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Membrane lipid remodeling eradicates Helicobacter pylori by manipulating the cholesteryl 6'-acylglucoside biosynthesis. J Biomed Sci 2024; 31:44. [PMID: 38685037 PMCID: PMC11057186 DOI: 10.1186/s12929-024-01031-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Accepted: 04/14/2024] [Indexed: 05/02/2024] Open
Abstract
BACKGROUND Helicobacter pylori, the main cause of various gastric diseases, infects approximately half of the human population. This pathogen is auxotrophic for cholesterol which it converts to various cholesteryl α-glucoside derivatives, including cholesteryl 6'-acyl α-glucoside (CAG). Since the related biosynthetic enzymes can be translocated to the host cells, the acyl chain of CAG likely comes from its precursor phosphatidylethanolamine (PE) in the host membranes. This work aims at examining how the acyl chain of CAG and PE inhibits the membrane functions, especially bacterial adhesion. METHODS Eleven CAGs that differ in acyl chains were used to study the membrane properties of human gastric adenocarcinoma cells (AGS cells), including lipid rafts clustering (monitored by immunofluorescence with confocal microscopy) and lateral membrane fluidity (by the fluorescence recovery after photobleaching). Cell-based and mouse models were employed to study the degree of bacterial adhesion, the analyses of which were conducted by using flow cytometry and immunofluorescence staining, respectively. The lipidomes of H. pylori, AGS cells and H. pylori-AGS co-cultures were analyzed by Ultraperformance Liquid Chromatography-Tandem Mass Spectroscopy (UPLC-MS/MS) to examine the effect of PE(10:0)2, PE(18:0)2, PE(18:3)2, or PE(22:6)2 treatments. RESULTS CAG10:0, CAG18:3 and CAG22:6 were found to cause the most adverse effect on the bacterial adhesion. Further LC-MS analysis indicated that the treatment of PE(10:0)2 resulted in dual effects to inhibit the bacterial adhesion, including the generation of CAG10:0 and significant changes in the membrane compositions. The initial (1 h) lipidome changes involved in the incorporation of 10:0 acyl chains into dihydro- and phytosphingosine derivatives and ceramides. In contrast, after 16 h, glycerophospholipids displayed obvious increase in their very long chain fatty acids, monounsaturated and polyunsaturated fatty acids that are considered to enhance membrane fluidity. CONCLUSIONS The PE(10:0)2 treatment significantly reduced bacterial adhesion in both AGS cells and mouse models. Our approach of membrane remodeling has thus shown great promise as a new anti-H. pylori therapy.
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Sulfoglycolipids and Related Analogues of Mycobacterium tuberculosis: Chemical Synthesis and Immunological Studies. ChemMedChem 2023; 18:e202300399. [PMID: 37788979 DOI: 10.1002/cmdc.202300399] [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: 07/28/2023] [Revised: 10/02/2023] [Accepted: 10/03/2023] [Indexed: 10/05/2023]
Abstract
Mycobacterium tuberculosis (Mtb) causes tuberculosis as one major threat to human health, which has been deteriorated owing to the emerging multidrug resistance. Mtb contains a complex lipophilic cell wall structure that is important for bacterial persistence. Among the lipid components, sulfoglycolipids (SGLs), known to induce immune cell responses, are composed of a trehalose core attached with a conserved sulfate group and 1-4 fatty acyl chains in an asymmetric pattern. At least one of these acyl chains is polymethylated with 3-12 methyl branches. Although Mtb SGL can be isolated from bacterial culture, resulting SGL is still a homologous mixture, impeding accurate research studies. This up-to-date review covers the chemical synthesis and immunological studies of Mtb SGLs and structural analogues, with an emphasis on the development of new glycosylation methods and the asymmetric synthesis of polymethylated scaffolds. Both are critical to advance further research on biological functions of these complicated SGLs.
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Orthogonal Glycosylation with Phosphate Acceptors for Expeditious Synthesis of Bacterial Inner Core Oligosaccharides. Chem Asian J 2023; 18:e202300424. [PMID: 37339944 DOI: 10.1002/asia.202300424] [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: 05/15/2023] [Revised: 06/15/2023] [Accepted: 06/20/2023] [Indexed: 06/22/2023]
Abstract
We report a practical one-pot glycosylation strategy for synthesis of bacterial inner core oligosaccharides that composed of unavailable L-glycero-D-manno and D-glycero-D-manno-heptopyranose components. The glycosylation method features a new orthogonal glycosylation procedure; whereby a phosphate acceptor is coupled with a thioglycosyl donor producing a disaccharide phosphate, which can be engaged in another orthogonal glycosylation procedure to couple with a thioglycosyl acceptor. The phosphate acceptors used in above one-pot procedure are directly prepared from thioglycosyl acceptors via the in-situ phosphorylation. Such phosphate acceptor preparation protocol eliminates the traditional protection and deprotection procedures. Based on the new one-pot glycosylation strategy, two partial inner core structures of Yersinia pestis lipopolysaccharide and Haemophilus ducreyi lipooligosaccharide were acquired.
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Tunable Strategy for the Asymmetric Synthesis of Sulfoglycolipids from Mycobacterium tuberculosis To Elucidate the Structure and Immunomodulatory Property Relationships. Angew Chem Int Ed Engl 2023; 62:e202212514. [PMID: 36349422 DOI: 10.1002/anie.202212514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Indexed: 11/11/2022]
Abstract
We developed a versatile asymmetric strategy to synthesize different classes of sulfoglycolipids (SGLs) from Mycobacterium tuberculosis. The strategy features the use of asymmetrically protected trehaloses, which were acquired from the glycosylation of TMS α-glucosyl acceptors with benzylidene-protected thioglucosyl donors. The positions of the protecting groups at the donors and acceptors can be fine-tuned to obtain different protecting-group patterns, which is crucial for regioselective acylation and sulfation. In addition, a chemoenzymatic strategy was established to prepare the polymethylated fatty acid building blocks. The strategy employs inexpensive lipase as a desymmetrization agent in the preparation of the starting substrate and readily available chiral oxazolidinone as a chirality-controlling agent in the construction of the polymethylated fatty acids. A subsequent investigation on the immunomodulatory properties of each class of SGLs showed how the structures of SGLs impact the host innate immunity response.
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Tunable Strategy for the Asymmetric Synthesis of Sulfoglycolipids from Mycobacterium tuberculosis To Elucidate the Structure and Immunomodulatory Property Relationships. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202212514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Metabolic Isolation, Stereochemical Determination, and Total Synthesis of Predominant Native Cholesteryl Phosphatidyl-α-glucoside from Carcinogenic Helicobacter pylori. Org Lett 2022; 24:5045-5050. [PMID: 35816729 DOI: 10.1021/acs.orglett.2c01815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report the isolation and stereochemical determination of the predominant native cholesteryl 6-O-phosphatidyl α-glucoside (CPG) from Helicobacter pylori via an integrated biological and chemical strategy. The strategy employed (i) the metabolic isolation of a CPG analogue and (ii) the enzymatic degradation of the analogue to obtain the native lactobacillic acid for the stereochemical determination. The absolute stereochemistry of the acid was found to be 11R and 12S. Using the new stereochemical data, we accomplished the total synthesis of predominant native CPG and other predominant αCG derivatives.
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Enhanced enzymatic production of cholesteryl 6'-acylglucoside impairs lysosomal degradation for the intracellular survival of Helicobacter pylori. J Biomed Sci 2021; 28:72. [PMID: 34706729 PMCID: PMC8549234 DOI: 10.1186/s12929-021-00768-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 10/08/2021] [Indexed: 01/15/2023] Open
Abstract
Background During autophagy defense against invading microbes, certain lipid types are indispensable for generating specialized membrane-bound organelles. The lipid composition of autophagosomes remains obscure, as does the issue of how specific lipids and lipid-associated enzymes participate in autophagosome formation and maturation. Helicobacter pylori is auxotrophic for cholesterol and converts cholesterol to cholesteryl glucoside derivatives, including cholesteryl 6ʹ-O-acyl-α-d-glucoside (CAG). We investigated how CAG and its biosynthetic acyltransferase assist H. pylori to escape host-cell autophagy. Methods We applied a metabolite-tagging method to obtain fluorophore-containing cholesteryl glucosides that were utilized to understand their intracellular locations. H. pylori 26695 and a cholesteryl glucosyltransferase (CGT)-deletion mutant (ΔCGT) were used as the standard strain and the negative control that contains no cholesterol-derived metabolites, respectively. Bacterial internalization and several autophagy-related assays were conducted to unravel the possible mechanism that H. pylori develops to hijack the host-cell autophagy response. Subcellular fractions of H. pylori-infected AGS cells were obtained and measured for the acyltransferase activity. Results The imaging studies of fluorophore-labeled cholesteryl glucosides pinpointed their intracellular localization in AGS cells. The result indicated that CAG enhances the internalization of H. pylori in AGS cells. Particularly, CAG, instead of CG and CPG, is able to augment the autophagy response induced by H. pylori. How CAG participates in the autophagy process is multifaceted. CAG was found to intervene in the degradation of autophagosomes and reduce lysosomal biogenesis, supporting the idea that intracellular H. pylori is harbored by autophago-lysosomes in favor of the bacterial survival. Furthermore, we performed the enzyme activity assay of subcellular fractions of H. pylori-infected AGS cells. The analysis showed that the acyltransferase is mainly distributed in autophago-lysosomal compartments. Conclusions Our results support the idea that the acyltransferase is mainly distributed in the subcellular compartment consisting of autophagosomes, late endosomes, and lysosomes, in which the acidic environment is beneficial for the maximal acyltransferase activity. The resulting elevated level of CAG can facilitate bacterial internalization, interfere with the autophagy flux, and causes reduced lysosomal biogenesis. Supplementary Information The online version contains supplementary material available at 10.1186/s12929-021-00768-w.
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Total synthesis of landomycins Q and R and related core structures for exploration of the cytotoxicity and antibacterial properties. RSC Adv 2021; 11:9426-9432. [PMID: 35423459 PMCID: PMC8695357 DOI: 10.1039/d1ra01088c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 02/23/2021] [Indexed: 12/27/2022] Open
Abstract
Herein, we report the total synthesis of landomycins Q and R as well as the aglycone core, namely anhydrolandomycinone and a related core analogue. The synthesis features an acetate-assisted arylation method for construction of the hindered B-ring in the core component and a one-pot aromatization-deiodination-denbenzylation procedure to streamline the global functional and protecting group manuipulation. Subsequent cytotoxicity and antibacterial studies revealed that the landomycin R is a potential antibacterial agent against methicillin-resistant Staphylococcus aureus.
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Cascade In Situ Phosphorylation and One-Pot Glycosylation for Rapid Synthesis of Heptose-Containing Oligosaccharides. J Org Chem 2020; 85:16060-16071. [PMID: 33236906 DOI: 10.1021/acs.joc.0c01828] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
We report a one-pot glycosylation strategy for achieving rapid syntheses of heptose (Hep)-containing oligosaccharides. The reported procedure was designed to incorporate an in situ phosphorylation step into an orthogonal one-pot glycosylation. Hep-containing oligosaccharides were assembled directly from building blocks with minimal effort expended on manipulation of protecting and aglycone leaving groups. The utility of our one-pot procedure was illustrated by synthesizing partial core oligosaccharide structure present in the lipopolysaccharide of Ralstonia solanacearum.
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Sub-stoichiometric reductive etherification of carbohydrate substrates and one-pot protecting group manipulation. Org Biomol Chem 2020; 18:3135-3141. [PMID: 32255139 DOI: 10.1039/d0ob00252f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
In this study, we report a new reductive etherification procedure for protection of carbohydrate substrates and its application for one-pot preparation of glycosyl building blocks. The reported procedure features the use of polymethylhydrosiloxane (PMHS) as a sub-stoichiometric reducing agent, which prevents the transilylation side reaction and improves the efficiency of the reductive etherification method. Application of the PMHS reductive etherification procedure for one-pot protecting group manipulation are described.
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Cholesteryl α-D-glucoside 6-acyltransferase enhances the adhesion of Helicobacter pylori to gastric epithelium. Commun Biol 2020; 3:120. [PMID: 32170208 PMCID: PMC7069968 DOI: 10.1038/s42003-020-0855-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 02/20/2020] [Indexed: 12/18/2022] Open
Abstract
Helicobacter pylori, the most common etiologic agent of gastric diseases including gastric cancer, is auxotrophic for cholesterol and has to hijack it from gastric epithelia. Upon uptake, the bacteria convert cholesterol to cholesteryl 6′-O-acyl-α-D-glucopyranoside (CAG) to promote lipid raft clustering in the host cell membranes. However, how CAG appears in the host to exert the pathogenesis still remains ambiguous. Herein we identified hp0499 to be the gene of cholesteryl α-D-glucopyranoside acyltransferase (CGAT). Together with cholesteryl glucosyltransferase (catalyzing the prior step), CGAT is secreted via outer membrane vesicles to the host cells for direct synthesis of CAG. This significantly enhances lipid rafts clustering, gathers adhesion molecules (including Lewis antigens and integrins α5, β1), and promotes more bacterial adhesion. Furthermore, the clinically used drug amiodarone was shown as a potent inhibitor of CGAT to effectively reduce the bacterial adhesion, indicating that CGAT is a potential target of therapeutic intervention. Jan et al. identify cholesteryl α-D- glucopyranoside acyltransferase as a key enzyme in Helicobacter pylori’s synthesis of cholesteryl 6’-O-acyl-α-D-glucopyranoside, which promotes bacterial adhesion. This study provides insights into the H. pylori-induced pathogenesis and therapeutic strategies against it.
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(2-Ketulosonyl)onate 2,3-O-thionocarbonate donors for the synthesis of KO and KDO α-glycosides and a one-pot glycosylation method for 2-keto acid donors. Org Chem Front 2020. [DOI: 10.1039/d0qo00630k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Bifunctional (2-ketulosonyl)onate thionocarbonates are effective donors for the synthesis of KO and KDO α-glycosides with perfect control in stereoselectivity.
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Diverse Synthesis of Natural Trehalosamines and Synthetic 1,1'-Disaccharide Aminoglycosides. Chembiochem 2019; 20:287-294. [PMID: 30421539 DOI: 10.1002/cbic.201800656] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Indexed: 11/05/2022]
Abstract
A general strategy for the diverse synthesis of ten disaccharide aminoglycosides, including natural 2-trehalosamine (1), 3-trehalosamine (2), 4-trehalosamine (3), and neotrehalosyl 3,3'-diamine (8) and synthetic aminoglycosides 4-7, 9, and 10, has been developed. The aminoglycoside compounds feature different anomeric configurations and numbers of amino groups. The key step for the synthesis was the glycosylation coupling of a stereodirecting donor with a configuration-stable TMS glycoside acceptor. Either the donor or acceptor could be substituted with an azido group. The aminoglycosides prepared in the present study were characterized by 1D and 2D NMR spectroscopy.
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A general strategy for diverse syntheses of anhydrolandomycinone, tetrangulol, and landomycinone. Chem Commun (Camb) 2018; 54:1885-1888. [DOI: 10.1039/c7cc09818a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A protecting group promoted-CH arylation strategy for the total synthesis of landomycinone and related core structures.
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Selective Detection of Shiga-like Toxin 1 from Complex Samples Using Pigeon Ovalbumin Functionalized Gold Nanoparticles as Affinity Probes. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2017; 65:4359-4365. [PMID: 28493685 DOI: 10.1021/acs.jafc.7b00863] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Escherichia coli O157:H7 is a foodborne pathogen. This bacterial strain can generate Shiga-like toxins (SLTs), which can cause serious sickness and even death. Thus, it is important to develop effective and sensitive methods that can be used to rapidly identify the presence of SLTs from complex samples. Pigeon egg white (PEW) contains abundant glycoproteins, including pigeon ovalbumin (POA) (∼60%). POA possesses Gal-α(1→4)-Gal-β(1→4)-GlcNAc termini, which can recognize the B subunits in SLT type 1 (SLT-1B). Thus, POA is a suitable probe for trapping SLT-1B. In this work, we used PEW proteins as starting materials to react with aqueous tetrachloroauric acid for generation of PEW-protein-immobilized gold nanoparticles (AuNPs@PEW) via one-pot reactions. We demonstrated that the generated AuNPs@PEW were mainly dominated by POA-immobilized Au NPs. The as-prepared AuNPs@PEW were used as affinity probes to selectively probe SLT-1B from complex cell lysates derived from E. coli O157:H7. The selective trapping step can be completed within ∼90 s under microwave heating (power = 450 W) to enrich sufficient SLT-1B for matrix-assisted laser desorption/ionization (MALDI) mass spectrometric analysis. Furthermore, this approach can be used to detect SLT-1B at a concentration as low as ∼40 pM. The feasibility of using the proposed method to selectively detect SLT-1B from ham contaminated by E. coli O157:H7 was also demonstrated.
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Unusually Stable Picoloyl-Protected Trimethylsilyl Glycosides for Nonsymmetrical 1,1'-Glycosylation and Synthesis of 1,1'-Disaccharides with Diverse Configurations. Chemistry 2017; 23:6905-6918. [PMID: 28272765 DOI: 10.1002/chem.201700785] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Indexed: 11/09/2022]
Abstract
Nonsymmetrical 1,1'-disaccharides and related derivatives constitute structural components in various glycolipids and natural products. Some of these compounds have been shown to exhibit appealing biological properties. We report a direct yet stereoselective 1,1'-glycosylation strategy for the synthesis of nonsymmetrical 1,1'-disaccharides with diverse configurations and sugar components. The strategy is based on the joined forces of a new class of configurationally stable glycoside acceptors and stereodirecting thioglycoside donors. The new glycoside acceptors feature a picoloyl (Pico) protecting group at the remote C4/C3 position that confers unusual stability on TMS glycosides under acidic conditions.
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A flexible 1,2-cis α-glycosylation strategy based on in situ adduct transformation. Org Biomol Chem 2017; 15:5345-5356. [DOI: 10.1039/c7ob00839b] [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
Towards a universal 1,2-cis α-glycosylation strategy using the joined forces of formamide and iodide nucleophile additives.
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Metabolic labelling of cholesteryl glucosides in Helicobacter pylori reveals how the uptake of human lipids enhances bacterial virulence. Chem Sci 2016; 7:6208-6216. [PMID: 30034762 PMCID: PMC6024656 DOI: 10.1039/c6sc00889e] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 05/28/2016] [Indexed: 12/30/2022] Open
Abstract
Helicobacter pylori infects approximately half of the human population and is the main cause of various gastric diseases. This pathogen is auxotrophic for cholesterol, which it converts upon uptake to various cholesteryl α-glucoside derivatives, including cholesteryl 6'-acyl and 6'-phosphatidyl α-glucosides (CAGs and CPGs). Owing to a lack of sensitive analytical methods, it is not known if CAGs and CPGs play distinct physiological roles or how the acyl chain component affects function. Herein we established a metabolite-labelling method for characterising these derivatives qualitatively and quantitatively with a femtomolar detection limit. The development generated an MS/MS database of CGds, allowing for profiling of all the cholesterol-derived metabolites. The subsequent analysis led to the unprecedented information that these bacteria acquire phospholipids from the membrane of epithelial cells for CAG biosynthesis. The resulting increase in longer or/and unsaturated CAG acyl chains helps to promote lipid raft formation and thus delivery of the virulence factor CagA into the host cell, supporting the idea that the host/pathogen interplay enhances bacterial virulence. These findings demonstrate an important connection between the chain length of CAGs and the bacterial pathogenicity.
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C6 picoloyl protection: a remote stereodirecting group for 2-deoxy-β-glycoside formation. Chem Commun (Camb) 2016; 51:5394-7. [PMID: 25470411 DOI: 10.1039/c4cc08465a] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
We reported a remote control glycosylation method using the picoloyl protecting group for 2-deoxy-β-glycosidic bond formation. The method is applicable to various 2-deoxythioglycosyl donors and the utility is illustrated by the synthesis of a deoxytrisaccharide component of landomycins.
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A concise synthesis of single components of partially sulfated oligomannans. Org Biomol Chem 2015; 13:11550-60. [PMID: 26463681 DOI: 10.1039/c5ob01786f] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A concise synthesis of single components of C2 sulfated oligomannans including trimers, tetramers, and pentamers is reported. The synthesis features the application of the DMF-modulation method for the participatory thiomannoside donors in 1,2-transα-glycosidic bond formation. The obtained oligomannans were fully characterized using (1)H, (13)C, COSY, and HSQC NMR spectroscopy.
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Magnetic Nanoparticle-Based Platform for Characterization of Shiga-like Toxin 1 from Complex Samples. Anal Chem 2015; 87:10513-20. [PMID: 26447488 DOI: 10.1021/acs.analchem.5b02712] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Foodborne illness outbreaks resulting from contamination of Escherichia coli O157:H7 remain a serious concern in food safety. E. coli O157:H7 can cause bloody diarrhea, hemolytic uremic syndrome, or even death. The pathogenicity of E. coli O157:H7 is mainly caused by the expression of Shiga-like toxins (SLTs), i.e., SLT-1 and SLT-2. SLTs are pentamers composed of a single A and five B subunits. In this study, we propose a magnetic nanoparticle (MNP)-based platform to rapidly identify SLT-1 from the complex cell lysate of E. coli O157:H7. The core of the MNPs is made of iron oxide, whereas the surface of the core is coated with a thin layer of alumina (Fe3O4@Al2O3 MNPs). The Fe3O4@Al2O3 MNPs are functionalized with pigeon ovalbumin (POA), which contains Gal-α(1→4)-Gal-β(1→4)-GlcNAc termini that can bind SLT-1B selectively. Furthermore, POA is a phosphate protein. Thus, it can be easily immobilized on the surface of the Fe3O4@Al2O3 MNPs through aluminum phosphate chelation under microwave heating within 1.5 min. The generated POA-Fe3O4@Al2O3 MNPs are capable of effectively enriching SLT-1B from complex cell lysates simply by pipetting 20 μL of the sample in and out of the tip in a vial for ∼1 min. To release SLT-1 from the MNPs, Gal-α(1→4)-Gal disaccharides were used for displacement. The released target species are sufficient to be identified by matrix-assisted laser desorption/ionization mass spectrometry. Although the sample volume used in this approach is small (20 μL) and the enrichment time is short (1 min), the selectivity of this approach toward SLT-1B is quite good. We have demonstrated the effectiveness of this approach for rapid determination of the presence of SLT-1 from complex cell lysates and ham/juice samples based on the detection of SLT-1B.
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Abstract
The major challenge in carbohydrate synthesis is stereochemical control of glycosidic bond formation. Different glycosylation methods have been developed that are based on the modulation effect of external nucleophiles. This review highlights the development, synthetic application, challenges and outlook of the modulated glycosylation methods.
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Chemical Synthesis of the O-Antigen Repeating Unit ofEscherichia coliO86 by anN-Formylmorpholine-Modulated One-Pot Glycosylation Strategy. ASIAN J ORG CHEM 2014. [DOI: 10.1002/ajoc.201402057] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Synthesis of Oligomeric Mannosides and Their Structure-Binding Relationship with Concanavalin A. Chem Asian J 2014; 9:1786-96. [DOI: 10.1002/asia.201402029] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Revised: 03/20/2014] [Indexed: 01/15/2023]
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Preparation of a protected 3-deoxy-D-manno-oct-2-ulosonate glycal donor for the synthesis of β-KDO-containing oligosaccharides. Org Lett 2014; 16:1474-7. [PMID: 24571125 DOI: 10.1021/ol500275j] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A practical method for the synthesis of KDO glycal donors was developed. The prepared KDO donors exhibited excellent disastereoselectivity of glycosylation in a CH2Cl2-CH3CN solvent mixture, which was found to be associated with the isopropylidene protection at the C-4 and C-5 hydroxyls. The synthetic use of the KDO donor was demonstrated in the preparation of β-KDO-containing oligosaccharides.
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Iterative α-Glycosylation Strategy for 2-Deoxy- and 2,6-Dideoxysugars: Application to the One-Pot Synthesis of Deoxysugar-Containing Oligosaccharides. European J Org Chem 2014. [DOI: 10.1002/ejoc.201400006] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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A general synthetic strategy and the anti-proliferation properties on prostate cancer cell lines for natural phenylethanoid glycosides. Org Biomol Chem 2014; 12:2926-37. [DOI: 10.1039/c3ob42503g] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Tuning Reactivity of Glycosyl Imidinium Intermediate for 2-Azido-2-deoxyglycosyl Donors in α-Glycosidic Bond Formation. Org Lett 2013; 15:5290-3. [DOI: 10.1021/ol402519c] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Total Synthesis of a Glycoglycerolipid fromMeiothermus taiwanensisthrough a One-Pot Glycosylation Reaction and Exploration of its Immunological Properties. Chem Asian J 2013; 8:3191-9. [DOI: 10.1002/asia.201300933] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Indexed: 11/09/2022]
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31
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Automated solution-phase synthesis of oligosaccharides via iterative electrochemical assembly of thioglycosides. Org Lett 2013; 15:4520-3. [PMID: 23947618 DOI: 10.1021/ol402034g] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A new iterative one-pot sequential method for the solution-phase synthesis of oligosaccharides has been devised on the basis of the electrochemical oxidation of a propagating thioglycoside terminus to generate the corresponding triflate, followed by the reaction with a thioglycoside building block having a free hydroxyl group. A practical automated synthesizer was developed for the method and was effectively used for assembling up to six thioglycoside building blocks to synthesize partial structures of poly-β-D-(1-6)-N-acetylglucosamine.
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32
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33
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Online monitoring of chemical reactions by contactless atmospheric pressure ionization mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2012; 47:586-590. [PMID: 22576871 DOI: 10.1002/jms.2983] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
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34
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Application of 2-Azido-2-deoxythioglycosides for β-Glycoside Formation and Oligosaccharide Synthesis. European J Org Chem 2012. [DOI: 10.1002/ejoc.201200173] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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35
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In situ formation of β-glycosyl imidinium triflate from participating thioglycosyl donors: elaboration to disarmed–armed iterative glycosylation. Chem Commun (Camb) 2012; 48:10910-2. [DOI: 10.1039/c2cc35032g] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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36
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37
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Dimethylformamide: An Unusual Glycosylation Modulator. Angew Chem Int Ed Engl 2011; 50:7315-20. [DOI: 10.1002/anie.201100076] [Citation(s) in RCA: 133] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Revised: 05/18/2011] [Indexed: 11/08/2022]
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38
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39
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Rate-Dependent Inverse-Addition β-Selective Mannosylation and Contiguous Sequential Glycosylation Involving β-Mannosidic Bond Formation. Chem Asian J 2010; 5:1152-62. [DOI: 10.1002/asia.200900765] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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40
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Ultrasonication-assisted spray ionization mass spectrometry for on-line monitoring of organic reactions. Chem Commun (Camb) 2010; 46:8347-9. [DOI: 10.1039/c0cc02629h] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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41
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Low-Concentration 1,2-transβ-Selective Glycosylation Strategy and Its Applications in Oligosaccharide Synthesis. Chemistry 2009; 15:10972-82. [DOI: 10.1002/chem.200901119] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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42
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A straightforward α-selective aromatic glycosylation and its application for stereospecific synthesis of 4-methylumbelliferyl α-T-antigen. Carbohydr Res 2009; 344:432-8. [DOI: 10.1016/j.carres.2008.12.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2008] [Revised: 12/07/2008] [Accepted: 12/11/2008] [Indexed: 11/24/2022]
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43
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Identification of Pseudomonas aeruginosa using functional magnetic nanoparticle-based affinity capture combined with MALDI MS analysis. Analyst 2009; 134:2087-94. [DOI: 10.1039/b908069d] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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44
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Identification of Essential Residues of Human α-l-Fucosidase and Tests of Its Mechanism. Biochemistry 2008; 48:110-20. [DOI: 10.1021/bi801529t] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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