1
|
Hong Y, Hu D, Verderosa AD, Qin J, Totsika M, Reeves PR. Repeat-Unit Elongations To Produce Bacterial Complex Long Polysaccharide Chains, an O-Antigen Perspective. EcoSal Plus 2023; 11:eesp00202022. [PMID: 36622162 PMCID: PMC10729934 DOI: 10.1128/ecosalplus.esp-0020-2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 12/02/2022] [Indexed: 01/10/2023]
Abstract
The O-antigen, a long polysaccharide that constitutes the distal part of the outer membrane-anchored lipopolysaccharide, is one of the critical components in the protective outer membrane of Gram-negative bacteria. Most species produce one of the structurally diverse O-antigens, with nearly all the polysaccharide components having complex structures made by the Wzx/Wzy pathway. This pathway produces repeat-units of mostly 3-8 sugars on the cytosolic face of the cytoplasmic membrane that is translocated by Wzx flippase to the periplasmic face and polymerized by Wzy polymerase to give long-chain polysaccharides. The Wzy polymerase is a highly diverse integral membrane protein typically containing 10-14 transmembrane segments. Biochemical evidence confirmed that Wzy polymerase is the sole driver of polymerization, and recent progress also began to demystify its interacting partner, Wzz, shedding some light to speculate how the proteins may operate together during polysaccharide biogenesis. However, our knowledge of how the highly variable Wzy proteins work as part of the O-antigen processing machinery remains poor. Here, we discuss the progress to the current understanding of repeat-unit polymerization and propose an updated model to explain the formation of additional short chain O-antigen polymers found in the lipopolysaccharide of diverse Gram-negative species and their importance in the biosynthetic process.
Collapse
Affiliation(s)
- Yaoqin Hong
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
- School of Life and Environmental Sciences, The University of Sydney, Camperdown, New South Wales, Australia
| | - Dalong Hu
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
| | - Anthony D. Verderosa
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Jilong Qin
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Makrina Totsika
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Peter R. Reeves
- School of Life and Environmental Sciences, The University of Sydney, Camperdown, New South Wales, Australia
| |
Collapse
|
2
|
Wiseman B, Widmalm G, Högbom M. Alternating L4 loop architecture of the bacterial polysaccharide co-polymerase WzzE. Commun Biol 2023; 6:802. [PMID: 37532793 PMCID: PMC10397196 DOI: 10.1038/s42003-023-05157-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 07/19/2023] [Indexed: 08/04/2023] Open
Abstract
Lipopolysaccharides such as the enterobacterial common antigen are important components of the enterobacterial cell envelope that act as a protective barrier against the environment and are often polymerized by the inner membrane bound Wzy-dependent pathway. By employing cryo-electron microscopy we show that WzzE, the co-polymerase component of this pathway that is responsible for the length modulation of the enterobacterial common antigen, is octameric with alternating up-down conformations of its L4 loops. The alternating up-down nature of these essential loops, located at the top of the periplasmic bell, are modulated by clashing helical faces between adjacent protomers that flank the L4 loops around the octameric periplasmic bell. This alternating arrangement and a highly negatively charged binding face create a dynamic environment in which the polysaccharide chain is extended, and suggest a ratchet-type mechanism for polysaccharide elongation.
Collapse
Affiliation(s)
- Benjamin Wiseman
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden.
| | - Göran Widmalm
- Department of Organic Chemistry, Stockholm University, Stockholm, Sweden
| | - Martin Högbom
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden.
| |
Collapse
|
3
|
Su T, Nakamoto R, Chun YY, Chua WZ, Chen JH, Zik JJ, Sham LT. Decoding capsule synthesis in Streptococcus pneumoniae. FEMS Microbiol Rev 2020; 45:6041728. [PMID: 33338218 DOI: 10.1093/femsre/fuaa067] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 12/07/2020] [Indexed: 12/20/2022] Open
Abstract
Streptococcus pneumoniae synthesizes more than one hundred types of capsular polysaccharides (CPS). While the diversity of the enzymes and transporters involved is enormous, it is not limitless. In this review, we summarized the recent progress on elucidating the structure-function relationships of CPS, the mechanisms by which they are synthesized, how their synthesis is regulated, the host immune response against them, and the development of novel pneumococcal vaccines. Based on the genetic and structural information available, we generated provisional models of the CPS repeating units that remain unsolved. In addition, to facilitate cross-species comparisons and assignment of glycosyltransferases, we illustrated the biosynthetic pathways of the known CPS in a standardized format. Studying the intricate steps of pneumococcal CPS assembly promises to provide novel insights for drug and vaccine development as well as improve our understanding of related pathways in other species.
Collapse
Affiliation(s)
- Tong Su
- Infectious Diseases Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117545, Singapore
| | - Rei Nakamoto
- Infectious Diseases Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117545, Singapore
| | - Ye Yu Chun
- Infectious Diseases Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117545, Singapore
| | - Wan Zhen Chua
- Infectious Diseases Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117545, Singapore
| | - Jia Hui Chen
- Infectious Diseases Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117545, Singapore
| | - Justin J Zik
- Infectious Diseases Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117545, Singapore
| | - Lok-To Sham
- Infectious Diseases Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117545, Singapore
| |
Collapse
|
4
|
Whitfield C, Wear SS, Sande C. Assembly of Bacterial Capsular Polysaccharides and Exopolysaccharides. Annu Rev Microbiol 2020; 74:521-543. [PMID: 32680453 DOI: 10.1146/annurev-micro-011420-075607] [Citation(s) in RCA: 132] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Polysaccharides are dominant features of most bacterial surfaces and are displayed in different formats. Many bacteria produce abundant long-chain capsular polysaccharides, which can maintain a strong association and form a capsule structure enveloping the cell and/or take the form of exopolysaccharides that are mostly secreted into the immediate environment. These polymers afford the producing bacteria protection from a wide range of physical, chemical, and biological stresses, support biofilms, and play critical roles in interactions between bacteria and their immediate environments. Their biological and physical properties also drive a variety of industrial and biomedical applications. Despite the immense variation in capsular polysaccharide and exopolysaccharide structures, patterns are evident in strategies used for their assembly and export. This review describes recent advances in understanding those strategies, based on a wealth of biochemical investigations of select prototypes, supported by complementary insight from expanding structural biology initiatives. This provides a framework to identify and distinguish new systems emanating from genomic studies.
Collapse
Affiliation(s)
- Chris Whitfield
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada;
| | - Samantha S Wear
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada;
| | - Caitlin Sande
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada;
| |
Collapse
|
5
|
Whitfield C, Williams DM, Kelly SD. Lipopolysaccharide O-antigens-bacterial glycans made to measure. J Biol Chem 2020; 295:10593-10609. [PMID: 32424042 DOI: 10.1074/jbc.rev120.009402] [Citation(s) in RCA: 92] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 05/17/2020] [Indexed: 01/05/2023] Open
Abstract
Lipopolysaccharides are critical components of bacterial outer membranes. The more conserved lipid A part of the lipopolysaccharide molecule is a major element in the permeability barrier imposed by the outer membrane and offers a pathogen-associated molecular pattern recognized by innate immune systems. In contrast, the long-chain O-antigen polysaccharide (O-PS) shows remarkable structural diversity and fulfills a range of functions, depending on bacterial lifestyles. O-PS production is vital for the success of clinically important Gram-negative pathogens. The biological properties and functions of O-PSs are mostly independent of specific structures, but the size distribution of O-PS chains is particularly important in many contexts. Despite the vast O-PS chemical diversity, most are produced in bacterial cells by two assembly strategies, and the different mechanisms employed in these pathways to regulate chain-length distribution are emerging. Here, we review our current understanding of the mechanisms involved in regulating O-PS chain-length distribution and discuss their impact on microbial cell biology.
Collapse
Affiliation(s)
- Chris Whitfield
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - Danielle M Williams
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - Steven D Kelly
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| |
Collapse
|
6
|
Transcriptome and Comparative Genomics Analyses Reveal New Functional Insights on Key Determinants of Pathogenesis and Interbacterial Competition in Pectobacterium and Dickeya spp. Appl Environ Microbiol 2019; 85:AEM.02050-18. [PMID: 30413477 DOI: 10.1128/aem.02050-18] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 10/29/2018] [Indexed: 02/07/2023] Open
Abstract
Soft-rot Enterobacteriaceae (SRE), typified by Pectobacterium and Dickeya genera, are phytopathogenic bacteria inflicting soft-rot disease in crops worldwide. By combining genomic information from 100 SRE with whole-transcriptome data sets, we identified novel genomic and transcriptional associations among key pathogenicity themes in this group. Comparative genomics revealed solid linkage between the type I secretion system (T1SS) and the carotovoricin bacteriophage (Ctv) conserved in 96.7% of Pectobacterium genomes. Moreover, their coactivation during infection indicates a novel functional association involving T1SS and Ctv. Another bacteriophage-borne genomic region, mostly confined to less than 10% of Pectobacterium strains, was found, presumably comprising a novel lineage-specific prophage in the genus. We also detected the transcriptional coregulation of a previously predicted toxin/immunity pair (WHH and SMI1_KNR4 families), along with the type VI secretion system (T6SS), which includes hcp and/or vgrG genes, suggesting a role in disease development as T6SS-dependent effectors. Further, we showed that another predicted T6SS-dependent endonuclease (AHH family) exhibited toxicity in ectopic expression assays, indicating antibacterial activity. Additionally, we report the striking conservation of the group 4 capsule (GFC) cluster in 100 SRE strains which consistently features adjacently conserved serotype-specific gene arrays comprising a previously unknown organization in GFC clusters. Also, extensive sequence variations found in gfcA orthologs suggest a serotype-specific role in the GfcABCD machinery.IMPORTANCE Despite the considerable loss inflicted on important crops yearly by Pectobacterium and Dickeya diseases, investigations on key virulence and interbacterial competition assets relying on extensive comparative genomics are still surprisingly lacking for these genera. Such approaches become more powerful over time, underpinned by the growing amount of genomic information in public databases. In particular, our findings point to new functional associations among well-known genomic themes enabling alternative means of neutralizing SRE diseases through disruption of pivotal virulence programs. By elucidating novel transcriptional and genomic associations, this study adds valuable information on virulence candidates that could be decisive in molecular applications in the near future. The utilization of 100 genomes of Pectobacterium and Dickeya strains in this study is unprecedented for comparative analyses in these taxa, and it provides novel insights on the biology of economically important plant pathogens.
Collapse
|
7
|
Novel Role of VisP and the Wzz System during O-Antigen Assembly in Salmonella enterica Serovar Typhimurium Pathogenesis. Infect Immun 2018; 86:IAI.00319-18. [PMID: 29866904 DOI: 10.1128/iai.00319-18] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 05/14/2018] [Indexed: 01/18/2023] Open
Abstract
Salmonella enterica serovars are associated with diarrhea and gastroenteritis and are a helpful model for understanding host-pathogen mechanisms. Salmonella enterica serovar Typhimurium regulates the distribution of O antigen (OAg) and presents a trimodal distribution based on Wzy polymerase and the WzzST (long-chain-length OAg [L-OAg]) and WzzfepE (very-long-chain-length OAg [VL-OAg]) copolymerases; however, several mechanisms regulating this process remain unclear. Here, we report that LPS modifications modulate the infectious process and that OAg chain length determination plays an essential role during infection. An increase in VL-OAg is dependent on Wzy polymerase, which is promoted by a growth condition resembling the environment of Salmonella-containing vacuoles (SCVs). The virulence- and stress-related periplasmic protein (VisP) participates in OAg synthesis, as a ΔvisP mutant presents a semirough OAg phenotype. The ΔvisP mutant has greatly decreased motility and J774 macrophage survival in a colitis model of infection. Interestingly, the phenotype is restored after mutation of the wzzST or wzzfepE gene in a ΔvisP background. Loss of both the visP and wzzST genes promotes an imbalance in flagellin secretion. L-OAg may function as a shield against host immune systems in the beginning of an infectious process, and VL-OAg protects bacteria during SCV maturation and facilitates intramacrophage replication. Taken together, these data highlight the roles of OAg length in generating phenotypes during S Typhimurium pathogenesis and show the periplasmic protein VisP as a novel protein in the OAg biosynthesis pathway.
Collapse
|
8
|
Harvey DJ. Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update for 2013-2014. MASS SPECTROMETRY REVIEWS 2018; 37:353-491. [PMID: 29687922 DOI: 10.1002/mas.21530] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 11/29/2016] [Indexed: 06/08/2023]
Abstract
This review is the eighth update of the original article published in 1999 on the application of Matrix-assisted laser desorption/ionization mass spectrometry (MALDI) mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2014. Topics covered in the first part of the review include general aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, fragmentation, and arrays. The second part of the review is devoted to applications to various structural types such as oligo- and poly- saccharides, glycoproteins, glycolipids, glycosides, and biopharmaceuticals. Much of this material is presented in tabular form. The third part of the review covers medical and industrial applications of the technique, studies of enzyme reactions, and applications to chemical synthesis. © 2018 Wiley Periodicals, Inc. Mass Spec Rev 37:353-491, 2018.
Collapse
Affiliation(s)
- David J Harvey
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7FZ, United Kingdom
| |
Collapse
|
9
|
Gao J, Guo Z. Progress in the synthesis and biological evaluation of lipid A and its derivatives. Med Res Rev 2018; 38:556-601. [PMID: 28621828 PMCID: PMC5732894 DOI: 10.1002/med.21447] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 03/09/2017] [Accepted: 04/20/2017] [Indexed: 12/31/2022]
Abstract
Lipid A is one of the core structures of bacterial lipopolysaccharides (LPSs), and it is mainly responsible for the strong immunostimulatory activities of LPS through interactions with the Toll-like receptors and other molecules in the human immune system. To obtain structurally homogeneous and well-defined lipid As and its derivatives in quantities meaningful for various biological studies and applications, their chemical synthesis has become a focal point. This review has provided a survey of significant progresses made in the synthesis of lipid A, and its derivatives that carry diverse saturated and unsaturated lipids, have the phosphate group at its reducing end replaced with a more stable phosphate or carboxyl group, or lack the reducing end phosphate or both phosphate groups, as well as progresses in the synthesis of LPS analogs and other lipid A conjugates. These synthetic molecules have facilitated the elucidation of the structure-activity relationships of lipid A useful for the design and development of lipid A based therapeutics, such as those utilized to treat sepsis, and other medical applications, for example the use of monophosphoryl lipid A as a carrier molecule for the study of fully synthetic self-adjuvanting conjugate vaccines. These topics are also briefly covered in the current review.
Collapse
Affiliation(s)
- Jian Gao
- National Glycoengineering Research Center and Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, 27 Shanda Nan Lu, Jinan 250100, China
| | - Zhongwu Guo
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, Florida 32611, United States
| |
Collapse
|
10
|
Sachdeva S, Palur RV, Sudhakar KU, Rathinavelan T. E. coli Group 1 Capsular Polysaccharide Exportation Nanomachinary as a Plausible Antivirulence Target in the Perspective of Emerging Antimicrobial Resistance. Front Microbiol 2017; 8:70. [PMID: 28217109 PMCID: PMC5290995 DOI: 10.3389/fmicb.2017.00070] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 01/11/2017] [Indexed: 02/02/2023] Open
Abstract
Bacteria evolving resistance against the action of multiple drugs and its ability to disseminate the multidrug resistance trait(s) across various strains of the same bacteria or different bacterial species impose serious threat to public health. Evolution of such multidrug resistance is due to the fact that, most of the antibiotics target bacterial survival mechanisms which exert selective pressure on the bacteria and aids them to escape from the action of antibiotics. Nonetheless, targeting bacterial virulence strategies such as bacterial surface associated polysaccharides biosynthesis and their surface accumulation mechanisms may be an attractive strategy, as they impose less selective pressure on the bacteria. Capsular polysaccharide (CPS) or K-antigen that is located on the bacterial surface armors bacteria from host immune response. Thus, unencapsulating bacteria would be a good strategy for drug design, besides CPS itself being a good vaccine target, by interfering with CPS biosynthesis and surface assembly pathway. Gram-negative Escherichia coli uses Wzy-polymerase dependent (Groups 1 and 4) and ATP dependent (Groups 1 and 3) pathways for CPS production. Considering E. coli as a case in point, this review explains the structure and functional roles of proteins involved in Group 1 Wzy dependent CPS biosynthesis, surface expression and anchorage in relevance to drug and vaccine developments.
Collapse
Affiliation(s)
- Shivangi Sachdeva
- Department of Biotechnology, Indian Institute of Technology Hyderabad Kandi, India
| | - Raghuvamsi V Palur
- Department of Biotechnology, Indian Institute of Technology Hyderabad Kandi, India
| | - Karpagam U Sudhakar
- Department of Biotechnology, Indian Institute of Technology Hyderabad Kandi, India
| | | |
Collapse
|
11
|
Chen C, Liu B, Xu Y, Utkina N, Zhou D, Danilov L, Torgov V, Veselovsky V, Feng L. Biochemical characterization of the novel α-1, 3-galactosyltransferase WclR from Escherichia coli O3. Carbohydr Res 2016; 430:36-43. [PMID: 27196310 DOI: 10.1016/j.carres.2016.04.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 03/24/2016] [Accepted: 04/10/2016] [Indexed: 12/01/2022]
Abstract
Glycosyltransferases (GTs) catalyze the formation of regio- and stereo-specific glycosidic linkages between specific sugar donors and recipients. In this study, the function of the gene wclR from the Escherichia coli O3 O-antigen gene cluster that encodes an α 1, 3-galactosyltransferase (GalT) that acts on the linkage Gal α 1, 3-GlcNAc was biochemically characterized. WclR was expressed in E. coli BL21 (DE3), and the enzymatic product was identified by liquid chromatography-mass spectrometry (LC-MS), collision-induced dissociation electrospray ionization ion trap multiple tandem MS (CID-ESI-IT-MS(n)) and galactosidase digestion, using UDP-Gal as the donor substrate and the synthetic acceptor substrate GlcNAc-PP-De (decyl diphosphate N-acetylglucosamine). The physiochemical properties and the substrate specificity of WclR were investigated. WclR is the first bacterial GalT characterized that acts on the linkage Gal α 1, 3-GlcNAc. This study enhanced our knowledge of the diversified functions of GTs and provided a novel enzyme source for possible pharmaceutical application.
Collapse
Affiliation(s)
- Chao Chen
- TEDA School of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
| | - Bin Liu
- TEDA School of Biological Sciences and Biotechnology, Nankai University, Tianjin, China; The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, China
| | - Yongchang Xu
- TEDA School of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
| | - Natalia Utkina
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Dawei Zhou
- TEDA School of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
| | - Leonid Danilov
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Vladimir Torgov
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Vladimir Veselovsky
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Lu Feng
- TEDA School of Biological Sciences and Biotechnology, Nankai University, Tianjin, China; The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, China.
| |
Collapse
|
12
|
Taylor VL, Hoage JFJ, Thrane SW, Huszczynski SM, Jelsbak L, Lam JS. A Bacteriophage-Acquired O-Antigen Polymerase (Wzyβ) from P. aeruginosa Serotype O16 Performs a Varied Mechanism Compared to Its Cognate Wzyα. Front Microbiol 2016; 7:393. [PMID: 27065964 PMCID: PMC4815439 DOI: 10.3389/fmicb.2016.00393] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 03/14/2016] [Indexed: 12/23/2022] Open
Abstract
Pseudomonas aeruginosa is a Gram-negative bacterium that produces highly varied lipopolysaccharide (LPS) structures. The O antigen (O-Ag) in the LPS is synthesized through the Wzx/Wzy-dependent pathway where lipid-linked O-Ag repeats are polymerized by Wzy. Horizontal-gene transfer has been associated with O-Ag diversity. The O-Ag present on the surface of serotypes O5 and O16, differ in the intra-molecular bonds, α and β, respectively; the latter arose from the action of three genes in a serotype converting unit acquired from bacteriophage D3, including a β-polymerase (Wzyβ). To further our understanding of O-polymerases, the inner membrane (IM) topology of Wzyβ was determined using a dual phoA-lacZα reporter system wherein random 3′ gene truncations were localized to specific loci with respect to the IM by normalized reporter activities as determined through the ratio of alkaline phosphatase activity to β-galactosidase activity. The topology of Wzyβ developed through this approach was shown to contain two predominant periplasmic loops, PL3 (containing an RX10G motif) and PL4 (having an O-Ag ligase superfamily motif), associated with inverting glycosyltransferase reaction. Through site-directed mutagenesis and complementation assays, residues Arg254, Arg270, Arg272, and His300 were found to be essential for Wzyβ function. Additionally, like-charge substitutions, R254K and R270K, could not complement the wzyβ knockout, highlighting the essential guanidium side group of Arg residues. The O-Ag ligase domain is conserved among heterologous Wzy proteins that produce β-linked O-Ag repeat units. Taking advantage of the recently obtained whole-genome sequence of serotype O16 a candidate promoter was identified. Wzyβ under its native promoter was integrated in the PAO1 genome, which resulted in simultaneous production of α- and β-linked O-Ag. These observations established that members of Wzy-like family consistently exhibit a dual-periplasmic loops topology, and identifies motifs that are plausible to be involved in enzymatic activities. Based on these results, the phage-derived Wzyβ utilizes a different reaction mechanism in the P. aeruginosa host to avoid self-inhibition during serotype conversion.
Collapse
Affiliation(s)
- Véronique L Taylor
- Department of Molecular and Cellular Biology, University of Guelph Guelph, ON, Canada
| | - Jesse F J Hoage
- Department of Molecular and Cellular Biology, University of Guelph Guelph, ON, Canada
| | | | - Steven M Huszczynski
- Department of Molecular and Cellular Biology, University of Guelph Guelph, ON, Canada
| | - Lars Jelsbak
- Department of Systems Biology, Technical University of Denmark Kongens Lyngby, Denmark
| | - Joseph S Lam
- Department of Molecular and Cellular Biology, University of Guelph Guelph, ON, Canada
| |
Collapse
|
13
|
Liang J, Li X, Zha T, Chen Y, Hao H, Liu C, Duan R, Xiao Y, Su M, Wang X, Jing H. DTDP-rhamnosyl transferase RfbF, is a newfound receptor-related regulatory protein for phage phiYe-F10 specific for Yersinia enterocolitica serotype O:3. Sci Rep 2016; 6:22905. [PMID: 26965493 PMCID: PMC4786787 DOI: 10.1038/srep22905] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 02/24/2016] [Indexed: 01/21/2023] Open
Abstract
Bacteriophages and their hosts are continuously engaged in evolutionary competition. Here we isolated a lytic phage phiYe-F10 specific for Yersinia enterocolitica serotype O:3. We firstly described the phage receptor was regulated by DTDP-rhamnosyl transferase RfbF, encoded within the rfb cluster that was responsible for the biosynthesis of the O antigens. The deletion of DTDP-rhamnosyl transferase RfbF of wild type O:3 strain caused failure in phiYe-F10 adsorption; however, the mutation strain retained agglutination with O:3 antiserum; and complementation of its mutant converted its sensitivity to phiYe-F10. Therefore, DTDP-rhamnosyl transferase RfbF was responsible for the phage infection but did not affect recognition of Y. enterocolitica O:3 antiserum. Further, the deletions in the putative O-antigen biosynthesis protein precursor and outer membrane protein had no effect on sensitivity to phiYe-F10 infection. However, adsorption of phages onto mutant HNF10-ΔO-antigen took longer time than onto the WT, suggesting that deletion of the putative O-antigen biosynthesis protein precursor reduced the infection efficiency.
Collapse
Affiliation(s)
- Junrong Liang
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, No.155, Changbai Road, Changping, Beijing, 102206, China
| | - Xu Li
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, No.155, Changbai Road, Changping, Beijing, 102206, China
| | - Tao Zha
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, No.155, Changbai Road, Changping, Beijing, 102206, China.,Wuhu Municipal Centre for Disease Control and Prevention, No. 178, Jiuhua central Road, Wuhu, Anhui Province, 241000, China
| | - Yuhuang Chen
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, No.155, Changbai Road, Changping, Beijing, 102206, China
| | - Huijing Hao
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, No.155, Changbai Road, Changping, Beijing, 102206, China
| | - Chang Liu
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, No.155, Changbai Road, Changping, Beijing, 102206, China.,Department of Pathogenic Biology, School of Medical Science, Jiangsu University, Xuefu Road, Zhenjiang, Jiangsu Province, 212013, China
| | - Ran Duan
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, No.155, Changbai Road, Changping, Beijing, 102206, China
| | - Yuchun Xiao
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, No.155, Changbai Road, Changping, Beijing, 102206, China
| | - Mingming Su
- Institute of Biophysics, Chinese Academy of Sciences, No. 15, Datun Road, Chaoyang, Beijing, 100101, China
| | - Xin Wang
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, No.155, Changbai Road, Changping, Beijing, 102206, China
| | - Huaiqi Jing
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, No.155, Changbai Road, Changping, Beijing, 102206, China
| |
Collapse
|
14
|
Mudapaka J, Taylor EA. Cloning and characterization of theEscherichia coliHeptosyltransferase III: Exploring substrate specificity in lipopolysaccharide core biosynthesis. FEBS Lett 2015; 589:1423-9. [DOI: 10.1016/j.febslet.2015.04.051] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 04/22/2015] [Accepted: 04/23/2015] [Indexed: 01/08/2023]
|
15
|
Nath P, Morona R. Mutational analysis of the major periplasmic loops of Shigella flexneri Wzy: identification of the residues affecting O antigen modal chain length control, and Wzz-dependent polymerization activity. MICROBIOLOGY-SGM 2015; 161:774-85. [PMID: 25627441 DOI: 10.1099/mic.0.000042] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 01/19/2015] [Indexed: 01/10/2023]
Abstract
The O antigen (Oag) component of LPS is a major Shigella flexneri virulence determinant. Oag is polymerized by WzySf, and its modal chain length is determined by WzzSf and WzzpHS2. Site-directed mutagenesis was performed on wzySf in pWaldo-wzySf-TEV-GFP to alter Arg residues in WzySf's two large periplasmic loops (PLs) (PL3 and PL5). Analysis of the LPS profiles conferred by mutated WzySf proteins in the wzySf deficient (Δwzy) strain identified residues that affect WzySf activity. The importance of the guanidium group of the Arg residues was investigated by altering the Arg residues to Lys and Glu, which generated WzySf mutants conferring altered LPS Oag modal chain lengths. The dependence of these WzySf mutants on WzzSf was investigated by expressing them in a wzySf and wzzSf deficient (Δwzy Δwzz) strain. Comparison of the LPS profiles identified a role for the Arg residues in the association of WzySf and WzzSf during Oag polymerization. Colicin E2 and bacteriophage Sf6c susceptibility supported this conclusion. Comparison of the expression levels of different mutant WzySf-GFPs with the wild-type WzySf-GFP showed that certain Arg residues affected production levels of WzySf in a WzzSf-dependent manner. To our knowledge, this is the first report of S. flexneri WzySf mutants having an effect on LPS Oag modal chain length, and identified functionally significant Arg residues in WzySf.
Collapse
Affiliation(s)
- Pratiti Nath
- Discipline of Microbiology and Immunology, School of Molecular and Biomedical Science, University of Adelaide, Adelaide 5005, Australia
| | - Renato Morona
- Discipline of Microbiology and Immunology, School of Molecular and Biomedical Science, University of Adelaide, Adelaide 5005, Australia
| |
Collapse
|
16
|
Taylor VL, Huszczynski SM, Lam JS. Membrane Translocation and Assembly of Sugar Polymer Precursors. Curr Top Microbiol Immunol 2015; 404:95-128. [PMID: 26853690 DOI: 10.1007/82_2015_5014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Bacterial polysaccharides play an essential role in cell viability, virulence, and evasion of host defenses. Although the polysaccharides themselves are highly diverse, the pathways by which bacteria synthesize these essential polymers are conserved in both Gram-negative and Gram-positive organisms. By utilizing a lipid linker, a series of glycosyltransferases and integral membrane proteins act in concert to synthesize capsular polysaccharide, teichoic acid, and teichuronic acid. The pathways used to produce these molecules are the Wzx/Wzy-dependent, the ABC-transporter-dependent, and the synthase-dependent pathways. This chapter will cover the initiation, synthesis of the various polysaccharides on the cytoplasmic face of the membrane using nucleotide sugar precursors, and export of the nascent chain from the cytoplasm to the extracellular milieu. As microbial glycobiology is an emerging field in Gram-positive bacteria research, parallels will be drawn to the more widely studied polysaccharide biosynthesis systems in Gram-negative species in order to provide greater understanding of these biologically significant molecules.
Collapse
Affiliation(s)
- Véronique L Taylor
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, N1G 2W1, Canada
| | - Steven M Huszczynski
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, N1G 2W1, Canada
| | - Joseph S Lam
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, N1G 2W1, Canada.
| |
Collapse
|
17
|
Islam ST, Lam JS. Synthesis of bacterial polysaccharides via the Wzx/Wzy-dependent pathway. Can J Microbiol 2014; 60:697-716. [DOI: 10.1139/cjm-2014-0595] [Citation(s) in RCA: 162] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The surfaces of bacteria mediate a multitude of functions in the environment and in an infected host, including adhesion to both biotic and abiotic substrata, motility, immune system interaction and (or) activation, biofilm formation, and cell–cell communication, with many of these features directly influenced by cell-surface glycans. In both Gram-negative and Gram-positive bacteria, the majority of cell-surface polysaccharides are produced via the Wzx/Wzy-dependent assembly pathway; these glycans include heteropolymeric O-antigen, enterobacterial common antigen, exopolysaccharide, spore coat, and capsule in diverse bacteria. The key components of this assembly pathway are the integral inner membrane Wzx flippase, Wzy polymerase, and Wzz chain-length regulator proteins, which until recently have resisted detailed structural and functional characterization. In this review, we have provided a comprehensive synthesis of the latest structural and mechanistic data for each protein, as well as an examination of substrate specificity for each assembly step and complex formation between the constituent proteins. To complement the unprecedented explosion of genomic-sequencing data for bacteria, we have also highlighted both classical and state-of-the-art methods by which encoded Wzx, Wzy, and Wzz proteins can be reliably identified and annotated, using the model Gram-negative bacterium Pseudomonas aeruginosa as an example data set. Lastly, we outline future avenues of research, with the aim of stimulating researchers to take the next steps in investigating the function of, and interplay between, the constituents of this widespread assembly scheme.
Collapse
Affiliation(s)
- Salim T. Islam
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Joseph S. Lam
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| |
Collapse
|