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Gibson K, Chu JK, Zhu S, Nguyen D, Mrázek J, Liu J, Hoover TR. A Tripartite Efflux System Affects Flagellum Stability in Helicobacter pylori. Int J Mol Sci 2022; 23:ijms231911609. [PMID: 36232924 PMCID: PMC9570263 DOI: 10.3390/ijms231911609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 09/23/2022] [Accepted: 09/29/2022] [Indexed: 11/07/2022] Open
Abstract
Helicobacter pylori uses a cluster of polar, sheathed flagella for swimming motility. A search for homologs of H. pylori proteins that were conserved in Helicobacter species that possess flagellar sheaths but were underrepresented in Helicobacter species with unsheathed flagella identified several candidate proteins. Four of the identified proteins are predicted to form part of a tripartite efflux system that includes two transmembrane domains of an ABC transporter (HP1487 and HP1486), a periplasmic membrane fusion protein (HP1488), and a TolC-like outer membrane efflux protein (HP1489). Deleting hp1486/hp1487 and hp1489 homologs in H. pylori B128 resulted in reductions in motility and the number of flagella per cell. Cryo-electron tomography studies of intact motors of the Δhp1489 and Δhp1486/hp1487 mutants revealed many of the cells contained a potential flagellum disassembly product consisting of decorated L and P rings, which has been reported in other bacteria. Aberrant motors lacking specific components, including a cage-like structure that surrounds the motor, were also observed in the Δhp1489 mutant. These findings suggest a role for the H. pylori HP1486-HP1489 tripartite efflux system in flagellum stability. Three independent variants of the Δhp1486/hp1487 mutant with enhanced motility were isolated. All three motile variants had the same frameshift mutation in fliL, suggesting a role for FliL in flagellum disassembly.
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Affiliation(s)
- Katherine Gibson
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
| | - Joshua K. Chu
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
| | - Shiwei Zhu
- Microbial Sciences Institute, Yale University, West Haven, CT 06516, USA
- Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, CT 06536, USA
| | - Doreen Nguyen
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
| | - Jan Mrázek
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
- Institute of Bioinformatics, University of Georgia, Athens, GA 30602, USA
| | - Jun Liu
- Microbial Sciences Institute, Yale University, West Haven, CT 06516, USA
- Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, CT 06536, USA
| | - Timothy R. Hoover
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
- Correspondence: ; Tel.: +1-706-542-2675
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Cain JA, Dale AL, Cordwell SJ. Exploiting pglB Oligosaccharyltransferase-Positive and -Negative Campylobacter jejuni and a Multiprotease Digestion Strategy to Identify Novel Sites Modified by N-Linked Protein Glycosylation. J Proteome Res 2021; 20:4995-5009. [PMID: 34677046 DOI: 10.1021/acs.jproteome.1c00482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Campylobacter jejuni is a bacterial pathogen encoding a unique N-linked glycosylation (pgl) system that mediates attachment of a heptasaccharide to N-sequon-containing membrane proteins by the PglB oligosaccharyltransferase (OST). Many targets of PglB are known, yet only a fraction of sequons are experimentally confirmed, and site occupancy remains elusive. We exploited pglB-positive (wild-type; WT) and -negative (ΔpglB) proteomes to identify potential glycosites. The nonglycosylated forms of known glycopeptides were typically increased in protein normalized abundance in ΔpglB relative to WT and restored by pglB reintroduction (ΔpglB::pglB). Sequon-containing peptide abundances were thus consistent with significant site occupancy in the presence of the OST. Peptides with novel sequons were either unaltered (likely not glycosylated) or showed abundance consistent with known glycopeptides. Topology analysis revealed that unaltered sequons often displayed cytoplasmic localization, despite originating from membrane proteins. Novel glycosites were confirmed using parallel multiprotease digestion, LC-MS/MS, and FAIMS-MS to define the glycoproteomes of WT and ΔpglB::pglB C. jejuni. We identified 142 glycosites, of which 32 were novel, and 83% of sites predicted by proteomics were validated. There are now 166 experimentally verified C. jejuni glycosites and evidence for occupancy or nonoccupancy of 31 additional sites. This study serves as a model for the use of OST-negative cells and proteomics for highlighting novel glycosites and determining occupancy in a range of organisms.
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Affiliation(s)
- Joel A Cain
- Charles Perkins Centre, The University of Sydney, Sydney 2006, Australia.,School of Life and Environmental Sciences, The University of Sydney, Sydney 2006, Australia
| | - Ashleigh L Dale
- Charles Perkins Centre, The University of Sydney, Sydney 2006, Australia.,School of Life and Environmental Sciences, The University of Sydney, Sydney 2006, Australia
| | - Stuart J Cordwell
- Charles Perkins Centre, The University of Sydney, Sydney 2006, Australia.,School of Life and Environmental Sciences, The University of Sydney, Sydney 2006, Australia.,Sydney Mass Spectrometry, The University of Sydney, Sydney 2006, Australia
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3
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Panzenhagen P, Portes AB, dos Santos AMP, Duque SDS, Conte Junior CA. The Distribution of Campylobacter jejuni Virulence Genes in Genomes Worldwide Derived from the NCBI Pathogen Detection Database. Genes (Basel) 2021; 12:1538. [PMID: 34680933 PMCID: PMC8535712 DOI: 10.3390/genes12101538] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 09/26/2021] [Accepted: 09/27/2021] [Indexed: 01/01/2023] Open
Abstract
Campylobacter jejuni (C. jejuni) is responsible for 80% of human campylobacteriosis and is the leading cause of gastroenteritis globally. The relevant public health risks of C. jejuni are caused by particular virulence genes encompassing its virulome. We analyzed 40,371 publicly available genomes of C. jejuni deposited in the NCBI Pathogen Detection Database, combining their epidemiologic metadata with an in silico bioinformatics analysis to increase our current comprehension of their virulome from a global perspective. The collection presented a virulome composed of 126 identified virulence factors that were grouped in three clusters representing the accessory, the softcore, and the essential core genes according to their prevalence within the genomes. The multilocus sequence type distribution in the genomes was also investigated. An unexpected low prevalence of the full-length flagellin flaA and flaB locus of C. jejuni genomes was revealed, and an essential core virulence gene repertoire prevalent in more than 99.99% of genomes was identified. Altogether, this is a pioneer study regarding Campylobacter jejuni that has compiled a significant amount of data about the Multilocus Sequence Type and virulence factors concerning their global prevalence and distribution over this database.
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Affiliation(s)
- Pedro Panzenhagen
- Center for Food Analysis (NAL), Technological Development Support Laboratory (LADETEC), Federal University of Rio de Janeiro (UFRJ), Cidade Universitária, Rio de Janeiro 21941-598, RJ, Brazil; (A.B.P.); (A.M.P.d.S.); (C.A.C.J.)
- Laboratory of Advanced Analysis in Biochemistry and Molecular Biology (LAABBM), Department of Biochemistry, Federal University of Rio de Janeiro (UFRJ), Cidade Universitária, Rio de Janeiro 21941-909, RJ, Brazil
| | - Ana Beatriz Portes
- Center for Food Analysis (NAL), Technological Development Support Laboratory (LADETEC), Federal University of Rio de Janeiro (UFRJ), Cidade Universitária, Rio de Janeiro 21941-598, RJ, Brazil; (A.B.P.); (A.M.P.d.S.); (C.A.C.J.)
- Laboratory of Advanced Analysis in Biochemistry and Molecular Biology (LAABBM), Department of Biochemistry, Federal University of Rio de Janeiro (UFRJ), Cidade Universitária, Rio de Janeiro 21941-909, RJ, Brazil
| | - Anamaria M. P. dos Santos
- Center for Food Analysis (NAL), Technological Development Support Laboratory (LADETEC), Federal University of Rio de Janeiro (UFRJ), Cidade Universitária, Rio de Janeiro 21941-598, RJ, Brazil; (A.B.P.); (A.M.P.d.S.); (C.A.C.J.)
- Laboratory of Advanced Analysis in Biochemistry and Molecular Biology (LAABBM), Department of Biochemistry, Federal University of Rio de Janeiro (UFRJ), Cidade Universitária, Rio de Janeiro 21941-909, RJ, Brazil
| | - Sheila da Silva Duque
- Collection of Campylobacter, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro 21040-900, RJ, Brazil;
| | - Carlos Adam Conte Junior
- Center for Food Analysis (NAL), Technological Development Support Laboratory (LADETEC), Federal University of Rio de Janeiro (UFRJ), Cidade Universitária, Rio de Janeiro 21941-598, RJ, Brazil; (A.B.P.); (A.M.P.d.S.); (C.A.C.J.)
- Laboratory of Advanced Analysis in Biochemistry and Molecular Biology (LAABBM), Department of Biochemistry, Federal University of Rio de Janeiro (UFRJ), Cidade Universitária, Rio de Janeiro 21941-909, RJ, Brazil
- Graduate Program in Food Science (PPGCAL), Institute of Chemistry (IQ), Federal University of Rio de Janeiro (UFRJ), Cidade Universitária, Rio de Janeiro 21941-909, RJ, Brazil
- Graduate Program in Veterinary Hygiene (PPGHV), Faculty of Veterinary Medicine, Fluminense Federal University (UFF), Vital Brazil Filho, Niterói 24230-340, RJ, Brazil
- Graduate Program in Sanitary Surveillance (PPGVS), National Institute of Health Quality Control (INCQS), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro 21040-900, RJ, Brazil
- Graduate Program in Chemistry (PGQu), Institute of Chemistry (IQ), Federal University of Rio de Janeiro (UFRJ), Cidade Universitária, Rio de Janeiro 21941-909, RJ, Brazil
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Cayrou C, Barratt NA, Ketley JM, Bayliss CD. Phase Variation During Host Colonization and Invasion by Campylobacter jejuni and Other Campylobacter Species. Front Microbiol 2021; 12:705139. [PMID: 34394054 PMCID: PMC8355987 DOI: 10.3389/fmicb.2021.705139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 07/09/2021] [Indexed: 11/13/2022] Open
Abstract
Phase variation (PV) is a phenomenon common to a variety of bacterial species for niche adaption and survival in challenging environments. Among Campylobacter species, PV depends on the presence of intergenic and intragenic hypermutable G/C homopolymeric tracts. The presence of phase-variable genes is of especial interest for species that cause foodborne or zoonotic infections in humans. PV influences the formation and the structure of the lipooligosaccharide, flagella, and capsule in Campylobacter species. PV of components of these molecules is potentially important during invasion of host tissues, spread within hosts and transmission between hosts. Motility is a critical phenotype that is potentially modulated by PV. Variation in the status of the phase-variable genes has been observed to occur during colonization in chickens and mouse infection models. Interestingly, PV is also involved in bacterial survival of attack by bacteriophages even during chicken colonization. This review aims to explore and discuss observations of PV during model and natural infections by Campylobacter species and how PV may affect strategies for fighting infections by this foodborne pathogen.
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Affiliation(s)
- Caroline Cayrou
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Natalie A Barratt
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Julian M Ketley
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Christopher D Bayliss
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
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Cain JA, Dale AL, Sumer-Bayraktar Z, Solis N, Cordwell SJ. Identifying the targets and functions of N-linked protein glycosylation in Campylobacter jejuni. Mol Omics 2021; 16:287-304. [PMID: 32347268 DOI: 10.1039/d0mo00032a] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Campylobacter jejuni is a major cause of bacterial gastroenteritis in humans that is primarily associated with the consumption of inadequately prepared poultry products, since the organism is generally thought to be asymptomatic in avian species. Unlike many other microorganisms, C. jejuni is capable of performing extensive post-translational modification (PTM) of proteins by N- and O-linked glycosylation, both of which are required for optimal chicken colonization and human virulence. The biosynthesis and attachment of N-glycans to C. jejuni proteins is encoded by the pgl (protein glycosylation) locus, with the PglB oligosaccharyltransferase (OST) enabling en bloc transfer of a heptasaccharide N-glycan from a lipid carrier in the inner membrane to proteins exposed within the periplasm. Seventy-eight C. jejuni glycoproteins (represented by 134 sites of experimentally verified N-glycosylation) have now been identified, and include inner and outer membrane proteins, periplasmic proteins and lipoproteins, which are generally of poorly defined or unknown function. Despite our extensive knowledge of the targets of this apparently widespread process, we still do not fully understand the role N-glycosylation plays biologically, although several phenotypes, including wild-type stress resistance, biofilm formation, motility and chemotaxis have been related to a functional pgl system. Recent work has described enzymatic processes (nitrate reductase NapAB) and antibiotic efflux (CmeABC) as major targets requiring N-glycan attachment for optimal function, and experimental evidence also points to roles in cell binding via glycan-glycan interactions, protein complex formation and protein stability by conferring protection against host and bacterial proteolytic activity. Here we examine the biochemistry of the N-linked glycosylation system, define its currently known protein targets and discuss evidence for the structural and functional roles of this PTM in individual proteins and globally in C. jejuni pathogenesis.
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Affiliation(s)
- Joel A Cain
- School of Life and Environmental Sciences, The University of Sydney, 2006, Australia and Charles Perkins Centre, The University of Sydney, Level 4 East, The Hub Building (D17), 2006, Australia.
| | - Ashleigh L Dale
- School of Life and Environmental Sciences, The University of Sydney, 2006, Australia and Charles Perkins Centre, The University of Sydney, Level 4 East, The Hub Building (D17), 2006, Australia.
| | - Zeynep Sumer-Bayraktar
- School of Life and Environmental Sciences, The University of Sydney, 2006, Australia and Charles Perkins Centre, The University of Sydney, Level 4 East, The Hub Building (D17), 2006, Australia.
| | - Nestor Solis
- School of Life and Environmental Sciences, The University of Sydney, 2006, Australia
| | - Stuart J Cordwell
- School of Life and Environmental Sciences, The University of Sydney, 2006, Australia and Charles Perkins Centre, The University of Sydney, Level 4 East, The Hub Building (D17), 2006, Australia. and Discipline of Pathology, School of Medical Sciences, The University of Sydney, 2006, Australia and Sydney Mass Spectrometry, The University of Sydney, 2006, Australia
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Yang K, Kao C, Su MS, Wang S, Chen Y, Hu S, Chen J, Teng C, Tsai P, Wu J. Glycosyltransferase Jhp0106 (PseE) contributes to flagellin maturation in Helicobacter pylori. Helicobacter 2021; 26:e12787. [PMID: 33586844 PMCID: PMC7988653 DOI: 10.1111/hel.12787] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 01/26/2021] [Accepted: 01/26/2021] [Indexed: 01/25/2023]
Abstract
BACKGROUND Flagella-mediated motility is both a crucial virulence determinant of Helicobacter pylori and a factor associated with gastrointestinal diseases. Flagellar formation requires flagellins to be glycosylated with pseudaminic acid (Pse), a process that has been extensively studied. However, the transfer of Pse to flagellins remains poorly understood. Therefore, the aim of this study is to characterize a putative glycosyltransferase jhp0106 in flagellar formation. MATERIALS AND METHODS Western blotting and chemical deglycosylation were performed to examine FlaA glycosylation. Protein structural analyses were executed to identify the active site residues of Jhp0106, while the Jhp0106-FlaA interaction was examined using a bacterial two-hybrid assay. Lastly, site-directed mutants with mutated active site residues in the jhp0106 gene were generated and investigated using a motility assay, Western blotting, cDNA-qPCR analysis, and electron microscopic examination. RESULTS Loss of flagellar formation in the Δjhp0106 mutant was confirmed to be associated with non-glycosylated FlaA. Furthermore, three active site residues of Jhp0106 (S350, F376, and E415) were identified within a potential substrate-binding region. The interaction between FlaA and Jhp0106, Jhp0106::S350A, Jhp0106::F376A, or Jhp0106::E415A was determined to be significant. As well, the substitution of S350A, F376A, or E415A in the site-directed Δjhp0106 mutants resulted in impaired motility, deficient FlaA glycosylation, and lacking flagella. However, these phenotypic changes were regardless of flaA expression, implying an indefinite proteolytic degradation of FlaA occurred. CONCLUSIONS This study demonstrated that Jhp0106 (PseE) binds to FlaA mediating FlaA glycosylation and flagellar formation. Our discovery of PseE has revealed a new glycosyltransferase family responsible for flagellin glycosylation in pathogens.
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Affiliation(s)
- Kai‐Yuan Yang
- Institute of Microbiology and ImmunologySchool of Life ScienceNational Yang‐Ming UniversityTaipeiTaiwan
| | - Cheng‐Yen Kao
- Institute of Microbiology and ImmunologySchool of Life ScienceNational Yang‐Ming UniversityTaipeiTaiwan,Department of Biotechnology and Laboratory Science in MedicineSchool of Biomedical Science and EngineeringNational Yang‐Ming UniversityTaipeiTaiwan
| | - Marcia Shu‐Wei Su
- Department of Biotechnology and Laboratory Science in MedicineSchool of Biomedical Science and EngineeringNational Yang‐Ming UniversityTaipeiTaiwan
| | - Shuying Wang
- Department of Microbiology and ImmunologyCollege of MedicineNational Cheng‐Kung UniversityTainanTaiwan
| | - Yueh‐Lin Chen
- Department of Biotechnology and Laboratory Science in MedicineSchool of Biomedical Science and EngineeringNational Yang‐Ming UniversityTaipeiTaiwan
| | - Shiau‐Ting Hu
- Institute of Microbiology and ImmunologySchool of Life ScienceNational Yang‐Ming UniversityTaipeiTaiwan
| | - Jenn‐Wei Chen
- Department of Microbiology and ImmunologyCollege of MedicineNational Cheng‐Kung UniversityTainanTaiwan
| | - Ching‐Hao Teng
- Institute of Molecular MedicineCollege of MedicineNational Cheng Kung UniversityTainanTaiwan
| | - Pei‐Jane Tsai
- Department of Medical Laboratory Science and BiotechnologyCollege of MedicineNational Cheng Kung UniversityTainanTaiwan
| | - Jiunn‐Jong Wu
- Department of Biotechnology and Laboratory Science in MedicineSchool of Biomedical Science and EngineeringNational Yang‐Ming UniversityTaipeiTaiwan
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Chidwick HS, Flack EKP, Keenan T, Walton J, Thomas GH, Fascione MA. Reconstitution and optimisation of the biosynthesis of bacterial sugar pseudaminic acid (Pse5Ac7Ac) enables preparative enzymatic synthesis of CMP-Pse5Ac7Ac. Sci Rep 2021; 11:4756. [PMID: 33637817 PMCID: PMC7910423 DOI: 10.1038/s41598-021-83707-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 02/05/2021] [Indexed: 11/23/2022] Open
Abstract
Pseudaminic acids present on the surface of pathogenic bacteria, including gut pathogens Campylobacter jejuni and Helicobacter pylori, are postulated to play influential roles in the etiology of associated infectious diseases through modulating flagella assembly and recognition of bacteria by the human immune system. Yet they are underexplored compared to other areas of glycoscience, in particular enzymes responsible for the glycosyltransfer of these sugars in bacteria are still to be unambiguously characterised. This can be largely attributed to a lack of access to nucleotide-activated pseudaminic acid glycosyl donors, such as CMP-Pse5Ac7Ac. Herein we reconstitute the biosynthesis of Pse5Ac7Ac in vitro using enzymes from C. jejuni (PseBCHGI) in the process optimising coupled turnover with PseBC using deuterium wash in experiments, and establishing a method for co-factor regeneration in PseH tunover. Furthermore we establish conditions for purification of a soluble CMP-Pse5Ac7Ac synthetase enzyme PseF from Aeromonas caviae and utilise it in combination with the C. jejuni enzymes to achieve practical preparative synthesis of CMP-Pse5Ac7Ac in vitro, facilitating future biological studies.
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Affiliation(s)
- Harriet S Chidwick
- Department of Chemistry, University of York, Heslington Road, York, YO10 5DD, UK
| | - Emily K P Flack
- Department of Chemistry, University of York, Heslington Road, York, YO10 5DD, UK
| | - Tessa Keenan
- Department of Chemistry, University of York, Heslington Road, York, YO10 5DD, UK
| | - Julia Walton
- Department of Chemistry, University of York, Heslington Road, York, YO10 5DD, UK
| | - Gavin H Thomas
- Department of Biology, University of York, Heslington Road, York, YO10 5DD, UK
| | - Martin A Fascione
- Department of Chemistry, University of York, Heslington Road, York, YO10 5DD, UK.
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Ardissone S, Kint N, Viollier PH. Specificity in glycosylation of multiple flagellins by the modular and cell cycle regulated glycosyltransferase FlmG. eLife 2020; 9:e60488. [PMID: 33108275 PMCID: PMC7591256 DOI: 10.7554/elife.60488] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Accepted: 09/24/2020] [Indexed: 12/12/2022] Open
Abstract
How specificity is programmed into post-translational modification of proteins by glycosylation is poorly understood, especially for O-linked glycosylation systems. Here we reconstitute and dissect the substrate specificity underpinning the cytoplasmic O-glycosylation pathway that modifies all six flagellins, five structural and one regulatory paralog, in Caulobacter crescentus, a monopolarly flagellated alpha-proteobacterium. We characterize the biosynthetic pathway for the sialic acid-like sugar pseudaminic acid and show its requirement for flagellation, flagellin modification and efficient export. The cognate NeuB enzyme that condenses phosphoenolpyruvate with a hexose into pseudaminic acid is functionally interchangeable with other pseudaminic acid synthases. The previously unknown and cell cycle-regulated FlmG protein, a defining member of a new class of cytoplasmic O-glycosyltransferases, is required and sufficient for flagellin modification. The substrate specificity of FlmG is conferred by its N-terminal flagellin-binding domain. FlmG accumulates before the FlaF secretion chaperone, potentially timing flagellin modification, export, and assembly during the cell division cycle.
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Affiliation(s)
- Silvia Ardissone
- Department of Microbiology & Molecular Medicine, Faculty of Medicine / CMU, University of GenevaGenèveSwitzerland
| | - Nicolas Kint
- Department of Microbiology & Molecular Medicine, Faculty of Medicine / CMU, University of GenevaGenèveSwitzerland
| | - Patrick H Viollier
- Department of Microbiology & Molecular Medicine, Faculty of Medicine / CMU, University of GenevaGenèveSwitzerland
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Khairnar A, Sunsunwal S, Babu P, Ramya TNC. Novel serine/threonine-O-glycosylation with N-acetylneuraminic acid and 3-deoxy-D-manno-octulosonic acid by bacterial flagellin glycosyltransferases. Glycobiology 2020; 31:288-306. [PMID: 32886756 DOI: 10.1093/glycob/cwaa084] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 08/05/2020] [Accepted: 08/24/2020] [Indexed: 12/15/2022] Open
Abstract
Some bacterial flagellins are O-glycosylated on surface-exposed serine/threonine residues with nonulosonic acids such as pseudaminic acid, legionaminic acid and their derivatives by flagellin nonulosonic acid glycosyltransferases, also called motility-associated factors (Maf). We report here two new glycosidic linkages previously unknown in any organism, serine/threonine-O-linked N-acetylneuraminic acid (Ser/Thr-O-Neu5Ac) and serine/threonine-O-linked 3-deoxy-D-manno-octulosonic acid or keto-deoxyoctulosonate (Ser/Thr-O-KDO), both catalyzed by Geobacillus kaustophilus Maf and Clostridium botulinum Maf. We identified these novel glycosidic linkages in recombinant G. kaustophilus and C. botulinum flagellins that were coexpressed with their cognate recombinant Maf protein in Escherichia coli strains producing the appropriate nucleotide sugar glycosyl donor. Our finding that both G. kaustophilus Maf (putative flagellin sialyltransferase) and C. botulinum Maf (putative flagellin legionaminic acid transferase) catalyzed Neu5Ac and KDO transfer on to flagellin indicates that Maf glycosyltransferases display donor substrate promiscuity. Maf glycosyltransferases have the potential to radically expand the scope of neoglycopeptide synthesis and posttranslational protein engineering.
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Affiliation(s)
- Aasawari Khairnar
- Department of Protein Science and Engineering, CSIR-Institute of Microbial Technology, Sector 39-A, Chandigarh 160036, India
| | - Sonali Sunsunwal
- Department of Protein Science and Engineering, CSIR-Institute of Microbial Technology, Sector 39-A, Chandigarh 160036, India
| | - Ponnusamy Babu
- Glycomics and Glycoproteomics & Biologics Characterization Facility, Centre for Cellular and Molecular Platforms, National Centre for Biological Sciences-TIFR, Bengaluru, UAS-GKVK Campus, Bellary Road, 560065, India
| | - T N C Ramya
- Department of Protein Science and Engineering, CSIR-Institute of Microbial Technology, Sector 39-A, Chandigarh 160036, India
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10
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Small Noncoding RNA CjNC110 Influences Motility, Autoagglutination, AI-2 Localization, Hydrogen Peroxide Sensitivity, and Chicken Colonization in Campylobacter jejuni. Infect Immun 2020; 88:IAI.00245-20. [PMID: 32366573 DOI: 10.1128/iai.00245-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 04/22/2020] [Indexed: 12/21/2022] Open
Abstract
Small noncoding RNAs (ncRNAs) are involved in many important physiological functions in pathogenic microorganisms. Previous studies have identified the presence of noncoding RNAs in the major zoonotic pathogen Campylobacter jejuni; however, few have been functionally characterized to date. CjNC110 is a conserved ncRNA in C. jejuni, located downstream of the luxS gene, which is responsible for the production of the quorum sensing molecule autoinducer-2 (AI-2). In this study, we utilized strand specific high-throughput RNAseq to identify potential targets or interactive partners of CjNC110 in a sheep abortion clone of C. jejuni These data were then utilized to focus further phenotypic evaluation of the role of CjNC110 in motility, autoagglutination, quorum sensing, hydrogen peroxide sensitivity, and chicken colonization in C. jejuni Inactivation of the CjNC110 ncRNA led to a statistically significant decrease in autoagglutination ability as well as increased motility and hydrogen peroxide sensitivity compared to the wild-type. Extracellular AI-2 detection was decreased in ΔCjNC110; however, intracellular AI-2 accumulation was significantly increased, suggesting a key role of CjNC110 in modulating the transport of AI-2. Notably, ΔCjNC110 also showed a decreased ability to colonize chickens. Complementation of CjNC110 restored all phenotypic changes back to wild-type levels. The collective results of the phenotypic and transcriptomic changes observed in our data provide valuable insights into the pathobiology of C. jejuni sheep abortion clone and strongly suggest that CjNC110 plays an important role in the regulation of energy taxis, flagellar glycosylation, cellular communication via quorum sensing, oxidative stress tolerance, and chicken colonization in this important zoonotic pathogen.
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11
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Sacher JC, Shajahan A, Butcher J, Patry RT, Flint A, Hendrixson DR, Stintzi A, Azadi P, Szymanski CM. Binding of Phage-Encoded FlaGrab to Motile Campylobacter jejuni Flagella Inhibits Growth, Downregulates Energy Metabolism, and Requires Specific Flagellar Glycans. Front Microbiol 2020; 11:397. [PMID: 32265863 PMCID: PMC7099621 DOI: 10.3389/fmicb.2020.00397] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Accepted: 02/26/2020] [Indexed: 12/20/2022] Open
Abstract
Many bacterial pathogens display glycosylated surface structures that contribute to virulence, and targeting these structures is a viable strategy for pathogen control. The foodborne pathogen Campylobacter jejuni expresses a vast diversity of flagellar glycans, and flagellar glycosylation is essential for its virulence. Little is known about why C. jejuni encodes such a diverse set of flagellar glycans, but it has been hypothesized that evolutionary pressure from bacteriophages (phages) may have contributed to this diversity. However, interactions between Campylobacter phages and host flagellar glycans have not been characterized in detail. Previously, we observed that Gp047 (now renamed FlaGrab), a conserved Campylobacter phage protein, binds to C. jejuni flagella displaying the nine-carbon monosaccharide 7-acetamidino-pseudaminic acid, and that this binding partially inhibits cell growth. However, the mechanism of this growth inhibition, as well as how C. jejuni might resist this activity, are not well-understood. Here we use RNA-Seq to show that FlaGrab exposure leads C. jejuni 11168 cells to downregulate expression of energy metabolism genes, and that FlaGrab-induced growth inhibition is dependent on motile flagella. Our results are consistent with a model whereby FlaGrab binding transmits a signal through flagella that leads to retarded cell growth. To evaluate mechanisms of FlaGrab resistance in C. jejuni, we characterized the flagellar glycans and flagellar glycosylation loci of two C. jejuni strains naturally resistant to FlaGrab binding. Our results point toward flagellar glycan diversity as the mechanism of resistance to FlaGrab. Overall, we have further characterized the interaction between this phage-encoded flagellar glycan-binding protein and C. jejuni, both in terms of mechanism of action and mechanism of resistance. Our results suggest that C. jejuni encodes as-yet unidentified mechanisms for generating flagellar glycan diversity, and point to phage proteins as exciting lenses through which to study bacterial surface glycans.
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Affiliation(s)
- Jessica C Sacher
- Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada
| | - Asif Shajahan
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States
| | - James Butcher
- Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, ON, Canada
| | - Robert T Patry
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States.,Department of Microbiology, University of Georgia, Athens, GA, United States
| | - Annika Flint
- Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, ON, Canada
| | - David R Hendrixson
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Alain Stintzi
- Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, ON, Canada
| | - Parastoo Azadi
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States
| | - Christine M Szymanski
- Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada.,Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States.,Department of Microbiology, University of Georgia, Athens, GA, United States
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12
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Type III Secretion Effectors with Arginine N-Glycosyltransferase Activity. Microorganisms 2020; 8:microorganisms8030357. [PMID: 32131463 PMCID: PMC7142665 DOI: 10.3390/microorganisms8030357] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 02/27/2020] [Accepted: 02/29/2020] [Indexed: 01/31/2023] Open
Abstract
Type III secretion systems are used by many Gram-negative bacterial pathogens to inject proteins, known as effectors, into the cytosol of host cells. These virulence factors interfere with a diverse array of host signal transduction pathways and cellular processes. Many effectors have catalytic activities to promote post-translational modifications of host proteins. This review focuses on a family of effectors with glycosyltransferase activity that catalyze addition of N-acetyl-d-glucosamine to specific arginine residues in target proteins, leading to reduced NF-κB pathway activation and impaired host cell death. This family includes NleB from Citrobacter rodentium, NleB1 and NleB2 from enteropathogenic and enterohemorrhagic Escherichia coli, and SseK1, SseK2, and SseK3 from Salmonella enterica. First, we place these effectors in the general framework of the glycosyltransferase superfamily and in the particular context of the role of glycosylation in bacterial pathogenesis. Then, we provide detailed information about currently known members of this family, their role in virulence, and their targets.
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13
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Flack EKP, Chidwick HS, Best M, Thomas GH, Fascione MA. Synthetic Approaches for Accessing Pseudaminic Acid (Pse) Bacterial Glycans. Chembiochem 2020; 21:1397-1407. [PMID: 31944494 DOI: 10.1002/cbic.202000019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Indexed: 12/18/2022]
Abstract
Pseudaminic acids (Pses) are a group of non-mammalian nonulosonic acids (nulOs) that have been shown to be an important virulence factor for a number of pathogenic bacteria, including emerging multidrug-resistant ESKAPE pathogens. Despite their discovery over 30 years ago, relatively little is known about the biological significance of Pse glycans compared with their sialic acid analogues, primarily due to a lack of access to the synthetically challenging Pse architecture. Recently, however, the Pse backbone has been subjected to increasing synthetic exploration by carbohydrate (bio)chemists, and the total synthesis of complex Pse glycans achieved with inspiration from the biosynthesis and subsequent detailed study of chemical glycosylation by using Pse donors. Herein, context is provided for these efforts by summarising recent synthetic approaches pioneered for accessing Pse glycans, which are set to open up this underexplored area of glycoscience to the wider scientific community.
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Affiliation(s)
- Emily K P Flack
- Department of Chemistry, University of York, Heslington Road, Heslington, York, YO10 5DD, UK
| | - Harriet S Chidwick
- Department of Chemistry, University of York, Heslington Road, Heslington, York, YO10 5DD, UK
| | - Matthew Best
- Department of Chemistry, University of York, Heslington Road, Heslington, York, YO10 5DD, UK
| | - Gavin H Thomas
- Department of Biology, University of York, Heslington Road, Heslington, York, YO10 5DD, UK
| | - Martin A Fascione
- Department of Chemistry, University of York, Heslington Road, Heslington, York, YO10 5DD, UK
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14
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Chidwick HS, Fascione MA. Mechanistic and structural studies into the biosynthesis of the bacterial sugar pseudaminic acid (Pse5Ac7Ac). Org Biomol Chem 2020; 18:799-809. [PMID: 31913385 DOI: 10.1039/c9ob02433f] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The non-mammalian nonulosonic acid sugar pseudaminic acid (Pse) is present on the surface of a number of human pathogens including Campylobacter jejuni and Helicobacter pylori and other bacteria such as multidrug resistant Acinetobacter baumannii. It is likely important for evasion of the host immune sysyem, and also plays a role in bacterial motility through flagellin glycosylation. Herein we review the mechanistic and structural characterisation of the enzymes responsible for the biosynthesis of the Pse parent structure, Pse5Ac7Ac in bacteria.
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15
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Burnham PM, Hendrixson DR. Campylobacter jejuni: collective components promoting a successful enteric lifestyle. Nat Rev Microbiol 2019; 16:551-565. [PMID: 29892020 DOI: 10.1038/s41579-018-0037-9] [Citation(s) in RCA: 131] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Campylobacter jejuni is the leading cause of bacterial diarrhoeal disease in many areas of the world. The high incidence of sporadic cases of disease in humans is largely due to its prevalence as a zoonotic agent in animals, both in agriculture and in the wild. Compared with many other enteric bacterial pathogens, C. jejuni has strict growth and nutritional requirements and lacks many virulence and colonization determinants that are typically used by bacterial pathogens to infect hosts. Instead, C. jejuni has a different collection of factors and pathways not typically associated together in enteric pathogens to establish commensalism in many animal hosts and to promote diarrhoeal disease in the human population. In this Review, we discuss the cellular architecture and structure of C. jejuni, intraspecies genotypic variation, the multiple roles of the flagellum, specific nutritional and environmental growth requirements and how these factors contribute to in vivo growth in human and avian hosts, persistent colonization and pathogenesis of diarrhoeal disease.
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Affiliation(s)
- Peter M Burnham
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - David R Hendrixson
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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16
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Abstract
Sialic acids are cytoprotectors, mainly localized on the surface of cell membranes with multiple and outstanding cell biological functions. The history of their structural analysis, occurrence, and functions is fascinating and described in this review. Reports from different researchers on apparently similar substances from a variety of biological materials led to the identification of a 9-carbon monosaccharide, which in 1957 was designated "sialic acid." The most frequently occurring member of the sialic acid family is N-acetylneuraminic acid, followed by N-glycolylneuraminic acid and O-acetylated derivatives, and up to now over about 80 neuraminic acid derivatives have been described. They appeared first in the animal kingdom, ranging from echinoderms up to higher animals, in many microorganisms, and are also expressed in insects, but are absent in higher plants. Sialic acids are masks and ligands and play as such dual roles in biology. Their involvement in immunology and tumor biology, as well as in hereditary diseases, cannot be underestimated. N-Glycolylneuraminic acid is very special, as this sugar cannot be expressed by humans, but is a xenoantigen with pathogenetic potential. Sialidases (neuraminidases), which liberate sialic acids from cellular compounds, had been known from very early on from studies with influenza viruses. Sialyltransferases, which are responsible for the sialylation of glycans and elongation of polysialic acids, are studied because of their significance in development and, for instance, in cancer. As more information about the functions in health and disease is acquired, the use of sialic acids in the treatment of diseases is also envisaged.
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Affiliation(s)
- Roland Schauer
- Biochemisches Institut, Christian-Albrechts-Universität zu Kiel, Kiel, Germany.
| | - Johannis P Kamerling
- Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, The Netherlands.
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17
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Reimer JM, Harb I, Ovchinnikova OG, Jiang J, Whitfield C, Schmeing TM. Structural Insight into a Novel Formyltransferase and Evolution to a Nonribosomal Peptide Synthetase Tailoring Domain. ACS Chem Biol 2018; 13:3161-3172. [PMID: 30346688 DOI: 10.1021/acschembio.8b00739] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Nonribosomal peptide synthetases (NRPSs) increase the chemical diversity of their products by acquiring tailoring domains. Linear gramicidin synthetase starts with a tailoring formylation (F) domain, which likely originated from a sugar formyltransferase (FT) gene. Here, we present studies on an Anoxybacillus kamchatkensis sugar FT representative of the prehorizontal gene transfer FT. Gene cluster analysis reveals that this FT acts on a UDP-sugar in a novel pathway for synthesis of a 7-formamido derivative of CMP-pseudaminic acid. We recapitulate the pathway up to and including the formylation step in vitro, experimentally demonstrating the role of the FT. We also present X-ray crystal structures of the FT alone and with ligands, which unveil contrasts with other structurally characterized sugar FTs and show close structural similarity with the F domain. The structures reveal insights into the adaptations that were needed to co-opt and evolve a sugar FT into a functional and useful NRPS domain.
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Affiliation(s)
- Janice M. Reimer
- Department of Biochemistry, McGill University, Montréal, Québec H3G 0B1, Canada
| | - Ingrid Harb
- Department of Biochemistry, McGill University, Montréal, Québec H3G 0B1, Canada
| | - Olga G. Ovchinnikova
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Jessie Jiang
- Department of Biochemistry, McGill University, Montréal, Québec H3G 0B1, Canada
| | - Chris Whitfield
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - T. Martin Schmeing
- Department of Biochemistry, McGill University, Montréal, Québec H3G 0B1, Canada
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18
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van der Hooft JJJ, Alghefari W, Watson E, Everest P, Morton FR, Burgess KEV, Smith DGE. Unexpected differential metabolic responses of Campylobacter jejuni to the abundant presence of glutamate and fucose. Metabolomics 2018; 14:144. [PMID: 30830405 PMCID: PMC6208705 DOI: 10.1007/s11306-018-1438-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 10/04/2018] [Indexed: 02/01/2023]
Abstract
INTRODUCTION Campylobacter jejuni is the leading cause of foodborne bacterial enteritis in humans, and yet little is known in regard to how genetic diversity and metabolic capabilities among isolates affect their metabolic phenotype and pathogenicity. OBJECTIVES For instance, the C. jejuni 11168 strain can utilize both L-fucose and L-glutamate as a carbon source, which provides the strain with a competitive advantage in some environments and in this study we set out to assess the metabolic response of C. jejuni 11168 to the presence of L-fucose and L-glutamate in the growth medium. METHODS To achieve this, untargeted hydrophilic liquid chromatography coupled to mass spectrometry was used to obtain metabolite profiles of supernatant extracts obtained at three different time points up to 24 h. RESULTS This study identified both the depletion and the production and subsequent release of a multitude of expected and unexpected metabolites during the growth of C. jejuni 11168 under three different conditions. A large set of standards allowed identification of a number of metabolites. Further mass spectrometry fragmentation analysis allowed the additional annotation of substrate-specific metabolites. The results show that C. jejuni 11168 upon L-fucose addition indeed produces degradation products of the fucose pathway. Furthermore, methionine was faster depleted from the medium, consistent with previously-observed methionine auxotrophy. CONCLUSIONS Moreover, a multitude of not previously annotated metabolites in C. jejuni were found to be increased specifically upon L-fucose addition. These metabolites may well play a role in the pathogenicity of this C. jejuni strain.
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Affiliation(s)
| | - Wejdan Alghefari
- King Abdulaziz University, Jeddah, 21589, Kingdom of Saudi Arabia
- Institute of Biological Chemistry, Biophysics & Bioengineering, Heriot-Watt University, Edinburgh, EH14 4AS, UK
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, EH26 0PZ, UK
| | - Eleanor Watson
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, EH26 0PZ, UK
| | - Paul Everest
- School of Veterinary Medicine, University of Glasgow, Bearsden Road, Glasgow, G61 1QH, UK
| | - Fraser R Morton
- Glasgow Polyomics, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Karl E V Burgess
- Glasgow Polyomics, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, UK
| | - David G E Smith
- Institute of Biological Chemistry, Biophysics & Bioengineering, Heriot-Watt University, Edinburgh, EH14 4AS, UK.
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19
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Salah Ud-Din AIM, Roujeinikova A. Flagellin glycosylation with pseudaminic acid in Campylobacter and Helicobacter: prospects for development of novel therapeutics. Cell Mol Life Sci 2018; 75:1163-1178. [PMID: 29080090 PMCID: PMC11105201 DOI: 10.1007/s00018-017-2696-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 10/10/2017] [Accepted: 10/24/2017] [Indexed: 02/08/2023]
Abstract
Many pathogenic bacteria require flagella-mediated motility to colonise and persist in their hosts. Helicobacter pylori and Campylobacter jejuni are flagellated epsilonproteobacteria associated with several human pathologies, including gastritis, acute diarrhea, gastric carcinoma and neurological disorders. In both species, glycosylation of flagellin with an unusual sugar pseudaminic acid (Pse) plays a crucial role in the biosynthesis of functional flagella, and thereby in bacterial motility and pathogenesis. Pse is found only in pathogenic bacteria. Its biosynthesis via six consecutive enzymatic steps has been extensively studied in H. pylori and C. jejuni. This review highlights the importance of flagella glycosylation and details structural insights into the enzymes in the Pse pathway obtained via a combination of biochemical, crystallographic, and mutagenesis studies of the enzyme-substrate and -inhibitor complexes. It is anticipated that understanding the underlying structural and molecular basis of the catalytic mechanisms of the Pse-synthesising enzymes will pave the way for the development of novel antimicrobials.
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Affiliation(s)
- Abu Iftiaf Md Salah Ud-Din
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, VIC, Australia
| | - Anna Roujeinikova
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, VIC, Australia.
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia.
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20
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Sulzenbacher G, Roig-Zamboni V, Lebrun R, Guérardel Y, Murat D, Mansuelle P, Yamakawa N, Qian XX, Vincentelli R, Bourne Y, Wu LF, Alberto F. Glycosylate and move! The glycosyltransferase Maf is involved in bacterial flagella formation. Environ Microbiol 2017; 20:228-240. [DOI: 10.1111/1462-2920.13975] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 10/17/2017] [Accepted: 10/22/2017] [Indexed: 11/30/2022]
Affiliation(s)
| | | | - Régine Lebrun
- Plate-forme Protéomique; Institut de Microbiologie de la Méditerranée, FR3479 Aix-Marseille Université and Centre National de la Recherche Scientifique; Marseille 13402 France
| | - Yann Guérardel
- Unité de Glycobiologie Structurale et Fonctionnelle; UMR 8576 Université de Lille and Centre National de la Recherche Scientifique; Lille 59000 France
| | - Dorothée Murat
- Aix Marseille Univ, CNRS, LCB UMR7283; Marseille 13402 France
- International Associated Laboratory of Evolution and Development of Magnetotactic Organisms (LIA-MagMC); Centre National de la Recherche Scientifique; Marseille 13402 France
| | - Pascal Mansuelle
- Plate-forme Protéomique; Institut de Microbiologie de la Méditerranée, FR3479 Aix-Marseille Université and Centre National de la Recherche Scientifique; Marseille 13402 France
| | - Nao Yamakawa
- Unité de Glycobiologie Structurale et Fonctionnelle; UMR 8576 Université de Lille and Centre National de la Recherche Scientifique; Lille 59000 France
| | - Xin-Xin Qian
- Aix Marseille Univ, CNRS, LCB UMR7283; Marseille 13402 France
- International Associated Laboratory of Evolution and Development of Magnetotactic Organisms (LIA-MagMC); Centre National de la Recherche Scientifique; Marseille 13402 France
| | | | - Yves Bourne
- Aix Marseille Univ, CNRS, AFMB UMR7257; Marseille 13288 France
| | - Long-Fei Wu
- Aix Marseille Univ, CNRS, LCB UMR7283; Marseille 13402 France
- International Associated Laboratory of Evolution and Development of Magnetotactic Organisms (LIA-MagMC); Centre National de la Recherche Scientifique; Marseille 13402 France
| | - François Alberto
- Aix Marseille Univ, CNRS, LCB UMR7283; Marseille 13402 France
- International Associated Laboratory of Evolution and Development of Magnetotactic Organisms (LIA-MagMC); Centre National de la Recherche Scientifique; Marseille 13402 France
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21
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Pascoe B, Méric G, Yahara K, Wimalarathna H, Murray S, Hitchings MD, Sproston EL, Carrillo CD, Taboada EN, Cooper KK, Huynh S, Cody AJ, Jolley KA, Maiden MCJ, McCarthy ND, Didelot X, Parker CT, Sheppard SK. Local genes for local bacteria: Evidence of allopatry in the genomes of transatlantic Campylobacter populations. Mol Ecol 2017; 26:4497-4508. [PMID: 28493321 PMCID: PMC5600125 DOI: 10.1111/mec.14176] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 04/25/2017] [Accepted: 05/01/2017] [Indexed: 12/14/2022]
Abstract
The genetic structure of bacterial populations can be related to geographical locations of isolation. In some species, there is a strong correlation between geographical distance and genetic distance, which can be caused by different evolutionary mechanisms. Patterns of ancient admixture in Helicobacter pylori can be reconstructed in concordance with past human migration, whereas in Mycobacterium tuberculosis it is the lack of recombination that causes allopatric clusters. In Campylobacter, analyses of genomic data and molecular typing have been successful in determining the reservoir host species, but not geographical origin. We investigated biogeographical variation in highly recombining genes to determine the extent of clustering between genomes from geographically distinct Campylobacter populations. Whole‐genome sequences from 294 Campylobacter isolates from North America and the UK were analysed. Isolates from within the same country shared more recently recombined DNA than isolates from different countries. Using 15 UK/American closely matched pairs of isolates that shared ancestors, we identify regions that have frequently and recently recombined to test their correlation with geographical origin. The seven genes that demonstrated the greatest clustering by geography were used in an attribution model to infer geographical origin which was tested using a further 383 UK clinical isolates to detect signatures of recent foreign travel. Patient records indicated that in 46 cases, travel abroad had occurred <2 weeks prior to sampling, and genomic analysis identified that 34 (74%) of these isolates were of a non‐UK origin. Identification of biogeographical markers in Campylobacter genomes will contribute to improved source attribution of clinical Campylobacter infection and inform intervention strategies to reduce campylobacteriosis.
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Affiliation(s)
- Ben Pascoe
- The Milner Centre for Evolution, Department of Biology and Biochemistry, Bath University, Claverton Down, Bath, UK.,MRC CLIMB Consortium, Bath, UK
| | - Guillaume Méric
- The Milner Centre for Evolution, Department of Biology and Biochemistry, Bath University, Claverton Down, Bath, UK
| | - Koji Yahara
- Department of Bacteriology II, National Institute of Infectious Diseases, Tokyo, Japan.,Swansea University Medical School, Swansea University, Swansea, UK
| | | | - Susan Murray
- Swansea University Medical School, Swansea University, Swansea, UK
| | | | - Emma L Sproston
- Bureau of Microbial Hazards, Health Canada, Ottawa, ON, Canada
| | | | - Eduardo N Taboada
- National Microbiology Laboratory at Lethbridge, Public Health Agency of Canada, Lethbridge, AB, Canada
| | - Kerry K Cooper
- Department of Biology, California State University Northridge, Northridge, CA, USA
| | - Steven Huynh
- Produce Safety and Microbiology Research Unit, Agricultural Research Service, US Department of Agriculture, Albany, CA, USA
| | - Alison J Cody
- Department of Zoology, University of Oxford, Oxford, UK
| | | | - Martin C J Maiden
- Department of Zoology, University of Oxford, Oxford, UK.,NIHR Health Protection Research Unit in Gastrointestinal Infections, Oxford, UK
| | - Noel D McCarthy
- Department of Zoology, University of Oxford, Oxford, UK.,NIHR Health Protection Research Unit in Gastrointestinal Infections, Oxford, UK.,University of Warwick, Coventry, UK
| | - Xavier Didelot
- Department of Infectious Disease Epidemiology, Imperial College London, London, UK
| | - Craig T Parker
- Produce Safety and Microbiology Research Unit, Agricultural Research Service, US Department of Agriculture, Albany, CA, USA
| | - Samuel K Sheppard
- The Milner Centre for Evolution, Department of Biology and Biochemistry, Bath University, Claverton Down, Bath, UK.,MRC CLIMB Consortium, Bath, UK.,Department of Zoology, University of Oxford, Oxford, UK
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22
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Kao CY, Chen JW, Wang S, Sheu BS, Wu JJ. The Helicobacter pylori J99 jhp0106 Gene, under the Control of the CsrA/RpoN Regulatory System, Modulates Flagella Formation and Motility. Front Microbiol 2017; 8:483. [PMID: 28400753 PMCID: PMC5368276 DOI: 10.3389/fmicb.2017.00483] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 03/08/2017] [Indexed: 12/11/2022] Open
Abstract
CsrA has been shown to positively control the expression of flagella-related genes, including flaA and flaB, through regulating expression of an alternative sigma factor RpoN in Helicobacter pylori J99. Here, we aimed to characterize the CsrA regulatory system by comparative transcriptomic analysis carried out with RNA-seq on strain J99 and a csrA mutant. Fifty-three genes in the csrA mutant were found to be differentially expressed compared with the wild-type. Among CsrA-regulated genes, jhp0106, with unclear function, was found located downstream of flaB in the J99 genome. We hypothesized that flaB-jhp0106 is in an operon under the control of RpoN binding to the flaB promoter. The RT-qPCR results showed the expression of jhp0106 was decreased 76 and 92% in the csrA and rpoN mutants, respectively, compared to the wild-type. Moreover, mutations of the RpoN binding site in the flaB promoter region resulted in decreased expression of flaB and jhp0106 and deficient motility. Three-dimensional structure modeling results suggested that Jhp0106 was a glycosyltransferase. The role of jhp0106 in H. pylori was further investigated by constructing the jhp0106 mutant and revertant strains. A soft-agar motility assay and transmission electron microscope were used to determine the motility and flagellar structure of examined strains, and the results showed the loss of motility and flagellar structure in jhp0106 mutant J99. In conclusion, we found jhp0106, under the control of the CsrA/RpoN regulatory system, plays a critical role in H. pylori flagella formation.
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Affiliation(s)
- Cheng-Yen Kao
- Department of Biotechnology and Laboratory Science in Medicine, School of Biomedical Science and Engineering, National Yang Ming University Taipei, Taiwan
| | - Jenn-Wei Chen
- Center of Infectious Disease and Signaling Research, National Cheng Kung UniversityTainan, Taiwan; Department of Microbiology and Immunology, College of Medicine, National Cheng Kung UniversityTainan, Taiwan
| | - Shuying Wang
- Center of Infectious Disease and Signaling Research, National Cheng Kung UniversityTainan, Taiwan; Department of Microbiology and Immunology, College of Medicine, National Cheng Kung UniversityTainan, Taiwan
| | - Bor-Shyang Sheu
- Department of Internal Medicine, College of Medicine, National Cheng Kung University Hospital, National Cheng Kung UniversityTainan, Taiwan; Department of Internal Medicine, Tainan Hospital, Ministry of Health & WelfareTainan, Taiwan
| | - Jiunn-Jong Wu
- Department of Biotechnology and Laboratory Science in Medicine, School of Biomedical Science and Engineering, National Yang Ming University Taipei, Taiwan
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23
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O’Kane PM, Connerton IF. Characterisation of Aerotolerant Forms of a Robust Chicken Colonizing Campylobacter coli. Front Microbiol 2017; 8:513. [PMID: 28396658 PMCID: PMC5366326 DOI: 10.3389/fmicb.2017.00513] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Accepted: 03/13/2017] [Indexed: 12/22/2022] Open
Abstract
Campylobacter contaminated poultry meat is a major source of human foodborne illness. Campylobacter coli strain OR12 is a robust colonizer of chickens that was previously shown to outcompete and displace other Campylobacter strains from the chicken's gastrointestinal tract. This strain is capable of aerobic growth on blood agar. Serial aerobic passage increased this aerotolerance as assessed by quantitative assays for growth and survival on solid media. Aerotolerance was also associated with increased peroxide stress resistance. Aerobic passage did not alter cellular morphology or motility or hinder the microaerobic growth rate. Colonization of broiler chickens by aerotolerant C. coli OR12 was significantly lower than the wild-type strain at 3 days after challenge but not by 7 days, suggesting adaptation had occurred. Bacteria recovered from chickens had retained their aerotolerance, indicating this trait is stable. Whole genome sequencing enabled comparison with the wild-type sequence. Twenty-three point mutations were present, none of which were in genes known to affect oxidative stress resistance. Insertions or deletions caused frame shifts in several genes including, phosphoglycerate kinase and the b subunit of pyruvate carboxylase that suggest modification of central and carbohydrate metabolism in response to aerobic growth. Other genes affected include those encoding putative carbonic anhydrase, motility accessory factor, filamentous haemagglutinin, and aminoacyl dipeptidase proteins. Aerotolerance has the potential to affect environmental success and survival. Increased environmental survival outside of the host intestinal tract may allow opportunities for transmission between hosts. Resistance to oxidative stress may equate to increased virulence by virtue of reduced susceptibility to oxidative free radicals produced by host immune responses. Finally, resistance to ambient atmospheric oxygen may allow increased survival on chicken skin, and therefore constitutes an increased risk to public health.
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Affiliation(s)
| | - Ian F. Connerton
- Division of Food Sciences, School of Biosciences, University of NottinghamSutton Bonington, UK
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Analysis of Campylobacter jejuni infection in the gnotobiotic piglet and genome-wide identification of bacterial factors required for infection. Sci Rep 2017; 7:44283. [PMID: 28281647 PMCID: PMC5345035 DOI: 10.1038/srep44283] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 02/06/2017] [Indexed: 12/30/2022] Open
Abstract
To investigate how Campylobacter jejuni causes the clinical symptoms of diarrhoeal disease in humans, use of a relevant animal model is essential. Such a model should mimic the human disease closely in terms of host physiology, incubation period before onset of disease, clinical signs and a comparable outcome of disease. In this study, we used a gnotobiotic piglet model to study determinants of pathogenicity of C. jejuni. In this model, C. jejuni successfully established infection and piglets developed an increased temperature with watery diarrhoea, which was caused by a leaky epithelium and reduced bile re-absorption in the intestines. Further, we assessed the C. jejuni genes required for infection of the porcine gastrointestinal tract utilising a transposon (Tn) mutant library screen. A total of 123 genes of which Tn mutants showed attenuated piglet infection were identified. Our screen highlighted a crucial role for motility and chemotaxis, as well as central metabolism. In addition, Tn mutants of 14 genes displayed enhanced piglet infection. This study gives a unique insight into the mechanisms of C. jejuni disease in terms of host physiology and contributing bacterial factors.
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Kurniyati K, Kelly JF, Vinogradov E, Robotham A, Tu Y, Wang J, Liu J, Logan SM, Li C. A novel glycan modifies the flagellar filament proteins of the oral bacterium Treponema denticola. Mol Microbiol 2016; 103:67-85. [PMID: 27696564 DOI: 10.1111/mmi.13544] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/27/2016] [Indexed: 01/12/2023]
Abstract
While protein glycosylation has been reported in several spirochetes including the syphilis bacterium Treponema pallidum and Lyme disease pathogen Borrelia burgdorferi, the pertinent glycan structures and their roles remain uncharacterized. Herein, a novel glycan with an unusual chemical composition and structure in the oral spirochete Treponema denticola, a keystone pathogen of periodontitis was reported. The identified glycan of mass 450.2 Da is composed of a monoacetylated nonulosonic acid (Non) with a novel extended N7 acyl modification, a 2-methoxy-4,5,6-trihydroxy-hexanoyl residue in which the Non has a pseudaminic acid configuration (L-glycero-L-manno) and is β-linked to serine or threonine residues. This novel glycan modifies the flagellin proteins (FlaBs) of T. denticola by O-linkage at multiple sites near the D1 domain, a highly conserved region of bacterial flagellins that interact with Toll-like receptor 5. Furthermore, mutagenesis studies demonstrate that the glycosylation plays an essential role in the flagellar assembly and motility of T. denticola. To our knowledge, this novel glycan and its unique modification sites have not been reported previously in any bacteria.
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Affiliation(s)
- Kurni Kurniyati
- Department of Oral Biology, The State University of New York at Buffalo, New York, NY, 14214, USA
| | - John F Kelly
- Vaccine Program, Human Health Therapeutics, National Research Council, Ottawa, Ontario, K1A 0R6, Canada
| | - Evgeny Vinogradov
- Vaccine Program, Human Health Therapeutics, National Research Council, Ottawa, Ontario, K1A 0R6, Canada
| | - Anna Robotham
- Vaccine Program, Human Health Therapeutics, National Research Council, Ottawa, Ontario, K1A 0R6, Canada
| | - Youbing Tu
- Department of Oral Biology, The State University of New York at Buffalo, New York, NY, 14214, USA
| | - Juyu Wang
- Department of Pathology and Laboratory Medicine, McGovern Medical School at UT Health Science Center, Houston, TX, 77030, USA
| | - Jun Liu
- Department of Pathology and Laboratory Medicine, McGovern Medical School at UT Health Science Center, Houston, TX, 77030, USA
| | - Susan M Logan
- Vaccine Program, Human Health Therapeutics, National Research Council, Ottawa, Ontario, K1A 0R6, Canada
| | - Chunhao Li
- Department of Oral Biology, The State University of New York at Buffalo, New York, NY, 14214, USA.,Department of Microbiology and Immunology, The State University of New York at Buffalo, New York, NY, 14214, USA
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Li H, Debowski AW, Liao T, Tang H, Nilsson HO, Marshall BJ, Stubbs KA, Benghezal M. Understanding protein glycosylation pathways in bacteria. Future Microbiol 2016; 12:59-72. [PMID: 27689684 DOI: 10.2217/fmb-2016-0166] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Through advances in analytical methods to detect glycoproteins and to determine glycan structures, there have been increasing reports of protein glycosylation in bacteria. In this review, we summarize the known pathways for bacterial protein glycosylation: lipid carrier-mediated 'en bloc' glycosylation; and cytoplasmic stepwise protein glycosylation. The exploitation of bacterial protein glycosylation systems, especially the 'mix and match' of three independent but similar pathways (oligosaccharyltransferase-mediated protein glycosylation, lipopolysaccharide and peptidoglycan biosynthesis) in Gram-negative bacteria for glycoengineering recombinant glycoproteins is also discussed.
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Affiliation(s)
- Hong Li
- West China Marshall Research Centre for Infectious Diseases, Centre of Infectious Diseases, West China Hospital of Sichuan University, Chengdu 610041, China.,Helicobacter Pylori Research Laboratory, School of Pathology & Laboratory Medicine, Marshall Centre for Infectious Disease Research & Training, The University of Western Australia, M504, L Block, QEII Medical Centre, Nedlands, WA 6009, Australia
| | - Aleksandra W Debowski
- Helicobacter Pylori Research Laboratory, School of Pathology & Laboratory Medicine, Marshall Centre for Infectious Disease Research & Training, The University of Western Australia, M504, L Block, QEII Medical Centre, Nedlands, WA 6009, Australia.,School of Chemistry & Biochemistry, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Tingting Liao
- Helicobacter Pylori Research Laboratory, School of Pathology & Laboratory Medicine, Marshall Centre for Infectious Disease Research & Training, The University of Western Australia, M504, L Block, QEII Medical Centre, Nedlands, WA 6009, Australia
| | - Hong Tang
- West China Marshall Research Centre for Infectious Diseases, Centre of Infectious Diseases, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Hans-Olof Nilsson
- Ondek Pty Ltd, School of Pathology & Laboratory Medicine, Marshall Centre for Infectious Disease Research & Training, The University of Western Australia, M504, L Block, QEII Medical Centre, Nedlands, WA 6009, Australia
| | - Barry J Marshall
- Helicobacter Pylori Research Laboratory, School of Pathology & Laboratory Medicine, Marshall Centre for Infectious Disease Research & Training, The University of Western Australia, M504, L Block, QEII Medical Centre, Nedlands, WA 6009, Australia
| | - Keith A Stubbs
- School of Chemistry & Biochemistry, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Mohammed Benghezal
- Helicobacter Pylori Research Laboratory, School of Pathology & Laboratory Medicine, Marshall Centre for Infectious Disease Research & Training, The University of Western Australia, M504, L Block, QEII Medical Centre, Nedlands, WA 6009, Australia.,Swiss Vitamin Institute, Route de la Corniche 1, CH-1066 Epalinges, Switzerland
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Schäffer C, Messner P. Emerging facets of prokaryotic glycosylation. FEMS Microbiol Rev 2016; 41:49-91. [PMID: 27566466 DOI: 10.1093/femsre/fuw036] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 02/17/2016] [Accepted: 08/01/2016] [Indexed: 12/16/2022] Open
Abstract
Glycosylation of proteins is one of the most prevalent post-translational modifications occurring in nature, with a wide repertoire of biological implications. Pathways for the main types of this modification, the N- and O-glycosylation, can be found in all three domains of life-the Eukarya, Bacteria and Archaea-thereby following common principles, which are valid also for lipopolysaccharides, lipooligosaccharides and glycopolymers. Thus, studies on any glycoconjugate can unravel novel facets of the still incompletely understood fundamentals of protein N- and O-glycosylation. While it is estimated that more than two-thirds of all eukaryotic proteins would be glycosylated, no such estimate is available for prokaryotic glycoproteins, whose understanding is lagging behind, mainly due to the enormous variability of their glycan structures and variations in the underlying glycosylation processes. Combining glycan structural information with bioinformatic, genetic, biochemical and enzymatic data has opened up an avenue for in-depth analyses of glycosylation processes as a basis for glycoengineering endeavours. Here, the common themes of glycosylation are conceptualised for the major classes of prokaryotic (i.e. bacterial and archaeal) glycoconjugates, with a special focus on glycosylated cell-surface proteins. We describe the current knowledge of biosynthesis and importance of these glycoconjugates in selected pathogenic and beneficial microbes.
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Affiliation(s)
- Christina Schäffer
- Department of NanoBiotechnology, Institute of Biologically Inspired Materials, NanoGlycobiology unit, Universität für Bodenkultur Wien, A-1180 Vienna, Austria
| | - Paul Messner
- Department of NanoBiotechnology, Institute of Biologically Inspired Materials, NanoGlycobiology unit, Universität für Bodenkultur Wien, A-1180 Vienna, Austria
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Rossi FA, Medeot DB, Liaudat JP, Pistorio M, Jofré E. In Azospirillum brasilense, mutations in flmA or flmB genes affect polar flagellum assembly, surface polysaccharides, and attachment to maize roots. Microbiol Res 2016; 190:55-62. [PMID: 27393999 DOI: 10.1016/j.micres.2016.05.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 04/02/2016] [Accepted: 05/13/2016] [Indexed: 11/28/2022]
Abstract
Azospirillum brasilense is a soil bacterium capable of promoting plant growth. Several surface components were previously reported to be involved in the attachment of A. brasilense to root plants. Among these components are the exopolysaccharide (EPS), lipopolysaccharide (LPS) and the polar flagellum. Flagellin from polar flagellum is glycosylated and it was suggested that genes involved in such a posttranslational modification are the same ones involved in the biosynthesis of sugars present in the O-antigen of the LPS. In this work, we report on the characterization of two homologs present in A. brasilense Cd, to the well characterized flagellin modification genes, flmA and flmB, from Aeromonas caviae. We show that mutations in either flmA or flmB genes of A. brasilense resulted in non-motile cells due to alterations in the polar flagellum assembly. Moreover, these mutations also affected the capability of A. brasilense cells to adsorb to maize roots and to produce LPS and EPS. By generating a mutant containing the polar flagellum affected in their rotation, we show the importance of the bacterial motility for the early colonization of maize roots.
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Affiliation(s)
- Fernando Ariel Rossi
- Departmento de Ciencias Naturales, Facultad de Ciencias Exactas Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional 36 Km 601, 5800 Río Cuarto, Argentina
| | - Daniela Beatriz Medeot
- Departmento de Biología Molecular, Facultad de Ciencias Exactas Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional 36 Km 601, 5800 Río Cuarto, Argentina
| | - Juan Pablo Liaudat
- Departmento de Ciencias Naturales, Facultad de Ciencias Exactas Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional 36 Km 601, 5800 Río Cuarto, Argentina
| | - Mariano Pistorio
- IBBM (Instituto de Biotecnología y Biología Molecular), CCT-La Plata CONICET-, Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calles 47 y 115, 1900 La Plata, Argentina
| | - Edgardo Jofré
- Departmento de Ciencias Naturales, Facultad de Ciencias Exactas Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional 36 Km 601, 5800 Río Cuarto, Argentina.
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Identifying Potential Mechanisms Enabling Acidophily in the Ammonia-Oxidizing Archaeon "Candidatus Nitrosotalea devanaterra". Appl Environ Microbiol 2016; 82:2608-2619. [PMID: 26896134 PMCID: PMC4836417 DOI: 10.1128/aem.04031-15] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 02/13/2016] [Indexed: 01/11/2023] Open
Abstract
Ammonia oxidation is the first and rate-limiting step in nitrification and is dominated by two distinct groups of microorganisms in soil: ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB). AOA are often more abundant than AOB and dominate activity in acid soils. The mechanism of ammonia oxidation under acidic conditions has been a long-standing paradox. While high rates of ammonia oxidation are frequently measured in acid soils, cultivated ammonia oxidizers grew only at near-neutral pH when grown in standard laboratory culture. Although a number of mechanisms have been demonstrated to enable neutrophilic AOB growth at low pH in the laboratory, these have not been demonstrated in soil, and the recent cultivation of the obligately acidophilic ammonia oxidizer “Candidatus Nitrosotalea devanaterra” provides a more parsimonious explanation for the observed high rates of activity. Analysis of the sequenced genome, transcriptional activity, and lipid content of “Ca. Nitrosotalea devanaterra” reveals that previously proposed mechanisms used by AOB for growth at low pH are not essential for archaeal ammonia oxidation in acidic environments. Instead, the genome indicates that “Ca. Nitrosotalea devanaterra” contains genes encoding both a predicted high-affinity substrate acquisition system and potential pH homeostasis mechanisms absent in neutrophilic AOA. Analysis of mRNA revealed that candidate genes encoding the proposed homeostasis mechanisms were all expressed during acidophilic growth, and lipid profiling by high-performance liquid chromatography–mass spectrometry (HPLC-MS) demonstrated that the membrane lipids of “Ca. Nitrosotalea devanaterra” were not dominated by crenarchaeol, as found in neutrophilic AOA. This study for the first time describes a genome of an obligately acidophilic ammonia oxidizer and identifies potential mechanisms enabling this unique phenotype for future biochemical characterization.
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Williams JT, Corcilius L, Kiefel MJ, Payne RJ. Total Synthesis of Native 5,7-Diacetylpseudaminic Acid from N-Acetylneuraminic Acid. J Org Chem 2016; 81:2607-11. [PMID: 26907566 DOI: 10.1021/acs.joc.5b02754] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The pseudaminic acids are a family of 5,7-diamino-3,5,7,9-tetradeoxynonulosonic acids that are functional components of flagellin and pili proteins within clinically relevant Gram-negative bacteria. Herein, we describe the total synthesis of the most common pseudaminic acid, 5,7-diacetylpseudaminic acid, from N-acetylneuraminic acid. The divergent nature of the route reported here provides a robust and versatile means to access other members of the family, together with analogues, for probing the functional role of the pseudaminic acids and pseudaminic acid derived proteins in the future.
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Affiliation(s)
- James T Williams
- School of Chemistry, The University of Sydney , Sydney, NSW, 2006, Australia
| | - Leo Corcilius
- School of Chemistry, The University of Sydney , Sydney, NSW, 2006, Australia
| | - Milton J Kiefel
- Institute for Glycomics, Griffith University Gold Coast Campus , Southport, QLD, 4222, Australia
| | - Richard J Payne
- School of Chemistry, The University of Sydney , Sydney, NSW, 2006, Australia
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Abstract
Metabolomics is an analytical toolbox to describe (all) low-molecular-weight compounds in a biological system, as cells, tissues, urine, and feces, as well as in serum and plasma. To analyze such complex biological samples, high requirements on the analytical technique are needed due to the high variation in compound physico-chemistry (cholesterol derivatives, amino acids, fatty acids as SCFA, MCFA, or LCFA, or pathway-related metabolites belonging to each individual organism) and concentration dynamic range. All main separation techniques (LC-MS, GC-MS) are applied in routine to metabolomics hyphenated or not to mass spectrometry, and capillary electrophoresis is a powerful high-resolving technique but still underused in this field of complex samples. Metabolomics can be performed in the non-targeted way to gain an overview on metabolite profiles in biological samples. Targeted metabolomics is applied to analyze quantitatively pre-selected metabolites. This chapter reviews the use of capillary electrophoresis in the field of metabolomics and exemplifies solutions in metabolite profiling and analysis in urine and plasma.
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Zebian N, Merkx-Jacques A, Pittock PP, Houle S, Dozois CM, Lajoie GA, Creuzenet C. Comprehensive analysis of flagellin glycosylation in Campylobacter jejuni NCTC 11168 reveals incorporation of legionaminic acid and its importance for host colonization. Glycobiology 2015; 26:386-97. [PMID: 26582606 DOI: 10.1093/glycob/cwv104] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 11/03/2015] [Indexed: 12/26/2022] Open
Abstract
Campylobacter jejuni is the leading cause of bacterial gastroenteritis. It relies on several virulence factors for host colonization, including glycosylated flagella. C. jejuni NCTC 11168 modifies its flagellins with pseudaminic acid derivatives. It is also presumed to modify these proteins with legionaminic acid, although no glycopeptide evidence was available at the onset of this study. The enzyme encoded by cj1319 can be used to make legionaminic acid in vitro, but the pathway for legionaminic acid synthesis partially inferred by knockout mutagenesis in Campylobacter coli VC167 excludes Cj1319. To address this contradiction, we examined the presence of legionaminic acid in flagellin glycopeptides of wild-type (WT) C. jejuni NCTC 11168 and of a cj1319 knockout mutant. We used high-energy collision-induced dissociation to obtain amino acid sequences while also visualizing signature sugar oxonium ions. Data analysis was performed with PEAKS software, and spectra were manually inspected for glycopeptide determination and verification. We showed that legionaminic acid is present on the flagellins of C. jejuni NCTC 11168 and that flagellin glycosylation is highly heterogeneous, with up to six different sugars singly present at a given site. We found that the cj1319 mutant produces more legionaminic acid than WT, thus excluding the requirement for Cj1319 for legionaminic acid synthesis. We also showed that this mutant has enhanced chicken colonization compared with WT, which may in part be attributed to the high content of legionaminic acid on its flagella.
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Affiliation(s)
| | | | - Paula P Pittock
- Department of Biochemistry, Western University, London, ON N6A 5C1, Canada
| | | | | | - Gilles A Lajoie
- Department of Biochemistry, Western University, London, ON N6A 5C1, Canada
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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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High-Frequency Variation of Purine Biosynthesis Genes Is a Mechanism of Success in Campylobacter jejuni. mBio 2015; 6:e00612-15. [PMID: 26419875 PMCID: PMC4611032 DOI: 10.1128/mbio.00612-15] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
UNLABELLED Phenotypic variation is prevalent in the zoonotic pathogen Campylobacter jejuni, the leading agent of enterocolitis in the developed world. Heterogeneity enhances the survival and adaptive malleability of bacterial populations because variable phenotypes may allow some cells to be protected against future stress. Exposure to hyperosmotic stress previously revealed prevalent differences in growth between C. jejuni strain 81-176 colonies due to resistant or sensitive phenotypes, and these isolated colonies continued to produce progeny with differential phenotypes. In this study, whole-genome sequencing of isolated colonies identified allelic variants of two purine biosynthesis genes, purF and apt, encoding phosphoribosyltransferases that utilize a shared substrate. Genetic analyses determined that purF was essential for fitness, while apt was critical. Traditional and high-depth amplicon-sequencing analyses confirmed extensive intrapopulation genetic variation of purF and apt that resulted in viable strains bearing alleles with in-frame insertion duplications, deletions, or missense polymorphisms. Different purF and apt alleles were associated with various stress survival capabilities under several niche-relevant conditions and contributed to differential intracellular survival in an epithelial cell infection model. Amplicon sequencing revealed that intracellular survival selected for stress-fit purF and apt alleles, as did exposure to oxygen and hyperosmotic stress. Putative protein recognition direct repeat sequences were identified in purF and apt, and a DNA-protein affinity screen captured a predicted exonuclease that promoted the global spontaneous mutation rate. This work illustrates the adaptive properties of high-frequency genetic variation in two housekeeping genes, which influences C. jejuni survival under stress and promotes its success as a pathogen. IMPORTANCE C. jejuni is an important cause of bacterial diarrheal illness. Bacterial populations have many strategies for stress survival, but phenotypic variation due to genetic diversity has a powerful advantage: no matter how swift the change in environment, a fraction of the population already expresses the survival trait. Nonclonality is thus increasingly viewed as a mechanism of population success. Our previous work identified prominent resistant/sensitive colonial variation in C. jejuni bacteria in response to hyperosmotic stress; in the work presented here, we attribute that to high-frequency genetic variation in two purine biosynthesis genes, purF and apt. We demonstrated selective pressure for nonlethal mutant alleles of both genes, showed that single-cell variants had the capacity to give rise to diverse purF and apt populations, and determined that stress exposure selected for desirable alleles. Thus, a novel C. jejuni adaptive strategy was identified, which was, unusually, reliant on prevalent genetic variation in two housekeeping genes.
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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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Wu Z, Sahin O, Shen Z, Liu P, Miller WG, Zhang Q. Multi-omics approaches to deciphering a hypervirulent strain of Campylobacter jejuni. Genome Biol Evol 2014; 5:2217-30. [PMID: 24201373 PMCID: PMC3845652 DOI: 10.1093/gbe/evt172] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Campylobacter jejuni clone SA recently emerged as the predominant cause of sheep abortion in the United States and is also associated with foodborne gastroenteritis in humans. A distinct phenotype of this clone is its ability to induce bacteremia and abortion. To facilitate understanding the pathogenesis of this hypervirulent clone, we analyzed a clinical isolate (IA3902) of clone SA using multi-omics approaches. The genome of IA3902 contains a circular chromosome of 1,635,045 bp and a circular plasmid of 37,174 bp. Comparative genomic analysis revealed that IA3902 is most closely related to C. jejuni NCTC11168, which is a reference strain and was previously shown to be non-abortifacient in pregnant animals. Despite the high genomic synteny and sequence homology, there are 12 variable regions (VRs) and 8,696 single-nucleotide polymorphisms and indels between the two genomes. Notably, the variable genes in the capsular polysaccharides biosynthesis and O-linked glycosylation loci of IA3902 are highly homogenous to their counterparts in C. jejuni subsp. doylei and C. jejuni G1, which are known to be frequently associated with bacteremia. Transcriptomic and proteomic profiles were conducted to compare IA3902 with NCTC11168, which revealed that the pathways of energy generation, motility, and serine utilization were significantly up-regulated in IA3902, whereas the pathways of iron uptake and proline, glutamate, aspartate, and lactate utilization were significantly down-regulated. These results suggest that C. jejuni clone SA has evolved distinct genomic content and gene expression patterns that modulate surface polysacharide structures, motilitiy, and metabolic pathways. These changes may have contributed to its hyper-virulence in abortion induction.
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Affiliation(s)
- Zuowei Wu
- Department of Veterinary Microbiology and Preventive Medicine, Iowa State University
| | - Orhan Sahin
- Department of Veterinary Microbiology and Preventive Medicine, Iowa State University
| | - Zhangqi Shen
- Department of Veterinary Microbiology and Preventive Medicine, Iowa State University
| | - Peng Liu
- Department of Statistics, Iowa State University
| | - William G. Miller
- U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA
| | - Qijing Zhang
- Department of Veterinary Microbiology and Preventive Medicine, Iowa State University
- *Corresponding author: E-mail:
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Small-molecule inhibitors of the pseudaminic acid biosynthetic pathway: targeting motility as a key bacterial virulence factor. Antimicrob Agents Chemother 2014; 58:7430-40. [PMID: 25267679 DOI: 10.1128/aac.03858-14] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Helicobacter pylori is motile by means of polar flagella, and this motility has been shown to play a critical role in pathogenicity. The major structural flagellin proteins have been shown to be glycosylated with the nonulosonate sugar, pseudaminic acid (Pse). This glycan is unique to microorganisms, and the process of flagellin glycosylation is required for H. pylori flagellar assembly and consequent motility. As such, the Pse biosynthetic pathway offers considerable potential as an antivirulence drug target, especially since motility is required for H. pylori colonization and persistence in the host. This report describes screening the five Pse biosynthetic enzymes for small-molecule inhibitors using both high-throughput screening (HTS) and in silico (virtual screening [VS]) approaches. Using a 100,000-compound library, 1,773 hits that exhibited a 40% threshold inhibition at a 10 μM concentration were identified by HTS. In addition, VS efforts using a 1.6-million compound library directed at two pathway enzymes identified 80 hits, 4 of which exhibited reasonable inhibition at a 10 μM concentration in vitro. Further secondary screening which identified 320 unique molecular structures or validated hits was performed. Following kinetic studies and structure-activity relationship (SAR) analysis of selected inhibitors from our refined list of 320 compounds, we demonstrated that three inhibitors with 50% inhibitory concentrations (IC50s) of approximately 14 μM, which belonged to a distinct chemical cluster, were able to penetrate the Gram-negative cell membrane and prevent formation of flagella.
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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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Parker JL, Lowry RC, Couto NAS, Wright PC, Stafford GP, Shaw JG. Maf-dependent bacterial flagellin glycosylation occurs before chaperone binding and flagellar T3SS export. Mol Microbiol 2014; 92:258-72. [PMID: 24527847 PMCID: PMC4065374 DOI: 10.1111/mmi.12549] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/11/2014] [Indexed: 02/06/2023]
Abstract
Bacterial swimming is mediated by rotation of a filament that is assembled via polymerization of flagellin monomers after secretion via a dedicated flagellar Type III secretion system. Several bacteria decorate their flagellin with sialic acid related sugars that is essential for motility. Aeromonas caviae is a model organism for this process as it contains a genetically simple glycosylation system and decorates its flagellin with pseudaminic acid (Pse). The link between flagellin glycosylation and export has yet to be fully determined. We examined the role of glycosylation in the export and assembly process in a strain lacking Maf1, a protein involved in the transfer of Pse onto flagellin at the later stages of the glycosylation pathway. Immunoblotting, established that glycosylation is not required for flagellin export but is essential for filament assembly since non-glycosylated flagellin is still secreted. Maf1 interacts directly with its flagellin substrate in vivo, even in the absence of pseudaminic acid. Flagellin glycosylation in a flagellin chaperone mutant (flaJ) indicated that glycosylation occurs in the cytoplasm before chaperone binding and protein secretion. Preferential chaperone binding to glycosylated flagellin revealed its crucial role, indicating that this system has evolved to favour secretion of the polymerization competent glycosylated form.
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Affiliation(s)
- Jennifer L Parker
- Department of Infection and Immunity, University of Sheffield, Sheffield, S10 2RX, UK
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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
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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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Zunk M, Kiefel MJ. The occurrence and biological significance of the α-keto-sugars pseudaminic acid and legionaminic acid within pathogenic bacteria. RSC Adv 2014. [DOI: 10.1039/c3ra44924f] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] 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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Analyzing the modification of the Shewanella oneidensis MR-1 flagellar filament. PLoS One 2013; 8:e73444. [PMID: 24039942 PMCID: PMC3765264 DOI: 10.1371/journal.pone.0073444] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 07/22/2013] [Indexed: 11/19/2022] Open
Abstract
The unsheathed flagellar filament of Shewanella oneidensis MR-1 is composed of two highly homologous flagellins, FlaA, and the major structural unit, FlaB. We identified a gene cluster, SO_3261-SO_3265 (now sfmABCDE), that is required for the formation of a fully functional filament and for motility. The predicted function of the corresponding gene products strongly indicated a role in flagellin modification. Accordingly, loss of sfmABCDE results in a significant mass shift of both FlaA and FlaB. Mass spectroscopy analysis and single residue substitutions identified five serine residues in both flagellins that are modified via O-linkage. Modeling of the flagellin structures strongly suggests that at least four of the modified residues are exposed to the filament's surface. However, none of the five serine residues solely is crucial for function and assembly. Structural analysis of the flagellin modification revealed that it likely contains a nonulosonic acid (274 Da) linked to each glycosylated serine. The putative nonulosonic acid is further substituted with a 236 Da moiety which can carry additional methyl groups (250 Da, 264 Da). In addition, at least 5 lysine residues in FlaB and one in FlaA were found to be methylated. Based on homology comparisons we suggest that smfABCDE is required for species-specific flagellin modification in S. oneidensis MR-1.
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Taveirne ME, Theriot CM, Livny J, DiRita VJ. The complete Campylobacter jejuni transcriptome during colonization of a natural host determined by RNAseq. PLoS One 2013; 8:e73586. [PMID: 23991199 PMCID: PMC3749233 DOI: 10.1371/journal.pone.0073586] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 07/22/2013] [Indexed: 11/19/2022] Open
Abstract
Campylobacter jejuni is a major human pathogen and a leading cause of bacterial derived gastroenteritis worldwide. C. jejuni regulates gene expression under various environmental conditions and stresses, indicative of its ability to survive in diverse niches. Despite this ability to highly regulate gene transcription, C. jejuni encodes few transcription factors and its genome lacks many canonical transcriptional regulators. High throughput deep sequencing of mRNA transcripts (termed RNAseq) has been used to study the transcriptome of many different organisms, including C. jejuni; however, this technology has yet to be applied to defining the transcriptome of C. jejuni during in vivo colonization of its natural host, the chicken. In addition to its use in profiling the abundance of annotated genes, RNAseq is a powerful tool for identifying and quantifying, as-of-yet, unknown transcripts including non-coding regulatory RNAs, 5’ untranslated regulatory elements, and anti-sense transcripts. Here we report the complete transcriptome of C. jejuni during colonization of the chicken cecum and in two different in vitro growth phases using strand-specific RNAseq. Through this study, we identified over 250 genes differentially expressed in vivo in addition to numerous putative regulatory RNAs, including trans-acting non-coding RNAs and anti-sense transcripts. These latter potential regulatory elements were not identified in two prior studies using ORF-based microarrays, highlighting the power and value of the RNAseq approach. Our results provide new insights into how C. jejuni responds and adapts to the cecal environment and reveals new functions involved in colonization of its natural host.
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Affiliation(s)
- Michael E. Taveirne
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - Casey M. Theriot
- Department of Internal Medicine, Division of Infectious Diseases, University of Michigan, Ann Arbor, Michigan, United States of America
- Department of Internal Medicine, Division of Pulmonary and Critical Care, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Jonathan Livny
- Genome Sequencing and Analysis Program, Broad Institute, Cambridge, Massachusetts, United States of America
- * E-mail: (VJD); (JL)
| | - Victor J. DiRita
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
- * E-mail: (VJD); (JL)
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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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46
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Parker JL, Day-Williams MJ, Tomas JM, Stafford GP, Shaw JG. Identification of a putative glycosyltransferase responsible for the transfer of pseudaminic acid onto the polar flagellin of Aeromonas caviae Sch3N. Microbiologyopen 2012; 1:149-60. [PMID: 22950021 PMCID: PMC3426422 DOI: 10.1002/mbo3.19] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Revised: 02/14/2012] [Accepted: 02/15/2012] [Indexed: 12/04/2022] Open
Abstract
Motility in Aeromonas caviae, in a liquid environment (in broth culture), is mediated by a single polar flagellum encoded by the fla genes. The polar flagellum filament of A. caviae is composed of two flagellin subunits, FlaA and FlaB, which undergo O-linked glycosylation with six to eight pseudaminic acid glycans linked to serine and threonine residues in their central region. The flm genetic locus in A. caviae is required for flagellin glycosylation and the addition of pseudaminic acid (Pse) onto the lipopolysaccharide (LPS) O-antigen. However, none of the flm genes appear to encode a candidate glycotransferase that might add the Pse moiety to FlaA/B. The motility-associated factors (Maf proteins) are considered as candidate transferase enzymes, largely due to their conserved proximity to flagellar biosynthesis loci in a number of pathogens. Bioinformatic analysis performed in this study indicated that the genome of A. caviae encodes a single maf gene homologue (maf1). A maf mutant was generated and phenotypic analysis showed it is both nonmotile and lacks polar flagella. In contrast to flm mutants, it had no effect on the LPS O-antigen pattern and has the ability to swarm. Analysis of flaA transcription by reverse transcriptase PCR (RT-PCR) showed that its transcription was unaltered in the maf mutant while a His-tagged version of the FlaA flagellin protein produced from a plasmid was detected in an unglycosylated intracellular form in the maf strain. Complementation of the maf strain in trans partially restored motility, but increased levels of glycosylated flagellin to above wild-type levels. Overexpression of maf inhibited motility, indicating a dominant negative effect, possibly caused by high amounts of glycosylated flagellin inhibiting assembly of the flagellum. These data provide evidence that maf1, a pseudaminyl transferase, is responsible for glycosylation of flagellin and suggest that this event occurs prior to secretion through the flagellar Type III secretion system.
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Tomás JM. The main Aeromonas pathogenic factors. ISRN MICROBIOLOGY 2012; 2012:256261. [PMID: 23724321 PMCID: PMC3658858 DOI: 10.5402/2012/256261] [Citation(s) in RCA: 175] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Accepted: 07/19/2012] [Indexed: 12/27/2022]
Abstract
The members of the Aeromonas genus are ubiquitous, water-borne bacteria. They have been isolated from marine waters, rivers, lakes, swamps, sediments, chlorine water, water distribution systems, drinking water and residual waters; different types of food, such as meat, fish, seafood, vegetables, and processed foods. Aeromonas strains are predominantly pathogenic to poikilothermic animals, and the mesophilic strains are emerging as important pathogens in humans, causing a variety of extraintestinal and systemic infections as well as gastrointestinal infections. The most commonly described disease caused by Aeromonas is the gastroenteritis; however, no adequate animal model is available to reproduce this illness caused by Aeromonas. The main pathogenic factors associated with Aeromonas are: surface polysaccharides (capsule, lipopolysaccharide, and glucan), S-layers, iron-binding systems, exotoxins and extracellular enzymes, secretion systems, fimbriae and other nonfilamentous adhesins, motility and flagella.
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Affiliation(s)
- J M Tomás
- Departamento Microbiología, Universidad de Barcelona, Diagonal 643, 08071 Barcelona, Spain
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Identification of genes involved in the acetamidino group modification of the flagellin N-linked glycan of Methanococcus maripaludis. J Bacteriol 2012; 194:2693-702. [PMID: 22408155 DOI: 10.1128/jb.06686-11] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
N-linked glycosylation of protein is a posttranslational modification found in all three domains of life. The flagellin proteins of the archaeon Methanococcus maripaludis are known to be modified with an N-linked tetrasaccharide consisting of N-acetylgalactosamine (GalNAc), a diacetylated glucuronic acid (GlcNAc3NAc), an acetylated and acetamidino-modified mannuronic acid with a substituted threonine group (ManNAc3NAmA6Thr), and a novel terminal sugar residue [(5S)-2-acetamido-2,4-dideoxy-5-O-methyl-α-L-erythro-hexos-5-ulo-1,5-pyranose]. To identify genes involved in biosynthesis of the component sugars of this glycan, three genes, mmp1081, mmp1082, and mmp1083, were targeted for in-frame deletion, based on their annotation and proximity to glycosyltransferase genes known to be involved in assembly of the glycan. Mutants carrying a deletion in any of these three genes remained flagellated and motile. A strain with a deletion of mmp1081 had lower-molecular-mass flagellins in Western blots. Mass spectrometry of purified flagella revealed a truncated glycan with the terminal sugar absent and the threonine residue and the acetamidino group missing from the third sugar. No glycan modification was seen in either the Δmmp1082 or Δmmp1083 mutant grown in complex Balch III medium. However, a glycan identical to the Δmmp1081 glycan was observed when the Δmmp1082 or Δmmp1083 mutant was grown under ammonia-limited conditions. We hypothesize that MMP1082 generates ammonia and tunnels it through MMP1083 to MMP1081, which acts as the amidotransferase, modifying the third sugar residue of the M. maripaludis glycan with the acetamidino group.
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Hopf PS, Ford RS, Zebian N, Merkx-Jacques A, Vijayakumar S, Ratnayake D, Hayworth J, Creuzenet C. Protein glycosylation in Helicobacter pylori: beyond the flagellins? PLoS One 2011; 6:e25722. [PMID: 21984942 PMCID: PMC3184161 DOI: 10.1371/journal.pone.0025722] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Accepted: 09/09/2011] [Indexed: 12/13/2022] Open
Abstract
Glycosylation of flagellins by pseudaminic acid is required for virulence in Helicobacter pylori. We demonstrate that, in H. pylori, glycosylation extends to proteins other than flagellins and to sugars other than pseudaminic acid. Several candidate glycoproteins distinct from the flagellins were detected via ProQ-emerald staining and DIG- or biotin- hydrazide labeling of the soluble and outer membrane fractions of wild-type H. pylori, suggesting that protein glycosylation is not limited to the flagellins. DIG-hydrazide labeling of proteins from pseudaminic acid biosynthesis pathway mutants showed that the glycosylation of some glycoproteins is not dependent on the pseudaminic acid glycosylation pathway, indicating the existence of a novel glycosylation pathway. Fractions enriched in glycoprotein candidates by ion exchange chromatography were used to extract the sugars by acid hydrolysis. High performance anion exchange chromatography with pulsed amperometric detection revealed characteristic monosaccharide peaks in these extracts. The monosaccharides were then identified by LC-ESI-MS/MS. The spectra are consistent with sugars such as 5,7-diacetamido-3,5,7,9-tetradeoxy-L-glycero-L-manno-nonulosonic acid (Pse5Ac7Ac) previously described on flagellins, 5-acetamidino-7-acetamido-3,5,7,9-tetradeoxy-L-glycero-L-manno-nonulosonic acid (Pse5Am7Ac), bacillosamine derivatives and a potential legionaminic acid derivative (Leg5AmNMe7Ac) which were not previously identified in H. pylori. These data open the way to the study of the mechanism and role of protein glycosylation on protein function and virulence in H. pylori.
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Affiliation(s)
- Patrick S. Hopf
- Infectious Diseases Research Group, Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada
| | - Rachel S. Ford
- Infectious Diseases Research Group, Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada
| | - Najwa Zebian
- Infectious Diseases Research Group, Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada
| | - Alexandra Merkx-Jacques
- Infectious Diseases Research Group, Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada
| | - Somalinga Vijayakumar
- Infectious Diseases Research Group, Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada
| | - Dinath Ratnayake
- Infectious Diseases Research Group, Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada
| | - Jacqueline Hayworth
- Infectious Diseases Research Group, Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada
| | - Carole Creuzenet
- Infectious Diseases Research Group, Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada
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50
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Genomic and metabolic profiling of nonulosonic acids in Vibrionaceae reveal biochemical phenotypes of allelic divergence in Vibrio vulnificus. Appl Environ Microbiol 2011; 77:5782-93. [PMID: 21724895 DOI: 10.1128/aem.00712-11] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Nonulosonic acids (NulOs) encompass a large group of structurally diverse nine-carbon backbone α-keto sugars widely distributed among the three domains of life. Mammals express a specialized version of NulOs called sialic acids, which are displayed in prominent terminal positions of cell surface and secreted glycoconjugates. Within bacteria, the ability to synthesize NulOs has been demonstrated in a number of human pathogens and is phylogenetically widespread. Here we examine the distribution, diversity, evolution, and function of NulO biosynthesis pathways in members of the family Vibrionaceae. Among 27 species of Vibrionaceae examined at the genomic level, 12 species contained nab gene clusters. We document examples of duplication, divergence, horizontal transfer, and recombination of nab gene clusters in different Vibrionaceae lineages. Biochemical analyses, including mass spectrometry, confirmed that many species do, in fact, produce di-N-acetylated NulOs. A library of clinical and environmental isolates of Vibrio vulnificus served as a model for further investigation of nab allele genotypes and levels of NulO expression. The data show that lineage I isolates produce about 20-fold higher levels of NulOs than lineage II isolates. Moreover, nab gene alleles found in a subset of V. vulnificus clinical isolates express 40-fold higher levels of NulOs than nab alleles associated with environmental isolates. Taken together, the data implicate the family Vibrionaceae as a "hot spot" of NulO evolution and suggest that these molecules may have diverse roles in environmental persistence and/or animal virulence.
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