1
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Hsu TW, Fang JM. Advances and prospects of analytic methods for bacterial transglycosylation and inhibitor discovery. Analyst 2024; 149:2204-2222. [PMID: 38517346 DOI: 10.1039/d3an01968c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2024]
Abstract
The cell wall is essential for bacteria to maintain structural rigidity and withstand external osmotic pressure. In bacteria, the cell wall is composed of peptidoglycan. Lipid II is the basic unit for constructing highly cross-linked peptidoglycan scaffolds. Transglycosylase (TGase) is the initiating enzyme in peptidoglycan synthesis that catalyzes the ligation of lipid II moieties into repeating GlcNAc-MurNAc polysaccharides, followed by transpeptidation to generate cross-linked structures. In addition to the transglycosylases in the class-A penicillin-binding proteins (aPBPs), SEDS (shape, elongation, division and sporulation) proteins are also present in most bacteria and play vital roles in cell wall renewal, elongation, and division. In this review, we focus on the latest analytical methods including the use of radioactive labeling, gel electrophoresis, mass spectrometry, fluorescence labeling, probing undecaprenyl pyrophosphate, fluorescence anisotropy, ligand-binding-induced tryptophan fluorescence quenching, and surface plasmon resonance to evaluate TGase activity in cell wall formation. This review also covers the discovery of TGase inhibitors as potential antibacterial agents. We hope that this review will give readers a better understanding of the chemistry and basic research for the development of novel antibiotics.
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Affiliation(s)
- Tse-Wei Hsu
- Department of Chemistry, National Taiwan University, Taipei 106, Taiwan.
| | - Jim-Min Fang
- Department of Chemistry, National Taiwan University, Taipei 106, Taiwan.
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2
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Zhang XL, Báti G, Li C, Guo A, Yeo C, Ding H, Pal KB, Xu Y, Qiao Y, Liu XW. GlcNAc-1,6-anhydro-MurNAc Moiety Affords Unusual Glycosyl Acceptor that Terminates Peptidoglycan Elongation. J Am Chem Soc 2024; 146:7400-7407. [PMID: 38456799 DOI: 10.1021/jacs.3c12526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2024]
Abstract
Peptidoglycan (PG), an essential exoskeletal polymer in bacteria, is a well-known antibiotic target. PG polymerization requires the action of bacterial transglycosylases (TGases), which couple the incoming glycosyl acceptor to the donor. Interfering with the TGase activity can interrupt the PG assembly. Existing TGase inhibitors like moenomycin and Lipid II analogues always occupy the TGase active sites; other strategies to interfere with proper PG elongation have not been widely exploited. Inspired by the natural 1,6-anhydro-MurNAc termini that mark the ends of PG strands in bacteria, we hypothesized that the incorporation of an anhydromuramyl-containing glycosyl acceptor by TGase into the growing PG may effectively inhibit PG elongation. To explore this possibility, we synthesized 4-O-(N-acetyl-β-d-glucosaminyl)-1,6-anhydro-N-acetyl-β-d-muramyl-l-Ala-γ-d-Glu-l-Lys-d-Ala-d-Ala, 1, within 15 steps, and demonstrated that this anhydromuropeptide and its analogue lacking the peptide, 1-deAA, were both utilized by bacterial TGase as noncanonical anhydro glycosyl acceptors in vitro. The incorporation of an anhydromuramyl moiety into PG strands by TGases afforded efficient termination of glycan chain extension. Moreover, the preliminary in vitro studies of 1-deAA against Staphylococcus aureus showed that 1-deAA served as a reasonable antimicrobial adjunct of vancomycin. These insights imply the potential application of such anhydromuropeptides as novel classes of PG-terminating inhibitors, pointing toward novel strategies in antibacterial agent development.
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Affiliation(s)
- Xiao-Lin Zhang
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore 637371, Singapore
| | - Gábor Báti
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore 637371, Singapore
| | - Chenyu Li
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore 637371, Singapore
| | - Aoxin Guo
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore 637371, Singapore
| | - Claresta Yeo
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore 637371, Singapore
| | - Han Ding
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore 637371, Singapore
| | - Kumar Bhaskar Pal
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore 637371, Singapore
| | - Yuan Xu
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore 637371, Singapore
| | - Yuan Qiao
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore 637371, Singapore
| | - Xue-Wei Liu
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore 637371, Singapore
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3
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Adamson C, Liang Y, Feng S, Ng AWR, Qiao Y. A closer look at ligand specificity for cellular activation of NOD2 with synthetic muramyl dipeptide analogues. Chem Commun (Camb) 2024; 60:2212-2215. [PMID: 38305731 DOI: 10.1039/d3cc05807g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Abstract
To further understand the specificity of muramyl dipeptide (MDP) sensing by NOD2, we evaluated the compatibility of synthetic MDP analogues for cellular uptake and NAGK phosphorylation, the pre-requisite steps of intracellular NOD2 activation. Our results revealed that these two prior steps do not confer ligand stereoselectivity; yet NAGK strictly discriminates against the disaccharide NOD2 agonists for phosphorylation in vitro, despite it being indispensable for the cellular NOD2-stimulating effects of these analogues, implying potential glycosidase cleavage as a novel intermediate step for cellular activation of NOD2.
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Affiliation(s)
- Christopher Adamson
- School of Chemistry, Chemical Engineering and Biotechnology (CCEB), Nanyang Technological University (NTU), 21 Nanyang Link, 637371, Singapore.
| | - Yaquan Liang
- School of Chemistry, Chemical Engineering and Biotechnology (CCEB), Nanyang Technological University (NTU), 21 Nanyang Link, 637371, Singapore.
| | - Shiliu Feng
- School of Chemistry, Chemical Engineering and Biotechnology (CCEB), Nanyang Technological University (NTU), 21 Nanyang Link, 637371, Singapore.
| | - Allan Wee Ren Ng
- School of Chemistry, Chemical Engineering and Biotechnology (CCEB), Nanyang Technological University (NTU), 21 Nanyang Link, 637371, Singapore.
| | - Yuan Qiao
- School of Chemistry, Chemical Engineering and Biotechnology (CCEB), Nanyang Technological University (NTU), 21 Nanyang Link, 637371, Singapore.
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4
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Karak M, Cloonan CR, Baker BR, Cochrane RVK, Cochrane SA. Optimizations of lipid II synthesis: an essential glycolipid precursor in bacterial cell wall synthesis and a validated antibiotic target. Beilstein J Org Chem 2024; 20:220-227. [PMID: 38352069 PMCID: PMC10862138 DOI: 10.3762/bjoc.20.22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 01/26/2024] [Indexed: 02/16/2024] Open
Abstract
Lipid II is an essential glycolipid found in bacteria. Accessing this valuable cell wall precursor is important both for studying cell wall synthesis and for studying/identifying novel antimicrobial compounds. Herein, we describe optimizations to the modular chemical synthesis of lipid II and unnatural analogues. In particular, the glycosylation step, a critical step in the formation of the central disaccharide unit (GlcNAc-MurNAc), was optimized. This was achieved by employing the use of glycosyl donors with diverse leaving groups. The key advantage of this approach lies in its adaptability, allowing for the generation of a wide array of analogues through the incorporation of alternative building blocks at different stages of synthesis.
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Affiliation(s)
- Milandip Karak
- School of Chemistry and Chemical Engineering, Queen's University Belfast, David Keir Building, Stranmillis Road, Belfast, BT9 5AG, UK
| | - Cian R Cloonan
- School of Chemistry and Chemical Engineering, Queen's University Belfast, David Keir Building, Stranmillis Road, Belfast, BT9 5AG, UK
| | - Brad R Baker
- School of Chemistry and Chemical Engineering, Queen's University Belfast, David Keir Building, Stranmillis Road, Belfast, BT9 5AG, UK
| | - Rachel V K Cochrane
- School of Chemistry and Chemical Engineering, Queen's University Belfast, David Keir Building, Stranmillis Road, Belfast, BT9 5AG, UK
| | - Stephen A Cochrane
- School of Chemistry and Chemical Engineering, Queen's University Belfast, David Keir Building, Stranmillis Road, Belfast, BT9 5AG, UK
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5
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Mhamane TB, Sambyal S, Vemireddy S, Paturu RSR, Katragadda SB, Syed S, Khan A, Halmuthur M SK. Design, synthesis and biological evaluation of novel lipophilic 2, 5-disubstituted tetrazole analogues of muramyl dipeptide as NOD2 agonists. Bioorg Med Chem 2023; 88-89:117296. [PMID: 37207469 DOI: 10.1016/j.bmc.2023.117296] [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: 12/08/2022] [Revised: 04/06/2023] [Accepted: 04/22/2023] [Indexed: 05/21/2023]
Abstract
A focused library of six new 2, 5-disubstituted tetrazole (2, 5-DST) analogues of N-acetylmuramyl-l-alanyl-d-isoglutamine (MDP) as potential immunomodulators were synthesized by the bioisosteric replacement of α-amide of d-isoglutamine with 5-substituted tetrazole (5-ST). Another parameter 'lipophilicity' was also considered to improve the pharmacological properties of MDP through the alkylation of 5-substituted tetrazole during synthesis. In total, six 2, 5-DST analogues of MDP were synthesized and bio-evaluated for the study of human NOD2 stimulation activity in the innate immune response. Interestingly, among the varied lengths of the alkyl chain in 2, 5-disubstituted tetrazole derivatives, the tetrazole analogues 12b bearing the -Butyl (C4) and 12c having -Octyl (C8) chain showed the best NOD2 stimulation potency equivalent with reference compound MDP. These analogues were evaluated for their adjuvanticity against dengue antigen and analogues 12b and 12c have elicited a potent humoral and cell mediated response.
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Affiliation(s)
- Tukaram B Mhamane
- Vaccine Immunology Laboratory, OSPC Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201 002, India
| | - Shainy Sambyal
- Vaccine Immunology Laboratory, OSPC Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201 002, India
| | - Sravanthi Vemireddy
- Vaccine Immunology Laboratory, OSPC Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India
| | - Rama Subba Reddy Paturu
- Vaccine Immunology Laboratory, OSPC Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201 002, India
| | - Suresh Babu Katragadda
- Center for Natural Products and Traditional Knowledge, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India
| | - Shafi Syed
- Department of Chemistry, School of Chemical and Life Sciences, Jamia Hamdard, New Delhi, India
| | - Arif Khan
- Department of Chemistry, School of Chemical and Life Sciences, Jamia Hamdard, New Delhi, India
| | - Sampath Kumar Halmuthur M
- Vaccine Immunology Laboratory, OSPC Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201 002, India.
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6
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Kwan JMC, Qiao Y. Mechanistic Insights into the Activities of Major Families of Enzymes in Bacterial Peptidoglycan Assembly and Breakdown. Chembiochem 2023; 24:e202200693. [PMID: 36715567 DOI: 10.1002/cbic.202200693] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 01/28/2023] [Accepted: 01/30/2023] [Indexed: 01/31/2023]
Abstract
Serving as an exoskeletal scaffold, peptidoglycan is a polymeric macromolecule that is essential and conserved across all bacteria, yet is absent in mammalian cells; this has made bacterial peptidoglycan a well-established excellent antibiotic target. In addition, soluble peptidoglycan fragments derived from bacteria are increasingly recognised as key signalling molecules in mediating diverse intra- and inter-species communication in nature, including in gut microbiota-host crosstalk. Each bacterial species encodes multiple redundant enzymes for key enzymatic activities involved in peptidoglycan assembly and breakdown. In this review, we discuss recent findings on the biochemical activities of major peptidoglycan enzymes, including peptidoglycan glycosyltransferases (PGT) and transpeptidases (TPs) in the final stage of peptidoglycan assembly, as well as peptidoglycan glycosidases, lytic transglycosylase (LTs), amidases, endopeptidases (EPs) and carboxypeptidases (CPs) in peptidoglycan turnover and metabolism. Biochemical characterisation of these enzymes provides valuable insights into their substrate specificity, regulation mechanisms and potential modes of inhibition.
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Affiliation(s)
- Jeric Mun Chung Kwan
- School of Chemistry, Chemical Engineering and Biotechnology (CCEB), 21 Nanyang Link, Singapore, 637371, Singapore.,LKC School of Medicine, Nanyang Technological University (NTU) Singapore, 11 Mandalay Road, Singapore, Singapore, 208232, Singapore
| | - Yuan Qiao
- School of Chemistry, Chemical Engineering and Biotechnology (CCEB), Nanyang Technological University (NTU), Singapore, 21 Nanyang Link, Singapore, 637371, Singapore
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7
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Vacariu CM, Tanner ME. Recent Advances in the Synthesis and Biological Applications of Peptidoglycan Fragments. Chemistry 2022; 28:e202200788. [PMID: 35560956 DOI: 10.1002/chem.202200788] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Indexed: 11/09/2022]
Abstract
The biosynthesis, breakdown, and modification of peptidoglycan (PG) play vital roles in both bacterial viability and in the response of human physiology to bacterial infection. Studies on PG biochemistry are hampered by the fact that PG is an inhomogeneous insoluble macromolecule. Chemical synthesis is therefore an important means to obtain PG fragments that may serve as enzyme substrates and elicitors of the human immune response. This review outlines the recent advances in the synthesis and biochemical studies of PG fragments, PG biosynthetic intermediates (such as Park's nucleotides and PG lipids), and PG breakdown products (such as muramyl dipeptides and anhydro-muramic acid-containing fragments). A rich variety of synthetic approaches has been applied to preparing such compounds since carbohydrate, peptide, and phospholipid chemical methodologies must all be applied.
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Affiliation(s)
- Condurache M Vacariu
- Department of Chemistry, University of British Columbia, V6T 1Z1, Vancouver, British Columbia, Canada
| | - Martin E Tanner
- Department of Chemistry, University of British Columbia, V6T 1Z1, Vancouver, British Columbia, Canada
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8
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Wingen LM, Braun C, Rausch M, Gross H, Schneider T, Menche D. Versatile synthesis of pathogen specific bacterial cell wall building blocks. RSC Adv 2022; 12:15046-15069. [PMID: 35702425 PMCID: PMC9115884 DOI: 10.1039/d2ra01915a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 05/05/2022] [Indexed: 11/21/2022] Open
Abstract
Full details on the design, strategies and tactics for development of a novel synthetic sequence to farnesyl lipid I and II analogs is reported. The modular route was based on a three coupling strategy involving an efficient solid phase synthesis of the elaborate peptide fragment, which proceeded with excellent yield and stereoselectivity and was efficiently applied for the convergent synthesis of 3-lipid I and II. Furthermore, the generality of this route was demonstrated by synthesis of 3-lipid I congeners that are characteristic for S. aureus and E. faecalis. All 3-lipid I and II building blocks were obtained in high purity revealing high spectroscopic resolution. A modular three coupling strategy involving a versatile solid phase peptide synthesis enables access to pathogen specific lipid analogs in high yield, revealing high spectroscopic resolution of these key bacterial cell wall building blocks.![]()
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Affiliation(s)
- Lukas Martin Wingen
- Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, D-53121 Bonn, Germany
| | - Christina Braun
- Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, D-53121 Bonn, Germany
| | - Marvin Rausch
- Institute for Pharmaceutical Microbiology, University Clinic Bonn, University of Bonn, D-53115 Bonn, Germany
- German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Germany
| | - Harald Gross
- Pharmaceutical Institute, Dept. of Pharmaceutical Biology, University of Tübingen, D-72076 Tübingen, Germany
| | - Tanja Schneider
- Institute for Pharmaceutical Microbiology, University Clinic Bonn, University of Bonn, D-53115 Bonn, Germany
| | - Dirk Menche
- Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, D-53121 Bonn, Germany
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9
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Hsu TW, Fang JM. Effective assay of bacterial transglycosylation by molecular turn-on sensing and a second-order scattering effect. Analyst 2021; 146:5843-5847. [PMID: 34570849 DOI: 10.1039/d1an00941a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Instead of using the lipid II substrate that requires prior labelling with a radioactive isotope or fluorophore to probe the formation of peptidoglycan in bacterial transglycosylation, the released undecaprenyl pyrophosphate (UPP) product is quantitatively measured either using a terpyridine-zinc fluorescence turn-on sensor or simply by the second-order scattering effect of the in situ formed UPP-calcium complex. Both the assay methods are utilized to identify moenomycin A as a potent transglycosylase inhibitor with a consistent IC50 value.
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Affiliation(s)
- Tse-Wei Hsu
- Department of Chemistry, National Taiwan University, Taipei 106, Taiwan.
| | - Jim-Min Fang
- Department of Chemistry, National Taiwan University, Taipei 106, Taiwan. .,The Genomics Research Center, Academia Sinica, Taipei 115, Taiwan
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10
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Solid-phase synthesis of fluorescent analogues of Park’s nucleotide, lipid I and lipid II. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2021.153101] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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11
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Hsu TW, Hsu HC, Chan HY, Fang JM. A Terpyridine Zinc Complex for Selective Detection of Lipid Pyrophosphates: A Model System for Monitoring Bacterial O- and N-Transglycosylations. J Org Chem 2020; 85:12747-12753. [PMID: 32885656 DOI: 10.1021/acs.joc.0c01252] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
To develop an effective method for probing O- and N-glycosyltransfer reactions that are accompanied by the release of undecaprenyl pyrophosphate, solanesyl pyrophosphate (SPP) is used as a surrogate to bind a terpyridine zinc complex (Tpy-Zn), forming a fluorescent [Tpy-Zn]-SPP complex (Kass 106,000 M-1 in EtOH-CHCl3) with 5.8 μM LOD in HEPES buffer (10 mM, pH 7.4) containing 10 mM CaCl2 and 0.08% decyl PEG, which is similar to the bioassay conditions for lipid II polymerization.
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Affiliation(s)
- Tse-Wei Hsu
- Department of Chemistry, National Taiwan University, Taipei 106, Taiwan
| | - Hsin-Chuan Hsu
- Department of Chemistry, National Taiwan University, Taipei 106, Taiwan
| | - Hsin-Yu Chan
- Department of Chemistry, National Taiwan University, Taipei 106, Taiwan
| | - Jim-Min Fang
- Department of Chemistry, National Taiwan University, Taipei 106, Taiwan.,The Genomics Research Center, Academia Sinica, Taipei 115, Taiwan
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12
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Wingen LM, Rausch M, Schneider T, Menche D. Modular Total Synthesis of Farnesyl Analogues of Cell Wall Precursors Lipid I and II Containing the Staphylococcus aureus Pentaglycine Bridge Modification. J Org Chem 2020; 85:10206-10215. [PMID: 32571025 DOI: 10.1021/acs.joc.0c01004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A scalable and modular total synthesis of 3-lipid I and 3-lipid II was accomplished by a novel route involving an efficient solid phase synthesis of the peptide fragment and an effective chemoenzymatic attachment of the second sugar moiety. The generality of this route was further documented by the synthesis of an analogue bearing the pentaglycine interpeptidic bridge modification characteristic for the human pathogen Staphylococcus aureus.
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Affiliation(s)
- Lukas M Wingen
- Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, 53121 Bonn, Germany
| | - Marvin Rausch
- Institute for Pharmaceutical Microbiology, University Clinic Bonn, University of Bonn, 53115 Bonn, Germany.,German Center for Infection Research (DZIF), partner site Bonn-Cologne, 53127 Bonn, Germany
| | - Tanja Schneider
- Institute for Pharmaceutical Microbiology, University Clinic Bonn, University of Bonn, 53115 Bonn, Germany
| | - Dirk Menche
- Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, 53121 Bonn, Germany
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13
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Wang Y, Cheong WL, Liang Z, So LY, Chan KF, So PK, Chen YW, Wong WL, Wong KY. Hydrophobic substituents on isatin derivatives enhance their inhibition against bacterial peptidoglycan glycosyltransferase activity. Bioorg Chem 2020; 97:103710. [DOI: 10.1016/j.bioorg.2020.103710] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 02/23/2020] [Accepted: 02/26/2020] [Indexed: 10/24/2022]
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14
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Cochrane SA, Lohans CT. Breaking down the cell wall: Strategies for antibiotic discovery targeting bacterial transpeptidases. Eur J Med Chem 2020; 194:112262. [PMID: 32248005 DOI: 10.1016/j.ejmech.2020.112262] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 03/18/2020] [Accepted: 03/19/2020] [Indexed: 12/14/2022]
Abstract
The enzymes involved in bacterial cell wall synthesis are established antibiotic targets, and continue to be a central focus for antibiotic development. Bacterial penicillin-binding proteins (and, in some bacteria, l,d-transpeptidases) form essential peptide cross-links in the cell wall. Although the β-lactam class of antibiotics target these enzymes, bacterial resistance threatens their clinical use, and there is an urgent unmet need for new antibiotics. However, the search for new antibiotics targeting the bacterial cell wall is hindered by a number of obstacles associated with screening the enzymes involved in peptidoglycan synthesis. This review describes recent approaches for measuring the activity and inhibition of penicillin-binding proteins and l,d-transpeptidases, highlighting strategies that are poised to serve as valuable tools for high-throughput screening of transpeptidase inhibitors, supporting the development of new antibiotics.
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Affiliation(s)
- Stephen A Cochrane
- School of Chemistry and Chemical Engineering, David Keir Building, Stranmillis Road, Queen's University Belfast, Belfast, BT9 5AG, UK.
| | - Christopher T Lohans
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, K7L 3N6, Canada.
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15
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Duangthongyou T, Rattanakam R, Chainok K, Suramitr S, Tuntulani T, Wannalerse B. 5-Methyl-1,3-phenyl-ene bis-[5-(di-methyl-amino)-naphthalene-1-sulfonate]: crystal structure and DFT calculations. Acta Crystallogr E Crystallogr Commun 2019; 75:1079-1083. [PMID: 31392029 PMCID: PMC6659316 DOI: 10.1107/s2056989019009058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 06/25/2019] [Indexed: 11/29/2022]
Abstract
The title compound, C31H30N2S2O6, possesses crystallographically imposed twofold symmetry with the two C atoms of the central benzene ring and the C atom of its methyl substituent lying on the twofold rotation axis. The two dansyl groups are twisted away from the plane of methyl-phenyl bridging unit in opposite directions. The three-dimensional arrangement in the crystal is mainly stabilized by weak hydrogen bonds between the sulfonyl oxygen atoms and the hydrogen atoms from the N-methyl groups. Stacking of the dansyl group is not observed. From the DFT calculations, the HOMO-LUMO energy gap was found to be 2.99 eV and indicates n→π* and π→π* transitions within the mol-ecule.
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Affiliation(s)
- Tanwawan Duangthongyou
- Department of Chemistry and Center of Excellent for Innovation in Chemistry, Faculty of Science, Kasetsart University, Bangkok 10903, Thailand
| | - Ramida Rattanakam
- Department of Chemistry, Faculty of Science, Kasetsart University, Bangkok 10903, Thailand
| | - Kittipong Chainok
- Materials and Textile Technology, Faculty of Science, and Technology, Thammasart University, Pathum Thani 12120, Thailand
| | - Songwut Suramitr
- Center of Nanotechnology, Department of Chemistry, Faculty of Science, Kasetsart University, Bangkok 10903, Thailand
| | - Thawatchai Tuntulani
- Supramolecular Chemistry Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Boontana Wannalerse
- Department of Chemistry and Center of Excellent for Innovation in Chemistry, Faculty of Science, Kasetsart University, Bangkok 10903, Thailand
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16
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Lazor KM, Zhou J, DeMeester KE, D'Ambrosio EA, Grimes CL. Synthesis and Application of Methyl N,O-Hydroxylamine Muramyl Peptides. Chembiochem 2019; 20:1369-1375. [PMID: 30672111 DOI: 10.1002/cbic.201800731] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Indexed: 01/01/2023]
Abstract
The innate immune system's interaction with bacterial cells plays a pivotal role in a variety of human diseases. Carbohydrate units derived from a component of bacterial cell wall, peptidoglycan (PG), are known to stimulate an immune response. Nonetheless, access to modified late-stage peptidoglycan intermediates is limited due to their synthetic complexity. A method to rapidly functionalize PG fragments is needed to better understand the natural host-PG interactions. Here methyl N,O-hydroxylamine linkers are incorporated onto a synthetic PG derivative, muramyl dipeptide (MDP). The modification of MDP maintained the ability to stimulate a nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) immune response dependent on the expression of nucleotide-binding oligomerization domain-containing protein 2 (Nod2). Intrigued by this modification's maintenance of biological activity, several applications were explored. Methyl N,O-hydroxylamine MDP was amendable to N-hydroxylsuccinimide (NHS) chemistry for bioconjugation to fluorophores as well as a self-assembled monolayer for Nod2 surface plasmon resonance analysis. Finally, linker incorporation was applicable to larger PG fragments, both enzymatically generated from Escherichia coli or chemically synthesized. This methodology provides rapid access to PG probes in one step and allows for the installation of a variety of chemical handles to advance the molecular understanding of PG and the innate immune system.
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Affiliation(s)
- Klare M Lazor
- Department of Chemistry and Biochemistry, University of Delaware, 140 Brown Lab, Newark, DE, 19716, USA
| | - Junhui Zhou
- Department of Chemistry and Biochemistry, University of Delaware, 140 Brown Lab, Newark, DE, 19716, USA
| | - Kristen E DeMeester
- Department of Chemistry and Biochemistry, University of Delaware, 140 Brown Lab, Newark, DE, 19716, USA
| | - Elizabeth A D'Ambrosio
- Department of Chemistry and Biochemistry, University of Delaware, 140 Brown Lab, Newark, DE, 19716, USA
| | - Catherine L Grimes
- Department of Chemistry and Biochemistry, University of Delaware, 140 Brown Lab, Newark, DE, 19716, USA.,Department of Biological Sciences, University of Delaware, 140 Brown Lab, Newark, DE, 19716, USA
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17
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Structural analysis and probing the conformational space of dansylamide by means of gas-phase electron diffraction and quantum chemistry. Struct Chem 2018. [DOI: 10.1007/s11224-018-1108-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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18
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Lee M, Hesek D, Zajíček J, Fisher JF, Mobashery S. Synthesis and shift-reagent-assisted full NMR assignment of bacterial (Z 8,E 2,ω)-undecaprenol. Chem Commun (Camb) 2017; 53:12774-12777. [PMID: 29139490 PMCID: PMC5749266 DOI: 10.1039/c7cc06781j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The repeating isoprene unit is a fundamental biosynthetic motif. The repetitive structure presents challenges both for synthesis and for structural characterization. In this synthesis of the (Z8,E2,ω)-undecaprenol of prokaryotic glycobiology, we exemplify solutions to these challenges. Allylation of sulfone-derived carbanions controlled the stereochemistry, and its proof-of-structure was secured by Eu(hfc)3 complexation to disperse the overlaid resonances of its 1H NMR spectrum.
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Affiliation(s)
- Mijoon Lee
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA.
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19
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Chen KT, Lin CK, Guo CW, Chang YF, Hu CM, Lin HH, Lai Y, Cheng TJR, Cheng WC. Effect of the lipid II sugar moiety on bacterial transglycosylase: the 4-hydroxy epimer of lipid II is a TGase inhibitor. Chem Commun (Camb) 2017; 53:771-774. [DOI: 10.1039/c6cc07871k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Flipping of this hydroxyl group dramatically changes the molecular character from a TG substrate to inhibitor!
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Affiliation(s)
- Kuo-Ting Chen
- Genomics Research Center
- Academia Sinica
- Taipei
- Taiwan
- Department of Chemistry
| | - Cheng-Kun Lin
- Genomics Research Center
- Academia Sinica
- Taipei
- Taiwan
- Department of Chemistry
| | - Chih-Wei Guo
- Genomics Research Center
- Academia Sinica
- Taipei
- Taiwan
- Department of Chemistry
| | - Yi-Fan Chang
- Genomics Research Center
- Academia Sinica
- Taipei
- Taiwan
- Department of Chemistry
| | - Chia-Ming Hu
- Genomics Research Center
- Academia Sinica
- Taipei
- Taiwan
- Department of Chemistry
| | - Hsiao-Han Lin
- Genomics Research Center
- Academia Sinica
- Taipei
- Taiwan
- Department of Chemistry
| | - Yuting Lai
- Genomics Research Center
- Academia Sinica
- Taipei
- Taiwan
- Department of Chemistry
| | - Ting-Jen R. Cheng
- Genomics Research Center
- Academia Sinica
- Taipei
- Taiwan
- Department of Chemistry
| | - Wei-Chieh Cheng
- Genomics Research Center
- Academia Sinica
- Taipei
- Taiwan
- Department of Chemistry
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20
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Lin CK, Hou CC, Guo YY, Cheng WC. Design and Synthesis of Orthogonally Protected d- and l-β-Hydroxyenduracididines from d-lyxono-1,4-Lactone. Org Lett 2016; 18:5216-5219. [DOI: 10.1021/acs.orglett.6b02444] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Cheng-Kun Lin
- Genomics
Research Center, Academia Sinica, 128, Section 2, Academia Road, Taipei 11529, Taiwan
| | - Chung-Chien Hou
- Genomics
Research Center, Academia Sinica, 128, Section 2, Academia Road, Taipei 11529, Taiwan
| | - Yi-Yong Guo
- Genomics
Research Center, Academia Sinica, 128, Section 2, Academia Road, Taipei 11529, Taiwan
| | - Wei-Chieh Cheng
- Genomics
Research Center, Academia Sinica, 128, Section 2, Academia Road, Taipei 11529, Taiwan
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21
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Structural Investigation of Park's Nucleotide on Bacterial Translocase MraY: Discovery of Unexpected MraY Inhibitors. Sci Rep 2016; 6:31579. [PMID: 27531195 PMCID: PMC4987650 DOI: 10.1038/srep31579] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Accepted: 07/26/2016] [Indexed: 11/17/2022] Open
Abstract
Systematic structural modifications of the muramic acid, peptide, and nucleotide moieties of Park’s nucleotide were performed to investigate the substrate specificity of B. subtilis MraY (MraYBS). It was found that the simplest analogue of Park’s nucleotide only bearing the first two amino acids, l-alanine-iso-d-glutamic acid, could function as a MraYBS substrate. Also, the acid group attached to the Cα of iso-d-glutamic acid was found to play an important role for substrate activity. Epimerization of the C4-hydroxyl group of muramic acid and modification at the 5-position of the uracil in Park’s nucleotide were both found to dramatically impair their substrate activity. Unexpectedly, structural modifications on the uracil moiety changed the parent molecule from a substrate to an inhibitor, blocking the MraYBS translocation. One unoptimized inhibitor was found to have a Ki value of 4 ± 1 μM against MraYBS, more potent than tunicamycins.
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22
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Glycosyltransferases and Transpeptidases/Penicillin-Binding Proteins: Valuable Targets for New Antibacterials. Antibiotics (Basel) 2016; 5:antibiotics5010012. [PMID: 27025527 PMCID: PMC4810414 DOI: 10.3390/antibiotics5010012] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 01/27/2016] [Accepted: 02/03/2016] [Indexed: 12/29/2022] Open
Abstract
Peptidoglycan (PG) is an essential macromolecular sacculus surrounding most bacteria. It is assembled by the glycosyltransferase (GT) and transpeptidase (TP) activities of multimodular penicillin-binding proteins (PBPs) within multiprotein complex machineries. Both activities are essential for the synthesis of a functional stress-bearing PG shell. Although good progress has been made in terms of the functional and structural understanding of GT, finding a clinically useful antibiotic against them has been challenging until now. In contrast, the TP/PBP module has been successfully targeted by β-lactam derivatives, but the extensive use of these antibiotics has selected resistant bacterial strains that employ a wide variety of mechanisms to escape the lethal action of these antibiotics. In addition to traditional β-lactams, other classes of molecules (non-β-lactams) that inhibit PBPs are now emerging, opening new perspectives for tackling the resistance problem while taking advantage of these valuable targets, for which a wealth of structural and functional knowledge has been accumulated. The overall evidence shows that PBPs are part of multiprotein machineries whose activities are modulated by cofactors. Perturbation of these systems could lead to lethal effects. Developing screening strategies to take advantage of these mechanisms could lead to new inhibitors of PG assembly. In this paper, we present a general background on the GTs and TPs/PBPs, a survey of recent issues of bacterial resistance and a review of recent works describing new inhibitors of these enzymes.
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23
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Lin CK, Yun WY, Lin LT, Cheng WC. A concise approach to the synthesis of the uniqueN-mannosyld-β-hydroxyenduracididine moiety in the mannopeptimycin series of natural products. Org Biomol Chem 2016; 14:4054-60. [DOI: 10.1039/c6ob00644b] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The asymmetric synthesis of the orthogonally protectedN-mannosyld-β-hydroxyenduracididine (N-Man-d-βhEnd) is described, starting from enantiopure silylated (S)-serinol.
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Affiliation(s)
| | - Wen-Yi Yun
- Genomics Research Center
- Academia Sinica
- Taipei
- Taiwan
| | - Lin-Ting Lin
- Department of Chemistry
- National Cheng Kung University
- Tainan City
- Taiwan
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24
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Chainok K, Duangthongyou T, Tuntulani T, Chuenka A, Wannalerse B. The crystal structure of 2-[5-(di-methyl-amino)-naphthalene-1-sulfonamido]-phenyl 5-(di-methyl-amino)-naphthalene-1-sulfonate. Acta Crystallogr E Crystallogr Commun 2015; 71:o721-2. [PMID: 26594442 PMCID: PMC4647440 DOI: 10.1107/s2056989015016199] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 08/31/2015] [Indexed: 11/10/2022]
Abstract
The complete mol-ecule of the title compound, C30H29N3O5S2, is generated by a crystallographic twofold axis: the O atom and NH group attached to the central benzene ring are statistically disordered. The dihedral angle between the naphthalene ring system and the central benzene ring is 52.99 (6)°, while the pendant naphthalene ring systems subtend a dihedral angle of 68.17 (4)°. An intra-molecular C-H⋯O hydrogen bond closes an S(6) ring. In the crystal, the mol-ecules are linked by weak C-H⋯O hydrogen bonds.
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Affiliation(s)
- Kittipong Chainok
- Department of Physics, Faculty of Science and Technology, Thammasat University, Khlong Luang, Pathum Thani, 12120, Thailand
| | - Tanwawan Duangthongyou
- Department of Chemistry, Faculty of Science, Kasetsart University, Bangkok 10903, Thailand
| | - Thawatchai Tuntulani
- Supramolecular Chemistry Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Apinya Chuenka
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Kasetsart University, Bangkok 10903, Thailand
| | - Boontana Wannalerse
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Kasetsart University, Bangkok 10903, Thailand
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25
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Chen KT, Huang DY, Chiu CH, Lin WW, Liang PH, Cheng WC. Synthesis of Diverse N-Substituted Muramyl Dipeptide Derivatives and Their Use in a Study of Human NOD2 Stimulation Activity. Chemistry 2015; 21:11984-8. [PMID: 26226896 DOI: 10.1002/chem.201501557] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Indexed: 01/01/2023]
Abstract
A flexible synthetic strategy toward the preparation of diverse N-substituted muramyl dipeptides (N-substituted MDPs) from different protected monosaccharides is described. The synthetic MDPs include N-acetyl MDP and N-glycolyl MDP, known NOD2 ligands, and this methodology allows for structural variation at six positions, including the muramic acid, peptide, and N-substituted moieties. The capacity of these molecules to activate human NOD2 in the innate immune response was also investigated. It was found that addition of the methyl group at the C1 position of N-glycolyl MDP significantly enhanced the NOD2 stimulating activity.
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Affiliation(s)
- Kuo-Ting Chen
- Genomics Research Center, Academia Sinica No. 128, Academia Road Sec. 2, Nankang District, Taipei, 115 (Taiwan).,School of Pharmacy, National Taiwan University, No. 17, Xuzhou Road, Taipei 100 (Taiwan)
| | - Duen-Yi Huang
- Department of Pharmacology, National Taiwan University, No. 1, Jen-Ai Road, Sec. 1, Taipei 100 (Taiwan)
| | - Cheng-Hsin Chiu
- Genomics Research Center, Academia Sinica No. 128, Academia Road Sec. 2, Nankang District, Taipei, 115 (Taiwan)
| | - Wan-Wan Lin
- Department of Pharmacology, National Taiwan University, No. 1, Jen-Ai Road, Sec. 1, Taipei 100 (Taiwan).
| | - Pi-Hui Liang
- School of Pharmacy, National Taiwan University, No. 17, Xuzhou Road, Taipei 100 (Taiwan).
| | - Wei-Chieh Cheng
- Genomics Research Center, Academia Sinica No. 128, Academia Road Sec. 2, Nankang District, Taipei, 115 (Taiwan).
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26
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Lin CK, Chen KT, Hu CM, Yun WY, Cheng WC. Synthesis of 1-C-Glycoside-Linked Lipid II Analogues Toward Bacterial Transglycosylase Inhibition. Chemistry 2015; 21:7511-9. [PMID: 25820317 DOI: 10.1002/chem.201406629] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Indexed: 11/10/2022]
Abstract
Preparation of Lipid II analogues containing an enzymatically uncleavable 1-C-glycoside linkage between the disaccharide moiety and the pyrophosphate- or pyrophosphonate-lipid moiety is described. The synthesis of a common 1-C-vinyl disaccharide intermediate has been developed that allows easy preparation of both an elongated sugar-phosphate bond and a sugar-phosphonate moiety, which are coupled with the polyprenyl phosphate to give the desired molecules. Inhibition studies show how a subtle structural modification results in dramatically different potency toward bacterial transglycosylase (TGase), and the results identify Lipid II-C-O-PP (IC50 =25 μM) as a potential TGase inhibitor.
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Affiliation(s)
- Cheng-Kun Lin
- The Genomics Research Center, Academia Sinica, No. 128, Academia Road, Sec. 2, Nankang District, Taipei, 11529 (Taiwan), Fax: (+886) 2-27899931
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27
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Hsu CH, Schelwies M, Enck S, Huang LY, Huang SH, Chang YF, Cheng TJR, Cheng WC, Wong CH. Iminosugar C-glycoside analogues of α-D-GlcNAc-1-phosphate: synthesis and bacterial transglycosylase inhibition. J Org Chem 2014; 79:8629-37. [PMID: 25137529 PMCID: PMC4168788 DOI: 10.1021/jo501340s] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
![]()
We
herein describe the first synthesis of iminosugar C-glycosides
of α-d-GlcNAc-1-phosphate in 10 steps starting from
unprotected d-GlcNAc. A diastereoselective intramolecular
iodoamination–cyclization as the key step was employed to construct
the central piperidine ring of the iminosugar and the C-glycosidic
structure of α-d-GlcNAc. Finally, the iminosugar phosphonate
and its elongated phosphate analogue were accessed. These phosphorus-containing
iminosugars were coupled efficiently with lipophilic monophosphates
to give lipid-linked pyrophosphate derivatives, which are lipid II
mimetics endowed with potent inhibitory properties toward bacterial
transglycosylases (TGase).
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Affiliation(s)
- Che-Hsiung Hsu
- Genomics Research Center, Academica Sinica , Taipei 115, Taiwan
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28
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Galley NF, O'Reilly AM, Roper DI. Prospects for novel inhibitors of peptidoglycan transglycosylases. Bioorg Chem 2014; 55:16-26. [PMID: 24924926 PMCID: PMC4126109 DOI: 10.1016/j.bioorg.2014.05.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 05/12/2014] [Accepted: 05/12/2014] [Indexed: 01/07/2023]
Abstract
We examine key aspects of transglycosylase inhibitor design. Low to high throughput assays suitable for transglycosylase drug discovery. Existing chemical start points for transglycosylase active site targeting.
The lack of novel antimicrobial drugs under development coupled with the increasing occurrence of resistance to existing antibiotics by community and hospital acquired infections is of grave concern. The targeting of biosynthesis of the peptidoglycan component of the bacterial cell wall has proven to be clinically valuable but relatively little therapeutic development has been directed towards the transglycosylase step of this process. Advances towards the isolation of new antimicrobials that target transglycosylase activity will rely on the development of the enzymological tools required to identify and characterise novel inhibitors of these enzymes. Therefore, in this article, we review the assay methods developed for transglycosylases and review recent novel chemical inhibitors discovered in relation to both the lipidic substrates and natural product inhibitors of the transglycosylase step.
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Affiliation(s)
- Nicola F Galley
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Amy M O'Reilly
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - David I Roper
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK.
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29
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Liu F, Vijayakrishnan B, Faridmoayer A, Taylor TA, Parsons TB, Bernardes GJL, Kowarik M, Davis BG. Rationally designed short polyisoprenol-linked PglB substrates for engineered polypeptide and protein N-glycosylation. J Am Chem Soc 2013; 136:566-9. [PMID: 24377322 DOI: 10.1021/ja409409h] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The lipid carrier specificity of the protein N-glycosylation enzyme C. jejuni PglB was tested using a logical, synthetic array of natural and unnatural C10, C20, C30, and C40 polyisoprenol sugar pyrophosphates, including those bearing repeating cis-prenyl units. Unusual, short, synthetically accessible C20 prenols (nerylnerol 1d and geranylnerol 1e) were shown to be effective lipid carriers for PglB sugar substrates. Kinetic analyses for PglB revealed clear K(M)-only modulation with lipid chain length, thereby implicating successful in vitro application at appropriate concentrations. This was confirmed by optimized, efficient in vitro synthesis allowing >90% of Asn-linked β-N-GlcNAc-ylated peptide and proteins. This reveals a simple, flexible biocatalytic method for glycoconjugate synthesis using PglB N-glycosylation machinery and varied chemically synthesized glycosylation donor precursors.
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Affiliation(s)
- Feng Liu
- Department of Chemistry, Chemistry Research Laboratory, Oxford University , Oxford OX1 3TA United Kingdom
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30
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Lupoli TJ, Lebar MD, Markovski M, Bernhardt T, Kahne D, Walker S. Lipoprotein activators stimulate Escherichia coli penicillin-binding proteins by different mechanisms. J Am Chem Soc 2013; 136:52-5. [PMID: 24341982 DOI: 10.1021/ja410813j] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In Escherichia coli , the bifunctional penicillin-binding proteins (PBPs), PBP1A and PBP1B, play critical roles in the final stage of peptidoglycan (PG) biosynthesis. These synthetic enzymes each possess a PG glycosyltransferase (PGT) domain and a transpeptidase (TP) domain. Recent genetic experiments have shown that PBP1A and PBP1B each require an outer membrane lipoprotein, LpoA and LpoB, respectively, to function properly in vivo. Here, we use complementary assays to show that LpoA and LpoB each increase the PGT and TP activities of their cognate PBPs, albeit by different mechanisms. LpoA directly increases the rate of the PBP1A TP reaction, which also results in enhanced PGT activity; in contrast, LpoB directly affects PGT domain activity, resulting in enhanced TP activity. These studies demonstrate bidirectional coupling of PGT and TP domain function. Additionally, the transpeptidation assay described here can be applied to study other activators or inhibitors of the TP domain of PBPs, which are validated drug targets.
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Affiliation(s)
- Tania J Lupoli
- Department of Microbiology and Immunobiology, Harvard Medical School , Boston, Massachusetts 02115, United States
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31
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Huang SH, Wu WS, Huang LY, Huang WF, Fu WC, Chen PT, Fang JM, Cheng WC, Cheng TJR, Wong CH. New continuous fluorometric assay for bacterial transglycosylase using Förster resonance energy transfer. J Am Chem Soc 2013; 135:17078-89. [PMID: 24131464 DOI: 10.1021/ja407985m] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The emergence of antibiotic resistance has prompted scientists to search for new antibiotics. Transglycosylase (TGase) is an attractive target for new antibiotic discovery due to its location on the outer membrane of bacteria and its essential role in peptidoglycan synthesis. Though there have been a few molecules identified as TGase inhibitors in the past thirty years, none of them have been developed into antibiotics for humans. The slow pace of development is perhaps due to the lack of continuous, quantitative, and high-throughput assay available for the enzyme. Herein, we report a new continuous fluorescent assay based on Förster resonance energy transfer, using lipid II analogues with a dimethylamino-azobenzenesulfonyl quencher in the lipid chain and a coumarin fluorophore in the peptide chain. During the process of transglycosylation, the quencher-appended polyprenol is released and the fluorescence of coumarin can be detected. Using this system, the substrate specificity and affinity of lipid II analogues bearing various numbers and configurations of isoprene units were investigated. Moreover, the inhibition constants of moenomycin and two previously identified small molecules were also determined. In addition, a high-throughput screening using the new assay was conducted to identify potent TGase inhibitors from a 120,000 compound library. This new continuous fluorescent assay not only provides an efficient and convenient way to study TGase activities, but also enables the high-throughput screening of potential TGase inhibitors for antibiotic discovery.
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Affiliation(s)
- Shih-Hsien Huang
- Genomics Research Center, Academia Sinica , 128 Academia Road, Section 2, Nankang, Taipei, 115, Taiwan
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32
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Nakamura J, Yamashiro H, Miya H, Nishiguchi K, Maki H, Arimoto H. Staphylococcus aureus Penicillin-Binding Protein 2 Can Use Depsi-Lipid II Derived from Vancomycin-Resistant Strains for Cell Wall Synthesis. Chemistry 2013; 19:12104-12. [PMID: 23873669 PMCID: PMC4235313 DOI: 10.1002/chem.201301074] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Indexed: 01/16/2023]
Abstract
Vancomycin-resistant Staphylococcus aureus (S. aureus) (VRSA) uses depsipeptide-containing modified cell-wall precursors for the biosynthesis of peptidoglycan. Transglycosylase is responsible for the polymerization of the peptidoglycan, and the penicillin-binding protein 2 (PBP2) plays a major role in the polymerization among several transglycosylases of wild-type S. aureus. However, it is unclear whether VRSA processes the depsipeptide-containing peptidoglycan precursor by using PBP2. Here, we describe the total synthesis of depsi-lipid I, a cell-wall precursor of VRSA. By using this chemistry, we prepared a depsi-lipid II analogue as substrate for a cell-free transglycosylation system. The reconstituted system revealed that the PBP2 of S. aureus is able to process a depsi-lipid II intermediate as efficiently as its normal substrate. Moreover, the system was successfully used to demonstrate the difference in the mode of action of the two antibiotics moenomycin and vancomycin.
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Affiliation(s)
- Jun Nakamura
- Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577 (Japan), Fax: (+81) 0-22-217-6204
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33
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Vinnikova AN, Utkina NS, Danilov LL, Torgov VI, Druzhinina TN, Veselovskiĭ VV. [Synthesis and acceptor properties of 11-[(9'-anthracenyl)methoxy]undecyl phosphate and P1-{11-[(9'-anthracenyl)methoxy]undecyl}-P2-(alpha-D-galactopyranosyl) diphosphate in the enzymic reactions catalyzed by galactosylphosphotransferase and mannosyltransferase from Salmonella newport]. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2013; 39:99-104. [PMID: 23844511 DOI: 10.1134/s1068162013010123] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Fluorescent 11-[(9'-anthracenyl)methoxy]undecyl phosphate and P1-{11-[(9'-anthracenyl)methoxy]undecyl}-P2-(alpha-D-galactopyranosyl) diphosphate were chemically synthesized for the first time. The ability of the first compound to serve as substrate-acceptor ofgalactosyl phosphate residue and the second compound of mannosyl residue in enzymic reactions catalyzed by galactosylphosphotransferase and mannosyltransferase from Salmonella newport membrane preparation was demonstrated.
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34
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Lebar MD, Lupoli TJ, Tsukamoto H, May JM, Walker S, Kahne D. Forming cross-linked peptidoglycan from synthetic gram-negative Lipid II. J Am Chem Soc 2013; 135:4632-5. [PMID: 23480167 DOI: 10.1021/ja312510m] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The bacterial cell wall precursor, Lipid II, has a highly conserved structure among different organisms except for differences in the amino acid sequence of the peptide side chain. Here, we report an efficient and flexible synthesis of the canonical Lipid II precursor required for the assembly of Gram-negative peptidoglycan (PG). We use a rapid LC/MS assay to analyze PG glycosyltransfer (PGT) and transpeptidase (TP) activities of Escherichia coli penicillin binding proteins PBP1A and PBP1B and show that the native m-DAP residue in the peptide side chain of Lipid II is required in order for TP-catalyzed peptide cross-linking to occur in vitro. Comparison of PG produced from synthetic canonical E. coli Lipid II with PG isolated from E. coli cells demonstrates that we can produce PG in vitro that resembles native structure. This work provides the tools necessary for reconstituting cell wall synthesis, an essential cellular process and major antibiotic target, in a purified system.
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Affiliation(s)
- Matthew D Lebar
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA
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35
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Gampe CM, Tsukamoto H, Doud EH, Walker S, Kahne D. Tuning the moenomycin pharmacophore to enable discovery of bacterial cell wall synthesis inhibitors. J Am Chem Soc 2013; 135:3776-9. [PMID: 23448584 DOI: 10.1021/ja4000933] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
New antibiotic drugs need to be identified to address rapidly developing resistance of bacterial pathogens to common antibiotics. The natural antibiotic moenomycin A is the prototype for compounds that bind to bacterial peptidoglycan glycosyltransferases (PGTs) and inhibit cell wall biosynthesis, but it cannot be used as a drug. Here we report the chemoenzymatic synthesis of a fluorescently labeled, truncated analogue of moenomycin based on the minimal pharmacophore. This probe, which has optimized enzyme binding properties compared to moenomycin, was designed to identify low-micromolar inhibitors that bind to conserved features in PGT active sites. We demonstrate its use in displacement assays using PGTs from S. aureus, E. faecalis, and E. coli. 110,000 compounds were screened against S. aureus SgtB, and we identified a non-carbohydrate based compound that binds to all PGTs tested. We also show that the compound inhibits in vitro formation of peptidoglycan chains by several different PGTs. Thus, this assay enables the identification of small molecules that target PGT active sites, and may provide lead compounds for development of new antibiotics.
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Affiliation(s)
- Christian M Gampe
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA
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36
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Synthesis of a fluorescent acceptor substrate for glycosyltransferases involved in the assembly of O-antigens of enterohemorrhagic Escherichia coli O157 and O5. Carbohydr Res 2013; 366:17-24. [DOI: 10.1016/j.carres.2012.11.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Revised: 11/13/2012] [Accepted: 11/15/2012] [Indexed: 11/23/2022]
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37
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Shih HW, Chang YF, Li WJ, Meng FC, Huang CY, Ma C, Cheng TJR, Wong CH, Cheng WC. Effect of the Peptide Moiety of Lipid II on Bacterial Transglycosylase. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201204038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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38
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Shih HW, Chang YF, Li WJ, Meng FC, Huang CY, Ma C, Cheng TJR, Wong CH, Cheng WC. Effect of the peptide moiety of Lipid II on bacterial transglycosylase. Angew Chem Int Ed Engl 2012; 51:10123-6. [PMID: 22952114 DOI: 10.1002/anie.201204038] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Indexed: 11/09/2022]
Affiliation(s)
- Hao-Wei Shih
- Genomics Research Center, Academia Sinica, 128 Academia Road, Sec. 2, Taipei 115, Taiwan
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39
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Lovering AL, Safadi SS, Strynadka NCJ. Structural perspective of peptidoglycan biosynthesis and assembly. Annu Rev Biochem 2012; 81:451-78. [PMID: 22663080 DOI: 10.1146/annurev-biochem-061809-112742] [Citation(s) in RCA: 232] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The peptidoglycan biosynthetic pathway is a critical process in the bacterial cell and is exploited as a target for the design of antibiotics. This pathway culminates in the production of the peptidoglycan layer, which is composed of polymerized glycan chains with cross-linked peptide substituents. This layer forms the major structural component of the protective barrier known as the cell wall. Disruption in the assembly of the peptidoglycan layer causes a weakened cell wall and subsequent bacterial lysis. With bacteria responsible for both properly functioning human health (probiotic strains) and potentially serious illness (pathogenic strains), a delicate balance is necessary during clinical intervention. Recent research has furthered our understanding of the precise molecular structures, mechanisms of action, and functional interactions involved in peptidoglycan biosynthesis. This research is helping guide our understanding of how to capitalize on peptidoglycan-based therapeutics and, at a more fundamental level, of the complex machinery that creates this critical barrier for bacterial survival.
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Affiliation(s)
- Andrew L Lovering
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
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40
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Hesek D, Lee M, Zajíček J, Fisher JF, Mobashery S. Synthesis and NMR characterization of (Z,Z,Z,Z,E,E,ω)-heptaprenol. J Am Chem Soc 2012; 134:13881-8. [PMID: 22861066 DOI: 10.1021/ja306184m] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We describe a practical, multigram synthesis of (2Z,6Z,10Z,14Z,18E,22E)-3,7,11,15,19,23,27-heptamethyl-2,6,10,14,18,22,26-octacosaheptaen-1-ol [(Z(4),E(2),ω)-heptaprenol, 4] using the nerol-derived sulfone 8 as the key intermediate. Sulfone 8 is prepared by the literature route and is converted in five additional steps (18% yield from 8) to (Z(4),E(2),ω)-heptaprenol 4. The use of Eu(hfc)(3) as an NMR shift reagent not only enabled confirmation of the structure and stereochemistry of 4, but further enabled the structural assignment to a major side product from a failed synthetic connection. The availability by this synthesis of (Z(4),E(2),ω)-heptaprenol 4 in gram quantities will enable preparative access to key reagents for the study of the biosynthesis of the bacterial cell envelope.
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Affiliation(s)
- Dusan Hesek
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
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41
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Meng FC, Chen KT, Huang LY, Shih HW, Chang HH, Nien FY, Liang PH, Cheng TJR, Wong CH, Cheng WC. Total synthesis of polyprenyl N-glycolyl lipid II as a mycobacterial transglycosylase substrate. Org Lett 2011; 13:5306-9. [PMID: 21913698 DOI: 10.1021/ol2021687] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A feasible synthetic approach toward the Mycobacterium tuberculosis (Mtb) N-glycolyl lipid II-like molecule 1 is described. Compound 1 bears pendant undecaprenol and l-lysin moieties instead of the naturally occurring decaprenol and meso-diaminopimelic acid, which are not readily available. Functionalization of 1 with a fluorophore on the peptide side chain gave 14, which was found to be recognized as an Mtb TGase substrate. This result suggests it has tremendous utility for mechanistic studies, the characterization of mycobacterial enzymes, and mycobacterial TGase inhibitor evaluation.
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Affiliation(s)
- Fan-Chun Meng
- The Genomics Research Center, Academia Sinica, Nankang, Taipei, Taiwan
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42
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Tsukamoto H, Kahne D. N-methylimidazolium chloride-catalyzed pyrophosphate formation: application to the synthesis of Lipid I and NDP-sugar donors. Bioorg Med Chem Lett 2011; 21:5050-3. [PMID: 21592792 PMCID: PMC3156252 DOI: 10.1016/j.bmcl.2011.04.061] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Accepted: 04/13/2011] [Indexed: 10/18/2022]
Abstract
N-Methylimidazolium chloride is found to catalyze a coupling reaction between monophosphates and activated phosphorous-nitrogen intermediates such as a phosphorimidazolide and phosphoromorpholidate to form biologically important unsymmetrical pyrophosphate diesters. The catalyst is much more active, cheaper, and less explosive than 1H-tetrazole, known as the best catalyst for the pyrophosphate formation over a decade. The mild and neutral reaction conditions are compatible with allylic pyrophosphate formation in Lipid I syntheisis. (31)P NMR experiments suggest that the catalyst acts not only as an acid but also as a nucleophile to form cationic and electrophilic phosphor-N-methylimidazolide intermediates in the pyrophosphate formation.
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Affiliation(s)
- Hirokazu Tsukamoto
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138
| | - Daniel Kahne
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138
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Haines NR, VanZanten AN, Cuneo AA, Miller JR, Andrews WJ, Carlson DA, Harrington RM, Kiefer AM, Mason JD, Pigza JA, Murphree SS. A Sulfone-Based Strategy for the Preparation of 2,4-Disubstituted Furan Derivatives. J Org Chem 2011; 76:8131-7. [DOI: 10.1021/jo201529s] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nathan R. Haines
- Department of Chemistry, Allegheny College, Meadville, Pennsylvania 16335, United States
| | - Aaron N. VanZanten
- Department of Chemistry, Allegheny College, Meadville, Pennsylvania 16335, United States
| | - Anthony A. Cuneo
- Department of Chemistry, Allegheny College, Meadville, Pennsylvania 16335, United States
| | - John R. Miller
- Department of Chemistry, Allegheny College, Meadville, Pennsylvania 16335, United States
| | - William J. Andrews
- Department of Chemistry, Allegheny College, Meadville, Pennsylvania 16335, United States
| | - David A. Carlson
- Department of Chemistry, Allegheny College, Meadville, Pennsylvania 16335, United States
| | - Ryan M. Harrington
- Department of Chemistry, Allegheny College, Meadville, Pennsylvania 16335, United States
| | - Adam M. Kiefer
- Department of Chemistry, Allegheny College, Meadville, Pennsylvania 16335, United States
| | - Jeremy D. Mason
- Department of Chemistry, Allegheny College, Meadville, Pennsylvania 16335, United States
| | - Julie A. Pigza
- Department of Chemistry, Allegheny College, Meadville, Pennsylvania 16335, United States
| | - S. Shaun Murphree
- Department of Chemistry, Allegheny College, Meadville, Pennsylvania 16335, United States
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Shih HW, Chen KT, Cheng TJR, Wong CH, Cheng WC. A new synthetic approach toward bacterial transglycosylase substrates, Lipid II and Lipid IV. Org Lett 2011; 13:4600-3. [PMID: 21797279 DOI: 10.1021/ol201806d] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A new synthetic approach toward the bacterial transglycosylase substrates, Lipid II (1) and Lipid IV (2), is described. The key disaccharide was synthesized using the concept of relative reactivity value (RRV) and elaborated to Lipid II and Lipid IV by conjugation with the appropriate oligopeptides and pyrophosphate lipids. Interestingly, the results from our HPLC-based functional TGase assay suggested Lipid IV has a higher affinity for the enzyme than Lipid II.
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Affiliation(s)
- Hao-Wei Shih
- Department of Chemistry, National Taiwan University, Taipei, Taiwan
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45
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Diphosphate formation using cyanuric chloride or triisopropylbenzenesulfonyl chloride as the activating agents. Tetrahedron Lett 2011. [DOI: 10.1016/j.tetlet.2011.01.034] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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