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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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2
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Surface Glucan Structures in Aeromonas spp. Mar Drugs 2021; 19:md19110649. [PMID: 34822520 PMCID: PMC8625153 DOI: 10.3390/md19110649] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/17/2021] [Accepted: 11/19/2021] [Indexed: 01/24/2023] Open
Abstract
Aeromonas spp. are generally found in aquatic environments, although they have also been isolated from both fresh and processed food. These Gram-negative, rod-shaped bacteria are mostly infective to poikilothermic animals, although they are also considered opportunistic pathogens of both aquatic and terrestrial homeotherms, and some species have been associated with gastrointestinal and extraintestinal septicemic infections in humans. Among the different pathogenic factors associated with virulence, several cell-surface glucans have been shown to contribute to colonization and survival of Aeromonas pathogenic strains, in different hosts. Lipopolysaccharide (LPS), capsule and α-glucan structures, for instance, have been shown to play important roles in bacterial–host interactions related to pathogenesis, such as adherence, biofilm formation, or immune evasion. In addition, glycosylation of both polar and lateral flagella has been shown to be mandatory for flagella production and motility in different Aeromonas strains, and has also been associated with increased bacterial adhesion, biofilm formation, and induction of the host proinflammatory response. The main aspects of these structures are covered in this review.
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Lettl C, Haas R, Fischer W. Kinetics of CagA type IV secretion by Helicobacter pylori and the requirement for substrate unfolding. Mol Microbiol 2021; 116:794-807. [PMID: 34121254 DOI: 10.1111/mmi.14772] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 06/02/2021] [Accepted: 06/12/2021] [Indexed: 12/27/2022]
Abstract
Type IV secretion of effector proteins is an important principle for interaction of human pathogens with their target cells. The corresponding secretion systems may transport a multitude of effector proteins that have to be deployed in the respective spatiotemporal context, or only a single translocated protein, as in the case of the CagA effector protein produced by the human gastric pathogen Helicobacter pylori. For a more detailed analysis of the kinetics and mode of action of CagA type IV secretion by H. pylori, we describe here, a novel, highly sensitive split luciferase-based translocation reporter which can be easily adapted to different end-point or real-time measurements. Using this reporter, we showed that H. pylori cells are able to rapidly inject a limited amount of their CagA supply into cultured gastric epithelial cells. We have further employed the reporter system to address the question whether CagA has to be unfolded prior to translocation by the type IV secretion system. We showed that protein domains co-translocated with CagA as protein fusions are more readily tolerated as substrates than in other secretion systems, but also provide evidence that unfolding of effector proteins is a prerequisite for their transport.
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Affiliation(s)
- Clara Lettl
- Max von Pettenkofer Institute of Hygiene and Medical Microbiology, Medical Faculty, LMU Munich, Munich, Germany.,Partner Site Munich, German Center for Infection Research (DZIF), Munich, Germany
| | - Rainer Haas
- Max von Pettenkofer Institute of Hygiene and Medical Microbiology, Medical Faculty, LMU Munich, Munich, Germany.,Partner Site Munich, German Center for Infection Research (DZIF), Munich, Germany
| | - Wolfgang Fischer
- Max von Pettenkofer Institute of Hygiene and Medical Microbiology, Medical Faculty, LMU Munich, Munich, Germany.,Partner Site Munich, German Center for Infection Research (DZIF), Munich, Germany
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4
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Lin CSH, Chan ACK, Vermeulen J, Brockerman J, Soni AS, Tanner ME, Gaynor EC, McIntosh LP, Simorre JP, Murphy MEP. Peptidoglycan binding by a pocket on the accessory NTF2-domain of Pgp2 directs helical cell shape of Campylobacter jejuni. J Biol Chem 2021; 296:100528. [PMID: 33711341 PMCID: PMC8038945 DOI: 10.1016/j.jbc.2021.100528] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 03/01/2021] [Accepted: 03/08/2021] [Indexed: 01/25/2023] Open
Abstract
The helical morphology of Campylobacter jejuni, a bacterium involved in host gut colonization and pathogenesis in humans, is determined by the structure of the peptidoglycan (PG) layer. This structure is dictated by trimming of peptide stems by the LD-carboxypeptidase Pgp2 within the periplasm. The interaction interface between Pgp2 and PG to select sites for peptide trimming is unknown. We determined a 1.6 Å resolution crystal structure of Pgp2, which contains a conserved LD-carboxypeptidase domain and a previously uncharacterized domain with an NTF2-like fold (NTF2). We identified a pocket in the NTF2 domain formed by conserved residues and located ∼40 Å from the LD-carboxypeptidase active site. Expression of pgp2 in trans with substitutions of charged (Lys257, Lys307, Glu324) and hydrophobic residues (Phe242 and Tyr233) within the pocket did not restore helical morphology to a pgp2 deletion strain. Muropeptide analysis indicated a decrease of murotripeptides in the deletion strain expressing these mutants, suggesting reduced Pgp2 catalytic activity. Pgp2 but not the K307A mutant was pulled down by C. jejuni Δpgp2 PG sacculi, supporting a role for the pocket in PG binding. NMR spectroscopy was used to define the interaction interfaces of Pgp2 with several PG fragments, which bound to the active site within the LD-carboxypeptidase domain and the pocket of the NTF2 domain. We propose a model for Pgp2 binding to PG strands involving both the LD-carboxypeptidase domain and the accessory NTF2 domain to induce a helical cell shape.
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Affiliation(s)
- Chang Sheng-Huei Lin
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Anson C K Chan
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jenny Vermeulen
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jacob Brockerman
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Arvind S Soni
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada
| | - Martin E Tanner
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada
| | - Erin C Gaynor
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Lawrence P McIntosh
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada; Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada
| | | | - Michael E P Murphy
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada.
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5
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Forn-Cuní G, Fulton KM, Smith JC, Twine SM, Mendoza-Barberà E, Tomás JM, Merino S. Polar Flagella Glycosylation in Aeromonas: Genomic Characterization and Involvement of a Specific Glycosyltransferase (Fgi-1) in Heterogeneous Flagella Glycosylation. Front Microbiol 2021; 11:595697. [PMID: 33584564 PMCID: PMC7874193 DOI: 10.3389/fmicb.2020.595697] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 12/21/2020] [Indexed: 01/27/2023] Open
Abstract
Polar flagella from mesophilic Aeromonas strains have previously been shown to be modified with a range of glycans. Mass spectrometry studies of purified polar flagellins suggested the glycan typically includes a putative pseudaminic acid like derivative; while some strains are modified with this single monosaccharide, others modified with a heterologous glycan. In the current study, we demonstrate that genes involved in polar flagella glycosylation are clustered in highly polymorphic genomic islands flanked by pseudaminic acid biosynthetic genes (pse). Bioinformatic analysis of mesophilic Aeromonas genomes identified three types of polar flagella glycosylation islands (FGIs), denoted Group I, II and III. FGI Groups I and III are small genomic islands present in Aeromonas strains with flagellins modified with a single monosaccharide pseudaminic acid derivative. Group II were large genomic islands, present in strains found to modify polar flagellins with heterogeneous glycan moieties. Group II, in addition to pse genes, contained numerous glycosyltransferases and other biosynthetic enzymes. All Group II strains shared a common glycosyltransferase downstream of luxC that we named flagella glycosylation island 1, fgi-1, in A. piscicola AH-3. We demonstrate that Fgi-1 transfers the first sugar of the heterogeneous glycan to the pseudaminic acid derivative linked to polar flagellins and could be used as marker for polysaccharidic glycosylation of Aeromonas polar flagella.
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Affiliation(s)
- Gabriel Forn-Cuní
- Departamento de Genética, Microbiología y Estadística, Sección Microbiología, Virología y Biotecnología, Facultad de Biología, Universidad de Barcelona, Barcelona, Spain
| | - Kelly M. Fulton
- National Research Council Canada, Human Health Therapeutics Research Centre, Ottawa, ON, Canada
- Faculty of Science, Carleton University, Ottawa, ON, Canada
| | | | - Susan M. Twine
- National Research Council Canada, Human Health Therapeutics Research Centre, Ottawa, ON, Canada
- Faculty of Science, Carleton University, Ottawa, ON, Canada
| | - Elena Mendoza-Barberà
- Departamento de Genética, Microbiología y Estadística, Sección Microbiología, Virología y Biotecnología, Facultad de Biología, Universidad de Barcelona, Barcelona, Spain
| | - Juan M. Tomás
- Departamento de Genética, Microbiología y Estadística, Sección Microbiología, Virología y Biotecnología, Facultad de Biología, Universidad de Barcelona, Barcelona, Spain
| | - Susana Merino
- Departamento de Genética, Microbiología y Estadística, Sección Microbiología, Virología y Biotecnología, Facultad de Biología, Universidad de Barcelona, Barcelona, Spain
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6
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Polymorphism in Toll-Like Receptors and Helicobacter Pylori Motility in Autoimmune Atrophic Gastritis and Gastric Cancer. Cancers (Basel) 2019; 11:cancers11050648. [PMID: 31083432 PMCID: PMC6562993 DOI: 10.3390/cancers11050648] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 05/03/2019] [Accepted: 05/07/2019] [Indexed: 12/17/2022] Open
Abstract
Autoimmune atrophic gastritis (AAG) is associated with an increased risk of certain types of gastric cancer (GC). Helicobacter pylori (H. pylori) infection may have a role in the induction and/or maintenance of AAG and GC. Toll-like receptors (TLR) are essential for H. pylori recognition and subsequent innate and adaptive immunity responses. This study therefore aimed to characterize TLR polymorphisms, and features of bacterial flagellin A in samples from patients with AAG (n = 67), GC (n = 114) and healthy donors (HD; n = 97). TLR5 rs5744174 C/C genotype was associated with GC, lower IgG anti H. pylori response and a higher H. pylori flagellin A abundance and motility. In a subset of patients with AAG, H. pylori strains showed a reduction of the flagellin A abundance and a moderate motility compared with strains from GC patients, a prerequisite for active colonization of the deeper layers of the mucosa, host immune response and inflammation. TLR9 rs5743836 T allele showed an association with serum gastrin G17. In conclusion, our study suggests that alterations of flaA protein, moderate motility in H. pylori and two polymorphisms in TLR5 and TLR9 may favor the onset of AAG and GC, at least in a subset of patients. These findings corroborate the function of pathogen–host cell interactions and responses, likely influencing the pathogenetic process.
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7
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Kremer L, Taleb O, Boehm N, Mensah-Nyagan AG, Trifilieff E, de Seze J, Brun S. FTY720 controls disease severity and attenuates sciatic nerve damage in chronic experimental autoimmune neuritis. J Neuroinflammation 2019; 16:54. [PMID: 30825874 PMCID: PMC6397476 DOI: 10.1186/s12974-019-1441-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 02/22/2019] [Indexed: 12/21/2022] Open
Abstract
Background Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an autoimmune-mediated inflammatory disease of the peripheral nervous system characterized by a response directed against certain myelin proteins and for which therapies are limited. Previous studies have suggested a beneficial role of FTY720, a sphingosine 1-phosphate (S1P) receptor agonist, known to deplete lymphocytes from the peripheral blood by sequestering them into lymph nodes, in the treatment of experimental autoimmune neuritis (EAN). Therefore, we investigated whether FTY720 is also beneficial in chronic experimental autoimmune neuritis (c-EAN), a recently developed rat model mimicking human CIDP. Methods c-EAN was induced in Lewis rats by immunization with S-palm P0(180–199) peptide. Rats were treated with FTY720 (1 mg/kg) or vehicle intraperitoneally once daily from the onset of clinical signs for 18 days; clinical signs were assessed daily until 60 days post-immunization (dpi). Electrophysiological and histological features were examined at different time points. We also evaluated the serum levels of different pro- and anti-inflammatory cytokines by ELISA or flow cytometry at 18, 40, and 60 dpi. Results Our data demonstrate that FTY720 decreased the severity and abolished the chronicity of the disease in c-EAN rats. Therapeutic FTY720 treatment reversed electrophysiological and histological anomalies, suggesting that myelinated fibers were subsequently preserved, it inhibited macrophage and IL-17+ cell infiltration in PNS, and it significantly reduced circulating pro-inflammatory cytokines. Conclusions FTY720 treatment has beneficial effects on c-EAN, a new animal model mimicking human CIDP. We have shown that FTY720 is an effective immunomodulatory agent, improving the disease course of c-EAN, preserving the myelinated fibers, attenuating the axonal degeneration, and decreasing the number of infiltrated inflammatory cells in peripheral nerves. These data confirm the interest of testing FTY720 or molecules targeting S1P in human peripheral neuropathies. Electronic supplementary material The online version of this article (10.1186/s12974-019-1441-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Laurent Kremer
- Biopathologie de la Myéline, Neuroprotection et Stratégies Thérapeutiques, INSERM U1119/Université de Strasbourg, Faculté de Médecine, 11 rue Humann, 67085, Strasbourg, France.,Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France.,Department of Neurology, University Hospital of Strasbourg, Strasbourg, France
| | - Omar Taleb
- Biopathologie de la Myéline, Neuroprotection et Stratégies Thérapeutiques, INSERM U1119/Université de Strasbourg, Faculté de Médecine, 11 rue Humann, 67085, Strasbourg, France.,Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France
| | - Nelly Boehm
- Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France.,Faculty of Medicine, Institute of Histology, University of Strasbourg, Strasbourg, France
| | - Ayikoe Guy Mensah-Nyagan
- Biopathologie de la Myéline, Neuroprotection et Stratégies Thérapeutiques, INSERM U1119/Université de Strasbourg, Faculté de Médecine, 11 rue Humann, 67085, Strasbourg, France.,Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France
| | - Elisabeth Trifilieff
- Biopathologie de la Myéline, Neuroprotection et Stratégies Thérapeutiques, INSERM U1119/Université de Strasbourg, Faculté de Médecine, 11 rue Humann, 67085, Strasbourg, France.,Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France
| | - Jérôme de Seze
- Biopathologie de la Myéline, Neuroprotection et Stratégies Thérapeutiques, INSERM U1119/Université de Strasbourg, Faculté de Médecine, 11 rue Humann, 67085, Strasbourg, France.,Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France.,Department of Neurology, University Hospital of Strasbourg, Strasbourg, France
| | - Susana Brun
- Biopathologie de la Myéline, Neuroprotection et Stratégies Thérapeutiques, INSERM U1119/Université de Strasbourg, Faculté de Médecine, 11 rue Humann, 67085, Strasbourg, France. .,Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France.
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8
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Bhat AH, Maity S, Giri K, Ambatipudi K. Protein glycosylation: Sweet or bitter for bacterial pathogens? Crit Rev Microbiol 2019; 45:82-102. [PMID: 30632429 DOI: 10.1080/1040841x.2018.1547681] [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] [Indexed: 01/14/2023]
Abstract
Protein glycosylation systems in many bacteria are often associated with crucial biological processes like pathogenicity, immune evasion and host-pathogen interactions, implying the significance of protein-glycan linkage. Similarly, host protein glycosylation has been implicated in antimicrobial activity as well as in promoting growth of beneficial strains. In fact, few pathogens notably modulate host glycosylation machineries to facilitate their survival. To date, diverse chemical and biological strategies have been developed for conjugate vaccine production for disease control. Bioconjugate vaccines, largely being produced by glycoengineering using PglB (the N-oligosaccharyltransferase from Campylobacter jejuni) in suitable bacterial hosts, have been highly promising with respect to their effectiveness in providing protective immunity and ease of production. Recently, a novel method of glycoconjugate vaccine production involving an O-oligosaccharyltransferase, PglL from Neisseria meningitidis, has been optimized. Nevertheless, many questions on defining antigenic determinants, glycosylation markers, species-specific differences in glycosylation machineries, etc. still remain unanswered, necessitating further exploration of the glycosylation systems of important pathogens. Hence, in this review, we will discuss the impact of bacterial protein glycosylation on its pathogenesis and the interaction of pathogens with host protein glycosylation, followed by a discussion on strategies used for bioconjugate vaccine development.
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Affiliation(s)
- Aadil Hussain Bhat
- a Department of Biotechnology , Indian Institute of Technology Roorkee , Roorkee , Uttarakhand 247667 , India
| | - Sudipa Maity
- a Department of Biotechnology , Indian Institute of Technology Roorkee , Roorkee , Uttarakhand 247667 , India
| | - Kuldeep Giri
- a Department of Biotechnology , Indian Institute of Technology Roorkee , Roorkee , Uttarakhand 247667 , India
| | - Kiran Ambatipudi
- a Department of Biotechnology , Indian Institute of Technology Roorkee , Roorkee , Uttarakhand 247667 , India
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9
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Yu C, Chen H, Tian F, Yang F, Yuan X, Yang C, He C. A ten gene-containing genomic island determines flagellin glycosylation: implication for its regulatory role in motility and virulence of Xanthomonas oryzae pv. oryzae. MOLECULAR PLANT PATHOLOGY 2018; 19:579-592. [PMID: 28213905 PMCID: PMC6638077 DOI: 10.1111/mpp.12543] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 02/06/2017] [Accepted: 02/13/2017] [Indexed: 05/19/2023]
Abstract
Flagellin glycosylation plays a crucial role in flagellar assembly, motility and virulence in several pathogenic bacteria. However, little is known about the genetic determinants and biological functions of flagellin glycosylation in Xanthomonas oryzae pv. oryzae (Xoo), the causal pathogen of bacterial blight of rice. Here, the structure, regulation and functions of a ten-gene cluster gigX (glycosylation island genes of Xoo), which was embedded in a flagellar regulon, were characterized. gigX1 to gigX10 encoded putative enzymes or proteins involved in glycan biosynthesis and transfer, including a nucleotide sugar transaminase, an acyl-carrier protein (ACP), a 3-oxoacyl-ACP synthase, a 3-oxoacyl-ACP reductase, a dehydrogenase, an acetyltransferase, a ring hydroxylating dioxygenase, a hypothetical protein, a methyltransferanse and a glycosyltransferase, respectively. The gigX genes were co-transcribed in an operon and up-regulated by the upstream σ54 factor RpoN2 and transcriptional activator FleQ. In-frame deletion of each gigX gene affected flagellin glycosylation modification, meaning that the unglycosylated flagellin of the mutants was smaller than the glycosylated flagellin of the wild-type. No significant changes in flagellar filament and motility were observed in the ΔgigX mutants, among which only ΔgigX6 displayed increased swimming ability. Importantly, all mutants, except ΔgigX9, showed significantly increased virulence and bacterial growth in the susceptible rice cultivar IR24, and ΔgigX1 and ΔgigX10 showed enhanced type III secretion system (T3SS)-related gene expression. Moreover, the glycosylated flagellin of the wild-type induced higher H2 O2 levels in rice leaves than did the unglycosylated flagellins of ΔgigX1 or ΔgigX10. Taken together, this study reveals that the gigX cluster determines flagellin glycosylation, and implicates the regulatory role of post-translational modification with the glycosylation, acetylation and methylation of flagellin in the regulation of motility and virulence of Xoo.
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Affiliation(s)
- Chao Yu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing100193China
| | - Huamin Chen
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing100193China
| | - Fang Tian
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing100193China
| | - Fenghuan Yang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing100193China
| | - Xiaochen Yuan
- Department of Biological SciencesUniversity of Wisconsin‐MilwaukeeMilwaukeeWI53211USA
| | - Ching‐Hong Yang
- Department of Biological SciencesUniversity of Wisconsin‐MilwaukeeMilwaukeeWI53211USA
| | - Chenyang He
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing100193China
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10
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Fulton KM, Li J, Tomas JM, Smith JC, Twine SM. Characterizing bacterial glycoproteins with LC-MS. Expert Rev Proteomics 2018; 15:203-216. [PMID: 29400572 DOI: 10.1080/14789450.2018.1435276] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
INTRODUCTION Though eukaryotic glycoproteins have been studied since their discovery in the 1930s, the first bacterial glycoprotein was not identified until the 1970s. As a result, their role in bacterial pathogenesis is still not well understood and they remain an understudied component of bacterial virulence. In recent years, mass spectrometry has emerged as a leading technology for the study of bacterial glycoproteins, largely due to its sensitivity and versatility. Areas covered: Identification and comprehensive characterization of bacterial glycoproteins usually requires multiple complementary mass spectrometry approaches, including intact protein analysis, top-down analysis, and bottom-up methods used in combination with specialized liquid chromatography. This review provides an overview of liquid chromatography separation technologies, as well as current and emerging mass spectrometry approaches used specifically for bacterial glycoprotein identification and characterization. Expert commentary: Bacterial glycoproteins may have significant clinical utility as a result of their unique structures and exposure on the surface of the cells. Better understanding of these glycoconjugates is an essential first step towards that goal. These often unique structures, and by extension the key enzymes involved in their synthesis, represent promising targets for novel antimicrobials, while unique carbohydrate structures may be used as antigens in vaccines or as biomarkers.
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Affiliation(s)
- Kelly M Fulton
- a Human Health Therapeutics Portfolio , National Research Council Canada , Ottawa , Canada
| | - Jianjun Li
- a Human Health Therapeutics Portfolio , National Research Council Canada , Ottawa , Canada
| | - Juan M Tomas
- b Departament de Microbiologia, Facultat de Biologia , Universitat de Barcelona , Barcelona , Spain
| | - Jeffrey C Smith
- c Department of Chemistry , Carleton University , Ottawa , Canada
| | - Susan M Twine
- a Human Health Therapeutics Portfolio , National Research Council Canada , Ottawa , Canada
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11
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Gu H. Role of Flagella in the Pathogenesis of Helicobacter pylori. Curr Microbiol 2017; 74:863-869. [PMID: 28444418 PMCID: PMC5447363 DOI: 10.1007/s00284-017-1256-4] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 04/18/2017] [Indexed: 12/15/2022]
Abstract
This review aimed to investigate the role of Helicobacter pylori flagella on the pathogenicity of this bacterium in humans. Helicobacter pylori is a flagellated pathogen that colonizes the human gastroduodenal mucosa and produces inflammation, and is responsible for gastrointestinal disease. Its pathogenesis is attributed to colonization and virulence factors. The primary function of H. pylori flagella is to provide motility. We believe that H. pylori flagella play an important role in the colonization of the gastrointestinal mucosa. Therefore, we reviewed previous studies on flagellar morphology and motility in order to explore the relationship between H. pylori flagella and pathogenicity. Further investigation is required to confirm the association between flagella and pathogenicity in H. pylori.
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Affiliation(s)
- Haiying Gu
- Medical School, Ningbo University, Ningbo, 315211, China.
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12
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Bouché L, Panico M, Hitchen P, Binet D, Sastre F, Faulds-Pain A, Valiente E, Vinogradov E, Aubry A, Fulton K, Twine S, Logan SM, Wren BW, Dell A, Morris HR. The Type B Flagellin of Hypervirulent Clostridium difficile Is Modified with Novel Sulfonated Peptidylamido-glycans. J Biol Chem 2016; 291:25439-25449. [PMID: 27758867 PMCID: PMC5207245 DOI: 10.1074/jbc.m116.749481] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 09/12/2016] [Indexed: 01/15/2023] Open
Abstract
Glycosylation of flagellins is a well recognized property of many bacterial species. In this study, we describe the structural characterization of novel flagellar glycans from a number of hypervirulent strains of C. difficile. We used mass spectrometry (nano-LC-MS and MS/MS analysis) to identify a number of putative glycopeptides that carried a variety of glycoform substitutions, each of which was linked through an initial N-acetylhexosamine residue to Ser or Thr. Detailed analysis of a LLDGSSTEIR glycopeptide released by tryptic digestion, which carried two variant structures, revealed that the glycopeptide contained, in addition to carbohydrate moieties, a novel structural entity. A variety of electrospray-MS strategies using Q-TOF technology were used to define this entity, including positive and negative ion collisionally activated decomposition MS/MS, which produced unique fragmentation patterns, and high resolution accurate mass measurement to allow derivation of atomic compositions, leading to the suggestion of a taurine-containing peptidylamido-glycan structure. Finally, NMR analysis of flagellin glycopeptides provided complementary information. The glycan portion of the modification was assigned as α-Fuc3N-(1→3)-α-Rha-(1→2)-α-Rha3OMe-(1→3)-β-GlcNAc-(1→)Ser, and the novel capping moiety was shown to be comprised of taurine, alanine, and glycine. This is the first report of a novel O-linked sulfonated peptidylamido-glycan moiety decorating a flagellin protein.
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Affiliation(s)
- Laura Bouché
- From the Department of Life Sciences, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Maria Panico
- From the Department of Life Sciences, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Paul Hitchen
- From the Department of Life Sciences, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Daniel Binet
- BioPharmaSpec, Suite 3.1 Lido Medical Centre, St. Saviours Road, Jersey JE2 7LA, United Kingdom
| | - Federico Sastre
- From the Department of Life Sciences, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Alexandra Faulds-Pain
- the Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Esmeralda Valiente
- the Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Evgeny Vinogradov
- the Vaccine Program, Human Health Therapeutics Portfolio, National Research Council, Ottawa, Ontario K1A 0R6, Canada, and
| | - Annie Aubry
- the Vaccine Program, Human Health Therapeutics Portfolio, National Research Council, Ottawa, Ontario K1A 0R6, Canada, and
| | - Kelly Fulton
- the Vaccine Program, Human Health Therapeutics Portfolio, National Research Council, Ottawa, Ontario K1A 0R6, Canada, and
| | - Susan Twine
- the Vaccine Program, Human Health Therapeutics Portfolio, National Research Council, Ottawa, Ontario K1A 0R6, Canada, and
| | - Susan M Logan
- the Vaccine Program, Human Health Therapeutics Portfolio, National Research Council, Ottawa, Ontario K1A 0R6, Canada, and
| | - Brendan W Wren
- the Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Anne Dell
- From the Department of Life Sciences, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom,
| | - Howard R Morris
- From the Department of Life Sciences, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom.,BioPharmaSpec, Suite 3.1 Lido Medical Centre, St. Saviours Road, Jersey JE2 7LA, United Kingdom
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13
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Abstract
There is an ongoing race between bacterial evolution and medical advances. Pathogens have the advantages of short generation times and horizontal gene transfer that enable rapid adaptation to new host environments and therapeutics that currently outpaces clinical research. Antibiotic resistance, the growing impact of nosocomial infections, cancer-causing bacteria, the risk of zoonosis, and the possibility of biowarfare all emphasize the increasingly urgent need for medical research focussed on bacterial pathogens. Bacterial glycoproteins are promising targets for alternative therapeutic intervention since they are often surface exposed, involved in host-pathogen interactions, required for virulence, and contain distinctive glycan structures. The potential exists to exploit these unique structures to improve clinical prevention, diagnosis, and treatment strategies. Translation of the potential in this field to actual clinical impact is an exciting prospect for fighting infectious diseases.
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Affiliation(s)
- Kelly M Fulton
- a Human Health Therapeutics Portfolio , National Research Council Canada , Ottawa , Canada
| | - Jeffrey C Smith
- b Department of Chemistry and Institute of Biochemistry , Carleton University , Ottawa , Canada
| | - Susan M Twine
- a Human Health Therapeutics Portfolio , National Research Council Canada , Ottawa , Canada
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14
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King JE, Roberts IS. Bacterial Surfaces: Front Lines in Host-Pathogen Interaction. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 915:129-56. [PMID: 27193542 DOI: 10.1007/978-3-319-32189-9_10] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
All bacteria are bound by at least one membrane that acts as a barrier between the cell's interior and the outside environment. Surface components within and attached to the cell membrane are essential for ensuring that the overall homeostasis of the cell is maintained. However, many surface components of the bacterial cell also have an indispensable role mediating interactions of the bacteria with their immediate environment and as such are essential to the pathogenesis of infectious disease. During the course of an infection, bacterial pathogens will encounter many different ecological niches where environmental conditions such as salinity, temperature, pH, and the availability of nutrients fluctuate. It is the bacterial cell surface that is at the front-line of these host-pathogen interactions often protecting the bacterium from hostile surroundings but at the same time playing a critical role in the adherence to host tissues promoting colonization and subsequent infection. To deal effectively with the changing environments that pathogens may encounter in different ecological niches within the host many of the surface components of the bacterial cell are subject to phenotypic variation resulting in heterogeneous subpopulations of bacteria within the clonal population. This dynamic phenotypic heterogeneity ensures that at least a small fraction of the population will be adapted for a particular circumstance should it arise. Diversity within the clonal population has often been masked by studies on entire bacterial populations where it was often assumed genes were expressed in a uniform manner. This chapter, therefore, aims to highlight the non-uniformity in certain cell surface structures and will discuss the implication of this heterogeneity in bacterial-host interaction. Some of the recent advances in studying bacterial surface structures at the single cell level will also be reviewed.
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Affiliation(s)
- Jane E King
- Faculty of Life Sciences, University of Manchester, Manchester, M13 9PT, UK
| | - Ian S Roberts
- Faculty of Life Sciences, University of Manchester, Manchester, M13 9PT, UK.
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15
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Martinez LE, Hardcastle JM, Wang J, Pincus Z, Tsang J, Hoover TR, Bansil R, Salama NR. Helicobacter pylori strains vary cell shape and flagellum number to maintain robust motility in viscous environments. Mol Microbiol 2016; 99:88-110. [PMID: 26365708 PMCID: PMC4857613 DOI: 10.1111/mmi.13218] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/09/2015] [Indexed: 12/24/2022]
Abstract
The helical shape of the human stomach pathogen Helicobacter pylori has been suggested to provide mechanical advantage for penetrating the viscous stomach mucus layer. Using single-cell tracking and quantitative morphology analysis, we document marked variation in cell body helical parameters and flagellum number among H. pylori strains leading to distinct and broad speed distributions in broth and viscous gastric mucin media. These distributions reflect both temporal variation in swimming speed and morphologic variation within the population. Isogenic mutants with straight-rod morphology showed 7-21% reduction in speed and a lower fraction of motile bacteria. Mutational perturbation of flagellum number revealed a 19% increase in speed with 4 versus 3 median flagellum number. Resistive force theory modeling incorporating variation of both cell shape and flagellum number predicts qualitative speed differences of 10-30% among strains. However, quantitative comparisons suggest resistive force theory underestimates the influence of cell body shape on speed for helical shaped bacteria.
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Affiliation(s)
- Laura E. Martinez
- Graduate Program in Pathobiology, Department of Global Health, University of Washington, Seattle, WA 98195 USA
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA 98109 USA
| | | | - Jeffrey Wang
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA 98109 USA
| | - Zachary Pincus
- Department of Developmental Biology and Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Jennifer Tsang
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
| | - Timothy R. Hoover
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
| | - Rama Bansil
- Department of Physics, Boston University, Boston, MA 02215 USA
| | - Nina R. Salama
- Graduate Program in Pathobiology, Department of Global Health, University of Washington, Seattle, WA 98195 USA
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA 98109 USA
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16
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Ardissone S, Viollier PH. Interplay between flagellation and cell cycle control in Caulobacter. Curr Opin Microbiol 2015; 28:83-92. [PMID: 26476805 DOI: 10.1016/j.mib.2015.08.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2015] [Revised: 08/09/2015] [Accepted: 08/11/2015] [Indexed: 12/21/2022]
Abstract
The assembly of the flagellum, a sophisticated nanomachine powering bacterial locomotion in liquids and across surfaces, is highly regulated. In the synchronizable α-Proteobacterium Caulobacter crescentus, the flagellum is built at a pre-selected cell pole and flagellar transcript abundance oscillates during the cell cycle. Conserved regulators not only dictate when the transcripts encoding flagellar structural proteins peak, but also those encoding polarization factors. Additionally, post-transcriptional cell cycle cues facilitate flagellar (dis-)assembly at the new cell pole. Because of this regulatory complexity and the power of bacterial genetics, motility is a suitable and simple proxy for dissecting how bacteria implement cell cycle progression and polarity, while also providing clues on how bacteria might decide when and where to display other surface structures.
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Affiliation(s)
- Silvia Ardissone
- Department of Microbiology and Molecular Medicine, Institute of Genetics and Genomics in Geneva (iGE3), Faculty of Medicine, University of Geneva, Rue Michel Servet 1, 1211 Geneva 4, Switzerland
| | - Patrick H Viollier
- Department of Microbiology and Molecular Medicine, Institute of Genetics and Genomics in Geneva (iGE3), Faculty of Medicine, University of Geneva, Rue Michel Servet 1, 1211 Geneva 4, Switzerland.
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17
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da Costa DM, Pereira EDS, Rabenhorst SHB. What exists beyond cagA and vacA? Helicobacter pylori genes in gastric diseases. World J Gastroenterol 2015; 21:10563-72. [PMID: 26457016 PMCID: PMC4588078 DOI: 10.3748/wjg.v21.i37.10563] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 06/13/2015] [Accepted: 08/25/2015] [Indexed: 02/06/2023] Open
Abstract
Helicobacter pylori (H. pylori) infection is present in more than half the world's population and has been associated with several gastric disorders, such as gastritis, peptic ulceration, and gastric adenocarcinoma. The clinical outcome of this infection depends on host and bacterial factors where H. pylori virulence genes seem to play a relevant role. Studies of cagA and vacA genes established that they were determining factors in gastric pathogenesis. However, there are gastric cancer cases that are cagA-negative. Several other virulence genes have been searched for, but these genes remain less well known that cagA and vacA. Thus, this review aimed to establish which genes have been suggested as potentially relevant virulence factors for H. pylori-associated gastrointestinal diseases. We focused on the cag-pathogenicity island, genes with adherence and motility functions, and iceA based on the relevance shown in several studies in the literature.
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18
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Kim HS, Im HN, An DR, Yoon JY, Jang JY, Mobashery S, Hesek D, Lee M, Yoo J, Cui M, Choi S, Kim C, Lee NK, Kim SJ, Kim JY, Bang G, Han BW, Lee BI, Yoon HJ, Suh SW. The Cell Shape-determining Csd6 Protein from Helicobacter pylori Constitutes a New Family of L,D-Carboxypeptidase. J Biol Chem 2015; 290:25103-17. [PMID: 26306031 PMCID: PMC4599014 DOI: 10.1074/jbc.m115.658781] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Indexed: 01/01/2023] Open
Abstract
Helicobacter pylori causes gastrointestinal diseases, including gastric cancer. Its high motility in the viscous gastric mucosa facilitates colonization of the human stomach and depends on the helical cell shape and the flagella. In H. pylori, Csd6 is one of the cell shape-determining proteins that play key roles in alteration of cross-linking or by trimming of peptidoglycan muropeptides. Csd6 is also involved in deglycosylation of the flagellar protein FlaA. To better understand its function, biochemical, biophysical, and structural characterizations were carried out. We show that Csd6 has a three-domain architecture and exists as a dimer in solution. The N-terminal domain plays a key role in dimerization. The middle catalytic domain resembles those of l,d-transpeptidases, but its pocket-shaped active site is uniquely defined by the four loops I to IV, among which loops I and III show the most distinct variations from the known l,d-transpeptidases. Mass analyses confirm that Csd6 functions only as an l,d-carboxypeptidase and not as an l,d-transpeptidase. The d-Ala-complexed structure suggests possible binding modes of both the substrate and product to the catalytic domain. The C-terminal nuclear transport factor 2-like domain possesses a deep pocket for possible binding of pseudaminic acid, and in silico docking supports its role in deglycosylation of flagellin. On the basis of these findings, it is proposed that H. pylori Csd6 and its homologs constitute a new family of l,d-carboxypeptidase. This work provides insights into the function of Csd6 in regulating the helical cell shape and motility of H. pylori.
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Affiliation(s)
- Hyoun Sook Kim
- From the Departments of Chemistry and Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul 151-742, Republic of Korea
| | - Ha Na Im
- Biophysics and Chemical Biology, College of Natural Sciences, and
| | - Doo Ri An
- Biophysics and Chemical Biology, College of Natural Sciences, and
| | - Ji Young Yoon
- Biophysics and Chemical Biology, College of Natural Sciences, and
| | | | - Shahriar Mobashery
- the Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
| | - Dusan Hesek
- the Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
| | - Mijoon Lee
- the Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
| | - Jakyung Yoo
- the National Leading Research Laboratory of Molecular Modeling and Drug Design, College of Pharmacy, Graduate School of Pharmaceutical Sciences, and Global Top 5 Research Program, Ewha Womans University, Seoul 120-750, Republic of Korea
| | - Minghua Cui
- the National Leading Research Laboratory of Molecular Modeling and Drug Design, College of Pharmacy, Graduate School of Pharmaceutical Sciences, and Global Top 5 Research Program, Ewha Womans University, Seoul 120-750, Republic of Korea
| | - Sun Choi
- the National Leading Research Laboratory of Molecular Modeling and Drug Design, College of Pharmacy, Graduate School of Pharmaceutical Sciences, and Global Top 5 Research Program, Ewha Womans University, Seoul 120-750, Republic of Korea
| | - Cheolhee Kim
- the Department of Physics, POSTECH, Pohang 790-784, Republic of Korea
| | - Nam Ki Lee
- the Department of Physics, POSTECH, Pohang 790-784, Republic of Korea
| | - Soon-Jong Kim
- the Department of Chemistry, Mokpo National University, Chonnam 534-729, Republic of Korea
| | - Jin Young Kim
- the Division of Mass Spectrometry, Korea Basic Science Institute, Chungbuk 363-883, Republic of Korea, and
| | - Geul Bang
- the Division of Mass Spectrometry, Korea Basic Science Institute, Chungbuk 363-883, Republic of Korea, and
| | - Byung Woo Han
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul 151-742, Republic of Korea
| | - Byung Il Lee
- the Biomolecular Function Research Branch, Division of Convergence Technology, Research Institute, National Cancer Center, Gyeonggi 410-769, Republic of Korea
| | | | - Se Won Suh
- From the Departments of Chemistry and Biophysics and Chemical Biology, College of Natural Sciences, and
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19
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Tan FY, Tang CM, Exley RM. Sugar coating: bacterial protein glycosylation and host–microbe interactions. Trends Biochem Sci 2015; 40:342-50. [DOI: 10.1016/j.tibs.2015.03.016] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 03/11/2015] [Accepted: 03/31/2015] [Indexed: 01/29/2023]
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20
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Li H, Yu C, Chen H, Tian F, He C. PXO_00987, a putative acetyltransferase, is required for flagellin glycosylation, and regulates flagellar motility, exopolysaccharide production, and biofilm formation in Xanthomonas oryzae pv. oryzae. Microb Pathog 2015; 85:50-7. [PMID: 26065383 DOI: 10.1016/j.micpath.2015.06.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 05/27/2015] [Accepted: 06/05/2015] [Indexed: 10/23/2022]
Abstract
Acetyltransferases catalyze an important process for sugar or protein modification. In the genome of Xanthomonas oryzae pv. oryzae (Xoo), the causal agent of bacterial blight of rice, there are 32 acetyltransferase-encoding genes belonging to different families. In this work, we focused on PXO_00987, which encodes a putative acetyltransferase in the flagellar regulon. We found that mutation of PXO_00987 gene abolished the glycosylation of wild-type flagellin protein of Xoo. In addition, the PXO_00987 mutant showed enhanced swimming motility, and decreased exopolysaccharide production and biofilm formation. Virulence assays demonstrated that the PXO_00987 mutant caused shorter disease length on rice leaves, suggesting that the function of PXO_00987 contributes to the pathogenesis of Xoo.
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Affiliation(s)
- Haiyun Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Chao Yu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Huamin Chen
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Fang Tian
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
| | - Chenyang He
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
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21
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The sweet tooth of bacteria: common themes in bacterial glycoconjugates. Microbiol Mol Biol Rev 2015; 78:372-417. [PMID: 25184559 DOI: 10.1128/mmbr.00007-14] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Humans have been increasingly recognized as being superorganisms, living in close contact with a microbiota on all their mucosal surfaces. However, most studies on the human microbiota have focused on gaining comprehensive insights into the composition of the microbiota under different health conditions (e.g., enterotypes), while there is also a need for detailed knowledge of the different molecules that mediate interactions with the host. Glycoconjugates are an interesting class of molecules for detailed studies, as they form a strain-specific barcode on the surface of bacteria, mediating specific interactions with the host. Strikingly, most glycoconjugates are synthesized by similar biosynthesis mechanisms. Bacteria can produce their major glycoconjugates by using a sequential or an en bloc mechanism, with both mechanistic options coexisting in many species for different macromolecules. In this review, these common themes are conceptualized and illustrated for all major classes of known bacterial glycoconjugates, with a special focus on the rather recently emergent field of glycosylated proteins. We describe the biosynthesis and importance of glycoconjugates in both pathogenic and beneficial bacteria and in both Gram-positive and -negative organisms. The focus lies on microorganisms important for human physiology. In addition, the potential for a better knowledge of bacterial glycoconjugates in the emerging field of glycoengineering and other perspectives is discussed.
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22
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Ding Y, Uchida K, Aizawa SI, Murphy K, Berezuk A, Khursigara CM, Chong JPJ, Jarrell KF. Effects of N-glycosylation site removal in archaellins on the assembly and function of archaella in Methanococcus maripaludis. PLoS One 2015; 10:e0116402. [PMID: 25700084 PMCID: PMC4336324 DOI: 10.1371/journal.pone.0116402] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 12/09/2014] [Indexed: 12/22/2022] Open
Abstract
In Methanococcus maripaludis S2, the swimming organelle, the archaellum, is composed of three archaellins, FlaB1S2, FlaB2S2 and FlaB3S2. All three are modified with an N-linked tetrasaccharide at multiple sites. Disruption of the N-linked glycosylation pathway is known to cause defects in archaella assembly or function. Here, we explored the potential requirement of N-glycosylation of archaellins on archaellation by investigating the effects of eliminating the 4 N-glycosylation sites in the wildtype FlaB2S2 protein in all possible combinations either by Asn to Glu (N to Q) substitution or Asn to Asp (N to D) substitutions of the N-glycosylation sequon asparagine. The ability of these mutant derivatives to complement a non-archaellated ΔflaB2S2 strain was examined by electron microscopy (for archaella assembly) and swarm plates (for analysis of swimming). Western blot results showed that all mutated FlaB2S2 proteins were expressed and of smaller apparent molecular mass compared to wildtype FlaB2S2, consistent with the loss of glycosylation sites. In the 8 single-site mutant complements, archaella were observed on the surface of Q2, D2 and D4 (numbers after N or Q refer to the 1st to 4th glycosylation site). Of the 6 double-site mutation complementations all were archaellated except D1,3. Of the 4 triple-site mutation complements, only D2,3,4 was archaellated. Elimination of all 4 N-glycosylation sites resulted in non-archaellated cells, indicating some minimum amount of archaellin glycosylation was necessary for their incorporation into stable archaella. All complementations that led to a return of archaella also resulted in motile cells with the exception of the D4 version. In addition, a series of FlaB2S2 scanning deletions each missing 10 amino acids was also generated and tested for their ability to complement the ΔflaB2S2 strain. While most variants were expressed, none of them restored archaellation, although FlaB2S2 harbouring a smaller 3-amino acid deletion was able to partially restore archaellation.
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Affiliation(s)
- Yan Ding
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, Ontario, Canada
| | - Kaoru Uchida
- Department of Life Sciences, Prefectural University of Hiroshima, 562 Nanatsuka, Shobara, Hiroshima, Japan
| | - Shin-Ichi Aizawa
- Department of Life Sciences, Prefectural University of Hiroshima, 562 Nanatsuka, Shobara, Hiroshima, Japan
| | - Kathleen Murphy
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - Alison Berezuk
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - Cezar M. Khursigara
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - James P. J. Chong
- Department of Biology, University of York, Heslington, York, United Kingdom
| | - Ken F. Jarrell
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, Ontario, Canada
- * E-mail:
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23
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Lowry RC, Parker JL, Kumbhar R, Mesnage S, Shaw JG, Stafford GP. The Aeromonas caviae AHA0618 gene modulates cell length and influences swimming and swarming motility. Microbiologyopen 2014; 4:220-234. [PMID: 25515520 PMCID: PMC4398505 DOI: 10.1002/mbo3.233] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 11/17/2014] [Accepted: 11/24/2014] [Indexed: 01/12/2023] Open
Abstract
Aeromonas caviae is motile via a polar flagellum in liquid culture, with a lateral flagella system used for swarming on solid surfaces. The polar flagellum also has a role in cellular adherence and biofilm formation. The two subunits of the polar flagellum, FlaA and FlaB, are posttranslationally modified by O-linked glycosylation with pseudaminic acid on 6–8 serine and threonine residues within the central region of these proteins. This modification is essential for the formation of the flagellum. Aeromonas caviae possesses the simplest set of genes required for bacterial glycosylation currently known, with the putative glycosyltransferase, Maf1, being described recently. Here, we investigated the role of the AHA0618 gene, which shares homology (37% at the amino acid level) with the central region of a putative deglycosylation enzyme (HP0518) from the human pathogen Helicobacter pylori, which also glycosylates its flagellin and is proposed to be part of a flagellin deglycosylation pathway. Phenotypic analysis of an AHA0618 A. caviae mutant revealed increased swimming and swarming motility compared to the wild-type strain but without any detectable effects on the glycosylation status of the polar flagellins when analyzed by western blot analysis or mass spectroscopy. Bioinformatic analysis of the protein AHA0618, demonstrated homology to a family of l,d-transpeptidases involved in cell wall biology and peptidoglycan cross-linking (YkuD-like). Scanning electron microscopy (SEM) and fluorescence microscopy analysis of the wild-type and AHA0618-mutant A. caviae strains revealed the mutant to be subtly but significantly shorter than wild-type cells; a phenomenon that could be recovered when either AHA0618 or H. pylori HP0518 were introduced. We can therefore conclude that AHA0618 does not affect A. caviae behavior by altering polar flagellin glycosylation levels but is likely to have a role in peptidoglycan processing at the bacterial cell wall, consequently altering cell length and hence influencing motility.
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Affiliation(s)
- Rebecca C Lowry
- Department of Infection and Immunity, University of Sheffield Medical School, Beech Hill Road, Sheffield, S10 2RX, UK
| | - Jennifer L Parker
- Department of Infection and Immunity, University of Sheffield Medical School, Beech Hill Road, Sheffield, S10 2RX, UK
| | - Ramhari Kumbhar
- Department of Infection and Immunity, University of Sheffield Medical School, Beech Hill Road, Sheffield, S10 2RX, UK
| | - Stephane Mesnage
- Department of Molecular Biology and Biotechnology, Firth Court, Western Bank, Sheffield, S10 2TN, UK
| | - Jonathan G Shaw
- Department of Infection and Immunity, University of Sheffield Medical School, Beech Hill Road, Sheffield, S10 2RX, UK
| | - Graham P Stafford
- School of Clinical Dentistry, Claremont Crescent, University of Sheffield, Sheffield, S10 2TA, UK
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24
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Merino S, Wilhelms M, Tomás JM. Role of Aeromonas hydrophila flagella glycosylation in adhesion to Hep-2 cells, biofilm formation and immune stimulation. Int J Mol Sci 2014; 15:21935-46. [PMID: 25464381 PMCID: PMC4284686 DOI: 10.3390/ijms151221935] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Revised: 11/13/2014] [Accepted: 11/21/2014] [Indexed: 12/30/2022] Open
Abstract
Abstract: Polar flagellin proteins from Aeromonas hydrophila strain AH-3 (serotype O34) were found to be O-glycosylated with a heterogeneous heptasaccharide glycan. Two mutants with altered (light and strong) polar flagella glycosylation still able to produce flagella were previously obtained, as well as mutants lacking the O34-antigen lipopolysaccharide (LPS) but with unaltered polar flagella glycosylation. We compared these mutants, altogether with the wild type strain, in different studies to conclude that polar flagella glycosylation is extremely important for A. hydrophila adhesion to Hep-2 cells and biofilm formation. Furthermore, the polar flagella glycosylation is an important factor for the immune stimulation of IL-8 production via toll receptor 5 (TLR5).
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Affiliation(s)
- Susana Merino
- Departamento de Microbiología, Facultad de Biología, Universidad de Barcelona, Diagonal 643, 08071 Barcelona, Spain.
| | - Markus Wilhelms
- Departamento de Microbiología, Facultad de Biología, Universidad de Barcelona, Diagonal 643, 08071 Barcelona, Spain.
| | - Juan M Tomás
- Departamento de Microbiología, Facultad de Biología, Universidad de Barcelona, Diagonal 643, 08071 Barcelona, Spain.
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N-Glycosylation of the archaellum filament is not important for archaella assembly and motility, although N-Glycosylation is essential for motility in Sulfolobus acidocaldarius. Biochimie 2014; 118:294-301. [PMID: 25447136 DOI: 10.1016/j.biochi.2014.10.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 10/17/2014] [Indexed: 12/29/2022]
Abstract
N-Glycosylation is one of the predominant posttranslational modifications, which is found in all three domains of life. N-Glycosylation has been shown to influence many biological aspects of proteins, like protein folding, stability or activity. In this study we demonstrate that the archaellum filament subunit FlaB of Sulfolobus acidocaldarius is N-glycosylated. Each of the six predicted N-Glycosylation sites within FlaB are modified with the attachment of an N-glycan. Although, it has been previously shown that N-Glycosylation is essential for motility in S. acidocaldarius, as defects in the N-Glycosylation process resulted in none or reduced motile cells, strains lacking one to all six N-Glycosylation sites within FlaB still remained motile. Deletion of the first five N-Glycosylation sites in FlaB did not significantly affect the motility, whereas removal of all six N-Glycosylation sites reduced motility by about 40%. Transmission electron microscopy analyses of non glycosylated and glycosylated archaellum filament revealed no structural change in length. Therefore N-Glycosylation does not appear to be important for the stability and assembly of the archaellum filament itself, but plays a role in other parts of the archaellum assembly.
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Campylobacter jejuni motility is required for infection of the flagellotropic bacteriophage F341. Appl Environ Microbiol 2014; 80:7096-106. [PMID: 25261508 DOI: 10.1128/aem.02057-14] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Previous studies have identified a specific modification of the capsular polysaccharide as receptor for phages that infect Campylobacter jejuni. Using acapsular kpsM mutants of C. jejuni strains NCTC11168 and NCTC12658, we found that bacteriophage F341 infects C. jejuni independently of the capsule. In contrast, phage F341 does not infect C. jejuni NCTC11168 mutants that either lack the flagellar filaments (ΔflaAB) or that have paralyzed, i.e., nonrotating, flagella (ΔmotA and ΔflgP). Complementing flgP confirmed that phage F341 requires rotating flagella for successful infection. Furthermore, adsorption assays demonstrated that phage F341 does not adsorb to these nonmotile C. jejuni NCTC11168 mutants. Taken together, we propose that phage F341 uses the flagellum as a receptor. Phage-host interactions were investigated using fluorescence confocal and transmission electron microscopy. These data demonstrate that F341 binds to the flagellum by perpendicular attachment with visible phage tail fibers interacting directly with the flagellum. Our data are consistent with the movement of the C. jejuni flagellum being required for F341 to travel along the filament to reach the basal body of the bacterium. The initial binding to the flagellum may cause a conformational change of the phage tail that enables DNA injection after binding to a secondary receptor.
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27
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Faulds-Pain A, Twine SM, Vinogradov E, Strong PCR, Dell A, Buckley AM, Douce GR, Valiente E, Logan SM, Wren BW. The post-translational modification of the Clostridium difficile flagellin affects motility, cell surface properties and virulence. Mol Microbiol 2014; 94:272-89. [PMID: 25135277 PMCID: PMC4441256 DOI: 10.1111/mmi.12755] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/13/2014] [Indexed: 01/05/2023]
Abstract
Clostridium difficile is a prominent nosocomial pathogen, proliferating and causing enteric disease in individuals with a compromised gut microflora. We characterized the post-translational modification of flagellin in C. difficile 630. The structure of the modification was solved by nuclear magnetic resonance and shown to contain an N-acetylglucosamine substituted with a phosphorylated N-methyl-l-threonine. A reverse genetics approach investigated the function of the putative four-gene modification locus. All mutants were found to have truncated glycan structures by LC-MS/MS, taking into account bioinformatic analysis, we propose that the open reading frame CD0241 encodes a kinase involved in the transfer of the phosphate to the threonine, the CD0242 protein catalyses the addition of the phosphothreonine to the N-acetylglucosamine moiety and CD0243 transfers the methyl group to the threonine. Some mutations affected motility and caused cells to aggregate to each other and abiotic surfaces. Altering the structure of the flagellin modification impacted on colonization and disease recurrence in a murine model of infection, showing that alterations in the surface architecture of C. difficile vegetative cells can play a significant role in disease. We show that motility is not a requirement for colonization, but that colonization was compromised when the glycan structure was incomplete.
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Dunne C, Dolan B, Clyne M. Factors that mediate colonization of the human stomach by Helicobacter pylori. World J Gastroenterol 2014; 20:5610-24. [PMID: 24914320 PMCID: PMC4024769 DOI: 10.3748/wjg.v20.i19.5610] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Revised: 12/04/2013] [Accepted: 01/19/2014] [Indexed: 02/06/2023] Open
Abstract
Helicobacter pylori (H. pylori) colonizes the stomach of humans and causes chronic infection. The majority of bacteria live in the mucus layer overlying the gastric epithelial cells and only a small proportion of bacteria are found interacting with the epithelial cells. The bacteria living in the gastric mucus may act as a reservoir of infection for the underlying cells which is essential for the development of disease. Colonization of gastric mucus is likely to be key to the establishment of chronic infection. How H. pylori manages to colonise and survive in the hostile environment of the human stomach and avoid removal by mucus flow and killing by gastric acid is the subject of this review. We also discuss how bacterial and host factors may together go some way to explaining the susceptibility to colonization and the outcome of infection in different individuals. H. pylori infection of the gastric mucosa has become a paradigm for chronic infection. Understanding of why H. pylori is such a successful pathogen may help us understand how other bacterial species colonise mucosal surfaces and cause disease.
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29
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Gram-negative flagella glycosylation. Int J Mol Sci 2014; 15:2840-57. [PMID: 24557579 PMCID: PMC3958885 DOI: 10.3390/ijms15022840] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2014] [Revised: 01/20/2014] [Accepted: 01/27/2014] [Indexed: 01/11/2023] Open
Abstract
Protein glycosylation had been considered as an eccentricity of a few bacteria. However, through advances in analytical methods and genome sequencing, it is now established that bacteria possess both N-linked and O-linked glycosylation pathways. Both glycosylation pathways can modify multiple proteins, flagellins from Archaea and Eubacteria being one of these. Flagella O-glycosylation has been demonstrated in many polar flagellins from Gram-negative bacteria and in only the Gram-positive genera Clostridium and Listeria. Furthermore, O-glycosylation has also been demonstrated in a limited number of lateral flagellins. In this work, we revised the current advances in flagellar glycosylation from Gram-negative bacteria, focusing on the structural diversity of glycans, the O-linked pathway and the biological function of flagella glycosylation.
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Tian W, Jia Y, Yuan K, Huang L, Nadolny C, Dong X, Ren X, Liu J. Serum antibody against Helicobacter pylori FlaA and risk of gastric cancer. Helicobacter 2014; 19:9-16. [PMID: 24118166 DOI: 10.1111/hel.12095] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Helicobacter pylori (H. pylori) infection is a major risk factor for gastric cancer (GC); however, only a minority of infected individuals develops GC. We aim to assess the association between serostatus of antibody against H. pylori flagellin A (FlaA) and risk of GC and to evaluate the value of serum FlaA antibody as a novel screening biomarker for GC risk. METHODS A hospital-based case-control study including 232 cases and 264 controls was conducted. Logistic regression was adopted to analyze the association between the serostatus of FlaA antibody and risk of GC. Serum FlaA antibody was measured by an enzyme-linked immunosorbent assay (ELISA). Receiver operating characteristic (ROC) curve was used to evaluate the screening efficacy and to identify a cutoff point of serum FlaA antibody level. RESULTS Helicobacter pylori infection was associated with an increased risk of GC (p = .007). A positive association between serum FlaA antibody and GC risk was observed in overall subjects and H. pylori-positive subjects (OR [95% CI]: 6.8 [4.3-10.7] and 6.9 [3.6-13.4], respectively; p < .001). The seropositivity of FlaA antibody was strongly related to GC risk in a dose-dependent manner (p for trend < .001). The optimal cutoff value (OD) was 0.1403, providing a sensitivity of 74.1% and a specificity of 64.4%. The area under the ROC curve (AUC) was 0.74 in overall subjects and 0.73 in H. pylori-positive subjects, respectively. CONCLUSIONS FlaA was an independent risk factor for H. pylori-related GC. Serum FlaA antibody may serve as a novel noninvasive biomarker for early detection of GC.
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Affiliation(s)
- Wenjing Tian
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, Heilongjiang Province, China
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31
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Morrison MJ, Imperiali B. The renaissance of bacillosamine and its derivatives: pathway characterization and implications in pathogenicity. Biochemistry 2014; 53:624-38. [PMID: 24383882 PMCID: PMC3951908 DOI: 10.1021/bi401546r] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
![]()
Prokaryote-specific
sugars, including N,N′-diacetylbacillosamine
(diNAcBac) and pseudaminic
acid, have experienced a renaissance in the past decade because of
their discovery in glycans related to microbial pathogenicity. DiNAcBac
is found at the reducing end of oligosaccharides of N- and O-linked
bacterial protein glycosylation pathways of Gram-negative pathogens,
including Campylobacter jejuni and Neisseria
gonorrhoeae. Further derivatization of diNAcBac results in
the nonulosonic acid known as legionaminic acid, which was first characterized
in the O-antigen of the lipopolysaccharide (LPS) in Legionella
pneumophila. Pseudaminic acid, an isomer of legionaminic
acid, is also important in pathogenic bacteria such as Helicobacter
pylori because of its occurrence in O-linked glycosylation
of flagellin proteins, which plays an important role in flagellar
assembly and motility. Here, we present recent advances in the characterization
of the biosynthetic pathways leading to these highly modified sugars
and investigation of the roles that each plays in bacterial fitness
and pathogenicity.
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Affiliation(s)
- Michael J Morrison
- Departments of Chemistry and Biology, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
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32
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Pandey GS, Hang'ombe BM, Mushabati F, Kataba A. Prevalence of tuberculosis among southern Zambian cattle and isolation of Mycobacterium bovis in raw milk obtained from tuberculin positive cows. Vet World 2013. [DOI: 10.14202/vetworld.2013.986-991] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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Rubin EJ, Trent MS. Colonize, evade, flourish: how glyco-conjugates promote virulence of Helicobacter pylori. Gut Microbes 2013; 4:439-53. [PMID: 23859890 PMCID: PMC3928157 DOI: 10.4161/gmic.25721] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Helicobacter pylori is an adapted gastric pathogen that colonizes the human stomach, causing severe gastritis and gastric cancer. A hallmark of infection is the ability of this organism to evade detection by the human immune system. H. pylori has evolved a number of features to achieve this, many of which involve glyco-conjugates including the lipopolysaccharide, peptidoglycan layer, glycoproteins, and glucosylated cholesterol. These major bacterial components possess unique features from those of other gram-negative organisms, including differences in structure, assembly, and modification. These defining characteristics of H. pylori glycobiology help the pathogen establish a long-lived infection by providing camouflage, modulating the host immune response, and promoting virulence mechanisms. In this way, glyco-conjugates are essential for H. pylori pathogenicity and survival, allowing it to carve out a niche in the formidable environment of the human stomach.
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Affiliation(s)
- Erica J Rubin
- Institute for Cellular and Molecular Biology; The University of Texas at Austin; Austin, TX USA
| | - M Stephen Trent
- Institute for Cellular and Molecular Biology; The University of Texas at Austin; Austin, TX USA,Department of Molecular Biosciences; The University of Texas at Austin; Austin, TX USA,Correspondence to: M Stephen Trent,
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34
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Jordan DS, Daubenspeck JM, Laube AH, Renfrow MB, Dybvig K. O-linked protein glycosylation in Mycoplasma. Mol Microbiol 2013; 90:1046-53. [PMID: 24118505 DOI: 10.1111/mmi.12415] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/26/2013] [Indexed: 01/06/2023]
Abstract
Although mycoplasmas have a paucity of glycosyltransferases and nucleotidyltransferases recognizable by bioinformatics, these bacteria are known to produce polysaccharides and glycolipids. We show here that mycoplasmas also produce glycoproteins and hence have glycomes more complex than previously realized. Proteins from several species of Mycoplasma reacted with a glycoprotein stain, and the murine pathogen Mycoplasma arthritidis was chosen for further study. The presence of M. arthritidis glycoproteins was confirmed by high-resolution mass spectrometry. O-linked glycosylation was clearly identified at both serine and threonine residues. No consensus amino acid sequence was evident for the glycosylation sites of the glycoproteins. A single hexose was identified as the O-linked modification, and glucose was inferred by (13) C-labelling to be the hexose at several of the glycosylation sites. This is the first study to conclusively identify sites of protein glycosylation in any of the mollicutes.
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Affiliation(s)
- David S Jordan
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
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35
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Sycuro LK, Rule CS, Petersen TW, Wyckoff TJ, Sessler T, Nagarkar DB, Khalid F, Pincus Z, Biboy J, Vollmer W, Salama NR. Flow cytometry-based enrichment for cell shape mutants identifies multiple genes that influence Helicobacter pylori morphology. Mol Microbiol 2013; 90:869-83. [PMID: 24112477 PMCID: PMC3844677 DOI: 10.1111/mmi.12405] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/17/2013] [Indexed: 12/17/2022]
Abstract
The helical cell shape of Helicobacter pylori is highly conserved and contributes to its ability to swim through and colonize the viscous gastric mucus layer. A multi-faceted peptidoglycan (PG) modification programme involving four recently characterized peptidases and two accessory proteins is essential for maintaining H. pylori's helicity. To expedite identification of additional shape-determining genes, we employed flow cytometry with fluorescence-activated cell sorting (FACS) to enrich a transposon library for bacterial cells with altered light scattering profiles that correlate with perturbed cell morphology. After a single round of sorting, 15% of our clones exhibited a stable cell shape defect, reflecting 37-fold enrichment. Sorted clones with straight rod morphology contained insertions in known PG peptidases, as well as an insertion in csd6, which we demonstrated has ld-carboxypeptidase activity and cleaves monomeric tetrapeptides in the PG sacculus, yielding tripeptides. Other mutants had only slight changes in helicity due to insertions in genes encoding MviN/MurJ, a protein possibly involved in initiating PG synthesis, and the hypothetical protein HPG27_782. Our findings demonstrate FACS robustly detects perturbations of bacterial cell shape and identify additional PG peptide modifications associated with helical cell shape in H. pylori.
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Affiliation(s)
- Laura K Sycuro
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
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Musumeci MA, Faridmoayer A, Watanabe Y, Feldman MF. Evaluating the role of conserved amino acids in bacterial O-oligosaccharyltransferases by in vivo, in vitro and limited proteolysis assays. Glycobiology 2013; 24:39-50. [DOI: 10.1093/glycob/cwt087] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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Asakura H, Hashii N, Uema M, Kawasaki N, Sugita-Konishi Y, Igimi S, Yamamoto S. Campylobacter jejuni pdxA affects flagellum-mediated motility to alter host colonization. PLoS One 2013; 8:e70418. [PMID: 23936426 PMCID: PMC3735588 DOI: 10.1371/journal.pone.0070418] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2013] [Accepted: 06/24/2013] [Indexed: 11/18/2022] Open
Abstract
Vitamin B6 (pyridoxal-5'-phosphate, PLP) is linked to a variety of biological functions in prokaryotes. Here, we report that the pdxA (putative 4-hydroxy-L-threonine phosphate dehydrogenase) gene plays a pivotal role in the PLP-dependent regulation of flagellar motility, thereby altering host colonization in a leading foodborne pathogen, Campylobacter jejuni. A C. jejuni pdxA mutant failed to produce PLP and exhibited a coincident loss of flagellar motility. Mass spectrometric analyses showed a 3-fold reduction in the main flagellar glycan pseudaminic acid (Pse) associated with the disruption of pdxA. The pdxA mutant also exhibited reduced growth rates compared with the WT strain. Comparative metabolomic analyses revealed differences in respiratory/energy metabolism between WT C. jejuni and the pdxA mutant, providing a possible explanation for the differential growth fitness between the two strains. Consistent with the lack of flagellar motility, the pdxA mutant showed impaired motility-mediated responses (bacterial adhesion, ERK1/2 activation, and IL-8 production) in INT407 cells and reduced colonization of chickens compared with the WT strain. Overall, this study demonstrated that the pdxA gene affects the PLP-mediated flagellar motility function, mainly through alteration of Pse modification, and the disruption of this gene also alters the respiratory/energy metabolisms to potentially affect host colonization. Our data therefore present novel implications regarding the utility of PLP and its dependent enzymes as potent target(s) for the control of this pathogen in the poultry host.
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Affiliation(s)
- Hiroshi Asakura
- Division of Biomedical Food Research, National Institute of Health Sciences, Setagaya-ku, Tokyo, Japan.
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Belogolova E, Bauer B, Pompaiah M, Asakura H, Brinkman V, Ertl C, Bartfeld S, Nechitaylo TY, Haas R, Machuy N, Salama N, Churin Y, Meyer TF. Helicobacter pylori outer membrane protein HopQ identified as a novel T4SS-associated virulence factor. Cell Microbiol 2013; 15:1896-912. [PMID: 23782461 DOI: 10.1111/cmi.12158] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Revised: 06/11/2013] [Accepted: 06/11/2013] [Indexed: 12/13/2022]
Abstract
Helicobacter pylori is a bacterial pathogen that colonizes the gastric niche of ∼ 50% of the human population worldwide and is known to cause peptic ulceration and gastric cancer. Pathology of infection strongly depends on a cag pathogenicity island (cagPAI)-encoded type IV secretion system (T4SS). Here, we aimed to identify as yet unknown bacterial factors involved in cagPAI effector function and performed a large-scale screen of an H. pylori transposon mutant library using activation of the pro-inflammatory transcription factor NF-κB in human gastric epithelial cells as a measure of T4SS function. Analysis of ∼ 3000 H. pylori mutants revealed three non-cagPAI genes that affected NF-κB nuclear translocation. Of these, the outer membrane protein HopQ from H. pylori strain P12 was essential for CagA translocation and for CagA-mediated host cell responses such as formation of the hummingbird phenotype and cell scattering. Besides that, deletion of hopQ reduced T4SS-dependent activation of NF-κB, induction of MAPK signalling and secretion of interleukin 8 (IL-8) in the host cells, but did not affect motility or the quantity of bacteria attached to host cells. Hence, we identified HopQ as a non-cagPAI-encoded cofactor of T4SS function.
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Affiliation(s)
- Elena Belogolova
- Department of Molecular Biology, Max Planck Institute for Infection Biology, D-10117, Berlin, Germany
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Musumeci MA, Hug I, Scott NE, Ielmini MV, Foster LJ, Wang PG, Feldman MF. In vitro activity of Neisseria meningitidis PglL O-oligosaccharyltransferase with diverse synthetic lipid donors and a UDP-activated sugar. J Biol Chem 2013; 288:10578-87. [PMID: 23460642 DOI: 10.1074/jbc.m112.432815] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Oligosaccharyltransferases (OTases) are enzymes that catalyze the transfer of an oligosaccharide from a lipid carrier to an acceptor molecule, commonly a protein. OTases are classified as N-OTases and O-OTases, depending on the nature of the glycosylation reaction. The N-OTases catalyze the glycan transfer to amide groups in asparagines in a reaction named N-linked glycosylation. The O-OTases are responsible for protein O-linked glycosylation, which involves the attachment of glycans to hydroxyl groups of serine or threonine residues. These enzymes exhibit a relaxed specificity and are able to transfer a variety of glycan structures to different protein acceptors. This property confers OTases with great biotechnological potential as these enzymes can produce glycoconjugates relevant to the pharmaceutical industry. Furthermore, OTases are thought to be involved in pathogenesis mechanisms. Several aspects of the functionality of OTases are not fully understood. In this work, we developed a novel approach to perform kinetic studies on PglL, the O-OTase from Neisseria meningitidis. We investigated the importance of the acyl moiety of the lipid glycan donor substrate on the functionality of PglL by testing the efficiency of glycosylation reactions using synthetic substrates carrying the same glycan structure but different acyl moieties. We found that PglL can function with many lipids as glycan donors, although the length and the conformation of the lipid moiety significantly influenced the catalytic efficiency. Interestingly, PglL was also able to transfer a monosaccharide employing its nucleotide-activated form, acting as a Leloir glycosyltransferase. These results provide new insights on the function and the evolution of oligosaccharyltransferases.
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Affiliation(s)
- Matias A Musumeci
- Alberta Glycomics Centre, Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
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Kao CY, Sheu BS, Sheu SM, Yang HB, Chang WL, Cheng HC, Wu JJ. Higher motility enhances bacterial density and inflammatory response in dyspeptic patients infected with Helicobacter pylori. Helicobacter 2012; 17:411-6. [PMID: 23066970 DOI: 10.1111/j.1523-5378.2012.00974.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Motility mediated by the flagella of Helicobacter pylori is important for the cells to move toward the gastric mucus in niches adjacent to the epithelium; then, H. pylori uses the adhesin SabA to interact with sialyl-Le(x) on inflammatory host cells for persistent infection. Here, we reveal the clinical association of bacterial motility, SabA expression, and pathological outcomes. METHODS Ninety-six clinical isolates were screened for bacterial motility, and the expression of SabA of each isolate was confirmed by Western blotting. H. pylori-infected patients were assessed for their bacterial density, sialyl-Le(x) expression, inflammatory scores, and clinical diseases. RESULTS The mean diameter in the motility assay was 17 mm, and eight (8.3%) of the strains had impaired motility, with a diameter <5 mm. H. pylori density in cardia, the acute inflammatory score in the body locus, and the prevalence rate of gastric atrophy were increased in patients infected with higher-motility strains (p = .023, <.001, or <.001, respectively). The total inflammatory scores (both acute and chronic) and bacterial density dramatically increased in patients expressing the sialyl-Le(x) antigen and infected with higher-motility, SabA-positive H. pylori (p = .016, .01, or .005, respectively). CONCLUSION These results suggest that the higher motility of H. pylori enhances pathological outcomes, and the SabA-sialyl-Le(x) interaction has a synergistic effect on virulence of the higher-motility strains.
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Affiliation(s)
- Cheng-Yen Kao
- Institute of Basic Medical Sciences, College of Medicine, National Cheng-Kung University, Tainan, Taiwan
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41
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Roszczenko P, Radomska KA, Wywial E, Collet JF, Jagusztyn-Krynicka EK. A novel insight into the oxidoreductase activity of Helicobacter pylori HP0231 protein. PLoS One 2012; 7:e46563. [PMID: 23056345 PMCID: PMC3463561 DOI: 10.1371/journal.pone.0046563] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2012] [Accepted: 08/31/2012] [Indexed: 12/16/2022] Open
Abstract
Background The formation of a disulfide bond between two cysteine residues stabilizes protein structure. Although we now have a good understanding of the Escherichia coli disulfide formation system, the machineries at work in other bacteria, including pathogens, are poorly characterized. Thus, the objective of this work was to improve our understanding of the disulfide formation machinery of Helicobacter pylori, a leading cause of ulcers and a risk factor for stomach cancer worldwide. Methods and Results The protein HP0231 from H. pylori, a structural counterpart of E. coli DsbG, is the focus of this research. Its function was clarified by using a combination of biochemical, microbiological and genetic approaches. In particular, we determined the biochemical properties of HP0231 as well as its redox state in H. pylori cells. Conclusion Altogether our results show that HP0231 is an oxidoreductase that catalyzes disulfide bond formation in the periplasm. We propose to call it HpDsbA.
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Affiliation(s)
- Paula Roszczenko
- Department of Bacterial Genetics, Institute of Microbiology, the University of Warsaw, Warsaw, Poland
- College of Inter-Faculty Individual Studies in Mathematics and Natural Sciences, the University of Warsaw, Warsaw, Poland
| | - Katarzyna A. Radomska
- Department of Bacterial Genetics, Institute of Microbiology, the University of Warsaw, Warsaw, Poland
| | - Ewa Wywial
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Jean-Francois Collet
- WELBIO (Walloon Excellence in Life Sciences and Biotechnology), Université Catholique de Louvain, Brussels, Belgium
- de Duve Institute, Université Catholique de Louvain, Brussels, Belgium
- Brussels Center for Redox Biology, Brussels, Belgium
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Ricaldi JN, Matthias MA, Vinetz JM, Lewis AL. Expression of sialic acids and other nonulosonic acids in Leptospira. BMC Microbiol 2012; 12:161. [PMID: 22853805 PMCID: PMC3438082 DOI: 10.1186/1471-2180-12-161] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Accepted: 07/19/2012] [Indexed: 12/17/2022] Open
Abstract
Background Sialic acids are negatively charged nine carbon backbone sugars expressed on mammalian cell surfaces. Sialic acids are part of a larger family of nonulosonic acid (NulO) molecules that includes pseudaminic and legionaminic acids. Microbial expression of sialic acids and other nonulosonic acids has been shown to contribute to host-microbe interactions in a variety of contexts, including participation in colonization, immune subversion, and behaviors such as biofilm formation, autoagglutination and motility. Previous research has suggested that some spirochetes may also express these molecules. Results Here we use a combination of molecular tools to investigate the presence of NulO biosynthetic gene clusters among clinical and saprophytic isolates of the genus Leptospira. Polymerase chain reaction and Southern blotting suggested that a variety of leptospires encoded NulO biosynthetic pathways. High performance liquid chromatography and mass spectrometry analyses provided biochemical evidence that di-N-acetylated NulO molecules are expressed at relatively high levels by L. interrogans serovar Lai strain 55601, and at lower levels by L. alexanderi serovar Manhao and L. fainei serovar Hurstbridge. Endogenous expression of N-acetylneuraminic acid (Neu5Ac, the most common sialic acid) was documented in L. interrogans serovar Copenhageni strain L1-130. Neu5Ac biosynthesis is also supported by a unique gene fusion event resulting in an enzyme with an N-terminal N-acetylneuraminic acid synthase domain and a C-terminal phosphatase domain. This gene fusion suggests that L. interrogans uses a Neu5Ac biosynthetic pathway more similar to animals than to other bacteria. Analysis of the composition and phylogeny of putative NulO biosynthetic gene clusters in L. interrogans serovar Lai and serovar Copenhageni revealed that both strains have complete biosynthetic pathways for legionamimic acid synthesis, a molecule with the same stereochemistry as sialic acid. Lectin-based affinity purification of NulO-modified molecules, followed by mass spectrometric identification suggests post-translational modification of surface lipoproteins, including Loa22. Conclusions Leptospira species encode NulO biosynthetic pathways and synthesize multiple NulO molecules including sialic acid. Additional studies are needed to clarify the exact context and functional significance of NulO expression. These findings have implications for immune evasion during systemic leptospirosis.
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Affiliation(s)
- Jessica N Ricaldi
- Department of Medicine, Division of Infectious Diseases, University of California San Diego, School of Medicine, La Jolla, CA 92093, USA
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Hypomorphic glycosyltransferase alleles and recoding at contingency loci influence glycan microheterogeneity in the protein glycosylation system of Neisseria species. J Bacteriol 2012; 194:5034-43. [PMID: 22797763 DOI: 10.1128/jb.00950-12] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
As more bacterial protein glycosylation systems are identified and characterized, a central question that arises is, what governs the prevalence of particular glycans associated with them? In addition, accumulating evidence shows that bacterial protein glycans can be subject to the phenomenon of microheterogeneity, in which variant glycan structures are found at specific attachment sites of a given glycoprotein. Although factors underlying microheterogeneity in reconstituted expression systems have been identified and modeled, those impacting natural systems largely remain enigmatic. On the basis of a sensitive and specific glycan serotyping system, microheterogeneity has been reported for the broad-spectrum, O-linked protein glycosylation system in species within the genus Neisseria. To elucidate the mechanisms involved, a genetic approach was used to identify a hypomorphic allele of pglA (encoding the PglA galactosyltransferase) as a significant contributor to simultaneous expression of multiple glycoforms. Moreover, this phenotype was mapped to a single amino acid polymorphism in PglA. Further analyses revealed that many pglA phase-off variants (containing out-of-frame configurations in simple nucleotide repeats within the open reading frame) were associated with disproportionally high levels of the N,N'-diacetylbacillosamine-Gal disaccharide glycoform generated by PglA. This phenotype is emblematic of nonstandard decoding involving programmed ribosomal frameshifting and/or programmed transcriptional realignment. Together, these findings provide new information regarding the mechanisms of neisserial protein glycan microheterogeneity and the anticipatory nature of contingency loci.
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Zhang WJ, Santini CL, Bernadac A, Ruan J, Zhang SD, Kato T, Li Y, Namba K, Wu LF. Complex spatial organization and flagellin composition of flagellar propeller from marine magnetotactic ovoid strain MO-1. J Mol Biol 2012; 416:558-70. [PMID: 22245577 DOI: 10.1016/j.jmb.2011.12.065] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Revised: 12/15/2011] [Accepted: 12/30/2011] [Indexed: 12/24/2022]
Abstract
Marine magnetotactic ovoid bacterium MO-1 is capable of swimming along the geomagnetic field lines by means of its two sheathed flagellar bundles at a speed up to 300 μm/s. In this study, by using electron microscopy, we showed that, in each bundle, six individual flagella were organized in hexagon with a seventh in the middle. We identified 12 flagellin paralogs and 2 putative flagellins in the genome of MO-1. Among them, 13 were tandemly located on an ~ 17-kb segment while the 14th was on a separated locus. Using reverse transcription PCR and quantitative PCR, we found that all the 14 flagellin or putative flagellin genes were transcribed and that 2 of them were more abundantly expressed than others. A nLC (nanoliquid chromatography)-ESI (electrospray ionization)-MS/MS (mass spectrometry/mass spectrometry) mass spectrometry analysis identified all the 12 flagellin proteins in three glycosylated polypeptide bands resolved by one-dimensional denaturing polyacrylamide gel electrophoresis and 10 of them in 21 spots obtained by means of two-dimensional electrophoresis of flagellar extracts. Most spots contained more than one flagellin, and eight of the ten identified flagellins existed in multiple isoforms. Taken together, these results show unprecedented complexity in the spatial organization and flagellin composition of the flagellar propeller. Such architecture is observed only for ovoid-coccoid, bilophotrichously flagellated magnetotactic bacteria living in marine sediments, suggesting a species and environmental specificity.
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Affiliation(s)
- Wei-Jia Zhang
- State Key Laboratories for Agrobiotechnology and College of Biological Sciences, China Agricultural University, Beijing 100193, China
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Yoon JY, Kim J, Lee SJ, Kim HS, Im HN, Yoon HJ, Kim KH, Kim SJ, Han BW, Suh SW. Structural and functional characterization of Helicobacter pylori DsbG. FEBS Lett 2011; 585:3862-7. [PMID: 22062156 DOI: 10.1016/j.febslet.2011.10.042] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Revised: 10/24/2011] [Accepted: 10/24/2011] [Indexed: 12/16/2022]
Abstract
Dsb proteins play important roles in bacterial pathogenicity. To better understand the role of Dsb proteins in Helicobacter pylori, we have structurally and functionally characterized H. pylori DsbG (HP0231). The monomer consists of two domains connected by a helical linker. Two monomers associate to form a V-shaped dimer. The monomeric and dimeric structures of H. pylori DsbG show significant differences compared to Escherichia coli DsbG. Two polyethylene glycol molecules are bound in the cleft of the V-shaped dimer, suggesting a possible role as a chaperone. Furthermore, we show that H. pylori DsbG functions as a reductase against HP0518, a putative L,D-transpeptidase with a catalytic cysteine residue.
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Affiliation(s)
- Ji Young Yoon
- Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul, Republic of Korea
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