1
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Kelly SD, Ovchinnikova OG, Müller F, Steffen M, Braun M, Sweeney RP, Kowarik M, Follador R, Lowary TL, Serventi F, Whitfield C. Identification of a second glycoform of the clinically prevalent O1 antigen from Klebsiella pneumoniae. Proc Natl Acad Sci U S A 2023; 120:e2301302120. [PMID: 37428935 PMCID: PMC10629545 DOI: 10.1073/pnas.2301302120] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 05/15/2023] [Indexed: 07/12/2023] Open
Abstract
Carbapenemase and extended β-lactamase-producing Klebsiella pneumoniae isolates represent a major health threat, stimulating increasing interest in immunotherapeutic approaches for combating Klebsiella infections. Lipopolysaccharide O antigen polysaccharides offer viable targets for immunotherapeutic development, and several studies have described protection with O-specific antibodies in animal models of infection. O1 antigen is produced by almost half of clinical Klebsiella isolates. The O1 polysaccharide backbone structure is known, but monoclonal antibodies raised against the O1 antigen showed varying reactivity against different isolates that could not be explained by the known structure. Reinvestigation of the structure by NMR spectroscopy revealed the presence of the reported polysaccharide backbone (glycoform O1a), as well as a previously unknown O1b glycoform composed of the O1a backbone modified with a terminal pyruvate group. The activity of the responsible pyruvyltransferase (WbbZ) was confirmed by western immunoblotting and in vitro chemoenzymatic synthesis of the O1b terminus. Bioinformatic data indicate that almost all O1 isolates possess genes required to produce both glycoforms. We describe the presence of O1ab-biosynthesis genes in other bacterial species and report a functional O1 locus on a bacteriophage genome. Homologs of wbbZ are widespread in genetic loci for the assembly of unrelated glycostructures in bacteria and yeast. In K. pneumoniae, simultaneous production of both O1 glycoforms is enabled by the lack of specificity of the ABC transporter that exports the nascent glycan, and the data reported here provide mechanistic understanding of the capacity for evolution of antigenic diversity within an important class of biomolecules produced by many bacteria.
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Affiliation(s)
- Steven D. Kelly
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ONN1G 2W1, Canada
| | - Olga G. Ovchinnikova
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ONN1G 2W1, Canada
| | | | | | - Martin Braun
- LimmaTech Biologics AG, Schlieren8952, Switzerland
| | - Ryan P. Sweeney
- Department of Chemistry, University of Alberta, Edmonton, ABT6G 2G2, Canada
| | | | | | - Todd L. Lowary
- Department of Chemistry, University of Alberta, Edmonton, ABT6G 2G2, Canada
- Institute of Biological Chemistry, Academia Sinica, Taipei, Nangang11529, Taiwan
- Institute of Biochemical Sciences, National Taiwan University, Taipei10617, Taiwan
| | | | - Chris Whitfield
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ONN1G 2W1, Canada
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2
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Palusiak A. Proteus mirabilis and Klebsiella pneumoniae as pathogens capable of causing co-infections and exhibiting similarities in their virulence factors. Front Cell Infect Microbiol 2022; 12:991657. [PMID: 36339335 PMCID: PMC9630907 DOI: 10.3389/fcimb.2022.991657] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 10/03/2022] [Indexed: 09/23/2023] Open
Abstract
The genera Klebsiella and Proteus were independently described in 1885. These Gram-negative rods colonize the human intestinal tract regarded as the main reservoir of these opportunistic pathogens. In favorable conditions they cause infections, often hospital-acquired ones. The activity of K. pneumoniae and P. mirabilis, the leading pathogens within each genus, results in infections of the urinary (UTIs) and respiratory tracts, wounds, bacteremia, affecting mainly immunocompromised patients. P. mirabilis and K. pneumoniae cause polymicrobial UTIs, which are often persistent due to the catheter biofilm formation or increasing resistance of the bacteria to antibiotics. In this situation a need arises to find the antigens with features common to both species. Among many virulence factors produced by both pathogens urease shows some structural similarities but the biggest similarities have been observed in lipids A and the core regions of lipopolysaccharides (LPSs). Both species produce capsular polysaccharides (CPSs) but only in K. pneumoniae these antigens play a crucial role in the serological classification scheme, which in Proteus spp. is based on the structural and serological diversity of LPS O-polysaccharides (OPSs). Structural and serological similarities observed for Klebsiella spp. and Proteus spp. polysaccharides are important in the search for the cross-reacting vaccine antigens.
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Affiliation(s)
- Agata Palusiak
- Laboratory of General Microbiology, Department of Biology of Bacteria, Institute of Microbiology, Biotechnology and Immunology, University of Łódź, Łódź, Poland
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3
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Knoot CJ, Wantuch PL, Robinson LS, Rosen DA, Scott NE, Harding CM. Discovery and characterization of a new class of O-linking oligosaccharyltransferases from the Moraxellaceae family. Glycobiology 2022; 33:57-74. [PMID: 36239418 PMCID: PMC9829042 DOI: 10.1093/glycob/cwac070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 10/07/2022] [Accepted: 10/11/2022] [Indexed: 01/12/2023] Open
Abstract
Bacterial protein glycosylation is commonly mediated by oligosaccharyltransferases (OTases) that transfer oligosaccharides en bloc from preassembled lipid-linked precursors to acceptor proteins. Natively, O-linking OTases usually transfer a single repeat unit of the O-antigen or capsular polysaccharide to the side chains of serine or threonine on acceptor proteins. Three major families of bacterial O-linking OTases have been described: PglL, PglS, and TfpO. TfpO is limited to transferring short oligosaccharides both in its native context and when heterologously expressed in glycoengineered Escherichia coli. On the other hand, PglL and PglS can transfer long-chain polysaccharides when expressed in glycoengineered E. coli. Herein, we describe the discovery and functional characterization of a novel family of bacterial O-linking OTases termed TfpM from Moraxellaceae bacteria. TfpM proteins are similar in size and sequence to TfpO enzymes but can transfer long-chain polysaccharides to acceptor proteins. Phylogenetic analyses demonstrate that TfpM proteins cluster in distinct clades from known bacterial OTases. Using a representative TfpM enzyme from Moraxella osloensis, we determined that TfpM glycosylates a C-terminal threonine of its cognate pilin-like protein and identified the minimal sequon required for glycosylation. We further demonstrated that TfpM has broad substrate tolerance and can transfer diverse glycans including those with glucose, galactose, or 2-N-acetyl sugars at the reducing end. Last, we find that a TfpM-derived bioconjugate is immunogenic and elicits serotype-specific polysaccharide IgG responses in mice. The glycan substrate promiscuity of TfpM and identification of the minimal TfpM sequon renders this enzyme a valuable additional tool for expanding the glycoengineering toolbox.
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Affiliation(s)
- Cory J Knoot
- Omniose, 4340 Duncan Ave, Suite 202, St. Louis, MO 63110, USA
| | - Paeton L Wantuch
- Department of Pediatrics, Division of Infectious Diseases, Washington University School of Medicine, 4990 Children’s Place, St. Louis, MO 63110, USA
| | | | - David A Rosen
- Department of Pediatrics, Division of Infectious Diseases, Washington University School of Medicine, 4990 Children’s Place, St. Louis, MO 63110, USA,Department of Molecular Microbiology, Washington University School of Medicine, 660 Euclid Ave, St. Louis, MO 63110, USA
| | - Nichollas E Scott
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, VIC 3010, Australia
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4
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Peng Z, Wu J, Wang K, Li X, Sun P, Zhang L, Huang J, Liu Y, Hua X, Yu Y, Pan C, Wang H, Zhu L. Production of a Promising Biosynthetic Self-Assembled Nanoconjugate Vaccine against Klebsiella Pneumoniae Serotype O2 in a General Escherichia Coli Host. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2100549. [PMID: 34032027 PMCID: PMC8292882 DOI: 10.1002/advs.202100549] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 04/09/2021] [Indexed: 05/09/2023]
Abstract
Klebsiella pneumoniae has emerged as a severe opportunistic pathogen with multiple drug resistances. Finding effective vaccines against this pathogen is urgent. Although O-polysaccharides (OPS) of K. pneumoniae are suitable antigens for the preparation of vaccines given their low levels of diversity, the low immunogenicity (especially serotype O2) limit their application. In this study, a general Escherichia coli host system is developed to produce a nanoscale conjugate vaccine against K. pneumoniae using the Nano-B5 self-assembly platform. The experimental data illustrate that this nanoconjugate vaccine can induce an efficient humoral immune response in draining lymph nodes (dLNs) and elicit high titers of the IgG antibody against bacterial lipopolysaccharide (LPS). The ideal prophylactic effects of these nanoconjugate vaccines are further demonstrated in mouse models of both systemic and pulmonary infection. These results demonstrate that OPS with low immunogenicity can be changed into an effective antigen, indicating that other haptens may be applicable to this strategy in the future. To the knowledge, this is the first study to produce biosynthetic nanoconjugate vaccines against K. pneumoniae in E. coli, and this strategy can be applied to the development of other vaccines against pathogenic bacteria.
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Affiliation(s)
- Zhehui Peng
- State Key Laboratory of Pathogen and BiosecurityBeijing Institute of BiotechnologyNo. 20, Dongda Street, Fengtai DistrictBeijing100071P. R. China
| | - Jun Wu
- State Key Laboratory of Pathogen and BiosecurityBeijing Institute of BiotechnologyNo. 20, Dongda Street, Fengtai DistrictBeijing100071P. R. China
| | - Kangfeng Wang
- State Key Laboratory of Pathogen and BiosecurityBeijing Institute of BiotechnologyNo. 20, Dongda Street, Fengtai DistrictBeijing100071P. R. China
| | - Xin Li
- State Key Laboratory of Pathogen and BiosecurityBeijing Institute of BiotechnologyNo. 20, Dongda Street, Fengtai DistrictBeijing100071P. R. China
| | - Peng Sun
- State Key Laboratory of Pathogen and BiosecurityBeijing Institute of BiotechnologyNo. 20, Dongda Street, Fengtai DistrictBeijing100071P. R. China
| | - Lulu Zhang
- State Key Laboratory of Pathogen and BiosecurityBeijing Institute of BiotechnologyNo. 20, Dongda Street, Fengtai DistrictBeijing100071P. R. China
| | - Jing Huang
- State Key Laboratory of Pathogen and BiosecurityBeijing Institute of BiotechnologyNo. 20, Dongda Street, Fengtai DistrictBeijing100071P. R. China
| | - Yan Liu
- State Key Laboratory of Pathogen and BiosecurityBeijing Institute of BiotechnologyNo. 20, Dongda Street, Fengtai DistrictBeijing100071P. R. China
| | - Xiaoting Hua
- Department of Infectious DiseasesSir Run Run Shaw HospitalCollege of MedicineZhejiang University866 Yuhangtang RdHangzhou310058P. R. China
| | - Yunsong Yu
- Department of Infectious DiseasesSir Run Run Shaw HospitalCollege of MedicineZhejiang University866 Yuhangtang RdHangzhou310058P. R. China
| | - Chao Pan
- State Key Laboratory of Pathogen and BiosecurityBeijing Institute of BiotechnologyNo. 20, Dongda Street, Fengtai DistrictBeijing100071P. R. China
| | - Hengliang Wang
- State Key Laboratory of Pathogen and BiosecurityBeijing Institute of BiotechnologyNo. 20, Dongda Street, Fengtai DistrictBeijing100071P. R. China
| | - Li Zhu
- State Key Laboratory of Pathogen and BiosecurityBeijing Institute of BiotechnologyNo. 20, Dongda Street, Fengtai DistrictBeijing100071P. R. China
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5
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An ABC transporter Wzm-Wzt catalyzes translocation of lipid-linked galactan across the plasma membrane in mycobacteria. Proc Natl Acad Sci U S A 2021; 118:2023663118. [PMID: 33879617 DOI: 10.1073/pnas.2023663118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Mycobacterium tuberculosis, one of the deadliest pathogens in human history, is distinguished by a unique, multilayered cell wall, which offers the bacterium a high level of protection from the attacks of the host immune system. The primary structure of the cell wall core, composed of covalently linked peptidoglycan, branched heteropolysaccharide arabinogalactan, and mycolic acids, is well known, and numerous enzymes involved in the biosynthesis of its components are characterized. The cell wall biogenesis takes place at both cytoplasmic and periplasmic faces of the plasma membrane, and only recently some of the specific transport systems translocating the metabolic intermediates between these two compartments have been characterized [M. Jackson, C. M. Stevens, L. Zhang, H. I. Zgurskaya, M. Niederweis, Chem. Rev., 10.1021/acs.chemrev.0c00869 (2020)]. In this work, we use CRISPR interference methodology in Mycobacterium smegmatis to functionally characterize an ATP-binding cassette (ABC) transporter involved in the translocation of galactan precursors across the plasma membrane. We show that genetic knockdown of the transmembrane subunit of the transporter results in severe morphological changes and the accumulation of an aberrantly long galactan precursor. Based on similarities with structures and functions of specific O-antigen ABC transporters of gram-negative bacteria [C. Whitfield, D. M. Williams, S. D. Kelly, J. Biol. Chem. 295, 10593-10609 (2020)], we propose a model for coupled synthesis and export of the galactan polymer precursor in mycobacteria.
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6
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Hao G, Yuan C, Shu R, Jia Y, Zhao S, Xie S, Liu M, Zhou H, Sun S, Wang H. O-antigen serves as a two-faced host factor for bacteriophage NJS1 infecting nonmucoid Klebsiella pneumoniae. Microb Pathog 2021; 155:104897. [PMID: 33878399 DOI: 10.1016/j.micpath.2021.104897] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Revised: 03/24/2021] [Accepted: 03/25/2021] [Indexed: 11/16/2022]
Abstract
Klebsiella pneumoniae is an opportunistic pathogen commonly associated with nosocomial infections. In our previous study, we have demonstrated that colistin-resistant K. pneumoniae is more susceptible to killing by lytic tailed phages than the colistin-sensitive parent strain, including T1-like ФNJS1. This fitness cost associated with colistin resistance is due to the alteration of the surface charge that promotes phage adherence and infection. However, the receptor for phage adsorption has not been identified. In this study, we found that ФNJS1 specifically infected nonmucoid K. pneumoniae isolates, and the accelerated phage adsorption to colistin-resistant nonmucoid K. pneumoniae cells is reversible. Further research suggested that bacteria lipopolysaccharide may be involved in phage reversible adsorption, while capsule polysaccharide may block the receptors on cell surface from phage attachment. Transposon mutagenesis of colistin-resistant K. pneumoniae revealed that mutation in wecA and wecG, two genes involved in lipopolysaccharide O-antigen biosynthesis, significantly deceased phage adsorption capacity and infection efficiency. Inactivation of wzyE, which leaded to the shorten of O-antigen chain length, enhanced phage infectivity. Moreover, mutation of the outer membrane protein FepA slowed the phage lysis rate, suggesting that FepA may be an irreversible receptor for ФNJS1. In summary, our results show a delicate balance between ФNJS1 and its hosts, where the lipopolysaccharide O-antigen may serve as an essential reversible receptor for phage NJS1, while the long O-antigen chain hinders the bacteriophage infection.
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Affiliation(s)
- Guijuan Hao
- Department of Microbiology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Chaoqun Yuan
- Department of Microbiology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Rundong Shu
- Department of Microbiology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yuanqi Jia
- Department of Microbiology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Suqin Zhao
- Department of Microbiology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Saijun Xie
- Department of Microbiology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Ming Liu
- Department of Microbiology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Haijian Zhou
- State Key Laboratory for Infectious Disease Prevention and Control, Chinese Center for Disease Control and Prevention, Beijing, 102206, China
| | - Shuhong Sun
- College of Animal Science and Technology, Shandong Agricultural University, Taian, Shandong, 271018, China
| | - Hui Wang
- Department of Microbiology, Nanjing Agricultural University, Nanjing, 210095, China.
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7
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Choi M, Hegerle N, Nkeze J, Sen S, Jamindar S, Nasrin S, Sen S, Permala-Booth J, Sinclair J, Tapia MD, Johnson JK, Mamadou S, Thaden JT, Fowler VG, Aguilar A, Terán E, Decre D, Morel F, Krogfelt KA, Brauner A, Protonotariou E, Christaki E, Shindo Y, Lin YT, Kwa AL, Shakoor S, Singh-Moodley A, Perovic O, Jacobs J, Lunguya O, Simon R, Cross AS, Tennant SM. The Diversity of Lipopolysaccharide (O) and Capsular Polysaccharide (K) Antigens of Invasive Klebsiella pneumoniae in a Multi-Country Collection. Front Microbiol 2020; 11:1249. [PMID: 32595624 PMCID: PMC7303279 DOI: 10.3389/fmicb.2020.01249] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 05/15/2020] [Indexed: 12/20/2022] Open
Abstract
Klebsiella pneumoniae is a common cause of sepsis and is particularly associated with healthcare-associated infections. New strategies are needed to prevent or treat infections due to the emergence of multi-drug resistant K. pneumoniae. The goal of this study was to determine the diversity and distribution of O (lipopolysaccharide) and K (capsular polysaccharide) antigens on a large (>500) global collection of K. pneumoniae strains isolated from blood to inform vaccine development efforts. A total of 645 K. pneumoniae isolates were collected from the blood of patients in 13 countries during 2005-2017. Antibiotic susceptibility was determined using the Kirby-Bauer disk diffusion method. O antigen types including the presence of modified O galactan types were determined by PCR. K types were determined by multiplex PCR and wzi capsular typing. Sequence types of isolates were determined by multilocus sequence typing (MLST) targeting seven housekeeping genes. Among 591 isolates tested for antimicrobial resistance, we observed that 19.3% of isolates were non-susceptible to carbapenems and 62.1% of isolates were multidrug resistant (from as low as 16% in Sweden to 94% in Pakistan). Among 645 isolates, four serotypes, O1, O2, O3, and O5, accounted for 90.1% of K. pneumoniae strains. Serotype O1 was associated with multidrug resistance. Fifty percent of 199 tested O1 and O2 strains were gmlABC-positive, indicating the presence of the modified polysaccharide subunit D-galactan III. The most common K type was K2 by both multiplex PCR and wzi capsular typing. Of 39 strains tested by MLST, 36 strains were assigned to 26 known sequence types of which ST14, ST25, and ST258 were the most common. Given the limited number of O antigen types, diverse K antigen types and the high multidrug resistance, we believe that an O antigen-based vaccine would offer an excellent prophylactic strategy to prevent K. pneumoniae invasive infection.
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Affiliation(s)
- Myeongjin Choi
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States.,Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Nicolas Hegerle
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States.,Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Joseph Nkeze
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States.,Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Shaichi Sen
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States.,Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Sanchita Jamindar
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States.,Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Shamima Nasrin
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States.,Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Sunil Sen
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States.,Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Jasnehta Permala-Booth
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States.,Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - James Sinclair
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States.,Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Milagritos D Tapia
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States.,Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD, United States
| | - J Kristie Johnson
- Department of Pathology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Sylla Mamadou
- Centre pour le Développement des Vaccins, Bamako, Mali
| | - Joshua T Thaden
- Division of Infectious Diseases, Duke University Medical Center, Durham, NC, United States
| | - Vance G Fowler
- Department of Medicine, Division of Infectious Diseases and International Health, Duke University School of Medicine, Durham, NC, United States.,Duke Clinical Research Institute, Durham, NC, United States
| | - Ana Aguilar
- Colegio de Ciencias de la Salud e Instituto de Microbiologia, Universidad San Francisco de Quito, Quito, Ecuador
| | - Enrique Terán
- Colegio de Ciencias de la Salud e Instituto de Microbiologia, Universidad San Francisco de Quito, Quito, Ecuador
| | - Dominique Decre
- Département de Bactériologie, Centre d'Immunologie et des Maladies Infectieuses-Paris, Cimi-Paris, INSERM U1135, AP-HP, Sorbonne Université, Hôpitaux Universitaires Est Parisien, Paris, France
| | - Florence Morel
- Département de Bactériologie, Centre d'Immunologie et des Maladies Infectieuses-Paris, Cimi-Paris, INSERM U1135, AP-HP, Sorbonne Université, Hôpitaux Universitaires Est Parisien, Paris, France
| | | | - Annelie Brauner
- Department of Microbiology, Tumor and Cell Biology, Division of Clinical Microbiology, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | | | - Eirini Christaki
- Department of Medicine, AHEPA University Hospital, Thessaloniki, Greece.,Medical School, University of Cyprus, Nicosia, Cyprus
| | - Yuichiro Shindo
- Department of Respiratory Medicine, Graduate School of Medicine, Nagoya University, Nagoya, Japan
| | - Yi-Tsung Lin
- Division of Infectious Diseases, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Institute of Emergency and Critical Care Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Andrea L Kwa
- Department of Pharmacy, Singapore General Hospital, Singapore, Singapore.,Emerging Infectious Diseases, Duke-National University of Singapore Medical School, Singapore, Singapore.,Department of Pharmacy, Faculty of Science, National University of Singapore, Singapore, Singapore
| | - Sadia Shakoor
- Departments of Pathology and Pediatrics, Aga Khan University, Karachi, Pakistan
| | - Ashika Singh-Moodley
- National Institute for Communicable Diseases, A Division of the National Health Laboratory Service, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, Johannesburg, South Africa
| | - Olga Perovic
- National Institute for Communicable Diseases, A Division of the National Health Laboratory Service, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, Johannesburg, South Africa
| | - Jan Jacobs
- Department of Clinical Sciences, Institute of Tropical Medicine Antwerp, Antwerp, Belgium.,Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
| | - Octavie Lunguya
- Department of Clinical Microbiology and Microbiology, National Institute for Biomedical Research, University Hospital of Kinshasa, Kinshasa, Democratic Republic of Congo
| | - Raphael Simon
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States.,Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Alan S Cross
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States.,Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Sharon M Tennant
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, United States.,Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
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8
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Choi M, Tennant SM, Simon R, Cross AS. Progress towards the development of Klebsiella vaccines. Expert Rev Vaccines 2019; 18:681-691. [PMID: 31250679 DOI: 10.1080/14760584.2019.1635460] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Introduction: Klebsiella pneumoniae (KP) are a leading cause of healthcare-associated infections. The dramatic increase in microbial resistance to third-generation cephalosporin and carbapenem 'front line' antimicrobial agents and the paucity of new antimicrobials have left clinicians with few therapeutic options and resulted in increased morbidity and mortality. Vaccines may reduce the incidence of infections thereby reducing the necessity for antimicrobials and are not subject to antimicrobial resistance mechanisms. Areas covered: We review whole cell, subunit, capsular polysaccharide (CPS), O polysaccharide (OPS) and conjugate vaccines against KP infection, as well as alternative KP vaccine platforms. Expert opinion: Vaccine-induced antibodies to KP CPS have been protective in preclinical studies, but the number of CPS types (>77) makes vaccines against this virulence factor less feasible. Since four OPS serotypes account of ~80% of invasive KP infections and anti-OPS antibodies are also protective in preclinical studies, both OPS-based conjugate and multiple antigen presenting system (MAPS) vaccines are in active development. Vaccines based on other KP virulence factors, such as outer membrane proteins, type 3 fimbriae (MrkA) and siderophores are at earlier stages of development. Novel strategies for the clinical testing of KP vaccines need to be developed.
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Affiliation(s)
- Myeongjin Choi
- a Center for Vaccine Development and Global Health, University of Maryland School of Medicine , Baltimore , MD , USA
| | - Sharon M Tennant
- a Center for Vaccine Development and Global Health, University of Maryland School of Medicine , Baltimore , MD , USA
| | - Raphael Simon
- a Center for Vaccine Development and Global Health, University of Maryland School of Medicine , Baltimore , MD , USA
| | - Alan S Cross
- a Center for Vaccine Development and Global Health, University of Maryland School of Medicine , Baltimore , MD , USA
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9
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Aytenfisu AH, Simon R, MacKerell AD. Impact of branching on the conformational heterogeneity of the lipopolysaccharide from Klebsiella pneumoniae: Implications for vaccine design. Carbohydr Res 2019; 475:39-47. [PMID: 30818097 DOI: 10.1016/j.carres.2019.02.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 02/09/2019] [Accepted: 02/13/2019] [Indexed: 02/08/2023]
Abstract
Resistance of Klebsiella pneumoniae (KP) to antibiotics has motivated the development of an efficacious KP human vaccine that would not be subject to antibiotic resistance. Klebsiella lipopolysaccharide (LPS) associated O polysaccharide (OPS) types have provoked broad interest as a vaccine antigen as there are only 4 that predominate worldwide (O1, O2a, O3, O5). Klebsiella O1 and O2 OPS are polygalactans that share a common D-Gal-I structure, for which a variant D-Gal-III was recently discovered. To understand the potential impact of this variability on antigenicity, a detailed molecular picture of the conformational differences associated with the addition of the D-Gal-III (1 → 4)-α-Galp branch is presented using enhanced-sampling molecular dynamics simulations. In D-Gal-I two major conformational states are observed while the presence of the 1 → 4 branch in D-Gal-III resulted in only a single dominant extended state. Stabilization of the more folded states in D-Gal-I is due to a O4-H⋯O2 hydrogen bond in the linear backbone that cannot occur in D-Gal-III as the O4 is in the Galp(1 → 4)Galp glycosidic linkage. The impact of branching in D-Gal-III also significantly decreases the accessibility of the monosaccharides in the linear backbone region of D-Gal-I, while the accessibility of the terminal D-Gal-II region of the OPS is not substantially altered. The present results suggest that a vaccine that targets both the D-Gal-I and D-Gal-III LPS can be developed by using D-Gal-III as the antigen combined with cross-reactivity experiments using the Gal-II polysaccharide to assure that this region of the LPS is the primary epitope of the antigen.
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Affiliation(s)
- Asaminew H Aytenfisu
- University of Maryland Computer-Aided Drug Design Center, Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, MD, 21201, United States
| | - Raphael Simon
- Center for Vaccine Development, Institute for Global Health, School of Medicine, University of Maryland, Baltimore, MD, 21201, United States
| | - Alexander D MacKerell
- University of Maryland Computer-Aided Drug Design Center, Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, MD, 21201, United States.
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10
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Micoli F, Costantino P, Adamo R. Potential targets for next generation antimicrobial glycoconjugate vaccines. FEMS Microbiol Rev 2018; 42:388-423. [PMID: 29547971 PMCID: PMC5995208 DOI: 10.1093/femsre/fuy011] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 03/13/2018] [Indexed: 12/21/2022] Open
Abstract
Cell surface carbohydrates have been proven optimal targets for vaccine development. Conjugation of polysaccharides to a carrier protein triggers a T-cell-dependent immune response to the glycan moiety. Licensed glycoconjugate vaccines are produced by chemical conjugation of capsular polysaccharides to prevent meningitis caused by meningococcus, pneumococcus and Haemophilus influenzae type b. However, other classes of carbohydrates (O-antigens, exopolysaccharides, wall/teichoic acids) represent attractive targets for developing vaccines. Recent analysis from WHO/CHO underpins alarming concern toward antibiotic-resistant bacteria, such as the so called ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp.) and additional pathogens such as Clostridium difficile and Group A Streptococcus. Fungal infections are also becoming increasingly invasive for immunocompromised patients or hospitalized individuals. Other emergencies could derive from bacteria which spread during environmental calamities (Vibrio cholerae) or with potential as bioterrorism weapons (Burkholderia pseudomallei and mallei, Francisella tularensis). Vaccination could aid reducing the use of broad-spectrum antibiotics and provide protection by herd immunity also to individuals who are not vaccinated. This review analyzes structural and functional differences of the polysaccharides exposed on the surface of emerging pathogenic bacteria, combined with medical need and technological feasibility of corresponding glycoconjugate vaccines.
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Affiliation(s)
- Francesca Micoli
- GSK Vaccines Institute for Global Health (GVGH), Via Fiorentina 1, 53100 Siena
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11
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Clarke BR, Ovchinnikova OG, Kelly SD, Williamson ML, Butler JE, Liu B, Wang L, Gou X, Follador R, Lowary TL, Whitfield C. Molecular basis for the structural diversity in serogroup O2-antigen polysaccharides in Klebsiella pneumoniae. J Biol Chem 2018; 293:4666-4679. [PMID: 29602878 DOI: 10.1074/jbc.ra117.000646] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 01/23/2018] [Indexed: 12/17/2022] Open
Abstract
Klebsiella pneumoniae is a major health threat. Vaccination and passive immunization are considered as alternative therapeutic strategies for managing Klebsiella infections. Lipopolysaccharide O antigens are attractive candidates because of the relatively small range of known O-antigen polysaccharide structures, but immunotherapeutic applications require a complete understanding of the structures found in clinical settings. Currently, the precise number of Klebsiella O antigens is unknown because available serological tests have limited resolution, and their association with defined chemical structures is sometimes uncertain. Molecular serotyping methods can evaluate clinical prevalence of O serotypes but require a full understanding of the genetic determinants for each O-antigen structure. This is problematic with Klebsiella pneumoniae because genes outside the main rfb (O-antigen biosynthesis) locus can have profound effects on the final structure. Here, we report two new loci encoding enzymes that modify a conserved polysaccharide backbone comprising disaccharide repeat units [→3)-α-d-Galp-(1→3)-β-d-Galf-(1→] (O2a antigen). We identified in serotype O2aeh a three-component system that modifies completed O2a glycan in the periplasm by adding 1,2-linked α-Galp side-group residues. In serotype O2ac, a polysaccharide comprising disaccharide repeat units [→5)-β-d-Galf-(1→3)-β-d-GlcpNAc-(1→] (O2c antigen) is attached to the non-reducing termini of O2a-antigen chains. O2c-polysaccharide synthesis is dependent on a locus encoding three glycosyltransferase enzymes. The authentic O2aeh and O2c antigens were recapitulated in recombinant Escherichia coli hosts to establish the essential gene set for their synthesis. These findings now provide a complete understanding of the molecular genetic basis for the known variations in Klebsiella O-antigen carbohydrate structures based on the O2a backbone.
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Affiliation(s)
- Bradley R Clarke
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
| | - Olga G Ovchinnikova
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
| | - Steven D Kelly
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
| | - Monica L Williamson
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
| | - Jennifer E Butler
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
| | - Bin Liu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda St. TEDA, Tianjin 300457, China
| | - Lu Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda St. TEDA, Tianjin 300457, China
| | - Xi Gou
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda St. TEDA, Tianjin 300457, China
| | | | - Todd L Lowary
- Department of Chemistry and Alberta Glycomics Centre, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Chris Whitfield
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1.
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12
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Stojkovic K, Szijártó V, Kaszowska M, Niedziela T, Hartl K, Nagy G, Lukasiewicz J. Identification of d-Galactan-III As Part of the Lipopolysaccharide of Klebsiella pneumoniae Serotype O1. Front Microbiol 2017; 8:684. [PMID: 28487676 PMCID: PMC5403891 DOI: 10.3389/fmicb.2017.00684] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 04/04/2017] [Indexed: 11/15/2022] Open
Abstract
Klebsiella pneumoniae is a Gram-negative, ubiquitous bacterium capable of causing severe nosocomial infections in individuals with impaired immune system. Emerging multi-drug resistant strains of this species and particularly carbapenem-resistant strains pose an urgent threat to public health. The lipopolysaccharide (LPS) O-antigen is the main surface antigen. It contributes to the virulence of this species and determines the O-serotype of K. pneumoniae isolates. Among the nine main O-serotypes of K. pneumoniae, O1-and O2-type pathogens are causative agents of over 50% of all infections. Serotype O1, the most common O-serotype, expresses complex LPS consisting of d-galactan-I (a polymer built of → 3)-β-d-Galf-(1 → 3)-α-d-Galp-(1 → repeating units) capped by d-galactan-II (built of [ → 3)-α-d-Galp-(1 → 3)-β-d-Galp-(1 →] repeating units). Galactan-I is present as the sole polymer in O2 serotype. Recently, in case of serotype O2, conversion of galactan-I to galactan-III (→ 3)-β-d-Galf-(1 → 3)-[α-d-Galp-(1 → 4)]-α-d-Galp-(1 →) was reported. Substitution of → 3)-α-d-Galp by a branching terminal α-d-Galp was dependent on the presence of the gmlABC operon and had a major impact on the antigenicity of the galactan polymer. Genetic analysis indicated that 40% of the O1 clinical isolates also carry the gmlABC locus; therefore we aimed to characterize the corresponding phenotype of LPS O-antigens. The presence of galactan-III among O1 strains was proven using galactan-III-specific monoclonal antibodies and confirmed by structural analyses performed using sugar and methylation analysis as well as classical and high-resolution magic angle spinning NMR spectroscopy. By using an isogenic mutant pair, we demonstrated that galactan-III expression was dependent on the presence of glycosyltransferases encoded by gmlABC, as was shown previously for the O2 serotype. Furthermore, the galactan-II structures in O1gml+ strains remained unaffected corroborating no functional interactions between the biosynthesis of galactan-III and galactan-II polymers.
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Affiliation(s)
- Katarina Stojkovic
- Laboratory of Microbial Immunochemistry and Vaccines, Department of Immunochemistry, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of SciencesWroclaw, Poland
| | | | - Marta Kaszowska
- Laboratory of Microbial Immunochemistry and Vaccines, Department of Immunochemistry, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of SciencesWroclaw, Poland
| | - Tomasz Niedziela
- Laboratory of Microbial Immunochemistry and Vaccines, Department of Immunochemistry, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of SciencesWroclaw, Poland
| | | | | | - Jolanta Lukasiewicz
- Laboratory of Microbial Immunochemistry and Vaccines, Department of Immunochemistry, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of SciencesWroclaw, Poland
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13
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Kelly R, Perry M, MacLean L, Whitfield C. Structures of the O-antigens of Klebsiella serotypes 02 (2a,2e), 02 (2a,2e,2h), and 02 (2a,2f,2g), members of a family of related D-galactan O-antigens in Klebsiella spp. ACTA ACUST UNITED AC 2016. [DOI: 10.1177/096805199500200208] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The structures of the lipopolysaccharide O-antigens from Klebsiella serotypes 02(2a,2f,2g), O2(2a,2e) and O2(2a,2e,2h) have been determined. These O-polysaccharides are part of a family of related structures, which share a D-galactan I backbone. D-galactan I has the repeating unit structure: [→3)-β-D-Gal f-(1→3)-α-D-Gal p-(1→]. The O-polysaccharide of serotype O2(2a,2f,2g) differs from other known O-polysaccharides in Klebsiella spp. Each of the main-chain Gal p residues in the 02(2a,2f,2g) O-polysaccharide is substituted with an α-(1→4)-linked D-Gal p residue, to form a trisaccharide repeating unit. The LPS O-polysaccharides of serotypes O2(2a,2e) and O2(2a,2e,2h) both contain α-(1→2)-linked D-Galp substituents on the main-chain Galp residues, and resemble serotype O9. The only difference between the 09, O2(2a,2e), and O2(2a,2e,2h) carbohydrate structures involves the stoichiometry of addition of side chain α-D-Gal p residues. However, the polymers from serotypes O2(2a,2e), O2(2a,2e,2h) and 09 are all modified by O-acetylation and these modifications may contribute to altered antigenic factors. The structures reported here resolve ambiguities between previous chemical and serological analyses of 02 antigens. Genetic analyses showed that enzymes involved in the addition of α-D-Gal p residues are encoded by genes outside the rfbO9 (O-antigen biosynthesis) region and this provides an explanation for occasional non-stoichiometric addition of side chain α-D-Galp residues.
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Affiliation(s)
- R.F. Kelly
- Canadian Bacterial Diseases Network, Department of Microbiology, University of Guelph, Guelph, Ontario, Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, Canada
| | - M.B. Perry
- Canadian Bacterial Diseases Network, Department of Microbiology, University of Guelph, Guelph, Ontario, Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, Canada
| | - L.L. MacLean
- Canadian Bacterial Diseases Network, Department of Microbiology, University of Guelph, Guelph, Ontario, Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, Canada
| | - C. Whitfield
- Canadian Bacterial Diseases Network, Department of Microbiology, University of Guelph, Guelph, Ontario, Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, Canada
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14
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Pantophlet R, Brade L, Brade H. Detection of lipid A by monoclonal antibodies in S-form lipopolysaccharide after acidic treatment of immobilized LPS on Western blot. ACTA ACUST UNITED AC 2016. [DOI: 10.1177/096805199700400202] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Lipopolysaccharides (LPSs) were separated by SDS-PAGE, transferred onto polyvinylidene difluoride membranes, and hydrolyzed under acid conditions known to liberate lipid A from a broad variety of bacterial species. Independent of whether bis- or monophosphorylated lipid was set free, it remained bound to the membrane during subsequent immunostaining with monoclonal antibodies (MAbs) specific for the 1,4'-bis- or 4'-monophosphorylated lipid A backbone. Lipid A could be detected in the smooth (S)-form LPS from Enterobacteriaceae (Salmonella enterica, Citrobacter, Escherichia coli, Klebsiella pneumoniae, Serratia marcescens and Yersinia enterocolitica) , Pseudomonas aeruginosa, Chromobacterium violaceum, Acinetobacter, Vibrio cholerae and Legionella pneumophila, thus allowing LPS-phenotype determination. The procedure can be used for the majority of Gram-negative bacteria, since LPSs containing 2,3-diamino-2,3-dideoxy-glucose or glucosamine in the lipid A disaccharide backbone could be detected. It was shown to be sensitive (up to 20 ng of hydrolyzed LPS could be detected), and could be easily performed using isolated LPS or whole-cell lysates with or without prior digestion with proteinase K. In addition to opening several other application possibilities, the procedure may be particularly useful in cases where silver-staining of the O-chain in SDSpolyacrylamide gels fails and specific antibodies against the O-antigen are not available.
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Affiliation(s)
- R. Pantophlet
- Division of Medical and Biochemical Microbiology, Research Center Borstel, Center for Medicine and Biosciences, Germany
| | - L. Brade
- Division of Medical and Biochemical Microbiology, Research Center Borstel, Center for Medicine and Biosciences, Germany
| | - H. Brade
- Division of Medical and Biochemical Microbiology, Research Center Borstel, Center for Medicine and Biosciences, Germany
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15
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Szijártó V, Guachalla LM, Hartl K, Varga C, Banerjee P, Stojkovic K, Kaszowska M, Nagy E, Lukasiewicz J, Nagy G. Both clades of the epidemic KPC-producing Klebsiella pneumoniae clone ST258 share a modified galactan O-antigen type. Int J Med Microbiol 2016; 306:89-98. [DOI: 10.1016/j.ijmm.2015.12.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 11/30/2015] [Accepted: 12/13/2015] [Indexed: 11/28/2022] Open
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16
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Rapid and Accurate Determination of Lipopolysaccharide O-Antigen Types in Klebsiella pneumoniae with a Novel PCR-Based O-Genotyping Method. J Clin Microbiol 2015; 54:666-75. [PMID: 26719438 DOI: 10.1128/jcm.02494-15] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 12/25/2015] [Indexed: 01/15/2023] Open
Abstract
Klebsiella pneumoniae, a Gram-negative bacillus that causes life-threatening infections in both hospitalized patients and ambulatory persons, can be classified into nine lipopolysaccharide (LPS) O-antigen serotypes. The O-antigen type has important clinical and epidemiological significance. However, K. pneumoniae O serotyping is cumbersome, and the reagents are not commercially available. To overcome the limitations of conventional serotyping methods, we aimed to create a rapid and accurate PCR method for K. pneumoniae O genotyping. We sequenced the genetic determinants of LPS O antigen from serotypes O1, O2a, O2ac, O3, O4, O5, O8, O9, and O12. We established a two-step genotyping scheme, based on the two genomic regions associated with O-antigen biosynthesis. The first set of PCR primers, which detects alleles at the wzm-wzt loci of the wb gene cluster, distinguishes between O1/O2, O3, O4, O5, O8, O9, and O12. The second set of PCR primers, which detects alleles at the wbbY region, further differentiates between O1, O2a, and O2ac. We verified the specificity of O genotyping against the O-serotype reference strains. We then tested the sensitivity and specificity of O genotyping in K. pneumoniae, using the 56 K-serotype reference strains with known O serotypes determined by an inhibition enzyme-linked immunosorbent assay (iELISA). There is a very good correlation between the O genotypes and classical O serotypes. Three discrepancies were observed and resolved by nucleotide sequencing--all in favor of O genotyping. The PCR-based O genotyping, which can be easily performed in clinical and research microbiology laboratories, is a rapid and accurate method for determining the LPS O-antigen types of K. pneumoniae isolates.
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17
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Cooper CA, Mainprize IL, Nickerson NN. Genetic, Biochemical, and Structural Analyses of Bacterial Surface Polysaccharides. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 883:295-315. [PMID: 26621474 DOI: 10.1007/978-3-319-23603-2_16] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Surface polysaccharides are an often essential component of the outer surface of bacteria. They may serve to protect organisms from harsh environmental conditions and to increase virulence. The focus of this review will be to introduce polysaccharide biosynthesis and export from the cell, and the associated techniques used to determine these glycostructures. Protein interactions and proteomics will then be discussed while introducing systems biology approaches used to determine protein-protein and protein-polysaccharide interactions. The final section will address related screening methods used to study gene regulation in bacteria relating to polysaccharide gene clusters and their associated regulators. The goal of this review will be to highlight key studies that have increased our knowledge of glycobiology and discuss novel methods that examine this field at the cellular level using systems biology.
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Affiliation(s)
- Colin A Cooper
- Agriculture and Food Laboratory, Laboratory Services, University of Guelph, 95 Stone Rd. W., Guelph, ON, N1H 8J7, Canada.
| | - Iain L Mainprize
- Department of Molecular and Cellular Biology, University of Guelph, 95 Stone Road, Guelph, ON, N1H 8J7, Canada
| | - Nicholas N Nickerson
- Department of Molecular and Cellular Biology, University of Guelph, 95 Stone Road, Guelph, ON, N1H 8J7, Canada.,Department of Infectious Diseases, Genentech Inc., South San Francisco, CA, 94080, USA
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18
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Hsieh PF, Wu MC, Yang FL, Chen CT, Lou TC, Chen YY, Wu SH, Sheu JC, Wang JT. D-galactan II is an immunodominant antigen in O1 lipopolysaccharide and affects virulence in Klebsiella pneumoniae: implication in vaccine design. Front Microbiol 2014; 5:608. [PMID: 25477867 PMCID: PMC4237132 DOI: 10.3389/fmicb.2014.00608] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 10/24/2014] [Indexed: 01/07/2023] Open
Abstract
In the O1 strain of Klebsiella, the lipopolysaccharide (LPS) O-antigen is composed of D-galactan I and D-galactan II. Although the composition of the O1 antigen of Klebsiella was resolved more than two decades, the genetic locus involved in the biosynthesis of D-galactan II and the role of D-galactan II in bacterial pathogenesis remain unclear. Here, we report the identification of the D-galactan II-synthesizing genes by screening a transposon mutant library of an acapsulated Klebsiella pneumoniae O1 strain with bacteriophage. K. pneumoniae strain deleted for wbbY exhibited abrogated D-galactan II production; altered serum resistance and attenuation of virulence. Serologic analysis of K. pneumoniae clinical isolates demonstrated that D-galactan II was more prevalent in community-acquired pyogenic liver abscess (PLA)—causing strains than in non-tissue-invasive strains. WbbY homologs, WbbZ homologs, and lipopolysaccharide structures based on D-galactan II also were present in several Gram-negative bacteria. Immunization of mice with the magA-mutant (K−1 O1) (that is, with a LPS D-galactan II-producing strain) provided protection against infection with an O1:K2 PLA strain. Our findings indicate that both WbbY and WbbZ homologs are sufficient for the synthesis of D-galactan II. D-galactan II represents an immunodominant antigen; is conserved among multiple species of Gram-negative bacteria and could be a useful vaccine candidate.
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Affiliation(s)
- Pei-Fang Hsieh
- Department of Microbiology, National Taiwan University College of Medicine Taipei, Taiwan
| | - Meng-Chuan Wu
- Department of Internal Medicine, National Taiwan University Hospital Taipei, Taiwan
| | - Feng-Ling Yang
- The Institute of Biological Chemistry, Academia Sinica Taipei, Taiwan
| | - Chun-Tang Chen
- Department of Microbiology, National Taiwan University College of Medicine Taipei, Taiwan
| | - Tzu-Chi Lou
- The Institute of Biological Chemistry, Academia Sinica Taipei, Taiwan
| | - Yi-Yin Chen
- Department of Microbiology, National Taiwan University College of Medicine Taipei, Taiwan
| | - Shih-Hsiung Wu
- The Institute of Biological Chemistry, Academia Sinica Taipei, Taiwan
| | - Jin-Chuan Sheu
- Department of Internal Medicine, National Taiwan University Hospital Taipei, Taiwan
| | - Jin-Town Wang
- Department of Microbiology, National Taiwan University College of Medicine Taipei, Taiwan ; Department of Internal Medicine, National Taiwan University Hospital Taipei, Taiwan
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19
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Shon AS, Bajwa RPS, Russo TA. Hypervirulent (hypermucoviscous) Klebsiella pneumoniae: a new and dangerous breed. Virulence 2013; 4:107-18. [PMID: 23302790 PMCID: PMC3654609 DOI: 10.4161/viru.22718] [Citation(s) in RCA: 716] [Impact Index Per Article: 65.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
A new hypervirulent (hypermucoviscous) variant of Klebsiella pneumoniae has emerged. First described in the Asian Pacific Rim, it now increasingly recognized in Western countries. Defining clinical features are the ability to cause serious, life-threatening community-acquired infection in younger healthy hosts, including liver abscess, pneumonia, meningitis and endophthalmitis and the ability to metastatically spread, an unusual feature for enteric Gram-negative bacilli in the non-immunocompromised. Despite infecting a healthier population, significant morbidity and mortality occurs. Although epidemiologic features are still being defined, colonization, particularly intestinal colonization, appears to be a critical step leading to infection. However the route of entry remains unclear. The majority of cases described to date are in Asians, raising the issue of a genetic predisposition vs. geospecific strain acquisition. The traits that enhance its virulence when compared with “classical” K. pneumoniae are the ability to more efficiently acquire iron and perhaps an increase in capsule production, which confers the hypermucoviscous phenotype. An objective diagnostic test suitable for routine use in the clinical microbiology laboratory is needed. If/when these strains become increasingly resistant to antimicrobials, we will be faced with a frightening clinical scenario.
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Affiliation(s)
- Alyssa S Shon
- Department of Medicine, University at Buffalo-State University of New York, Buffalo, NY, USA
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20
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Greenfield LK, Whitfield C. Synthesis of lipopolysaccharide O-antigens by ABC transporter-dependent pathways. Carbohydr Res 2012; 356:12-24. [PMID: 22475157 DOI: 10.1016/j.carres.2012.02.027] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Revised: 02/23/2012] [Accepted: 02/24/2012] [Indexed: 01/10/2023]
Abstract
The O-polysaccharide (O-PS; O-antigen) of bacterial lipopolysaccharides is made up of repeating units of one or more sugar residues and displays remarkable structural diversity. Despite the structural variations, there are only three strategies for O-PS assembly. The ATP-binding cassette (ABC)-transporter-dependent mechanism of O-PS biosynthesis is widespread. The Escherichia coli O9a and Klebsiella pneumoniae O2a antigens provide prototypes, which are distinguished by the fine details that link glycan polymerization and chain termination at the cytoplasmic face of the inner membrane to its export via the ABC transporter. Here, we describe the current understanding of these processes. Since glycoconjugate assembly complexes that utilize an ABC transporter-dependent pathway are widespread among the bacterial kingdom, the models described here are expected to extend beyond O-PS biosynthesis systems.
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Affiliation(s)
- Laura K Greenfield
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
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21
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Abstract
Complex glycoconjugates play critical roles in the biology of microorganisms. Despite the remarkable diversity in glycan structures and the bacteria that produce them, conserved themes are evident in the biosynthesis-export pathways. One of the primary pathways involves representatives of the ATP-binding cassette (ABC) transporter superfamily. These proteins are responsible for the export of a wide variety of cell surface oligo- and polysaccharides in both Gram-positive and Gram-negative bacteria. Recent investigations of the structure and function of ABC transporters involved in the export of lipopolysaccharide O antigens have revealed two fundamentally different strategies for coupling glycan polymerization to export. These mechanisms are distinguished by the presence (or absence) of characteristic nonreducing terminal modifications on the export substrates, which serve as chain termination and/or export signals, and by the presence (or absence) of a discrete substrate-binding domain in the nucleotide-binding domain polypeptide of the ABC transporter. A bioinformatic survey examining ABC exporters from known oligo- and polysaccharide biosynthesis loci identifies conserved nucleotide-binding domain protein families that correlate well with themes in the structures and assembly of glycans. The familial relationships among the ABC exporters generate hypotheses concerning the biosynthesis of structurally diverse oligo- and polysaccharides, which play important roles in the biology of bacteria with different lifestyles.
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22
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Banoub JH, El Aneed A, Cohen AM, Joly N. Structural investigation of bacterial lipopolysaccharides by mass spectrometry and tandem mass spectrometry. MASS SPECTROMETRY REVIEWS 2010; 29:606-650. [PMID: 20589944 DOI: 10.1002/mas.20258] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Mass spectrometric studies are now playing a leading role in the elucidation of lipopolysaccharide (LPS) structures through the characterization of antigenic polysaccharides, core oligosaccharides and lipid A components including LPS genetic modifications. The conventional MS and MS/MS analyses together with CID fragmentation provide additional structural information complementary to the previous analytical experiments, and thus contribute to an integrated strategy for the simultaneous characterization and correct sequencing of the carbohydrate moiety.
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Affiliation(s)
- Joseph H Banoub
- Fisheries and Oceans Canada, Science Branch, Special Projects, P.O. Box 5667, St. John's, Newfoundland, Canada A1C 5X1.
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23
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Kos V, Whitfield C. A membrane-located glycosyltransferase complex required for biosynthesis of the D-galactan I lipopolysaccharide O antigen in Klebsiella pneumoniae. J Biol Chem 2010; 285:19668-87. [PMID: 20410291 DOI: 10.1074/jbc.m110.122598] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
D-galactan I is a polysaccharide with the disaccharide repeat unit structure [-->3-beta-D-Galf-(1-->3)-alpha-D-Galp-(1-->]. This glycan represents the lipopolysaccharide O antigen found in many Gram-negative bacteria, including several Klebsiella pneumoniae O serotypes. The polysaccharide is synthesized in the cytoplasm prior to its export via an ATP-binding cassette transporter. Sequence analysis predicts three galactosyltransferases in the D-galactan I genetic locus. They are WbbO (belonging to glycosyltransferase (GT) family 4), WbbM (GT-family 8), and WbbN (GT-family 2). The WbbO and WbbM proteins are each predicted to contain two domains, with the GT modules located toward their C termini. The N-terminal domains of WbbO and WbbM exhibit no similarity to proteins with known function. In vivo complementation assays suggest that all three glycosyltransferases are required for D-galactan I biosynthesis. Using a bacterial two-hybrid system and confirmatory co-purification strategies, evidence is provided for protein-protein interactions among the glycosyltransferases, creating a membrane-located enzyme complex dedicated to d-galactan I biosynthesis.
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Affiliation(s)
- Veronica Kos
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
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Vinogradov E, Frirdich E, MacLean LL, Perry MB, Petersen BO, Duus JØ, Whitfield C. Structures of lipopolysaccharides from Klebsiella pneumoniae. Eluicidation of the structure of the linkage region between core and polysaccharide O chain and identification of the residues at the non-reducing termini of the O chains. J Biol Chem 2002; 277:25070-81. [PMID: 11986326 DOI: 10.1074/jbc.m202683200] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Deamination of LPSs from Klebsiella pneumoniae released O-chain polysaccharides together with a fragment of the core oligosaccharide. The structures of the products from serotypes O1, O2a, O2a,c, O3, O4, O5, and O12 were determined by NMR spectroscopy and chemical methods, identifying the linkage region between the O antigens and the core as well as novel residues at the non-reducing ends of the polysaccharides. All serotypes had an identical linkage between the O chain and core.
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Affiliation(s)
- Evgeny Vinogradov
- Institute for Biological Sciences, National Research Council, Ottawa, Ontario K1A 0R6, Canada.
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25
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Abstract
Bacterial lipopolysaccharides (LPS) typically consist of a hydrophobic domain known as lipid A (or endotoxin), a nonrepeating "core" oligosaccharide, and a distal polysaccharide (or O-antigen). Recent genomic data have facilitated study of LPS assembly in diverse Gram-negative bacteria, many of which are human or plant pathogens, and have established the importance of lateral gene transfer in generating structural diversity of O-antigens. Many enzymes of lipid A biosynthesis like LpxC have been validated as targets for development of new antibiotics. Key genes for lipid A biosynthesis have unexpectedly also been found in higher plants, indicating that eukaryotic lipid A-like molecules may exist. Most significant has been the identification of the plasma membrane protein TLR4 as the lipid A signaling receptor of animal cells. TLR4 belongs to a family of innate immunity receptors that possess a large extracellular domain of leucine-rich repeats, a single trans-membrane segment, and a smaller cytoplasmic signaling region that engages the adaptor protein MyD88. The expanding knowledge of TLR4 specificity and its downstream signaling pathways should provide new opportunities for blocking inflammation associated with infection.
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Affiliation(s)
- Christian R H Raetz
- Department of Biochemistry, Duke University Medical Center, Durham, North Carolina 27710, USA.
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26
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Guan S, Clarke AJ, Whitfield C. Functional analysis of the galactosyltransferases required for biosynthesis of D-galactan I, a component of the lipopolysaccharide O1 antigen of Klebsiella pneumoniae. J Bacteriol 2001; 183:3318-27. [PMID: 11344139 PMCID: PMC99629 DOI: 10.1128/jb.183.11.3318-3327.2001] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
D-Galactan I is an O-antigenic polymer with the repeat unit structure [-->3)-beta-D-Galf-(1-->3)-alpha-D-Galp-(1-->], that is found in the lipopolysaccharide of Klebsiella pneumoniae O1 and other gram-negative bacteria. A genetic locus containing six genes is responsible for the synthesis and assembly of D-galactan I via an ATP-binding cassette (ABC) transporter-dependent pathway. The galactosyltransferase activities that are required for the processive polymerization of D-galactan I were identified by using in vitro reactions. The activities were determined with endogenous lipid acceptors in membrane preparations from Escherichia coli K-12 expressing individual enzymes (or combinations of enzymes) or in membranes reconstituted with specific lipid acceptors. The D-galactan I polymer is built on a lipid acceptor, undecaprenyl pyrophosphoryl-GlcpNAc, a product of the WecA enzyme that participates in the biosynthesis of enterobacterial common antigen and O-antigenic polysaccharide (O-PS) biosynthesis pathways. This intermediate is directed into D-galactan I biosynthesis by the bifunctional wbbO gene product, which sequentially adds one Galp and one Galf residue from the corresponding UDP-sugars to form a lipid-linked trisaccharide. The two galactosyltransferase activities of WbbO are separable by limiting the UDP-Galf precursor. Galactosyltransferase activity in membranes reconstituted with exogenous lipid-linked trisaccharide acceptor and the known structure of D-galactan I indicate that WbbM catalyzes the subsequent transfer of a single Galp residue to form a lipid-linked tetrasaccharide. Chain extension of the D-galactan I polymer requires WbbM for Galp transferase, together with Galf transferase activity provided by WbbO. Comparison of the biosynthetic pathways for D-galactan I and the polymannose E. coli O9a antigen reveals some interesting features that may reflect a common theme in ABC transporter-dependent O-PS assembly systems.
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Affiliation(s)
- S Guan
- Department of Microbiology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
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27
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Held TK, Jendrike NR, Rukavina T, Podschun R, Trautmann M. Binding to and opsonophagocytic activity of O-antigen-specific monoclonal antibodies against encapsulated and nonencapsulated Klebsiella pneumoniae serotype O1 strains. Infect Immun 2000; 68:2402-9. [PMID: 10768923 PMCID: PMC97438 DOI: 10.1128/iai.68.5.2402-2409.2000] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The high mortality of nosocomial infections caused by Klebsiella spp. has acted as a stimulus to develop immunotherapeutic approaches targeted against surface molecules of these bacteria. Since O-antigen-specific antibodies may add to the protective effect of K antisera, we tested the functional and binding capacity of O-antigen-specific monoclonal antibodies (MAbs) raised against different Klebsiella O antigens. The MAbs tested were specific for the O-polysaccharide partial antigens D-galactan II (MAb Ru-O1), D-galactan I (MAb IV/4-5), or core oligosaccharide (MAb V/9-5) of the Klebsiella serogroup O1 antigen. In enzyme-linked immunosorbent assay binding experiments, we found that all MAbs recognized their epitopes on intact capsule-free bacteria; however, binding to encapsulated wild-type strains belonging to different K-antigen serotypes was significantly reduced. The K2 antigen acted as the strongest penetration barrier, while the K7 and K21 antigens allowed some, though diminished, antibody binding. In vitro phagocytic killing experiments showed that MAb Ru-O1 possessed significant opsonizing activity for nonencapsulated O1 serogroup strains and also, to a much lesser extent, for encapsulated strains belonging to the O1:K7 and O1:K21 serotypes. MAbs or antisera specific for the D-galactan II antigen may thus be the most promising agents for further efforts to develop a second-generation Klebsiella hyperimmune globulin comprising both K- and O-antigen specificities.
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Affiliation(s)
- T K Held
- Department of Hematology and Oncology, Charité/Campus Virchow-Klinikum, Humboldt University, 13353 Berlin, Germany
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28
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Hansen DS, Mestre F, Alberti S, Hernández-Allés S, Alvarez D, Doménech-Sánchez A, Gil J, Merino S, Tomás JM, Benedí VJ. Klebsiella pneumoniae lipopolysaccharide O typing: revision of prototype strains and O-group distribution among clinical isolates from different sources and countries. J Clin Microbiol 1999; 37:56-62. [PMID: 9854064 PMCID: PMC84167 DOI: 10.1128/jcm.37.1.56-62.1999] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/1998] [Accepted: 10/19/1998] [Indexed: 11/20/2022] Open
Abstract
We have previously described an inhibition enzyme-linked immunosorbent assay method for the O typing of O1 lipopolysaccharide from Klebsiella pneumoniae which overcomes the technical problems and limitations of the classical O-typing method. In this study, we have extended the method to all of the currently recognized O types. The method was validated by studying the prototype strains that have defined the O groups by the classical tube agglutinatination O-typing method. Based on these results, we confirmed the O types of 60 of 64 typeable strains, and we propose a revised O-antigenic scheme, with minor but necessary changes, consisting of serogroups or serotypes O1, O2, O2ac, O3, O4, O5, O7, O8, and O12. Application of this typing method to 638 K. pneumoniae clinical isolates from Denmark, Spain, and the United States from different sources (blood, urine, and others) showed that up to 80% of these isolates belong to serotypes or serogroups O1, O2, O3, and O5, independently of the source of isolation, and that a major group of nontypeable isolates, representing about 17% of the total, consists of half O+ and half O- strains. Differences were observed, however, in the prevalence of the lipopolysaccharide O types or groups, depending on the country and isolation source.
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Affiliation(s)
- D S Hansen
- The International Escherichia and Klebsiella Reference Centre (WHO), Statens Serum Institut, and Department of Clinical Microbiology, Hvidovre Hospital, Copenhagen, Denmark
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29
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Trautmann M, Ruhnke M, Rukavina T, Held TK, Cross AS, Marre R, Whitfield C. O-antigen seroepidemiology of Klebsiella clinical isolates and implications for immunoprophylaxis of Klebsiella infections. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 1997; 4:550-5. [PMID: 9302204 PMCID: PMC170594 DOI: 10.1128/cdli.4.5.550-555.1997] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
To provide a database for the development of an O-antigen-polysaccharide-containing vaccine against Klebsiella spp., we examined the O-antigen seroepidemiology of 378 Klebsiella clinical isolates collected prospectively in two university centers. Strains were typed by competitive enzyme-linked immunosorbent assay with rabbit antisera specific for serogroups O1 to O12 and monoclonal antibodies (MAbs) specific for serogroups O1, O2ab, O2ac, and the genus-specific core antigen. The numbers of isolates (percentages) of individual O serogroups were as follows: 148 (39.2) for serogroup O1, 40 (10.6) for serogroup O2ab, 4 (1.1) for serogroup O2ac, 89 (23.6) for serogroup O3, 2 (0.5) for serogroup O4, 32 (8.5) for serogroup O5, none for serogroups O7, O9, and O12, and 21 (5.6) for serogroup O11. Forty-two (11.1) of the strains were non-O-typeable. O-serogroup distributions were virtually identical between isolates from invasive infections and those from noninvasive infections or colonizations. A vaccine containing the O-specific polysaccharides of serogroups O1, O2ab, O3, and O5 would cover 82% of clinically occurring O-antigen specificities. Three hundred thirty-eight of 378 isolates (89.4%) reacted with the genus-specific MAb V/9-5, which recognizes an epitope of the outer core region of Klebsiella lipopolysaccharide. Antibodies directed against this epitope may represent a further alternative for O-antigen-targeted immunoprophylaxis of Klebsiella infections. These data support further experimental investigations on the protective potential of O-antigen-based vaccines and/or hyperimmune globulins in Klebsiella infection.
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Affiliation(s)
- M Trautmann
- Department of Medical Microbiology and Hygiene, University of Ulm, Germany
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30
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Köplin R, Brisson JR, Whitfield C. UDP-galactofuranose precursor required for formation of the lipopolysaccharide O antigen of Klebsiella pneumoniae serotype O1 is synthesized by the product of the rfbDKPO1 gene. J Biol Chem 1997; 272:4121-8. [PMID: 9020123 DOI: 10.1074/jbc.272.7.4121] [Citation(s) in RCA: 104] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The O-side-chain polysaccharide in the lipopolysaccharide of Klebsiella pneumoniae O1 is based on a backbone structure of repeat units of [-->3)-beta-D-Galf-(1-->3)-alpha-D-Galp-(1-->]; this structure is termed D-galactan I. The rfb (O-antigen biosynthesis) gene cluster directs the synthesis of D-galactan I and consists of six genes termed rfbA-FKPO1. In this paper we show that rfbDKPO1 encodes a UDP-galactopyranose mutase (NAD(P)H-requiring) (EC 5.4.99. 9), which forms uridine 5'-(trihydrogen diphosphate) P'-alpha-D-galactofuranosyl ester (UDP-Galf), the biosynthetic precursor of galactofuranosyl residues. The deduced amino acid sequence of rfbDKPO1 shows 85% and 37.5% identity to the rfbDKPO8 gene of K. pneumoniae serotype O8 and the glf gene of Escherichia coli, respectively. The molecular mass of the purified RfbDKPO1 enzyme is 45 kDa as determined by SDS-polyacrylamide gel electrophoresis, while gel filtration revealed a molecular mass of 92 kDa, suggesting a dimeric structure for the native protein. The rfbDKPO1 gene product interconverts uridine 5'-(trihydrogen diphosphate) P'-alpha-D-galactopyranosyl ester (UDP-Galp) and UDP-Galf. Unlike Glf, RfbDKPO1 showed a requirement for NADH or NADPH, which could not be replaced by NAD or NADP. RfbDKPO1 was used to synthesize milligram quantities of UDP-Galf, allowing this compound to be purified and fully characterized in an intact form for the first time. The structure of UDP-Galf was proven by NMR spectroscopy.
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Affiliation(s)
- R Köplin
- Canadian Bacterial Diseases Network, University of Guelph, Guelph, Ontario, Canada, N1G 2W1
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31
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Kelly RF, Whitfield C. Clonally diverse rfb gene clusters are involved in expression of a family of related D-galactan O antigens in Klebsiella species. J Bacteriol 1996; 178:5205-14. [PMID: 8752339 PMCID: PMC178318 DOI: 10.1128/jb.178.17.5205-5214.1996] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Klebsiella species express a family of structurally related lipopolysaccharide O antigens which share a common backbone known as D-galactan I. Serotype specificity results from modification of D-galactan I by addition of domains of altered structure or by substitution with O-acetyl and/or alpha-D-Galp side groups with various linkages and stoichiometries. In the prototype, Klebsiella serotype O1, the his-linked rfb gene cluster is required for synthesis of D-galactan I, but genes conferring serotype specificity are unlinked. The D-galactan I part of the O polysaccharide is O acetylated in Klebsiella serotype O8. By cloning the rfb region from Klebsiella serotype O8 and analyzing the O polysaccharide synthesized in Escherichia coli K-12 hosts, we show that, like rfbO1, the rfbO8 region directs formation of unmodified D-galactan I. The rfbAB genes encode an ATP-binding cassette transporter required for export of polymeric D-galactan I across the plasma membrane prior to completion of the lipopolysaccharide molecule by ligation of the O polysaccharide to lipid A-core. Complementation experiments show that the rfbAB gene products in serotypes O1 and O8 are functionally equivalent and interchangeable. Hybridization experiments and physical mapping of the rfb regions in related Klebsiella serotypes suggest the existence of shared rfb genes with a common organization. However, despite the functional equivalence of these rfb gene clusters, at least three distinct clonal groups were detected in different Klebsiella species and subspecies, on the basis of Southern hybridization experiments carried out under high-stringency conditions. The clonal groups cannot be predicted by features of the O-antigen structure. To examine the relationships in more detail, the complete nucleotide sequence of the serotype O8 rfb cluster was determined and compared with that of the serotype O1 prototype. The nucleotide sequences for the six rfb genes showed variations in moles percent G+C values and in the values for nucleotide sequence identity, which ranged from 66.9 to 79.7%. The predicted polypeptides ranged from 64.3% identity (78.4% total similarity) to 94.3% identity (98.0% similarity). The results presented here are not consistent with dissemination of the Klebsiella D-galactan I rfb genes through recent lateral transfer events.
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Affiliation(s)
- R F Kelly
- Department of Microbiology, University of Guelph, Ontario, Canada
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32
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33
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Tone-Shimokawa Y, Toida T, Kawashima T. Isolation and structural analysis of polysaccharide containing galactofuranose from the cell walls of Bifidobacterium infantis. J Bacteriol 1996; 178:317-20. [PMID: 8550438 PMCID: PMC177659 DOI: 10.1128/jb.178.1.317-320.1996] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
We isolated cell wall polysaccharides (PS-1 and PS-2) from Bifidobacterium infantis Reuter ATCC 15697 and found that the backbone of PS-2 is-->3)-beta-D-Galf-(1-->3)-alpha-D-Galp- (1-->in which beta-D-Galf and alpha-D-Galp are partially substituted at O-6 with beta-D-Glcp. This is the first report of the presence of this disaccharide backbone in a gram-positive bacterium; it resembles the O antigen of some bacteria.
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Affiliation(s)
- Y Tone-Shimokawa
- Biochemical Research Laboratory, Morinaga Milk Industry Co., Ltd., Kanagawa, Japan
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34
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Clarke BR, Bronner D, Keenleyside WJ, Severn WB, Richards JC, Whitfield C. Role of Rfe and RfbF in the initiation of biosynthesis of D-galactan I, the lipopolysaccharide O antigen from Klebsiella pneumoniae serotype O1. J Bacteriol 1995; 177:5411-8. [PMID: 7559323 PMCID: PMC177345 DOI: 10.1128/jb.177.19.5411-5418.1995] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The 6.6-kb rfb gene cluster from Klebsiella pneumoniae serotype O1 (rfbKpO1) contains six genes whose products are required for the biosynthesis of a lipopolysaccharide O antigen with the following repeating unit structure: -->3-beta-D-Galf-1-->3-alpha-D-Galp-1-->(D-galactan I). rfbFKpO1 is the last gene in the cluster, and its gene product is required for the initiation of D-galactan I synthesis. Escherichia coli K-12 strains expressing the RfbFKpO1 polypeptide contain dual galactopyranosyl and galactofuranosyl transferase activity. This activity modifies the host lipopolysaccharide core by adding the disaccharide beta-D-Galf-1-->3-alpha-D-Galp, representing a single repeating unit of D-galactan I. The formation of the lipopolysaccharide substituted either with the disaccharide or with authentic polymeric D-galactan I is dependent on the activity of the Rfe enzyme. Rfe (UDP-GlcpNAc::undecaprenylphosphate GlcpNAc-1-phosphate transferase) catalyzes the formation of the lipid-linked biosynthetic intermediate to which galactosyl residues are transferred during the initial steps of D-galactan I synthesis. The rfbFKpO1 gene comprises 1,131 nucleotides, and the predicted polypeptide consists of 373 amino acid residues with a predicted M(r) of 42,600. A polypeptide with an M(r) of 42,000 was evident in sodium dodecyl sulfate-polyacrylamide gels when rfbKpO1 was expressed behind the T7 promoter. The carboxy-terminal region of RfbFKpO1 shares similarity with the carboxy terminus of RfpB, a galactopyranosyl transferase which is involved in the synthesis of the type 1 O antigen of Shigella dysenteriae.
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Affiliation(s)
- B R Clarke
- Department of Microbiology, University of Guelph, Ontario, Canada
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35
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Süsskind M, Müller-Loennies S, Nimmich W, Brade H, Holst O. Structural investigation on the carbohydrate backbone of the lipopolysaccharide from Klebsiella pneumoniae rough mutant R20/O1-. Carbohydr Res 1995; 269:C1-7. [PMID: 7773983 DOI: 10.1016/0008-6215(95)00002-b] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- M Süsskind
- Biochemische Mikrobiologie, Forschungsinstitut Borstel, Institut für Experimentelle Biologie und Medizin, Germany
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36
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Szabo M, Bronner D, Whitfield C. Relationships between rfb gene clusters required for biosynthesis of identical D-galactose-containing O antigens in Klebsiella pneumoniae serotype O1 and Serratia marcescens serotype O16. J Bacteriol 1995; 177:1544-53. [PMID: 7533758 PMCID: PMC176771 DOI: 10.1128/jb.177.6.1544-1553.1995] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The lipopolysaccharide O antigens of Klebsiella pneumoniae serotype O1 and Serratia marcescens serotype O16 both contain a repeating unit disaccharide of [-->3)-beta-D-Galf-(1-->3)-alpha-D-Galp-(1-->]; the resulting polymer is known as D-galactan I. In K. pneumoniae serotype O1, the genes responsible for the synthesis of D-galactan I are found in the rfb gene cluster (rfbKpO1). We report here the cloning and analysis of the rfb cluster from S. marcescens serotype O16 (rfbSmO16). This is the first rfb gene cluster examined for the genus Serratia. Synthesis of D-galactan I is an rfe-dependent process for both K. pneumoniae serotype O1 and S. marcescens serotype O16. Hybridization experiments with probes derived from each of the six rfbKpO1 genes indicate that the cloned rfbSmO16 cluster contains homologous genes arranged in the same order. However, the degree of homology at the nucleotide sequence level was sufficiently low that hybridization was detected only under low-stringency conditions. rfbABSmO16 genes were subcloned and shown to encode an ABC-2 (ATP-binding cassette) transporter which is functionally identical to the one encoded by the corresponding rfb genes from K. pneumoniae serotype O1. The amino acid sequences of the predicted RfbA and RfbB homologs showed identities of 75.7% (87.9% total similarity) and 78.0% (86.5% total similarity), respectively. The last gene of the rfbKpO1 cluster, rfbFKpO1, encodes a bifunctional galactosyltransferase which initiates the formation of D-galactan I. RfbFKpO1 and RfbFSmO16 are 57.6% identical (with 71.1% total similarity), and both show similarity with RfpB, the galactosyltransferase involved in the synthesis of Shigella dysenteriae type I O-polysaccharide. The G+C contents of the rfbAB genes from each organism are quite similar, and values are lower than those typical for the species. However, the G+C content of rfbFSmO16 (47.6%) was much higher than that of rfbFKpO1 (37.3%), despite the fact that the average for each species (52 to 60%) falls within the same range.
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MESH Headings
- ATP-Binding Cassette Transporters/metabolism
- Amino Acid Sequence
- Antigens, Bacterial/biosynthesis
- Antigens, Bacterial/chemistry
- Antigens, Bacterial/genetics
- Antigens, Bacterial/immunology
- Base Composition
- Base Sequence
- Biological Transport
- Carbohydrate Sequence
- Cloning, Molecular
- Enterobacteriaceae/classification
- Enterobacteriaceae/genetics
- Enterobacteriaceae/immunology
- Galactans/biosynthesis
- Galactans/chemistry
- Galactans/genetics
- Galactans/immunology
- Galactose/analysis
- Galactose/genetics
- Galactose/immunology
- Genes, Bacterial/genetics
- Klebsiella pneumoniae/classification
- Klebsiella pneumoniae/genetics
- Klebsiella pneumoniae/immunology
- Lipopolysaccharides/chemistry
- Molecular Sequence Data
- Multigene Family/genetics
- Nucleic Acid Hybridization
- O Antigens
- Polysaccharides, Bacterial/biosynthesis
- Polysaccharides, Bacterial/chemistry
- Polysaccharides, Bacterial/genetics
- Polysaccharides, Bacterial/immunology
- Sequence Homology, Amino Acid
- Serotyping
- Serratia marcescens/classification
- Serratia marcescens/genetics
- Serratia marcescens/immunology
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Affiliation(s)
- M Szabo
- Canadian Bacterial Diseases Network, Department of Microbiology, University of Guelph, Ontario, Canada
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37
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Bronner D, Clarke BR, Whitfield C. Identification of an ATP-binding cassette transport system required for translocation of lipopolysaccharide O-antigen side-chains across the cytoplasmic membrane of Klebsiella pneumoniae serotype O1. Mol Microbiol 1994; 14:505-19. [PMID: 7533882 DOI: 10.1111/j.1365-2958.1994.tb02185.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The rfbKpO1 gene cluster of Klebsiella pneumoniae O1 directs synthesis of the D-galactan I component of the lipopolysaccharide O-antigen. The first two genes in the rfbKpO1 cluster encode RfbAKpO1 and RfbBKpO1, with predicted sizes of 29.5 or 30.0 kDa and 27.4 kDa, respectively. RfbBKpO1 contains a consensus ATP-binding domain and shares homology with several proteins which function as ATP-binding components of cell surface polysaccharide transporters. RfbAKpO1 is predicted to be an integral membrane protein with five putative membrane-spanning domains and its transmembrane topology was confirmed by TnphoA mutagenesis. The hydropathy plot of RfbAKpO1 resembles KpsM, the transcytoplasmic membrane component of the capsular polysaccharide transporter from Escherichia coli K-1 and K-5. These relationships suggest that RfbAKpO1 and RfbBKpO1 belong to a family of two-component ABC (ATP-binding cassette) transporters. E. coli K-12 containing a plasmid carrying an rfbKpO1 gene cluster deleted in rfbAKpO1 and rfbBKpO1 expresses rough lipopolysaccharide molecules on its surface and accumulates cytoplasmic O-antigen. When RfbAKpO1 and RfbBKpO1 are supplied in trans by a compatible plasmid, O-polysaccharide transport is restored and smooth D-galactan I-substituted lipopolysaccharide is produced. RfbAKpO1 and RfbBKpO1 are, therefore, proposed to constitute a system required for transport of D-galactan I across the cytoplasmic membrane, where RfbAKpO1 represents the membrane-spanning translocator and RfbBKpO1 couples the energy of ATP hydrolysis ot the transport process.
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Affiliation(s)
- D Bronner
- Department of Microbiology, University of Guelph, Ontario, Canada
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38
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Lukácová M, Baumann M, Brade L, Mamat U, Brade H. Lipopolysaccharide smooth-rough phase variation in bacteria of the genus Chlamydia. Infect Immun 1994; 62:2270-6. [PMID: 8188348 PMCID: PMC186507 DOI: 10.1128/iai.62.6.2270-2276.1994] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
In two strains of Chlamydia psittaci and in Chlamydia trachomatis serotype L1, we have detected a so-far-unknown antigen which (i) is resistant to heat and proteolytic digestion, (ii) can be extracted with phenol-water into the water phase, (iii) gives a ladder-like banding pattern in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, (iv) is immunogenic in rabbits and mice, and (v) contains immunoreactivity of lipid A, a common and characteristic component of gram-negative lipopolysaccharides (LPS). Thus, chlamydiae contain, in addition to the known rough-type LPS, another LPS type which is phenotypically smooth (S-LPS). S-LPS was observed preferentially in chlamydiae grown in the yolk sac of embryonated eggs; it was, however, also detected by immunofluorescence in tissue culture-grown chlamydiae with a monoclonal antibody against S-LPS.
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Affiliation(s)
- M Lukácová
- Division of Biochemical Microbiology, Forschungsinstitut Borstel, Institut für Experimentelle Biologie und Medizin, Germany
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39
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Trautmann M, Vogt K, Hammack C, Cross AS. A murine monoclonal antibody defines a unique epitope shared by Klebsiella lipopolysaccharides. Infect Immun 1994; 62:1282-8. [PMID: 7510667 PMCID: PMC186270 DOI: 10.1128/iai.62.4.1282-1288.1994] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
A hybridoma secreting a monoclonal antibody (MAb) directed against Klebsiella lipopolysaccharide (LPS) was derived from spleen cells of mice immunized a smooth, nonencapsulated Klebsiella strain (Friedländer 201; serogroup O1). The MAb, called V/9-5 (immunoglobulin G2a), cross-reacted with LPS preparations produced from reference strains for the Klebsiella O serogroups O1, O2ab, O2ac, O3, O4, O5, and O12. Furthermore, the MAb reacted with LPSs from serogroup reference strains O6/O8, O9, and O11, which are regarded as being identical to O1, O2, and O4, respectively. When testing the supernatant of clinically isolated Klebsiella strains by means of an inhibition enzyme-linked immunosorbent assay, we found that 86 (92.4%) of 93 Klebsiella pneumoniae subsp. pneumoniae isolates and 24 (96.0%) of 25 K. oxytoca isolates harbored the cross-reactive epitope. By contrast, two laboratory strains of K. pneumoniae subsp. rhinoscleromatis did not react with MAb V/9-5. The MAb proved to be specific for the genus Klebsiella, since it did not react with any of a total of 73 strains belonging to other gram-negative bacterial genera. In conjunction with other LPS-specific MAbs, MAb V/9-5 might become a useful reagent for rapid identification of klebsiellae in clinical specimens. Furthermore, the epitope recognized by MAb V/9-5 might serve as a target epitope for the production of human MAbs for immunotherapeutic purposes.
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Affiliation(s)
- M Trautmann
- Department of Bacteriology, University of Ulm, Federal Republic of Germany
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Hancock RE, Karunaratne DN, Bernegger-Egli C. Chapter 12 Molecular organization and structural role of outer membrane macromolecules. BACTERIAL CELL WALL 1994. [DOI: 10.1016/s0167-7306(08)60415-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Kelly RF, Severn WB, Richards JC, Perry MB, MacLean LL, Tomás JM, Merino S, Whitfield C. Structural variation in the O-specific polysaccharides of Klebsiella pneumoniae serotype O1 and O8 lipopolysaccharide: evidence for clonal diversity in rfb genes. Mol Microbiol 1993; 10:615-25. [PMID: 7526122 DOI: 10.1111/j.1365-2958.1993.tb00933.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The O-polysaccharide fraction of the lipopolysaccharide from Klebsiella pneumoniae serotype O8 was found to comprise two galactose-containing homopolymers. Structural analysis, using chemical and high-field nuclear magnetic resonance (NMR) techniques, established that the K. pneumoniae O8 polysaccharides are composed of the linear, disaccharide repeating units [formula: see text] K. pneumoniae O8 mutant RFK-1 was isolated by resistance to phage KO1-2; strain RFK-1 expressed only D-galactan I-OAc. The 1H- and 13C-NMR resonances from this O-polysaccharide indicate that all of the O-acetyl groups within the K. pneumoniae O8 polysaccharide are carried on D-galactan I and O-acetylation occurs only on the beta-D-galactofuranose residues; 60% of the available beta-D-galactofuranose residues are non-acetylated. The O-acetylation of the remaining residues is equally distributed between the O-2 and O-6 positions. The carbohydrate backbone structures in the O8 polysaccharide are identical to D-galactan I and II expressed by K. pneumoniae O1, accounting for the antigenic cross-reaction between strains belonging to serotypes O1 and O8. However, the O1 polysaccharides are not acetylated and the O-acetyl groups present in the K. pneumoniae serotype O8 polysaccharides provide a structural basis for their recognition as distinct serotypes. The rfb (O-polysaccharide biosynthesis) gene cluster of K. pneumoniae serotype O1 determines the synthesis of D-galactan I. rfbKpO1-specific gene probes were used to examine conservation in the rfb gene clusters of other K. pneumoniae serotypes which produce D-galactan I. Six O1 strains were examined and all showed hybridization with rfbKpO1 probes under conditions of high stringency. Three serotype O2 strains produce D-galactan I and these strains also contained DNA sequences recognized by rfbKpO1 probes under high stringency. The physical maps of these homologous rfb chromosomal regions showed some polymorphism. Surprisingly, the rfbKpO8 region from K. pneumoniae serotype O8 was only recognized by rfbKpO1 probes under low-stringency hybridization conditions, providing evidence for two substantially different clonal groups of rfb genes from K. pneumoniae strains with structurally related O-antigens.
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Affiliation(s)
- R F Kelly
- Department of Microbiology, University of Guelph, Ontario, Canada
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MacLean LL, Whitfield C, Perry MB. Characterization of the polysaccharide antigen of Klebsiella pneumoniae O:9 lipopolysaccharide. Carbohydr Res 1993; 239:325-8. [PMID: 7681358 DOI: 10.1016/0008-6215(93)84231-t] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- L L MacLean
- Canadian Bacterial Diseases Network, Institute for Biological Sciences, National Research Council, Ottawa, Ontario
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Whitfield C, Valvano MA. Biosynthesis and expression of cell-surface polysaccharides in gram-negative bacteria. Adv Microb Physiol 1993; 35:135-246. [PMID: 8310880 DOI: 10.1016/s0065-2911(08)60099-5] [Citation(s) in RCA: 176] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- C Whitfield
- Department of Microbiology, University of Guelph, Ontario, Canada
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