningitidis, Actinobacillus pleuropneumoniae, Haemophilus influenzae, Bibersteinia trehalosi, and Escherichia coli with both human and animal hosts. Five representative candidates were purified, their activities were confirmed using nuclear magnetic resonance (NMR) spectroscopy, and their predicted folds were validated by site-directed mutagenesis.IMPORTANCE Bacterial capsules play an important role in the interaction between a pathogen and the immune system of its host. During the last decade, capsule polymerases have become attractive tools for the production of capsule polymers applied as antigens in glycoconjugate vaccine formulations. Conventional production of glycoconjugate vaccines requires the cultivation of the pathogen and thus the highest biosafety standards, leading to tremendous costs. With regard to animal husbandry, where vaccines could avoid the extensive use of antibiotics, conventional production is not sufficiently cost-effective. In contrast, enzymatic synthesis of capsule polymers is pathogen-free and fast, offers high stereo- and regioselectivity, and works with high efficacy. The new capsule polymerase family described here vastly increases the toolbox of enzymes available for biotechnology purposes. Representatives are abundantly found in human pathogens but also in animal pathogens, paving the way for the exploitation of polymerases for the development of a new generation of vaccines for animal husbandry.
Collapse
Affiliation(s)
- Christa Litschko
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | | | - Insa Budde
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Monika Berger
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Jochen Meens
- Institute for Microbiology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Rita Gerardy-Schahn
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | | | - Mario Schubert
- Department of Biosciences, University of Salzburg, Salzburg, Austria
| | - Timm Fiebig
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| |
Collapse
|
24
|
Ghimire S, McCarthy PC. Capture of Pb 2+ and Cu 2+ Metal Cations by Neisseria meningitidis-type Capsular Polysaccharides. Biomolecules 2018; 8:E23. [PMID: 29734757 PMCID: PMC6023028 DOI: 10.3390/biom8020023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 05/02/2018] [Accepted: 05/02/2018] [Indexed: 12/14/2022] Open
Abstract
Heavy metal pollution of water is a significant environmental and public health concern. Current biological strategies for heavy metal removal from water are performed using microbial biopolymers, including polysaccharides, that are already fully formed. This creates limitations in adapting polysaccharides to increase binding affinity for specific metals. We propose that altering the specificity of polysaccharide-producing enzymes could be beneficial to improving metal capture by modified polysaccharides. We assess binding of Cu2+ and Pb2+ metal cations to Neisseria meningitidis-type polysaccharides. All concentrations of metal cations tested were able to completely bind to colominic acid. This polymer is equivalent to the capsular polysaccharide of N. meningitidis serogroup B comprised of a homopolymer of negatively charged sialic acid. There was slightly less binding observed with N. meningitidis serogroup W, which contains repeating units of the neutral sugar galactose and sialic acid. Our work represents the first assessment of the metal-binding properties of these capsular polysaccharides. Future work will seek to optimize metal-binding with Neisseria meningitidis serogroup W polysaccharide.
Collapse
Affiliation(s)
- Sujan Ghimire
- Department of Chemistry, Morgan State University, Baltimore, MD 21251, USA.
| | | |
Collapse
|
25
|
Oldrini D, Fiebig T, Romano MR, Proietti D, Berger M, Tontini M, De Ricco R, Santini L, Morelli L, Lay L, Gerardy-Schahn R, Berti F, Adamo R. Combined Chemical Synthesis and Tailored Enzymatic Elongation Provide Fully Synthetic and Conjugation-Ready Neisseria meningitidis Serogroup X Vaccine Antigens. ACS Chem Biol 2018; 13:984-994. [PMID: 29481045 DOI: 10.1021/acschembio.7b01057] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Studies on the polymerization mode of Neisseria meningitidis serogroup X capsular polymerase CsxA recently identified a truncated construct that can be immobilized and used for length controlled on-column production of oligosaccharides. Here, we combined the use of a synthetic acceptor bearing an appendix for carrier protein conjugation and the on-column process to a novel chemo-enzymatic strategy. After protein coupling of the size optimized oligosaccharide produced by the one-pot elongation procedure, we obtained a more homogeneous glycoconjugate compared to the one previously described starting from the natural polysaccharide. Mice immunized with the conjugated fully synthetic oligomer elicited functional antibodies comparable to controls immunized with the current benchmark MenX glycoconjugates prepared from the natural capsule polymer or from fragments of it enzymatically elongated. This pathogen-free technology allows the fast total in vitro construction of predefined bacterial polysaccharide fragments. Compared to conventional synthetic protocols, the procedure is more expeditious and drastically reduces the number of purification steps to achieve the oligomers. Furthermore, the presence of a linker for conjugation in the synthetic acceptor minimizes manipulations on the enzymatically produced glycan prior to protein conjugation. This approach enriches the methods for fast construction of complex bacterial carbohydrates.
Collapse
Affiliation(s)
| | - Timm Fiebig
- Institute of Clinical Biochemistry, Hannover Medical School, 30625 Hannover, Germany
| | | | | | - Monika Berger
- Institute of Clinical Biochemistry, Hannover Medical School, 30625 Hannover, Germany
| | | | | | | | - Laura Morelli
- University of Milan, Department of Chemistry, via Golgi 19, 20133, Milan, Italy
| | - Luigi Lay
- University of Milan, Department of Chemistry, via Golgi 19, 20133, Milan, Italy
| | - Rita Gerardy-Schahn
- Institute of Clinical Biochemistry, Hannover Medical School, 30625 Hannover, Germany
| | | | | |
Collapse
|
26
|
Meningococcal Vaccines: Current Status and Emerging Strategies. Vaccines (Basel) 2018; 6:vaccines6010012. [PMID: 29495347 PMCID: PMC5874653 DOI: 10.3390/vaccines6010012] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 02/21/2018] [Accepted: 02/23/2018] [Indexed: 12/13/2022] Open
Abstract
Neisseria meningitidis causes most cases of bacterial meningitis. Meningococcal meningitis is a public health burden to both developed and developing countries throughout the world. There are a number of vaccines (polysaccharide-based, glycoconjugate, protein-based and combined conjugate vaccines) that are approved to target five of the six disease-causing serogroups of the pathogen. Immunization strategies have been effective at helping to decrease the global incidence of meningococcal meningitis. Researchers continue to enhance these efforts through discovery of new antigen targets that may lead to a broadly protective vaccine and development of new methods of homogenous vaccine production. This review describes current meningococcal vaccines and discusses some recent research discoveries that may transform vaccine development against N. meningitidis in the future.
Collapse
|
27
|
Weyant KB, Mills DC, DeLisa MP. Engineering a new generation of carbohydrate-based vaccines. Curr Opin Chem Eng 2018; 19:77-85. [PMID: 30568873 DOI: 10.1016/j.coche.2017.12.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Recent advances in chemical synthesis, conjugation chemistry, engineered biosynthesis, and formulation design have spawned a new generation of vaccines that incorporate carbohydrate antigens. By providing better immunity against a variety of pathogens or malignant cells and lowering the cost of production, these developments overcome many of the limitations associated with conventional vaccines involving polysaccharides. Moreover, the resulting vaccine candidates are shedding light on how the immune system responds to carbohydrates and providing mechanistic insight that can help guide future vaccine design. Here, we review recent engineering efforts to develop and manufacture carbohydrate-based vaccines that are efficacious, durable, and cost-effective.
Collapse
Affiliation(s)
- Kevin B Weyant
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853 USA
| | - Dominic C Mills
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853 USA
| | - Matthew P DeLisa
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853 USA.,Comparative Biomedical Sciences, Cornell University, Ithaca, NY 14853 USA.,Department of Biomedical Engineering, Cornell University, Ithaca, NY 14853 USA
| |
Collapse
|
28
|
Fiebig T, Litschko C, Freiberger F, Bethe A, Berger M, Gerardy-Schahn R. Efficient solid-phase synthesis of meningococcal capsular oligosaccharides enables simple and fast chemoenzymatic vaccine production. J Biol Chem 2017; 293:953-962. [PMID: 29187601 DOI: 10.1074/jbc.ra117.000488] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 11/28/2017] [Indexed: 12/22/2022] Open
Abstract
Neisseria meningitidis serogroups A and X are among the leading causes of bacterial meningitis in the African meningitis belt. Glycoconjugate vaccines, consisting of an antigenic carrier protein coupled to the capsular polysaccharide of the bacterial pathogen, are the most effective strategy for prevention of meningococcal disease. However, the distribution of effective glycoconjugate vaccines in this region is limited by the high cost of cultivating pathogens and purification of their capsular polysaccharides. Moreover, chemical approaches to synthesize oligosaccharide antigens have proven challenging. In the current study, we present a chemoenzymatic approach for generating tailored oligosaccharide fractions ready for activation and coupling to the carrier protein. In a first step, the elongation modes of recombinant capsular polymerases from Neisseria meningitidis serogroups A (CsaB) and X (CsxA) were characterized. We observed that CsaB is a distributive enzyme, and CsxA is a processive enzyme. Sequence comparison of these two stealth family proteins revealed a C-terminal extension in CsxA, which conferred processivity because of the existence of a second product-binding site. Deletion of the C-terminal domain converted CsxA into a distributive enzyme, allowing facile control of product length by adjusting the ratio of donor to acceptor sugars. Solid-phase fixation of the engineered capsular polymerases enabled rapid production of capsular polysaccharides with high yield and purity. In summary, the tools developed here provide critical steps toward reducing the cost of conjugate vaccine production, which will increase access in regions with the greatest need. Our work also facilitates efforts to study the relationship between oligosaccharide size and antigenicity.
Collapse
Affiliation(s)
- Timm Fiebig
- From the Institute of Clinical Biochemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Christa Litschko
- From the Institute of Clinical Biochemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Friedrich Freiberger
- From the Institute of Clinical Biochemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Andrea Bethe
- From the Institute of Clinical Biochemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Monika Berger
- From the Institute of Clinical Biochemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Rita Gerardy-Schahn
- From the Institute of Clinical Biochemistry, Hannover Medical School, 30625 Hannover, Germany
| |
Collapse
|
29
|
Abstract
Since 2004, when the first synthetic glycoconjugate vaccine against the pneumonia and meningitis causing bacterium Haemophilus influenza type b (Hib) approved for human use in Cuba was reported, 34 million doses of the synthetic vaccine have been already distributed in several countries under the commercial name of Quimi-Hib. However, despite the success of this product, no other synthetic glycoconjugate vaccine has been licensed in the following 13 years. As well as avoiding the need to handle pathogens, synthetic glycoconjugates offer clear advantages in terms of product characterization and the possibility to understand the parameters influencing immunogenicity. Nevertheless, large scale application of synthetic sugars has been perceived as challenging because of manufacturing costs and process complexity compared to natural polysaccharides. Chemoenzymatic approaches, one-pot protocols, and automated solid-phase synthesis are rendering carbohydrate production considerably more attractive for industrialization. Here we identify three areas where chemical approaches can advance this progress: (i) chemical or enzymatic methods enabling the delivery of the minimal polysaccharide portion responsible for an effective immune response; (ii) site-selective chemical or enzymatic conjugation strategies for the exploration of the conjugation point in immune responses against carbohydrate-based vaccines, and the consistent preparation of more homogeneous products; (iii) multicomponent constructs targeting receptors responsible for immune response modulation in order to control its quality and magnitude. We discuss how synthesis of bacterial oligosaccharides is useful toward understanding the polysaccharide portion responsible for immunogenicity, and for developing robust and consistent alternatives to natural heterogeneous polysaccharides. The synthesis of sugar analogues can lead to the identification of hydrolytically more stable versions of oligosaccharide antigens. The study of bacterial polysaccharide biosynthesis aids the development of in vitro hazard-free oligosaccharide production. Novel site-selective conjugation methods contribute toward deciphering the role of conjugation sites in the immunogenicity of glycoconjugates and prove to be particularly useful when glycans are conjugated to protein serving as carrier and antigen. The orthogonal incorporation of two different carbohydrate haptens enables the reduction of vaccine components. Finally, coordinated conjugation of glycans and small molecule immunopotentiators supports simplification of vaccine formulation and localization of adjuvant. Synergistic advancement of these areas, combined with competitive manufacturing processes, will contribute to a better understanding of the features guiding the immunological activity of glycoconjugates and, ultimately, to the design of improved, safer vaccines.
Collapse
|
30
|
Harale KR, Rout JK, Chhikara MK, Gill DS, Misra AK. Synthesis and immunochemical evaluation of a novel Neisseria meningitidis serogroup A tetrasaccharide and its conjugate. Org Chem Front 2017. [DOI: 10.1039/c7qo00468k] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A tetrameric repeating unit of capsular polysaccharide of Neisseria meningitidis serogroup A was synthesized which mimicked natural polysaccharide in immunochemical analysis.
Collapse
Affiliation(s)
- Kishore R. Harale
- MSD Wellcome Trust Hilleman Laboratories Pvt. Ltd
- New Delhi 110062
- India
| | - Jeetendra K. Rout
- MSD Wellcome Trust Hilleman Laboratories Pvt. Ltd
- New Delhi 110062
- India
| | | | - Davinder S. Gill
- MSD Wellcome Trust Hilleman Laboratories Pvt. Ltd
- New Delhi 110062
- India
| | | |
Collapse
|
31
|
An efficient cell free enzyme-based total synthesis of a meningococcal vaccine candidate. NPJ Vaccines 2016; 1:16017. [PMID: 29263856 PMCID: PMC5707881 DOI: 10.1038/npjvaccines.2016.17] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 07/14/2016] [Accepted: 08/03/2016] [Indexed: 11/14/2022] Open
Abstract
Invasive meningococcal disease (IMD) is a global health problem and vaccination has proven the most effective way of disease control. Neisseria meningitidis serogroup X (NmX) is an emerging threat in the African sub-Saharan meningitis belt, but no vaccine is available today. Leading vaccines against Nm are glycoconjugates, in which capsular polysaccharides isolated from large-scale pathogen cultures are conjugated to adjuvant proteins. Though safe and efficacious even in infants, high costs and biohazard associated with the production limit abundant application of glycoconjugate vaccines particularly in the most afflicted nations. An existing NmX vaccine candidate (CPSXn-CRM197) produced by established protocols from NmX capsule polysaccharide (CPSX) has been shown to elicit high bactericidal immunoglobulin G titres in mice. Here we describe the scalable in vitro synthesis of CPSXiv from chemically pure precursors by the use of recombinant NmX capsule polymerase. Application of the described coupling chemistry gives CPSXiv-CRM197, which in mouse vaccination experiments behaves identical to the benchmark CPSXn-CRM197. Excluding any biohazards, this novel process represents a paradigm shift in vaccine production and a premise towards vaccine manufacturing in emerging economies.
Collapse
|
32
|
Abstract
Neisseria meningitidis, a devastating pathogen exclusive to humans, expresses capsular polysaccharides that are the major meningococcal virulence determinants and the basis for successful meningococcal vaccines. With rare exceptions, the expression of capsule (serogroups A, B, C, W, X, Y) is required for systemic invasive meningococcal disease. Changes in capsule expression or structure (e.g. hypo- or hyper-encapsulation, capsule "switching", acetylation) can influence immunologic diagnostic assays or lead to immune escape. The loss or down-regulation of capsule is also critical in meningococcal biology facilitating meningococcal attachment, microcolony formation and the carriage state at human mucosal surfaces. Encapsulated meningococci contain a cps locus with promoters located in an intergenic region between the biosynthesis and the conserved capsule transport operons. The cps intergenic region is transcriptionally regulated (and thus the amount of capsule expressed) by IS element insertion, by a two-component system, MisR/MisS and through sequence changes that result in post-transcriptional RNA thermoregulation. Reversible on-off phase variation of capsule expression is controlled by slipped strand mispairing of homo-polymeric tracts and by precise insertion and excision of IS elements (e.g. IS1301) in the biosynthesis operon. Capsule structure can be altered by phase-variable expression of capsular polymer modification enzymes or "switched" through transformation and homologous recombination of different polymerases. Understanding the complex regulation of meningococcal capsule has important implications for meningococcal biology, pathogenesis, diagnostics, current and future vaccine development and vaccine strategies.
Collapse
Affiliation(s)
- Yih-Ling Tzeng
- a Department of Medicine , Emory University School of Medicine, Woodruff Health Sciences Center , Atlanta , GA , USA
| | - Jennifer Thomas
- a Department of Medicine , Emory University School of Medicine, Woodruff Health Sciences Center , Atlanta , GA , USA
| | - David S Stephens
- a Department of Medicine , Emory University School of Medicine, Woodruff Health Sciences Center , Atlanta , GA , USA
| |
Collapse
|
33
|
Litschko C, Romano MR, Pinto V, Claus H, Vogel U, Berti F, Gerardy-Schahn R, Fiebig T. The capsule polymerase CslB of Neisseria meningitidis serogroup L catalyzes the synthesis of a complex trimeric repeating unit comprising glycosidic and phosphodiester linkages. J Biol Chem 2015; 290:24355-66. [PMID: 26286750 DOI: 10.1074/jbc.m115.678094] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Indexed: 11/06/2022] Open
Abstract
Neisseria meningitidis is a human pathogen causing bacterial meningitis and sepsis. The capsular polysaccharide surrounding N. meningitidis is a major virulence factor. The capsular polysaccharide consists of polyhexosamine phosphates in N. meningitidis serogroups A and X. The capsule polymerases (CPs) of these serogroups are members of the Stealth protein family comprising d-hexose-1-phosphate transferases from bacterial and protozoan pathogens. CslA, one of two putative CPs of the pathophysiologically less relevant N. meningitidis serogroup L, is one of the smallest known Stealth proteins and caught our attention for structure-function analyses. Because the N. meningitidis serogroup L capsule polymer consists of a trimeric repeating unit ([→3)-β-d-GlcNAc-(1→3)-β-d-GlcNAc-(1→3)-α-d-GlcNAc-(1→OPO3→]n), we speculated that the two predicted CPs (CslA and CslB) work together in polymer production. Consequently, both enzymes were cloned, overexpressed, and purified as recombinant proteins. Contrary to our expectation, enzymatic testing identified CslB to be sufficient to catalyze the synthesis of the complex trimeric N. meningitidis serogroup L capsule polymer repeating unit. No polymerase activity was detected for CslA, although the enzyme facilitated the hydrolysis of UDP-GlcNAc. Bioinformatics analyses identified two glycosyltransferase (GT) domains in CslB. The N-terminal domain modeled with 100% confidence onto a number of GT-A folded proteins, whereas the C-terminal domain modeled with 100% confidence onto TagF, a GT-B folded teichoic acid polymerase from Staphylococcus epidermidis. Amino acid positions known to have critical catalytic functions in the template proteins were conserved in CslB, and their point mutation abolished enzyme activity. CslB represents an enzyme of so far unique complexity regarding both the catalyzed reaction and enzyme architecture.
Collapse
Affiliation(s)
- Christa Litschko
- From the Institute for Cellular Chemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover, Germany
| | | | - Vittoria Pinto
- Research, GSK Vaccines, Via Fiorentina 1, 53100 Siena, Italy, and
| | - Heike Claus
- the Institute for Hygiene and Microbiology, University of Würzburg, 97080 Würzburg, Germany
| | - Ulrich Vogel
- the Institute for Hygiene and Microbiology, University of Würzburg, 97080 Würzburg, Germany
| | - Francesco Berti
- Research, GSK Vaccines, Via Fiorentina 1, 53100 Siena, Italy, and
| | - Rita Gerardy-Schahn
- From the Institute for Cellular Chemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover, Germany
| | - Timm Fiebig
- From the Institute for Cellular Chemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover, Germany,
| |
Collapse
|
34
|
Shahbaaz M, Bisetty K, Ahmad F, Hassan MI. Towards New Drug Targets? Function Prediction of Putative Proteins of Neisseria meningitidis MC58 and Their Virulence Characterization. OMICS-A JOURNAL OF INTEGRATIVE BIOLOGY 2015; 19:416-34. [PMID: 26076386 DOI: 10.1089/omi.2015.0032] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Neisseria meningitidis is a Gram-negative aerobic diplococcus, responsible for a variety of meningococcal diseases. The genome of N. meningitidis MC58 is comprised of 2114 genes that are translated into 1953 proteins. The 698 genes (∼35%) encode hypothetical proteins (HPs), because no experimental evidence of their biological functions are available. Analyses of these proteins are important to understand their functions in the metabolic networks and may lead to the discovery of novel drug targets against the infections caused by N. meningitidis. This study aimed at the identification and categorization of each HP present in the genome of N. meningitidis MC58 using computational tools. Functions of 363 proteins were predicted with high accuracy among the annotated set of HPs investigated. The reliably predicted 363 HPs were further grouped into 41 different classes of proteins, based on their possible roles in cellular processes such as metabolism, transport, and replication. Our studies revealed that 22 HPs may be involved in the pathogenesis caused by this microorganism. The top two HPs with highest virulence scores were subjected to molecular dynamics (MD) simulations to better understand their conformational behavior in a water environment. We also compared the MD simulation results with other virulent proteins present in N. meningitidis. This study broadens our understanding of the mechanistic pathways of pathogenesis, drug resistance, tolerance, and adaptability for host immune responses to N. meningitidis.
Collapse
Affiliation(s)
- Mohd Shahbaaz
- 1 Department of Chemistry, Durban University of Technology , Durban, South Africa
| | - Krishna Bisetty
- 1 Department of Chemistry, Durban University of Technology , Durban, South Africa
| | - Faizan Ahmad
- 2 Center for Interdisciplinary Research in Basic Sciences , Jamia Millia Islamia, Jamia Nagar, New Delhi, 110025, India
| | - Md Imtaiyaz Hassan
- 2 Center for Interdisciplinary Research in Basic Sciences , Jamia Millia Islamia, Jamia Nagar, New Delhi, 110025, India
| |
Collapse
|
35
|
Qian Y, van Meel E, Flanagan-Steet H, Yox A, Steet R, Kornfeld S. Analysis of mucolipidosis II/III GNPTAB missense mutations identifies domains of UDP-GlcNAc:lysosomal enzyme GlcNAc-1-phosphotransferase involved in catalytic function and lysosomal enzyme recognition. J Biol Chem 2014; 290:3045-56. [PMID: 25505245 DOI: 10.1074/jbc.m114.612507] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
UDP-GlcNAc:lysosomal enzyme GlcNAc-1-phosphotransferase tags newly synthesized lysosomal enzymes with mannose 6-phosphate recognition markers, which are required for their targeting to the endolysosomal system. GNPTAB encodes the α and β subunits of GlcNAc-1-phosphotransferase, and mutations in this gene cause the lysosomal storage disorders mucolipidosis II and III αβ. Prior investigation of missense mutations in GNPTAB uncovered amino acids in the N-terminal region and within the DMAP domain involved in Golgi retention of GlcNAc-1-phosphotransferase and its ability to specifically recognize lysosomal hydrolases, respectively. Here, we undertook a comprehensive analysis of the remaining missense mutations in GNPTAB reported in mucolipidosis II and III αβ patients using cell- and zebrafish-based approaches. We show that the Stealth domain harbors the catalytic site, as some mutations in these regions greatly impaired the activity of the enzyme without affecting its Golgi localization and proteolytic processing. We also demonstrate a role for the Notch repeat 1 in lysosomal hydrolase recognition, as missense mutations in conserved cysteine residues in this domain do not affect the catalytic activity but impair mannose phosphorylation of certain lysosomal hydrolases. Rescue experiments using mRNA bearing Notch repeat 1 mutations in GNPTAB-deficient zebrafish revealed selective effects on hydrolase recognition that differ from the DMAP mutation. Finally, the mutant R587P, located in the spacer between Notch 2 and DMAP, was partially rescued by overexpression of the γ subunit, suggesting a role for this region in γ subunit binding. These studies provide new insight into the functions of the different domains of the α and β subunits.
Collapse
Affiliation(s)
- Yi Qian
- From the Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110 and
| | - Eline van Meel
- From the Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110 and
| | | | - Alex Yox
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602
| | - Richard Steet
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602
| | - Stuart Kornfeld
- From the Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110 and
| |
Collapse
|