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Bloch S, Hager-Mair FF, Bacher J, Tomek MB, Janesch B, Andrukhov O, Schäffer C. Investigating the role of a Tannerella forsythia HtrA protease in host protein degradation and inflammatory response. FRONTIERS IN ORAL HEALTH 2024; 5:1425937. [PMID: 39035711 PMCID: PMC11257890 DOI: 10.3389/froh.2024.1425937] [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: 04/30/2024] [Accepted: 06/17/2024] [Indexed: 07/23/2024] Open
Abstract
Introduction Degradation of host proteins by bacterial proteases leads to the subversion of the host response and disruption of oral epithelial integrity, which is considered an essential factor in the progression of periodontitis. High-temperature requirement A (HtrA) protease, which is critical for bacterial survival and environmental adaptation, is found in several oral bacteria, including the periodontal pathogen Tannerella forsythia. This study investigated the proteolytic activity of HtrA from T. forsythia and its ability to modulate the host response. Methods HtrA of T. forsythia was identified bioinformatically and produced as a recombinant protein. T. forsythia mutants with depleted and restored HtrA production were constructed. The effect of T. forsythia wild-type, mutants and recombinant HtrA on the degradation of casein and E-cadherin was tested in vitro. Additionally, the responses of human gingival fibroblasts and U937 macrophages to the different HtrA-stimuli were investigated and compared to those triggered by the HtrA-deficient mutant. Results T. forsythia wild-type producing HtrA as well as the recombinant enzyme exhibited proteolytic activity towards casein and E-cadherin. No cytotoxic effect of either the wild-type, T. forsythia mutants or rHtrA on the viability of host cells was found. In hGFB and U937 macrophages, both T. forsythia species induced an inflammatory response of similar magnitude, as indicated by gene and protein expression of interleukin (IL)-1β, IL-6, IL-8, tumour necrosis factor α and monocyte chemoattractant protein (MCP)-1. Recombinant HtrA had no significant effect on the inflammatory response in hGFBs, whereas in U937 macrophages, it induced a transient inflammatory response at the early stage of infection. Conclusion HtrA of T. forsythia exhibit proteolytic activity towards the host adhesion molecule E-cadherin and has the potential to influence the host response. Its role in the progression of periodontitis needs further clarification.
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Affiliation(s)
- Susanne Bloch
- Competence Center for Periodontal Research, University Clinic of Dentistry, Medical University of Vienna, Vienna, Austria
- NanoGlycobiology Research Group, Department of Chemistry, Institute of Biochemistry, Universität für Bodenkultur Wien, Vienna, Austria
| | - Fiona F. Hager-Mair
- NanoGlycobiology Research Group, Department of Chemistry, Institute of Biochemistry, Universität für Bodenkultur Wien, Vienna, Austria
| | - Johanna Bacher
- NanoGlycobiology Research Group, Department of Chemistry, Institute of Biochemistry, Universität für Bodenkultur Wien, Vienna, Austria
- Department of Biotechnology, Institute of Bioprocess Science and Engineering, Universität für Bodenkultur Wien, Vienna, Austria
| | - Markus B. Tomek
- NanoGlycobiology Research Group, Department of Chemistry, Institute of Biochemistry, Universität für Bodenkultur Wien, Vienna, Austria
| | - Bettina Janesch
- NanoGlycobiology Research Group, Department of Chemistry, Institute of Biochemistry, Universität für Bodenkultur Wien, Vienna, Austria
| | - Oleh Andrukhov
- Competence Center for Periodontal Research, University Clinic of Dentistry, Medical University of Vienna, Vienna, Austria
| | - Christina Schäffer
- NanoGlycobiology Research Group, Department of Chemistry, Institute of Biochemistry, Universität für Bodenkultur Wien, Vienna, Austria
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2
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Zhu J, Li M, Li J, Wu J. Sialic acid metabolism of oral bacteria and its potential role in colorectal cancer and Alzheimer's disease. Carbohydr Res 2024; 541:109172. [PMID: 38823062 DOI: 10.1016/j.carres.2024.109172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Revised: 05/10/2024] [Accepted: 05/29/2024] [Indexed: 06/03/2024]
Abstract
Sialic acid metabolism in oral bacteria is a complex process involving nutrient acquisition, immune evasion, cell surface modification, and the production of metabolites that contribute to bacterial persistence and virulence in the oral cavity. In addition to causing various periodontal diseases, certain oral pathogenic bacteria, such as Porphyromonas gingivalis, Tannerella forsythia, and Fusobacterium nucleatum, can induce inflammatory reactions and influence the immunity of host cells. These associations with host cells are linked to various diseases, particularly colorectal cancer and Alzheimer's disease. Sialic acid can be found in the host oral mucosa, saliva, or food residues in the oral cavity, and it may promote the colonization of oral bacteria and contribute to disease development. This review aims to summarize the role of sialic acid metabolism in oral bacteria and discuss its effect on the pathogenesis of colorectal cancer and Alzheimer's disease.
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Affiliation(s)
- Jiao Zhu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Mengyang Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Jinfang Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Jianrong Wu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China.
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Walklett AJ, Flack EKP, Chidwick HS, Hatton NE, Keenan T, Budhadev D, Walton J, Thomas GH, Fascione MA. The Retaining Pse5Ac7Ac Pseudaminyltransferase KpsS1 Defines a Previously Unreported glycosyltransferase family (GT118). Angew Chem Int Ed Engl 2024; 63:e202318523. [PMID: 38224120 DOI: 10.1002/anie.202318523] [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: 12/03/2023] [Revised: 01/10/2024] [Accepted: 01/12/2024] [Indexed: 01/16/2024]
Abstract
Cell surface sugar 5,7-diacetyl pseudaminic acid (Pse5Ac7Ac) is a bacterial analogue of the ubiquitous sialic acid, Neu5Ac, and contributes to the virulence of a number of multidrug resistant bacteria, including ESKAPE pathogens Pseudomonas aeruginosa, and Acinetobacter baumannii. Despite its discovery in the surface glycans of bacteria over thirty years ago, to date no glycosyltransferase enzymes (GTs) dedicated to the synthesis of a pseudaminic acid glycosidic linkage have been unequivocally characterised in vitro. Herein we demonstrate that A. baumannii KpsS1 is a dedicated pseudaminyltransferase enzyme (PseT) which constructs a Pse5Ac7Ac-α(2,6)-Glcp linkage, and proceeds with retention of anomeric configuration. We utilise this PseT activity in tandem with the biosynthetic enzymes required for CMP-Pse5Ac7Ac assembly, in a two-pot, seven enzyme synthesis of an α-linked Pse5Ac7Ac glycoside. Due to its unique activity and protein sequence, we also assign KpsS1 as the prototypical member of a previously unreported GT family (GT118).
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Affiliation(s)
| | - Emily K P Flack
- Department of Chemistry, University of York, York, YO10 5DD, UK
- Department of Biology, University of York, York, YO10 5DD, UK
| | | | | | - Tessa Keenan
- Department of Chemistry, University of York, York, YO10 5DD, UK
| | | | - Julia Walton
- Department of Chemistry, University of York, York, YO10 5DD, UK
| | - Gavin H Thomas
- Department of Biology, University of York, York, YO10 5DD, UK
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4
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Lee IM, Wu HY, Angata T, Wu SH. Bacterial pseudaminic acid binding to Siglec-10 induces a macrophage interleukin-10 response and suppresses phagocytosis. Chem Commun (Camb) 2024; 60:2930-2933. [PMID: 38372418 DOI: 10.1039/d4cc00077c] [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: 02/20/2024]
Abstract
Pseudaminic acid (Pse) on pathogenic bacteria exopolysaccharide engages with the sialic acid-binding immunoglobulin-type lectin (Siglec)-10 receptor on macrophages via the critical 7-N-acetyl group. This binding stimulates macrophages to secrete interleukin 10 that suppresses phagocytosis against bacteria, but can be reverted by blocking Pse-Siglec-10 interaction with Pse-binding protein as a promising therapy.
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Affiliation(s)
- I-Ming Lee
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, No. 70 Lien-hai Road, Kaohsiung, 804201, Taiwan
| | - Hsing-Yu Wu
- Institute of Biological Chemistry, Academia Sinica, 128 Academia Road, Section 2, Nankang, 11529, Taipei, Taiwan.
| | - Takashi Angata
- Institute of Biological Chemistry, Academia Sinica, 128 Academia Road, Section 2, Nankang, 11529, Taipei, Taiwan.
| | - Shih-Hsiung Wu
- Institute of Biological Chemistry, Academia Sinica, 128 Academia Road, Section 2, Nankang, 11529, Taipei, Taiwan.
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5
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Kint N, Dubois T, Viollier PH. Stereoisomer-specific reprogramming of a bacterial flagellin sialyltransferase. EMBO J 2023; 42:e112880. [PMID: 36636824 PMCID: PMC9975948 DOI: 10.15252/embj.2022112880] [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: 10/20/2022] [Revised: 12/02/2022] [Accepted: 12/16/2022] [Indexed: 01/14/2023] Open
Abstract
Glycosylation of surface structures diversifies cells chemically and physically. Nucleotide-activated sialic acids commonly serve as glycosyl donors, particularly pseudaminic acid (Pse) and its stereoisomer legionaminic acid (Leg), which decorate eubacterial and archaeal surface layers or protein appendages. FlmG, a recently identified protein sialyltransferase, O-glycosylates flagellins, the subunits of the flagellar filament. We show that flagellin glycosylation and motility in Caulobacter crescentus and Brevundimonas subvibrioides is conferred by functionally insulated Pse and Leg biosynthesis pathways, respectively, and by specialized FlmG orthologs. We established a genetic glyco-profiling platform for the classification of Pse or Leg biosynthesis pathways, discovered a signature determinant of eubacterial and archaeal Leg biosynthesis, and validated it by reconstitution experiments in a heterologous host. Finally, by rewiring FlmG glycosylation using chimeras, we defined two modular determinants that govern flagellin glycosyltransferase specificity: a glycosyltransferase domain that either donates Leg or Pse and a specialized flagellin-binding domain that identifies the acceptor.
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Affiliation(s)
- Nicolas Kint
- Department of Microbiology & Molecular Medicine and Geneva Center for Inflammation Research (GCIR), Faculty of MedicineUniversity of GenevaGenèveSwitzerland
| | - Thomas Dubois
- University of Lille, CNRS, INRAE, Centrale Lille, UMR 8207‐UMET‐Unité Matériaux et TransformationsLilleFrance
| | - Patrick H Viollier
- Department of Microbiology & Molecular Medicine and Geneva Center for Inflammation Research (GCIR), Faculty of MedicineUniversity of GenevaGenèveSwitzerland
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6
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Tomás-Martínez S, Chen LM, Pabst M, Weissbrodt DG, van Loosdrecht MCM, Lin Y. Enrichment and application of extracellular nonulosonic acids containing polymers of Accumulibacter. Appl Microbiol Biotechnol 2023; 107:931-941. [PMID: 36484828 DOI: 10.1007/s00253-022-12326-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/28/2022] [Accepted: 11/30/2022] [Indexed: 12/14/2022]
Abstract
Pseudaminic and legionaminic acids are a subgroup of nonulosonic acids (NulOs) unique to bacterial species. There is a lack of advances in the study of these NulOs due to their complex synthesis and production. Recently, it was seen that "Candidatus Accumulibacter" can produce Pse or Leg analogues as part of its extracellular polymeric substances (EPS). In order to employ a "Ca. Accumulibacter" enrichment as production platform for bacterial sialic acids, it is necessary to determine which fractions of the EPS of "Ca. Accumulibacter" contain NulOs and how to enrich and/or isolate them. We extracted the EPS from granules enriched with "Ca. Accumulibcater" and used size-exclusion chromatography (SEC) to separate them into different molecular weight (MW) fractions. This separation resulted in two high molecular weight (> 5500 kDa) fractions dominated by polysaccharides, with a NulO content up to 4 times higher than the extracted EPS. This suggests that NulOs in "Ca. Accumulibacter" are likely located in high molecular weight polysaccharides. Additionally, it was seen that the extracted EPS and the NulO-rich fractions can bind and neutralize histones. This opens the possibility of EPS and NulO-rich fractions as potential source for sepsis treatment drugs. KEY POINTS: • NulOs in "Ca. Accumulibacter" are likely located in high MW polysaccharides • SEC allows to obtain high MW polysaccharide-rich fractions enriched with NulOs • EPS and the NulOs-rich fractions are a potential source for sepsis treatment drugs.
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Affiliation(s)
- Sergio Tomás-Martínez
- Department of Biotechnology, Delft University of Technology, Van Der Maasweg 9, 2629 HZ, Delft, The Netherlands.
| | - Le Min Chen
- Department of Biotechnology, Delft University of Technology, Van Der Maasweg 9, 2629 HZ, Delft, The Netherlands
| | - Martin Pabst
- Department of Biotechnology, Delft University of Technology, Van Der Maasweg 9, 2629 HZ, Delft, The Netherlands
| | - David G Weissbrodt
- Department of Biotechnology, Delft University of Technology, Van Der Maasweg 9, 2629 HZ, Delft, The Netherlands
| | - Mark C M van Loosdrecht
- Department of Biotechnology, Delft University of Technology, Van Der Maasweg 9, 2629 HZ, Delft, The Netherlands
| | - Yuemei Lin
- Department of Biotechnology, Delft University of Technology, Van Der Maasweg 9, 2629 HZ, Delft, The Netherlands
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7
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Niedzwiecka A, Pham Q, Ling CC. Regiospecific O → N Acyl Migration as a Methodology to Access l-Altropyranosides with an N2, N4-Differentiation. Org Lett 2022; 24:8667-8671. [DOI: 10.1021/acs.orglett.2c03508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Anna Niedzwiecka
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
| | - Quyen Pham
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
| | - Chang-Chun Ling
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
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8
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Chinthamani S, Settem RP, Honma K, Stafford GP, Sharma A. Tannerella forsythia strains differentially induce interferon gamma-induced protein 10 (IP-10) expression in macrophages due to lipopolysaccharide heterogeneity. Pathog Dis 2022; 80:6566341. [PMID: 35404415 PMCID: PMC9053306 DOI: 10.1093/femspd/ftac008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/18/2022] [Accepted: 04/07/2022] [Indexed: 11/12/2022] Open
Abstract
Abstract
Tannerella forsythia is strongly implicated in the development of periodontitis, an inflammatory disease that destroys the bone and soft tissues supporting the tooth. To date, the knowledge of the virulence attributes of T. forsythia species has mainly come from studies with a laboratory adapted strain (ATCC 43 037). In this study, we focused on two T. forsythia clinical isolates, UB4 and UB20, in relation to their ability to activate macrophages. We found that these clinical isolates differentially induced proinflammatory cytokine expression in macrophages. Prominently, the expression of the chemokine protein IP-10 (CXCL10) was highly induced by UB20 as compared to UB4 and the laboratory strain ATCC 43 037. Our study focused on the lipopolysaccharide component (LPS) of these strains and found that UB20 expressed a smooth-type LPS, unlike UB4 and ATCC 43 037 each of which expressed a rough-type LPS. The LPS from UB20, via activation of TLR4, was found to be a highly potent inducer of IP-10 expression via signaling through STAT1 (signal transducer and activator of transcription-1). These data suggest that pathogenicity of T. forsythia species could be strain dependent and the LPS heterogeneity associated with the clinical strains might be responsible for their pathogenic potential and severity of periodontitis.
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Affiliation(s)
| | | | | | | | - Ashu Sharma
- Oral Biology, University at Buffalo, Buffalo, NY, USA
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9
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Tomek MB, Janesch B, Braun ML, Taschner M, Figl R, Grünwald-Gruber C, Coyne MJ, Blaukopf M, Altmann F, Kosma P, Kählig H, Comstock LE, Schäffer C. A Combination of Structural, Genetic, Phenotypic and Enzymatic Analyses Reveals the Importance of a Predicted Fucosyltransferase to Protein O-Glycosylation in the Bacteroidetes. Biomolecules 2021; 11:1795. [PMID: 34944439 PMCID: PMC8698959 DOI: 10.3390/biom11121795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 11/21/2021] [Accepted: 11/23/2021] [Indexed: 12/20/2022] Open
Abstract
Diverse members of the Bacteroidetes phylum have general protein O-glycosylation systems that are essential for processes such as host colonization and pathogenesis. Here, we analyzed the function of a putative fucosyltransferase (FucT) family that is widely encoded in Bacteroidetes protein O-glycosylation genetic loci. We studied the FucT orthologs of three Bacteroidetes species-Tannerella forsythia, Bacteroides fragilis, and Pedobacter heparinus. To identify the linkage created by the FucT of B. fragilis, we elucidated the full structure of its nine-sugar O-glycan and found that l-fucose is linked β1,4 to glucose. Of the two fucose residues in the T. forsythia O-glycan, the fucose linked to the reducing-end galactose was shown by mutational analysis to be l-fucose. Despite the transfer of l-fucose to distinct hexose sugars in the B. fragilis and T. forsythia O-glycans, the FucT orthologs from B. fragilis, T. forsythia, and P. heparinus each cross-complement the B. fragilis ΔBF4306 and T. forsythia ΔTanf_01305 FucT mutants. In vitro enzymatic analyses showed relaxed acceptor specificity of the three enzymes, transferring l-fucose to various pNP-α-hexoses. Further, glycan structural analysis together with fucosidase assays indicated that the T. forsythia FucT links l-fucose α1,6 to galactose. Given the biological importance of fucosylated carbohydrates, these FucTs are promising candidates for synthetic glycobiology.
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Affiliation(s)
- Markus B. Tomek
- NanoGlycobiology Unit, Institute of Biologically Inspired Materials, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Muthgasse 11, A-1190 Vienna, Austria; (M.B.T.); (B.J.); (M.L.B.); (M.T.)
| | - Bettina Janesch
- NanoGlycobiology Unit, Institute of Biologically Inspired Materials, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Muthgasse 11, A-1190 Vienna, Austria; (M.B.T.); (B.J.); (M.L.B.); (M.T.)
| | - Matthias L. Braun
- NanoGlycobiology Unit, Institute of Biologically Inspired Materials, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Muthgasse 11, A-1190 Vienna, Austria; (M.B.T.); (B.J.); (M.L.B.); (M.T.)
| | - Manfred Taschner
- NanoGlycobiology Unit, Institute of Biologically Inspired Materials, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Muthgasse 11, A-1190 Vienna, Austria; (M.B.T.); (B.J.); (M.L.B.); (M.T.)
| | - Rudolf Figl
- Institute of Biochemistry, Department of Chemistry, Universität für Bodenkultur Wien, Muthgasse 18, A-1190 Vienna, Austria; (R.F.); (C.G.-G.); (F.A.)
| | - Clemens Grünwald-Gruber
- Institute of Biochemistry, Department of Chemistry, Universität für Bodenkultur Wien, Muthgasse 18, A-1190 Vienna, Austria; (R.F.); (C.G.-G.); (F.A.)
| | - Michael J. Coyne
- Department of Microbiology and the Duchossois Family Institute, University of Chicago, KCBD, 900 E. 57th Street, Chicago, IL 60637, USA; (M.J.C.); (L.E.C.)
| | - Markus Blaukopf
- Institute of Organic Chemistry, Department of Chemistry, Universität für Bodenkultur Wien, Muthgasse 18, A-1190 Vienna, Austria; (M.B.); (P.K.)
| | - Friedrich Altmann
- Institute of Biochemistry, Department of Chemistry, Universität für Bodenkultur Wien, Muthgasse 18, A-1190 Vienna, Austria; (R.F.); (C.G.-G.); (F.A.)
| | - Paul Kosma
- Institute of Organic Chemistry, Department of Chemistry, Universität für Bodenkultur Wien, Muthgasse 18, A-1190 Vienna, Austria; (M.B.); (P.K.)
| | - Hanspeter Kählig
- Department of Organic Chemistry, Faculty of Chemistry, University of Vienna, Währinger Strasse 38, A-1090 Vienna, Austria;
| | - Laurie E. Comstock
- Department of Microbiology and the Duchossois Family Institute, University of Chicago, KCBD, 900 E. 57th Street, Chicago, IL 60637, USA; (M.J.C.); (L.E.C.)
| | - Christina Schäffer
- NanoGlycobiology Unit, Institute of Biologically Inspired Materials, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Muthgasse 11, A-1190 Vienna, Austria; (M.B.T.); (B.J.); (M.L.B.); (M.T.)
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Silva L, Grosso F, Rodrigues C, Ksiezarek M, Ramos H, Peixe L. The success of particular Acinetobacter baumannii clones: accumulating resistance and virulence inside a sugary shield. J Antimicrob Chemother 2021; 76:305-311. [PMID: 33150386 DOI: 10.1093/jac/dkaa453] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Accepted: 10/05/2020] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND In Portugal, carbapenem-resistant Acinetobacter baumannii (CRAB) has been associated with ST98, ST103 and ST208 (Oxford Scheme, Oxf) and a clone has usually been associated with a particular period of time. These clonal shifts were primarily explained by an increased antimicrobial resistance profile. Here we explore genomic and biochemical differences among these and more recent clones, which could further explain the diversity and evolution of this species. METHODS A total of 116 CRAB isolates (2010-15), together with representatives of a previously described CRAB collection (4 isolates, 2001-06) were characterized by attenuated total reflection Fourier transform infrared spectroscopy (FTIR-ATR) and MLST. Representatives of different FTIR-ATR/MLST clusters were selected for WGS (n = 13), which allowed the in silico extraction of resistance and virulence genes, capsule locus and SNP analysis. RESULTS A. baumannii clonal shifts of OXA-58-producing ST103Oxf (2001-04), OXA-40-producing ST98Oxf (2002-06), OXA-23-producing ST208Oxf (2006-10) and OXA-23-producing ST218Oxf (2010-15) were accompanied by an increase in AMR genes and virulence factors. FTIR-ATR clustering was congruent with sugar composition predicted from the capsular locus: a fucosamine cluster comprising ST98Oxf, ST103Oxf and a single ST218Oxf isolate; a pseudaminic acid cluster of ST208Oxf and ST1557Oxf isolates; and legionaminic acid, resembling the sialic acid from mammalian cells, in a cluster comprising ST218Oxf isolates. The whole-genome phylogenetic tree was congruent with MLST, with isolates presenting 5-28 938 SNPs. ST208Oxf and ST218Oxf presented ∼1900 SNPs while ST103Oxf and ST1557Oxf showed a greater number of SNPs (∼28 000). CONCLUSIONS Clonal shifts of CRAB were promoted, in our country, by consecutive virulence and AMR gene pool enlargement, together with features increasing pathogen-host adaptation. Worldwide dominance of ST218Oxf is supported by the combination of high AMR and virulence levels.
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Affiliation(s)
- Liliana Silva
- UCIBIO/REQUIMTE, Laboratório de Microbiologia, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
- ESALD, Instituto Politécnico de Castelo Branco, Castelo Branco, Portugal
| | - Filipa Grosso
- UCIBIO/REQUIMTE, Laboratório de Microbiologia, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
| | - Carla Rodrigues
- UCIBIO/REQUIMTE, Laboratório de Microbiologia, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
| | - Magdalena Ksiezarek
- UCIBIO/REQUIMTE, Laboratório de Microbiologia, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
| | - Helena Ramos
- Hospital Geral de Santo António (HGSA), Porto, Portugal
| | - Luísa Peixe
- UCIBIO/REQUIMTE, Laboratório de Microbiologia, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
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Lee IM, Tu IF, Yang FL, Wu SH. Bacteriophage Tail-Spike Proteins Enable Detection of Pseudaminic-Acid-Coated Pathogenic Bacteria and Guide the Development of Antiglycan Antibodies with Cross-Species Antibacterial Activity. J Am Chem Soc 2020; 142:19446-19450. [PMID: 33166120 DOI: 10.1021/jacs.0c07314] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Pseudaminic acid (Pse), a unique carbohydrate in surface-associated glycans of pathogenic bacteria, has pivotal roles in virulence. Owing to its significant antigenicity and absence in mammals, Pse is considered an attractive target for vaccination or antibody-based therapies against bacterial infections. However, a specific and universal probe for Pse, which could also be used in immunotherapy, has not been reported. In a prior study, we used a tail spike protein from a bacteriophage (ΦAB6TSP) that digests Pse-containing exopolysaccharide (EPS) from Acinetobacter baumannii strain 54149 (Ab-54149) to form a glycoconjugate for preparing anti-Ab-54149 EPS serum. We report here that a catalytically inactive ΦAB6TSP (I-ΦAB6TSP) retains binding ability toward Pse. In addition, an I-ΦAB6TSP-DyLight-650 conjugate (Dy-I-ΦAB6TSP) was more sensitive in detecting Ab-54149 than an antibody purified from anti- Ab-54149 EPS serum. Dy-I-ΦAB6TSP also cross-reacted with other pathogenic bacteria containing Pse on their surface polysaccharides (e.g., Helicobacter pylori and Enterobacter cloacae), revealing it to be a promising probe for detecting Pse across bacterial species. We also developed a detection method that employs I-ΦAB6TSP immobilized on microtiter plate. These results suggested that the anti-Ab-54149 EPS serum would exhibit cross-reactivity to Pse on other organisms. When this was tested, this serum facilitated complement-mediated killing of H. pylori and E. cloacae, indicating its potential as a cross-species antibacterial agent. This work opens new avenues for diagnosis and treatment of multidrug resistant (MDR) bacterial infections.
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Affiliation(s)
- I-Ming Lee
- Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan
| | - I-Fan Tu
- Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan
| | - Feng-Ling Yang
- Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan
| | - Shih-Hsiung Wu
- Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan.,Department of Chemistry, National Taiwan University, Taipei 106, Taiwan
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The sps Genes Encode an Original Legionaminic Acid Pathway Required for Crust Assembly in Bacillus subtilis. mBio 2020; 11:mBio.01153-20. [PMID: 32817102 PMCID: PMC7439481 DOI: 10.1128/mbio.01153-20] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The crust is the outermost spore layer of most Bacillus strains devoid of an exosporium. This outermost layer, composed of both proteins and carbohydrates, plays a major role in the adhesion and spreading of spores into the environment. Recent studies have identified several crust proteins and have provided insights about their organization at the spore surface. However, although carbohydrates are known to participate in adhesion, little is known about their composition, structure, and localization. In this study, we showed that the spore surface of Bacillus subtilis is covered with legionaminic acid (Leg), a nine-carbon backbone nonulosonic acid known to decorate the flagellin of the human pathogens Helicobacter pylori and Campylobacter jejuni We demonstrated that the spsC, spsD, spsE, spsG, and spsM genes of Bacillus subtilis are required for Leg biosynthesis during sporulation, while the spsF gene is required for Leg transfer from the mother cell to the surface of the forespore. We also characterized the activity of SpsM and highlighted an original Leg biosynthesis pathway in B. subtilis Finally, we demonstrated that Leg is required for the assembly of the crust around the spores, and we showed that in the absence of Leg, spores were more adherent to stainless steel probably because of their reduced hydrophilicity and charge.IMPORTANCE Bacillus species are a major economic and food safety concern of the food industry because of their food spoilage-causing capability and persistence. Their persistence is mainly due to their ability to form highly resistant spores adhering to the surfaces of industrial equipment. Spores of the Bacillus subtilis group are surrounded by the crust, a superficial layer which plays a key role in their adhesion properties. However, knowledge of the composition and structure of this layer remains incomplete. Here, for the first time, we identified a nonulosonic acid (Leg) at the surfaces of bacterial spores (B. subtilis). We uncovered a novel Leg biosynthesis pathway, and we demonstrated that Leg is required for proper crust assembly. This work contributes to the description of the structure and composition of Bacillus spores which has been under way for decades, and it provides keys to understanding the importance of carbohydrates in Bacillus adhesion and persistence in the food industry.
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Flack EKP, Chidwick HS, Best M, Thomas GH, Fascione MA. Synthetic Approaches for Accessing Pseudaminic Acid (Pse) Bacterial Glycans. Chembiochem 2020; 21:1397-1407. [PMID: 31944494 DOI: 10.1002/cbic.202000019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Indexed: 12/18/2022]
Abstract
Pseudaminic acids (Pses) are a group of non-mammalian nonulosonic acids (nulOs) that have been shown to be an important virulence factor for a number of pathogenic bacteria, including emerging multidrug-resistant ESKAPE pathogens. Despite their discovery over 30 years ago, relatively little is known about the biological significance of Pse glycans compared with their sialic acid analogues, primarily due to a lack of access to the synthetically challenging Pse architecture. Recently, however, the Pse backbone has been subjected to increasing synthetic exploration by carbohydrate (bio)chemists, and the total synthesis of complex Pse glycans achieved with inspiration from the biosynthesis and subsequent detailed study of chemical glycosylation by using Pse donors. Herein, context is provided for these efforts by summarising recent synthetic approaches pioneered for accessing Pse glycans, which are set to open up this underexplored area of glycoscience to the wider scientific community.
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Affiliation(s)
- Emily K P Flack
- Department of Chemistry, University of York, Heslington Road, Heslington, York, YO10 5DD, UK
| | - Harriet S Chidwick
- Department of Chemistry, University of York, Heslington Road, Heslington, York, YO10 5DD, UK
| | - Matthew Best
- Department of Chemistry, University of York, Heslington Road, Heslington, York, YO10 5DD, UK
| | - Gavin H Thomas
- Department of Biology, University of York, Heslington Road, Heslington, York, YO10 5DD, UK
| | - Martin A Fascione
- Department of Chemistry, University of York, Heslington Road, Heslington, York, YO10 5DD, UK
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McArthur JB, Santra A, Li W, Kooner AS, Liu Z, Yu H, Chen X. L. pneumophila CMP-5,7-di-N-acetyllegionaminic acid synthetase (LpCLS)-involved chemoenzymatic synthesis of sialosides and analogues. Org Biomol Chem 2020; 18:738-744. [PMID: 31912849 DOI: 10.1039/c9ob02476j] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
5,7-Di-N-acetyllegionaminic acid (Leg5,7Ac2) is a bacterial nonulosonic acid (NulO) analogue of sialic acids, an important class of monosaccharides in mammals and in some bacteria. To develop efficient one-pot multienzyme (OPME) glycosylation systems for synthesizing Leg5,7Ac2-glycosides, Legionella pneumophila cytidine 5'-monophosphate (CMP)-Leg5,7Ac2 synthetase (LpCLS) was cloned and characterized. It was successfully used in producing Leg5,7Ac2-glycosides from chemoenzymatically synthesized Leg5,7Ac2 using a one-pot two-enzyme system or from its chemically synthesized six-carbon monosaccharide precursor 2,4-diacetamido-2,4,6-trideoxymannose (6deoxyMan2,4diNAc) in a one-pot three-enzyme system. In addition, LpCLS was shown to tolerate Neu5Ac7NAc, a C9-hydroxyl analogue of Leg5,7Ac2 and also a stable analogue of 7-O-acetylneuraminic acid (Neu5,7Ac2), to allow OPME synthesis of the corresponding α2-3-linked sialosides, from chemically synthesized six-carbon monosaccharide precursor 4-N-acetyl-4-deoxy-N-acetylmannosamine (ManNAc7NAc).
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Affiliation(s)
- John B McArthur
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA.
| | - Abhishek Santra
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA.
| | - Wanqing Li
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA.
| | - Anoopjit S Kooner
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA.
| | - Ziqi Liu
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA.
| | - Hai Yu
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA.
| | - Xi Chen
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA.
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Bloch S, Tomek MB, Friedrich V, Messner P, Schäffer C. Nonulosonic acids contribute to the pathogenicity of the oral bacterium Tannerella forsythia. Interface Focus 2019; 9:20180064. [PMID: 30842870 PMCID: PMC6388019 DOI: 10.1098/rsfs.2018.0064] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/22/2018] [Indexed: 12/15/2022] Open
Abstract
Periodontitis is a polymicrobial, biofilm-caused, inflammatory disease affecting the tooth-supporting tissues. It is not only the leading cause of tooth loss worldwide, but can also impact systemic health. The development of effective treatment strategies is hampered by the complicated disease pathogenesis which is best described by a polymicrobial synergy and dysbiosis model. This model classifies the Gram-negative anaerobe Tannerella forsythia as a periodontal pathogen, making it a prime candidate for interference with the disease. Tannerella forsythia employs a protein O-glycosylation system that enables high-density display of nonulosonic acids via the bacterium's two-dimensional crystalline cell surface layer. Nonulosonic acids are sialic acid-like sugars which are well known for their pivotal biological roles. This review summarizes the current knowledge of T. forsythia's unique cell envelope with a focus on composition, biosynthesis and functional implications of the cell surface O-glycan. We have obtained evidence that glycobiology affects the bacterium's immunogenicity and capability to establish itself in the polymicrobial oral biofilm. Analysis of the genomes of different T. forsythia isolates revealed that complex protein O-glycosylation involving nonulosonic acids is a hallmark of pathogenic T. forsythia strains and, thus, constitutes a valuable target for the design of novel anti-infective strategies to combat periodontitis.
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Tomek MB, Maresch D, Windwarder M, Friedrich V, Janesch B, Fuchs K, Neumann L, Nimeth I, Zwickl NF, Dohm JC, Everest-Dass A, Kolarich D, Himmelbauer H, Altmann F, Schäffer C. A General Protein O-Glycosylation Gene Cluster Encodes the Species-Specific Glycan of the Oral Pathogen Tannerella forsythia: O-Glycan Biosynthesis and Immunological Implications. Front Microbiol 2018; 9:2008. [PMID: 30210478 PMCID: PMC6120980 DOI: 10.3389/fmicb.2018.02008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 08/09/2018] [Indexed: 12/11/2022] Open
Abstract
The cell surface of the oral pathogen Tannerella forsythia is heavily glycosylated with a unique, complex decasaccharide that is O-glycosidically linked to the bacterium’s abundant surface (S-) layer, as well as other proteins. The S-layer glycoproteins are virulence factors of T. forsythia and there is evidence that protein O-glycosylation underpins the bacterium’s pathogenicity. To elucidate the protein O-glycosylation pathway, genes suspected of encoding pathway components were first identified in the genome sequence of the ATCC 43037 type strain, revealing a 27-kb gene cluster that was shown to be polycistronic. Using a gene deletion approach targeted at predicted glycosyltransferases (Gtfs) and methyltransferases encoded in this gene cluster, in combination with mass spectrometry of the protein-released O-glycans, we show that the gene cluster encodes the species-specific part of the T. forsythia ATCC 43037 decasaccharide and that this is assembled step-wise on a pentasaccharide core. The core was previously proposed to be conserved within the Bacteroidetes phylum, to which T. forsythia is affiliated, and its biosynthesis is encoded elsewhere on the bacterial genome. Next, to assess the prevalence of protein O-glycosylation among Tannerella sp., the publicly available genome sequences of six T. forsythia strains were compared, revealing gene clusters of similar size and organization as found in the ATCC 43037 type strain. The corresponding region in the genome of a periodontal health-associated Tannerella isolate showed a different gene composition lacking most of the genes commonly found in the pathogenic strains. Finally, we investigated whether differential cell surface glycosylation impacts T. forsythia’s overall immunogenicity. Release of proinflammatory cytokines by dendritic cells (DCs) upon stimulation with defined Gtf-deficient mutants of the type strain was measured and their T cell-priming potential post-stimulation was explored. This revealed that the O-glycan is pivotal to modulating DC effector functions, with the T. forsythia-specific glycan portion suppressing and the pentasaccharide core activating a Th17 response. We conclude that complex protein O-glycosylation is a hallmark of pathogenic T. forsythia strains and propose it as a valuable target for the design of novel antimicrobials against periodontitis.
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Affiliation(s)
- Markus B Tomek
- NanoGlycobiology Unit, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Vienna, Austria
| | - Daniel Maresch
- Division of Biochemistry, Department of Chemistry, Universität für Bodenkultur Wien, Vienna, Austria
| | - Markus Windwarder
- Division of Biochemistry, Department of Chemistry, Universität für Bodenkultur Wien, Vienna, Austria
| | - Valentin Friedrich
- NanoGlycobiology Unit, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Vienna, Austria
| | - Bettina Janesch
- NanoGlycobiology Unit, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Vienna, Austria
| | - Kristina Fuchs
- NanoGlycobiology Unit, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Vienna, Austria
| | - Laura Neumann
- Division of Biochemistry, Department of Chemistry, Universität für Bodenkultur Wien, Vienna, Austria
| | - Irene Nimeth
- NanoGlycobiology Unit, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Vienna, Austria
| | - Nikolaus F Zwickl
- Bioinformatics Group, Department of Biotechnology, Universität für Bodenkultur Wien, Vienna, Austria
| | - Juliane C Dohm
- Bioinformatics Group, Department of Biotechnology, Universität für Bodenkultur Wien, Vienna, Austria
| | - Arun Everest-Dass
- Institute for Glycomics, Griffith University, Brisbane, QLD, Australia
| | - Daniel Kolarich
- Institute for Glycomics, Griffith University, Brisbane, QLD, Australia
| | - Heinz Himmelbauer
- Bioinformatics Group, Department of Biotechnology, Universität für Bodenkultur Wien, Vienna, Austria
| | - Friedrich Altmann
- Division of Biochemistry, Department of Chemistry, Universität für Bodenkultur Wien, Vienna, Austria
| | - Christina Schäffer
- NanoGlycobiology Unit, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Vienna, Austria
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Hottmann I, Mayer VMT, Tomek MB, Friedrich V, Calvert MB, Titz A, Schäffer C, Mayer C. N-Acetylmuramic Acid (MurNAc) Auxotrophy of the Oral Pathogen Tannerella forsythia: Characterization of a MurNAc Kinase and Analysis of Its Role in Cell Wall Metabolism. Front Microbiol 2018; 9:19. [PMID: 29434575 PMCID: PMC5790795 DOI: 10.3389/fmicb.2018.00019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 01/05/2018] [Indexed: 01/15/2023] Open
Abstract
Tannerella forsythia is an anaerobic, Gram-negative oral pathogen that thrives in multispecies gingival biofilms associated with periodontitis. The bacterium is auxotrophic for the commonly essential bacterial cell wall sugar N-acetylmuramic acid (MurNAc) and, thus, strictly depends on an exogenous supply of MurNAc for growth and maintenance of cell morphology. A MurNAc transporter (Tf_MurT; Tanf_08375) and an ortholog of the Escherichia coli etherase MurQ (Tf_MurQ; Tanf_08385) converting MurNAc-6-phosphate to GlcNAc-6-phosphate were recently described for T. forsythia. In between the respective genes on the T. forsythia genome, a putative kinase gene is located. In this study, the putative kinase (Tf_MurK; Tanf_08380) was produced as a recombinant protein and biochemically characterized. Kinetic studies revealed Tf_MurK to be a 6-kinase with stringent substrate specificity for MurNAc exhibiting a 6 × 104-fold higher catalytic efficiency (kcat/Km ) for MurNAc than for N-acetylglucosamine (GlcNAc) with kcat values of 10.5 s-1 and 0.1 s-1 and Km values of 200 μM and 116 mM, respectively. The enzyme kinetic data suggest that Tf_MurK is subject to substrate inhibition (Ki[S] = 4.2 mM). To assess the role of Tf_MurK in the cell wall metabolism of T. forsythia, a kinase deletion mutant (ΔTf_murK::erm) was constructed. This mutant accumulated MurNAc intracellularly in the exponential phase, indicating the capability to take up MurNAc, but inability to catabolize MurNAc. In the stationary phase, the MurNAc level was reduced in the mutant, while the level of the peptidoglycan precursor UDP-MurNAc-pentapeptide was highly elevated. Further, according to scanning electron microscopy evidence, the ΔTf_murK::erm mutant was more tolerant toward low MurNAc concentration in the medium (below 0.5 μg/ml) before transition from healthy, rod-shaped to fusiform cells occurred, while the parent strain required > 1 μg/ml MurNAc for optimal growth. These data reveal that T. forsythia readily catabolizes exogenous MurNAc but simultaneously channels a proportion of the sugar into peptidoglycan biosynthesis. Deletion of Tf_murK blocks MurNAc catabolism and allows the direction of MurNAc solely to peptidoglycan biosynthesis, resulting in a growth advantage in MurNAc-depleted medium. This work increases our understanding of the T. forsythia cell wall metabolism and may pave new routes for lead finding in the treatment of periodontitis.
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Affiliation(s)
- Isabel Hottmann
- Microbiology and Biotechnology, Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Department of Biology, Eberhard Karls Universität Tübingen, Tübingen, Germany
| | - Valentina M. T. Mayer
- NanoGlycobiology Unit, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Vienna, Austria
| | - Markus B. Tomek
- NanoGlycobiology Unit, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Vienna, Austria
| | - Valentin Friedrich
- NanoGlycobiology Unit, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Vienna, Austria
| | - Matthew B. Calvert
- Chemical Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland, Saarbrücken, Germany
- Deutsches Zentrum für Infektionsforschung, Partner Site Hannover-Braunschweig, Brunswick, Germany
- Department of Pharmacy, Saarland University, Saarbrücken, Germany
| | - Alexander Titz
- Chemical Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland, Saarbrücken, Germany
- Deutsches Zentrum für Infektionsforschung, Partner Site Hannover-Braunschweig, Brunswick, Germany
- Department of Pharmacy, Saarland University, Saarbrücken, Germany
| | - Christina Schäffer
- NanoGlycobiology Unit, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Vienna, Austria
| | - Christoph Mayer
- Microbiology and Biotechnology, Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Department of Biology, Eberhard Karls Universität Tübingen, Tübingen, Germany
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