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Cellular and Molecular Engineering of Glycan Sialylation in Heterologous Systems. Molecules 2021; 26:molecules26195950. [PMID: 34641494 PMCID: PMC8512710 DOI: 10.3390/molecules26195950] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 09/26/2021] [Accepted: 09/27/2021] [Indexed: 02/05/2023] Open
Abstract
Glycans have been shown to play a key role in many biological processes, such as signal transduction, immunogenicity, and disease progression. Among the various glycosylation modifications found on cell surfaces and in biomolecules, sialylation is especially important, because sialic acids are typically found at the terminus of glycans and have unique negatively charged moieties associated with cellular and molecular interactions. Sialic acids are also crucial for glycosylated biopharmaceutics, where they promote stability and activity. In this regard, heterogenous sialylation may produce variability in efficacy and limit therapeutic applications. Homogenous sialylation may be achieved through cellular and molecular engineering, both of which have gained traction in recent years. In this paper, we describe the engineering of intracellular glycosylation pathways through targeted disruption and the introduction of carbohydrate active enzyme genes. The focus of this review is on sialic acid-related genes and efforts to achieve homogenous, humanlike sialylation in model hosts. We also discuss the molecular engineering of sialyltransferases and their application in chemoenzymatic sialylation and sialic acid visualization on cell surfaces. The integration of these complementary engineering strategies will be useful for glycoscience to explore the biological significance of sialic acids on cell surfaces as well as the future development of advanced biopharmaceuticals.
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2
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Bacterial sialyltransferases and their use in biocatalytic cascades for sialo-oligosaccharide production. Biotechnol Adv 2020; 44:107613. [DOI: 10.1016/j.biotechadv.2020.107613] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 08/13/2020] [Accepted: 08/13/2020] [Indexed: 12/17/2022]
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3
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Mertsch A, He N, Yi D, Kickstein M, Fessner W. An α2,3-Sialyltransferase from Photobacterium phosphoreum with Broad Substrate Scope: Controlling Hydrolytic Activity by Directed Evolution. Chemistry 2020; 26:11614-11624. [PMID: 32596832 PMCID: PMC7540698 DOI: 10.1002/chem.202002277] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Indexed: 12/12/2022]
Abstract
Defined sialoglycoconjugates are important molecular probes for studying the role of sialylated glycans in biological systems. We show that the α2,3-sialyltransferase from Photobacterium phosphoreum JT-ISH-467 (2,3SiaTpph ) tolerates a very broad substrate scope for modifications in the sialic acid part, including bulky amide variation, C5/C9 substitution, and C5 stereoinversion. To reduce the enzyme's hydrolytic activity, which erodes the product yield, an extensive structure-guided mutagenesis study identified three variants that show up to five times higher catalytic efficiency for sialyltransfer, up to ten times lower efficiency for substrate hydrolysis, and drastically reduced product hydrolysis. Variant 2,3SiaTpph (A151D) displayed the best performance overall in the synthesis of the GM3 trisaccharide (α2,3-Neu5Ac-Lac) from lactose in a one-pot, two-enzyme cascade. Our study demonstrates that several complementary solutions can be found to suppress the common problem of undesired hydrolysis activity of microbial GT80 sialyltransferases. The new enzymes are powerful catalysts for the synthesis of a wide variety of complex natural and new-to-nature sialoconjugates for biological studies.
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Affiliation(s)
- Alexander Mertsch
- Institute of Organic Chemistry and BiochemistryTechnische Universität DarmstadtAlarich-Weiss-Strasse 464287DarmstadtGermany
| | - Ning He
- Institute of Organic Chemistry and BiochemistryTechnische Universität DarmstadtAlarich-Weiss-Strasse 464287DarmstadtGermany
| | - Dong Yi
- Institute of Organic Chemistry and BiochemistryTechnische Universität DarmstadtAlarich-Weiss-Strasse 464287DarmstadtGermany
| | - Michael Kickstein
- Institute of Organic Chemistry and BiochemistryTechnische Universität DarmstadtAlarich-Weiss-Strasse 464287DarmstadtGermany
| | - Wolf‐Dieter Fessner
- Institute of Organic Chemistry and BiochemistryTechnische Universität DarmstadtAlarich-Weiss-Strasse 464287DarmstadtGermany
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Dobie C, Montgomery AP, Szabo R, Skropeta D, Yu H. Computer-aided design of human sialyltransferase inhibitors of hST8Sia III. J Mol Recognit 2017; 31. [PMID: 29119617 DOI: 10.1002/jmr.2684] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Revised: 10/05/2017] [Accepted: 10/06/2017] [Indexed: 11/07/2022]
Abstract
Sialyltransferase (ST) upregulation and the resultant hypersialylation of tumour cell surfaces is an established hallmark of many cancers including lung, breast, ovarian, pancreatic and prostate cancer. The role of ST enzymes in tumour cell growth and metastasis, as well as links to multi-drug resistance, has seen ST inhibition emerge as a target for potential antimetastatic cancer treatments. The most potent of these reported inhibitors are transition-state analogues. Although there are several examples of these in the literature, many have suspected poor pharmacokinetic properties and are not readily synthetically accessible. A proposed solution to these problems is the use of a neutral carbamate or 1,2,3-triazole linker instead of the more commonly used phosphodiester linker, and replacing the traditionally utilised cytidine nucleotide with uridine. Another issue in this area is the paucity of structural information of human ST enzymes. However, in late 2015 the structure of human ST8Sia III was reported (only the second human ST described so far), creating the opportunity for structure-based design of selective ST8 inhibitors for the first time. Herein, molecular docking and molecular dynamics simulations with the newly published crystal structure of hST8Sia III were performed for the first time with selected ST transition state analogues. Simulations showed that these compounds could participate in many of the key interactions common with the natural donor and acceptor substrates, and reveals some key insights into the synthesis of potentially selective ST inhibitors.
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Affiliation(s)
- Christopher Dobie
- School of Chemistry, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, NSW, Australia
| | - Andrew P Montgomery
- School of Chemistry, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, NSW, Australia
| | - Rémi Szabo
- School of Chemistry, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, NSW, Australia
| | - Danielle Skropeta
- School of Chemistry, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, NSW, Australia.,Centre for Medical and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia.,Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Haibo Yu
- School of Chemistry, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, NSW, Australia.,Centre for Medical and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia.,Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, 2522, Australia
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5
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X-ray crystallographic structure of a bacterial polysialyltransferase provides insight into the biosynthesis of capsular polysialic acid. Sci Rep 2017; 7:5842. [PMID: 28724897 PMCID: PMC5517516 DOI: 10.1038/s41598-017-05627-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 05/31/2017] [Indexed: 12/21/2022] Open
Abstract
Polysialic acid (polySia) is a homopolymeric saccharide that is associated with some neuroinvasive pathogens and is found on selective cell types in their eukaryotic host. The presence of a polySia capsule on these bacterial pathogens helps with resistance to phagocytosis, cationic microbial peptides and bactericidal antibody production. The biosynthesis of bacterial polySia is catalysed by a single polysialyltransferase (PST) transferring sialic acid from a nucleotide-activated donor to a lipid-linked acceptor oligosaccharide. Here we present the X-ray structure of the bacterial PST from Mannheimia haemolytica serotype A2, thereby defining the architecture of this class of enzymes representing the GT38 family. The structure reveals a prominent electropositive groove between the two Rossmann-like domains forming the GT-B fold that is suitable for binding of polySia chain products. Complex structures of PST with a sugar donor analogue and an acceptor mimetic combined with kinetic studies of PST active site mutants provide insight into the principles of substrate binding and catalysis. Our results are the basis for a molecular understanding of polySia biosynthesis in bacteria and might assist the production of polysialylated therapeutic reagents and the development of novel antibiotics.
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McArthur JB, Yu H, Zeng J, Chen X. Converting Pasteurella multocidaα2-3-sialyltransferase 1 (PmST1) to a regioselective α2-6-sialyltransferase by saturation mutagenesis and regioselective screening. Org Biomol Chem 2017; 15:1700-1709. [PMID: 28134951 DOI: 10.1039/c6ob02702d] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A microtiter plate-based screening assay capable of determining the activity and regioselectivity of sialyltransferases was developed. This assay was used to screen two single-site saturation libraries of Pasteurella multocidaα2-3-sialyltransferase 1 (PmST1) for α2-6-sialyltransferase activity and total sialyltransferase activity. PmST1 double mutant P34H/M144L was found to be the most effective α2-6-sialyltransferase and displayed 50% reduced donor hydrolysis and 50-fold reduced sialidase activity compared to the wild-type PmST1. It retained the donor substrate promiscuity of the wild-type enzyme and was used in an efficient one-pot multienzyme (OPME) system to selectively catalyze the sialylation of the terminal galactose residue in a multigalactose-containing tetrasaccharide lacto-N-neotetraoside.
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Affiliation(s)
- John B McArthur
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA.
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Szabo R, Skropeta D. Advancement of Sialyltransferase Inhibitors: Therapeutic Challenges and Opportunities. Med Res Rev 2016; 37:219-270. [DOI: 10.1002/med.21407] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 07/14/2016] [Accepted: 08/03/2016] [Indexed: 01/06/2023]
Affiliation(s)
- Rémi Szabo
- School of Chemistry; University of Wollongong; Wollongong NSW 2522 Australia
| | - Danielle Skropeta
- School of Chemistry; University of Wollongong; Wollongong NSW 2522 Australia
- Centre for Medical & Molecular Bioscience; University of Wollongong; Wollongong NSW 2522 Australia
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Chen X, Wang Y, Ma Z, Li N, Han W, Zhang Q, Cai Y, Cheng J. Asp141 and the hydrogen-bond chain Asp141–Asn109–Asp33 are respectively essential for GT80 sialyltransferase activity and structural stability. BIOCHEMISTRY (MOSCOW) 2015; 80:1073-9. [DOI: 10.1134/s0006297915080131] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Yu CC, Withers SG. Recent Developments in Enzymatic Synthesis of Modified Sialic Acid Derivatives. Adv Synth Catal 2015. [DOI: 10.1002/adsc.201500349] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Huynh N, Li Y, Yu H, Huang S, Lau K, Chen X, Fisher AJ. Crystal structures of sialyltransferase from Photobacterium damselae. FEBS Lett 2014; 588:4720-9. [PMID: 25451227 DOI: 10.1016/j.febslet.2014.11.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Revised: 11/07/2014] [Accepted: 11/07/2014] [Indexed: 12/29/2022]
Abstract
Sialyltransferase structures fall into either GT-A or GT-B glycosyltransferase fold. Some sialyltransferases from the Photobacterium genus have been shown to contain an additional N-terminal immunoglobulin (Ig)-like domain. Photobacterium damselae α2-6-sialyltransferase has been used efficiently in enzymatic and chemoenzymatic synthesis of α2-6-linked sialosides. Here we report three crystal structures of this enzyme. Two structures with and without a donor substrate analog CMP-3F(a)Neu5Ac contain an immunoglobulin (Ig)-like domain and adopt the GT-B sialyltransferase fold. The binary structure reveals a non-productive pre-Michaelis complex, which are caused by crystal lattice contacts that prevent the large conformational changes. The third structure lacks the Ig-domain. Comparison of the three structures reveals small inherent flexibility between the two Rossmann-like domains of the GT-B fold.
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Affiliation(s)
- Nhung Huynh
- Cell Biology Graduate Program, University of California, One Shields Avenue, Davis, CA 95616, USA
| | - Yanhong Li
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA
| | - Hai Yu
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA
| | - Shengshu Huang
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA
| | - Kam Lau
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA
| | - Xi Chen
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA.
| | - Andrew J Fisher
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA; Department of Molecular and Cellular Biology, University of California, One Shields Avenue, Davis, CA 95616, USA.
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Brockhausen I. Crossroads between Bacterial and Mammalian Glycosyltransferases. Front Immunol 2014; 5:492. [PMID: 25368613 PMCID: PMC4202792 DOI: 10.3389/fimmu.2014.00492] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 09/23/2014] [Indexed: 11/26/2022] Open
Abstract
Bacterial glycosyltransferases (GT) often synthesize the same glycan linkages as mammalian GT; yet, they usually have very little sequence identity. Nevertheless, enzymatic properties, folding, substrate specificities, and catalytic mechanisms of these enzyme proteins may have significant similarity. Thus, bacterial GT can be utilized for the enzymatic synthesis of both bacterial and mammalian types of complex glycan structures. A comparison is made here between mammalian and bacterial enzymes that synthesize epitopes found in mammalian glycoproteins, and those found in the O antigens of Gram-negative bacteria. These epitopes include Thomsen–Friedenreich (TF or T) antigen, blood group O, A, and B, type 1 and 2 chains, Lewis antigens, sialylated and fucosylated structures, and polysialic acids. Many different approaches can be taken to investigate the substrate binding and catalytic mechanisms of GT, including crystal structure analyses, mutations, comparison of amino acid sequences, NMR, and mass spectrometry. Knowledge of the protein structures and functions helps to design GT for specific glycan synthesis and to develop inhibitors. The goals are to develop new strategies to reduce bacterial virulence and to synthesize vaccines and other biologically active glycan structures.
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Affiliation(s)
- Inka Brockhausen
- Department of Medicine, Queen's University , Kingston, ON , Canada ; Department of Biomedical and Molecular Sciences, Queen's University , Kingston, ON , Canada
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Albesa-Jové D, Giganti D, Jackson M, Alzari PM, Guerin ME. Structure-function relationships of membrane-associated GT-B glycosyltransferases. Glycobiology 2013; 24:108-24. [PMID: 24253765 DOI: 10.1093/glycob/cwt101] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Membrane-associated GT-B glycosyltransferases (GTs) comprise a large family of enzymes that catalyze the transfer of a sugar moiety from nucleotide-sugar donors to a wide range of membrane-associated acceptor substrates, mostly in the form of lipids and proteins. As a consequence, they generate a significant and diverse amount of glycoconjugates in biological membranes, which are particularly important in cell-cell, cell-matrix and host-pathogen recognition events. Membrane-associated GT-B enzymes display two "Rossmann-fold" domains separated by a deep cleft that includes the catalytic center. They associate permanently or temporarily to the phospholipid bilayer by a combination of hydrophobic and electrostatic interactions. They have the remarkable property to access both hydrophobic and hydrophilic substrates that reside within chemically distinct environments catalyzing their enzymatic transformations in an efficient manner. Here, we discuss the considerable progress that has been made in recent years in understanding the molecular mechanism that governs substrate and membrane recognition, and the impact of the conformational transitions undergone by these GTs during the catalytic cycle.
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Affiliation(s)
- David Albesa-Jové
- Unidad de Biofísica, Centro Mixto Consejo Superior de Investigaciones Científicas - Universidad del País Vasco/Euskal Herriko Unibertsitatea (CSIC, UPV/EHU), Barrio Sarriena s/n, Leioa, Bizkaia 48940, Spain
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Yi D, He N, Kickstein M, Metzner J, Weiß M, Berry A, Fessner W. Engineering of a Cytidine 5′‐Monophosphate‐Sialic Acid Synthetase for Improved Tolerance to Functional Sialic Acids. Adv Synth Catal 2013. [DOI: 10.1002/adsc.201300568] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Dong Yi
- Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Petersenstrasse 22, 64287 Darmstadt, Germany, Fax: (+49)‐6151‐166636
| | - Ning He
- Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Petersenstrasse 22, 64287 Darmstadt, Germany, Fax: (+49)‐6151‐166636
| | - Michael Kickstein
- Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Petersenstrasse 22, 64287 Darmstadt, Germany, Fax: (+49)‐6151‐166636
| | - Julia Metzner
- Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Petersenstrasse 22, 64287 Darmstadt, Germany, Fax: (+49)‐6151‐166636
| | - Martin Weiß
- Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Petersenstrasse 22, 64287 Darmstadt, Germany, Fax: (+49)‐6151‐166636
| | - Alan Berry
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9 JT, U.K
| | - Wolf‐Dieter Fessner
- Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Petersenstrasse 22, 64287 Darmstadt, Germany, Fax: (+49)‐6151‐166636
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Freiberger F, Böhm R, Schwarzer D, Gerardy-Schahn R, Haselhorst T, von Itzstein M. Defining a substrate-binding model of a polysialyltransferase. Chembiochem 2013; 14:1949-53. [PMID: 24009103 DOI: 10.1002/cbic.201300367] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Indexed: 11/08/2022]
Abstract
Highly disciplined transfers: Polysialyltransferases are important enzymes responsible for the biosynthesis of α-linked polysialic acids. We used a multidisciplinary approach, and propose the first substrate-binding model for a bacterial polysialyltransferase. Furthermore, we identify key amino acid residues involved in catalysis.
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Affiliation(s)
- Friedrich Freiberger
- Institute for Cellular Chemistry, Hannover Medical School, Carl-Neuberg Strasse 1, 30625 Hannover (Germany)
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Schmölzer K, Ribitsch D, Czabany T, Luley-Goedl C, Kokot D, Lyskowski A, Zitzenbacher S, Schwab H, Nidetzky B. Characterization of a multifunctional α2,3-sialyltransferase from Pasteurella dagmatis. Glycobiology 2013; 23:1293-304. [DOI: 10.1093/glycob/cwt066] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
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Sialic acid metabolism and sialyltransferases: natural functions and applications. Appl Microbiol Biotechnol 2012; 94:887-905. [PMID: 22526796 DOI: 10.1007/s00253-012-4040-1] [Citation(s) in RCA: 194] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 03/16/2012] [Accepted: 03/16/2012] [Indexed: 12/17/2022]
Abstract
Sialic acids are a family of negatively charged monosaccharides which are commonly presented as the terminal residues in glycans of the glycoconjugates on eukaryotic cell surface or as components of capsular polysaccharides or lipooligosaccharides of some pathogenic bacteria. Due to their important biological and pathological functions, the biosynthesis, activation, transfer, breaking down, and recycle of sialic acids are attracting increasing attention. The understanding of the sialic acid metabolism in eukaryotes and bacteria leads to the development of metabolic engineering approaches for elucidating the important functions of sialic acid in mammalian systems and for large-scale production of sialosides using engineered bacterial cells. As the key enzymes in biosynthesis of sialylated structures, sialyltransferases have been continuously identified from various sources and characterized. Protein crystal structures of seven sialyltransferases have been reported. Wild-type sialyltransferases and their mutants have been applied with or without other sialoside biosynthetic enzymes for producing complex sialic acid-containing oligosaccharides and glycoconjugates. This mini-review focuses on current understanding and applications of sialic acid metabolism and sialyltransferases.
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Structural and mechanistic analysis of the membrane-embedded glycosyltransferase WaaA required for lipopolysaccharide synthesis. Proc Natl Acad Sci U S A 2012; 109:6253-8. [PMID: 22474366 DOI: 10.1073/pnas.1119894109] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
WaaA is a key enzyme in the biosynthesis of LPS, a critical component of the outer envelope of Gram-negative bacteria. Embedded in the cytoplasmic face of the inner membrane, WaaA catalyzes the transfer of 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo) to the lipid A precursor of LPS. Here we present crystal structures of the free and CMP-bound forms of WaaA from Aquifex aeolicus, an ancient Gram-negative hyperthermophile. These structures reveal details of the CMP-binding site and implicate a unique sequence motif (GGS/TX(5)GXNXLE) in Kdo binding. In addition, a cluster of highly conserved amino acid residues was identified which represents the potential membrane-attachment and acceptor-substrate binding site of WaaA. A series of site-directed mutagenesis experiments revealed critical roles for glycine 30 and glutamate 31 in Kdo transfer. Our results provide the structural basis of a critical reaction in LPS biosynthesis and allowed the development of a detailed model of the catalytic mechanism of WaaA.
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Thon V, Li Y, Yu H, Lau K, Chen X. PmST3 from Pasteurella multocida encoded by Pm1174 gene is a monofunctional α2-3-sialyltransferase. Appl Microbiol Biotechnol 2011; 94:977-85. [PMID: 22075637 DOI: 10.1007/s00253-011-3676-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Revised: 10/06/2011] [Accepted: 10/26/2011] [Indexed: 01/07/2023]
Abstract
Pasteurella multocida (Pm) strain Pm70 has three putative sialyltransferase genes including Pm0188, Pm0508, and Pm1174. A Pm0188 gene homolog in Pm strain P-1059 encodes a multifunctional α2-3-sialyltransferase, PmST1, that prefers oligosaccharide acceptors. A Pm0508 gene homolog in the same strain encodes a monofunctional sialyltransferase PmST2 that prefers glycolipid acceptors. Here, we report that the third sialyltransferase from Pm (PmST3) encoded by gene Pm1174 in strain Pm70 is a monofunctional α2-3-sialyltransferase that can use both oligosaccharides and glycolipids as efficient acceptors. Despite the existence of both Pm0188 and Pm0508 gene homologs encoding PmST1 and PmST2, respectively, in Pm strain P-1059, a Pm1174 gene homolog appears to be absent from Pm strains P-1059 and P-934. PmST3 was successfully obtained by cloning and expression using a synthetic gene of Pm1174 with codons optimized for Escherichia coli expression system as the DNA template for polymer chain reactions. Truncation of 35 amino acid residues from the carboxyl terminus was shown to improve the expression of a soluble and active enzyme in E. coli as a C-His(6)-tagged fusion protein. This sialidase-free monofunctional α2-3-sialyltransferase is a useful tool for synthesizing sialylated oligosaccharides and glycolipids.
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Affiliation(s)
- Vireak Thon
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA
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Audry M, Jeanneau C, Imberty A, Harduin-Lepers A, Delannoy P, Breton C. Current trends in the structure-activity relationships of sialyltransferases. Glycobiology 2010; 21:716-26. [PMID: 21098518 DOI: 10.1093/glycob/cwq189] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Sialyltransferases (STs) represent an important group of enzymes that transfer N-acetylneuraminic acid (Neu5Ac) from cytidine monophosphate-Neu5Ac to various acceptor substrates. In higher animals, sialylated oligosaccharide structures play crucial roles in many biological processes but also in diseases, notably in microbial infection and cancer. Cell surface sialic acids have also been found in a few microorganisms, mainly pathogenic bacteria, and their presence is often associated with virulence. STs are distributed into five different families in the CAZy database (http://www.cazy.org/). On the basis of crystallographic data available for three ST families and fold recognition analysis for the two other families, STs can be grouped into two structural superfamilies that represent variations of the canonical glycosyltransferase (GT-A and GT-B) folds. These two superfamilies differ in the nature of their active site residues, notably the catalytic base (a histidine or an aspartate residue). The observed structural and functional differences strongly suggest that these two structural superfamilies have evolved independently.
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Affiliation(s)
- Magali Audry
- CERMAV-CNRS, Grenoble University, Grenoble, France
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Mine T, Kajiwara H, Murase T, Kajihara Y, Yamamoto T. An α2,3-Sialyltransferase fromPhotobacteriumsp. JT-ISH-224 TransfersN-Acetylneuraminic Acid to Both the O-2 and O-3′ Hydroxyl Groups of Lactose. J Carbohydr Chem 2010. [DOI: 10.1080/07328300903586422] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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