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Liu B, Furevi A, Perepelov AV, Guo X, Cao H, Wang Q, Reeves PR, Knirel YA, Wang L, Widmalm G. Structure and genetics of Escherichia coli O antigens. FEMS Microbiol Rev 2020; 44:655-683. [PMID: 31778182 PMCID: PMC7685785 DOI: 10.1093/femsre/fuz028] [Citation(s) in RCA: 121] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 11/22/2019] [Indexed: 02/07/2023] Open
Abstract
Escherichia coli includes clonal groups of both commensal and pathogenic strains, with some of the latter causing serious infectious diseases. O antigen variation is current standard in defining strains for taxonomy and epidemiology, providing the basis for many serotyping schemes for Gram-negative bacteria. This review covers the diversity in E. coli O antigen structures and gene clusters, and the genetic basis for the structural diversity. Of the 187 formally defined O antigens, six (O31, O47, O67, O72, O94 and O122) have since been removed and three (O34, O89 and O144) strains do not produce any O antigen. Therefore, structures are presented for 176 of the 181 E. coli O antigens, some of which include subgroups. Most (93%) of these O antigens are synthesized via the Wzx/Wzy pathway, 11 via the ABC transporter pathway, with O20, O57 and O60 still uncharacterized due to failure to find their O antigen gene clusters. Biosynthetic pathways are given for 38 of the 49 sugars found in E. coli O antigens, and several pairs or groups of the E. coli antigens that have related structures show close relationships of the O antigen gene clusters within clades, thereby highlighting the genetic basis of the evolution of diversity.
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Affiliation(s)
- Bin Liu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjing 300457, China
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, 23 Hongda Street, TEDA, Tianjin 300457, China
- Tianjin Key Laboratory of Microbial Functional Genomics, 23 Hongda Street, TEDA, Tianjin 300457, China
| | - Axel Furevi
- Department of Organic Chemistry, Arrhenius Laboratory, Svante Arrhenius väg 16C, Stockholm University, S-106 91 Stockholm, Sweden
| | - Andrei V Perepelov
- N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Prospect, 47, Moscow, Russia
| | - Xi Guo
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjing 300457, China
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, 23 Hongda Street, TEDA, Tianjin 300457, China
- Tianjin Key Laboratory of Microbial Functional Genomics, 23 Hongda Street, TEDA, Tianjin 300457, China
| | - Hengchun Cao
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjing 300457, China
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, 23 Hongda Street, TEDA, Tianjin 300457, China
- Tianjin Key Laboratory of Microbial Functional Genomics, 23 Hongda Street, TEDA, Tianjin 300457, China
| | - Quan Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjing 300457, China
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, 23 Hongda Street, TEDA, Tianjin 300457, China
- Tianjin Key Laboratory of Microbial Functional Genomics, 23 Hongda Street, TEDA, Tianjin 300457, China
| | - Peter R Reeves
- School of Molecular and Microbial Bioscience, University of Sydney, 2 Butilin Ave, Darlington NSW 2008, Sydney, Australia
| | - Yuriy A Knirel
- N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Prospect, 47, Moscow, Russia
| | - Lei Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjing 300457, China
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, 23 Hongda Street, TEDA, Tianjin 300457, China
- Tianjin Key Laboratory of Microbial Functional Genomics, 23 Hongda Street, TEDA, Tianjin 300457, China
| | - Göran Widmalm
- Department of Organic Chemistry, Arrhenius Laboratory, Svante Arrhenius väg 16C, Stockholm University, S-106 91 Stockholm, Sweden
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Xu Y, Guo Y, Gao Y, Niu X, Wang L, Li X, Chen H, Yu Z, Yang Y. Seperation, characterization and inhibition on α-glucosidase, α-amylase and glycation of a polysaccharide from blackcurrant fruits. Lebensm Wiss Technol 2018. [DOI: 10.1016/j.lwt.2018.03.023] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Xu Y, Gao Y, Liu F, Niu X, Wang L, Li X, Chen H, Yang Y. Sulfated modification of the polysaccharides from blackcurrant and their antioxidant and α-amylase inhibitory activities. Int J Biol Macromol 2018; 109:1344-1354. [DOI: 10.1016/j.ijbiomac.2017.11.164] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 11/10/2017] [Accepted: 11/25/2017] [Indexed: 12/23/2022]
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Pierdominici-Sottile G, Cossio Pérez R, Galindo JF, Palma J. QM/MM molecular dynamics study of the galactopyranose → galactofuranose reaction catalysed by Trypanosoma cruzi UDP-galactopyranose mutase. PLoS One 2014; 9:e109559. [PMID: 25299056 PMCID: PMC4192007 DOI: 10.1371/journal.pone.0109559] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Accepted: 08/25/2014] [Indexed: 12/18/2022] Open
Abstract
The enzyme UDP-Galactopyranose Mutase (UGM) catalyses the conversion of galactopyranose into galactofuranose. It is known to be critical for the survival and proliferation of several pathogenic agents, both prokaryotic and eukaryotic. Among them is Trypanosoma cruzi, the parasite responsible for Chagas' disease. Since the enzyme is not present in mammals, it appears as a promising target for the design of drugs to treat this illness. A precise knowledge of the mechanism of the catalysed reaction would be crucial to assist in such design. In this article we present a detailed study of all the putative steps of the mechanism. The study is based on QM/MM free energy calculations along properly selected reaction coordinates, and on the analysis of the main structural changes and interactions taking place at every step. The results are discussed in connection with the experimental evidence and previous theoretical studies.
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Affiliation(s)
| | - Rodrigo Cossio Pérez
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Bernal, Argentina
| | - Johan F. Galindo
- Quantum and Computational Chemistry Group, Departamento de Química, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Juliana Palma
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Bernal, Argentina
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Jana M, Misra AK. Straightforward synthesis of a tetrasaccharide repeating unit corresponding to the O-antigen of Escherichia coli O16. Beilstein J Org Chem 2013; 9:1757-62. [PMID: 24062839 PMCID: PMC3778367 DOI: 10.3762/bjoc.9.203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Accepted: 08/09/2013] [Indexed: 11/23/2022] Open
Abstract
A straightforward synthesis of the tetrasaccharide repeating unit of the O-antigen of Escherichia coli O16 has been achieved following a sequential glycosylation strategy. A minimum number of steps was used for the synthesis of the target compound involving a one-pot glycosylation and a protecting group manipulation. All intermediate reactions afford their products in high yield, and the glycosylation steps are stereoselective.
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Affiliation(s)
- Manas Jana
- Bose Institute, Division of Molecular Medicine, P-1/12, C.I.T. Scheme VII-M, Kolkata-700054, India
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The lipopolysaccharide of the mastitis isolate Escherichia coli strain 1303 comprises a novel O-antigen and the rare K-12 core type. Microbiology (Reading) 2011; 157:1750-1760. [DOI: 10.1099/mic.0.046912-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Mastitis represents one of the most significant health problems of dairy herds. The two major causative agents of this disease are Escherichia coli and Staphylococcus aureus. Of the first, its lipopolysaccharide (LPS) is thought to play a prominent role during infection. Here, we report the O-antigen (OPS, O-specific polysaccharide) structure of the LPS from bovine mastitis isolate E. coli 1303. The structure was determined utilizing chemical analyses, mass spectrometry, and 1D and 2D NMR spectroscopy methods. The O-repeating unit was characterized as -[→4)-β-d-Quip3NAc-(1→3)-α-l-Fucp2OAc-(1→4)-β-d-Galp-(1→3)-α-d-GalpNAc-(1→]- in which the O-acetyl substitution was non-stoichiometric. The nucleotide sequence of the O-antigen gene cluster of E. coli 1303 was also determined. This cluster, located between the gnd and galF genes, contains 13 putative open reading frames, most of which represent unknown nucleotide sequences that have not been described before. The O-antigen of E. coli 1303 was shown to substitute O-7 of the terminal ld-heptose of the K-12 core oligosaccharide. Interestingly, the non-OPS-substituted core oligosaccharide represented a truncated version of the K-12 outer core – namely terminal ld-heptose and glucose were missing; however, it possessed a third Kdo residue in the inner core. On the basis of structural and genetic data we show that the mastitis isolate E. coli 1303 represents a new serotype and possesses the K-12 core type, which is rather uncommon among human and bovine isolates.
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Fujita M, Tsuchida A, Hirata A, Kobayashi N, Goto K, Osumi K, Hirose Y, Nakayama J, Yamanoi T, Ashida H, Mizuno M. Glycoside hydrolase family 89 alpha-N-acetylglucosaminidase from Clostridium perfringens specifically acts on GlcNAc alpha1,4Gal beta1R at the non-reducing terminus of O-glycans in gastric mucin. J Biol Chem 2010; 286:6479-89. [PMID: 21177247 DOI: 10.1074/jbc.m110.206722] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
In mammals, α-linked GlcNAc is primarily found in heparan sulfate/heparin and gastric gland mucous cell type mucin. α-N-acetylglucosaminidases (αGNases) belonging to glycoside hydrolase family 89 are widely distributed from bacteria to higher eukaryotes. Human lysosomal αGNase is well known to degrade heparin and heparan sulfate. Here, we reveal the substrate specificity of αGNase (AgnC) from Clostridium perfringens strain 13, a bacterial homolog of human αGNase, by chemically synthesizing a series of disaccharide substrates containing α-linked GlcNAc. AgnC was found to release GlcNAc from GlcNAcα1,4Galβ1pMP and GlcNAcα1pNP substrates (where pMP and pNP represent p-methoxyphenyl and p-nitrophenyl, respectively). AgnC also released GlcNAc from porcine gastric mucin and cell surface mucin. Because AgnC showed no activity against any of the GlcNAcα1,2Galβ1pMP, GlcNAcα1,3Galβ1pMP, GlcNAcα1,6Galβ1pMP, and GlcNAcα1,4GlcAβ1pMP substrates, this enzyme may represent a specific glycosidase required for degrading α-GlcNAc-capped O-glycans of the class III mucin secreted from the stomach and duodenum. Deletion of the C-terminal region containing several carbohydrate-binding module 32 (CBM32) domains significantly reduced the activity for porcine gastric mucin; however, activity against GlcNAcα1,4Galβ1pMP was markedly enhanced. Dot blot and ELISA analyses revealed that the deletion construct containing the C-terminal CBM-C2 to CBM-C6 domains binds strongly to porcine gastric mucin. Consequently, tandem CBM32 domains located near the C terminus of AgnC should function by increasing the affinity for branched or clustered α-GlcNAc-containing glycans. The agnC gene-disrupted strain showed significantly reduced growth on the class III mucin-containing medium compared with the wild type strain, suggesting that AgnC might have an important role in dominant growth in intestines.
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Affiliation(s)
- Masaya Fujita
- Noguchi Institute, 1-8-1 Kaga, Itabashi, Tokyo 173-0003, Japan.
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Osorio-Román IO, Aroca RF, Astudillo J, Matsuhiro B, Vásquez C, Pérez JM. Characterization of bacteria using its O-antigen with surface-enhanced Raman scattering. Analyst 2010; 135:1997-2001. [DOI: 10.1039/c0an00061b] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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9
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Ligand binding and substrate discrimination by UDP-galactopyranose mutase. J Mol Biol 2009; 391:327-40. [PMID: 19500588 DOI: 10.1016/j.jmb.2009.05.081] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2009] [Revised: 05/20/2009] [Accepted: 05/27/2009] [Indexed: 11/23/2022]
Abstract
Galactofuranose (Galf) residues are present in cell wall glycoconjugates of numerous pathogenic microbes. Uridine 5'-diphosphate (UDP) Galf, the biosynthetic precursor of Galf-containing glycoconjugates, is produced from UDP-galactopyranose (UDP-Galp) by the flavoenzyme UDP-galactopyranose mutase (UGM). The gene encoding UGM (glf) is essential for the viability of pathogens, including Mycobacterium tuberculosis, and this finding underscores the need to understand how UGM functions. Considerable effort has been devoted to elucidating the catalytic mechanism of UGM, but progress has been hindered by a lack of structural data for an enzyme-substrate complex. Such data could reveal not only substrate binding interactions but how UGM can act preferentially on two very different substrates, UDP-Galp and UDP-Galf, yet avoid other structurally related UDP sugars present in the cell. Herein, we describe the first structure of a UGM-ligand complex, which provides insight into the catalytic mechanism and molecular basis for substrate selectivity. The structure of UGM from Klebsiella pneumoniae bound to the substrate analog UDP-glucose (UDP-Glc) was solved by X-ray crystallographic methods and refined to 2.5 A resolution. The ligand is proximal to the cofactor, a finding that is consistent with a proposed mechanism in which the reduced flavin engages in covalent catalysis. Despite this proximity, the glucose ring of the substrate analog is positioned such that it disfavors covalent catalysis. This orientation is consistent with data indicating that UDP-Glc is not a substrate for UGM. The relative binding orientations of UDP-Galp and UDP-Glc were compared using saturation transfer difference NMR. The results indicate that the uridine moiety occupies a similar location in both ligand complexes, and this relevant binding mode is defined by our structural data. In contrast, the orientations of the glucose and galactose sugar moieties differ. To understand the consequences of these differences, we derived a model for the productive UGM-substrate complex that highlights interactions that can contribute to catalysis and substrate discrimination.
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Peltier P, Euzen R, Daniellou R, Nugier-Chauvin C, Ferrières V. Recent knowledge and innovations related to hexofuranosides: structure, synthesis and applications. Carbohydr Res 2008; 343:1897-923. [DOI: 10.1016/j.carres.2008.02.010] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2007] [Revised: 02/08/2008] [Accepted: 02/12/2008] [Indexed: 10/22/2022]
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Carlson EE, May JF, Kiessling LL. Chemical probes of UDP-galactopyranose mutase. ACTA ACUST UNITED AC 2006; 13:825-37. [PMID: 16931332 DOI: 10.1016/j.chembiol.2006.06.007] [Citation(s) in RCA: 112] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2006] [Revised: 06/05/2006] [Accepted: 06/06/2006] [Indexed: 12/26/2022]
Abstract
Many pathogenic prokaryotes and eukaryotes possess the machinery required to assemble galactofuranose (Galf)-containing glycoconjugates; these glycoconjugates can be critical for virulence or viability. Accordingly, compounds that block Galf incorporation may serve as therapeutic leads or as probes of the function of Galf-containing glycoconjugates. The enzyme UDP-galactopyranose mutase (UGM) is the only known generator of UDP-galactofuranose, the precursor to Galf residues. We previously employed a high-throughput fluorescence polarization assay to investigate the Klebsiella pneumoniae UGM. We demonstrate the generality of this assay by extending it to UGM from Mycobacterium tuberculosis. To identify factors influencing binding, we synthesized a directed library containing a 5-arylidene-2-thioxo-4-thiazolidinone core, a structure possessing features common to ligands for both homologs. Our studies offer a blueprint for identifying inhibitors of the growing family of UGM homologs and provide insight into UGM inhibition.
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Affiliation(s)
- Erin E Carlson
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
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12
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Mills JA, Motichka K, Jucker M, Wu HP, Uhlik BC, Stern RJ, Scherman MS, Vissa VD, Pan F, Kundu M, Ma YF, McNeil M. Inactivation of the mycobacterial rhamnosyltransferase, which is needed for the formation of the arabinogalactan-peptidoglycan linker, leads to irreversible loss of viability. J Biol Chem 2004; 279:43540-6. [PMID: 15294902 DOI: 10.1074/jbc.m407782200] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Temperature-sensitive mutant 2-20/32 of Mycobacterium smegmatis mc(2)155 was isolated and genetically complemented with a Mycobacterium tuberculosis H37Rv DNA fragment that contained a single open reading frame. This open reading frame is designated Rv3265c in the M. tuberculosis H37Rv genome. Rv3265c shows homology to the Escherichia coli gene wbbL, which encodes a dTDP-Rha:alpha-D-GlcNAc-pyrophosphate polyprenol, alpha-3-L-rhamnosyltransferase. In E. coli this enzyme is involved in O-antigen synthesis, but in mycobacteria it is required for the rhamnosyl-containing linker unit responsible for the attachment of the cell wall polymer mycolyl-arabinogalactan to the peptidoglycan. The M. tuberculosis wbbL homologue, encoded by Rv3265c, was shown to be capable of restoring an E. coli K12 strain containing an insertionally inactivated wbbL to O-antigen positive. Likewise, the E. coli wbbL gene allowed 2-20/32 to grow at higher non-permissive temperatures. The rhamnosyltransferase activity of M. tuberculosis WbbL was demonstrated in 2-20/32 as was the loss of this transferase activity in 2-20/32 at elevated temperatures. The wbbL of the temperature-sensitive mutant contained a single-base change that converted what was a proline in mc(2)155 to a serine residue. Exposure of 2-20/32 to higher non-permissive temperatures resulted in bacteria that could not be recovered at the lower permissive temperatures.
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Affiliation(s)
- Jonathan A Mills
- Chugai Biopharmaceuticals, Inc., San Diego, California 92121, USA
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Batley M, Redmond JW, Packer NH, Liu D, Reeves P. The relationship between the structures of the O polysaccharides from Escherichia coli O17 and O16. Carbohydr Res 1997; 303:313-8. [PMID: 9373936 DOI: 10.1016/s0008-6215(97)00177-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The chemical structure of the O16 antigen from the lipopolysaccharide of Escherichia coli strain P4 has been determined. Comparison with the structures of other O16 antigens and that of the O17 antigen explains the previously reported cross-reaction of O antigen from the O16 strain K-12 with anti-O17 antibody [D. Liu and P.R. Reeves, Microbiology, 140 (1994) 49-57].
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Affiliation(s)
- M Batley
- School of Chemistry, Macquarie University, New South Wales, Australia
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14
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Elvebak LE, Wittmeyer P, Gray GR. Authentic standards for the reductive-cleavage method. The positional isomers of partially methylated and acetylated or benzoylated 1,5-anhydro-l-rhamnitol. Carbohydr Res 1997. [DOI: 10.1016/s0008-6215(97)00008-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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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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Mulloy B. High-field NMR as a technique for the determination of polysaccharide structures. Mol Biotechnol 1996; 6:241-65. [PMID: 9067973 DOI: 10.1007/bf02761706] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
NMR spectroscopy has played a developing role in the study of polysaccharide structures for over 30 years. Many new bacterial polysaccharide repeat unit structures have recently been published as a result of the application of modern NMR techniques. NMR can also be used to elucidate the structures of both regular and heterogeneous polysaccharides from fungal and plant sources, as well as complex glycosaminoglycans of animal origin. In addition to covalent structure, conformation and dynamics of polysaccharides are susceptible to NMR analysis, both in solution and in the solid state. Improvements in NMR technology with potential applications to polysaccharide studies hold promise for the future.
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Affiliation(s)
- B Mulloy
- Laboratory for Molecular Structure, National Institute for Biological Standards and Control, Hertfordshire, UK
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