o antigens


Summary: The lipopolysaccharide-protein somatic antigens, usually from gram-negative bacteria, important in the serological classification of enteric bacilli. The O-specific chains determine the specificity of the O antigens of a given serotype. O antigens are the immunodominant part of the lipopolysaccharide molecule in the intact bacterial cell. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)

Top Publications

  1. Perepelov A, Zabłotni A, Shashkov A, Knirel Y, Sidorczyk Z. Structure of the O-polysaccharide of Proteus mirabilis CCUG 10705 (OF) containing an amide of D-galacturonic acid with L-alanine. Carbohydr Res. 2006;341:1969-74 pubmed
    ..mirabilis OF and P. mirabilis O5 was observed and accounted for by a similarity of their O-repeating units. The following structure of the polysaccharide of P. mirabilis OF was established: [chemical structure: see text] ..
  2. Bugarel M, Beutin L, Martin A, Gill A, Fach P. Micro-array for the identification of Shiga toxin-producing Escherichia coli (STEC) seropathotypes associated with Hemorrhagic Colitis and Hemolytic Uremic Syndrome in humans. Int J Food Microbiol. 2010;142:318-29 pubmed publisher
    ..coli (EHEC) serotypes. The genes selected for determination of the O antigens (rfbE(O157), wzx(O26), wzx(O103), wbd1(O111), ihp1(O145), wzx(O121), wzy(O113), wzy(O91), wzx(O104), wzy(O118), ..
  3. Reeves P, Cunneen M, Liu B, Wang L. Genetics and evolution of the Salmonella galactose-initiated set of o antigens. PLoS ONE. 2013;8:e69306 pubmed publisher
    This paper covers eight Salmonella serogroups, that are defined by O antigens with related structures and gene clusters. They include the serovars that are now most frequently isolated...
  4. Kubler Kielb J, Whitfield C, Katzenellenbogen E, Vinogradov E. Identification of the methyl phosphate substituent at the non-reducing terminal mannose residue of the O-specific polysaccharides of Klebsiella pneumoniae O3, Hafnia alvei PCM 1223 and Escherichia coli O9/O9a LPS. Carbohydr Res. 2012;347:186-8 pubmed publisher
    ..Here we show that all above polysaccharides contain the same modification at the non-reducing end; presence of a methyl phosphate group at O-3 of ?-mannopyranose, that serves as the signal for termination of the chain elongation...
  5. Yan M, Tam F, Kan B, Lim P. Combined rapid (TUBEX) test for typhoid-paratyphoid A fever based on strong anti-O12 response: design and critical assessment of sensitivity. PLoS ONE. 2011;6:e24743 pubmed publisher
    ..Paired sera analysis was insightful, revealing 64% of typhoid patients who had no change in antibody titer over 4-16 days, and 14% with no IgM-IgG class-switching...
  6. Pescaretti M, Lopez F, Morero R, Delgado M. The PmrA/PmrB regulatory system controls the expression of the wzzfepE gene involved in the O-antigen synthesis of Salmonella enterica serovar Typhimurium. Microbiology. 2011;157:2515-21 pubmed publisher
    ..The results obtained here highlight functional differences between Wzz(fepE) and Wzz(st), although the genes for both proteins are regulated in a PmrA-dependent way. ..
  7. Islam S, Gold A, Taylor V, Anderson E, Ford R, Lam J. Dual conserved periplasmic loops possess essential charge characteristics that support a catch-and-release mechanism of O-antigen polymerization by Wzy in Pseudomonas aeruginosa PAO1. J Biol Chem. 2011;286:20600-5 pubmed publisher
    ..These observations support the proposed role of each PL in a catch-and-release mechanism for Wzy-mediated O-antigen polymerization. ..
  8. Coimbra R, Artiguenave F, Jacques L, Oliveira G. MST (molecular serotyping tool): a program for computer-assisted molecular identification of Escherichia coli and Shigella O antigens. J Clin Microbiol. 2010;48:1921-3 pubmed publisher
    Escherichia coli and Shigella O antigens can be inferred using the rfb-restriction fragment length polymorphism (RFLP) molecular test...
  9. Lee Y, Jeong S, In Y, Kim K, So J, Chang W. Lack of O-polysaccharide enhances biofilm formation by Bradyrhizobium japonicum. Lett Appl Microbiol. 2010;50:452-6 pubmed publisher
    ..To reveal the effects of the O-polysaccharide antigen of Bradyrhizobium japonicum LPS on biofilm formation and motility...

More Information


  1. Marolda C, Li B, Lung M, Yang M, Hanuszkiewicz A, Rosales A, et al. Membrane topology and identification of critical amino acid residues in the Wzx O-antigen translocase from Escherichia coli O157:H4. J Bacteriol. 2010;192:6160-71 pubmed publisher
    ..We propose that the functional requirement of charged residues at both sides of the membrane and in two TM helices could be important to allow the passage of the Und-PP-linked saccharide substrate across the membrane. ..
  2. King J, Berry S, Clarke B, Morris R, Whitfield C. Lipopolysaccharide O antigen size distribution is determined by a chain extension complex of variable stoichiometry in Escherichia coli O9a. Proc Natl Acad Sci U S A. 2014;111:6407-12 pubmed publisher
    ..Our work highlights limitations of previous models and provides new insight into the mechanisms of length control in polysaccharide biosynthesis. ..
  3. Kalynych S, Valvano M, Cygler M. Polysaccharide co-polymerases: the enigmatic conductors of the O-antigen assembly orchestra. Protein Eng Des Sel. 2012;25:797-802 pubmed publisher
    ..Here we review the current knowledge of structure and function of these polysaccharide length regulators. ..
  4. Seed K, Faruque S, Mekalanos J, Calderwood S, Qadri F, Camilli A. Phase variable O antigen biosynthetic genes control expression of the major protective antigen and bacteriophage receptor in Vibrio cholerae O1. PLoS Pathog. 2012;8:e1002917 pubmed publisher
  5. Tang G, Ruiz T, Mintz K. O-polysaccharide glycosylation is required for stability and function of the collagen adhesin EmaA of Aggregatibacter actinomycetemcomitans. Infect Immun. 2012;80:2868-77 pubmed publisher
    ..The glycan modification of EmaA appears to be required for collagen binding activity and protection of the protein against degradation by proteolytic enzymes. ..
  6. Vitiazeva V, Twelkmeyer B, Young R, Hood D, Schweda E. Structural studies of the lipopolysaccharide from Haemophilus parainfluenzae strain 20. Carbohydr Res. 2011;346:2228-36 pubmed publisher
    ..LPS from a wbaP mutant of H. parainfluenzae strain 20 did not contain an O-antigen, consistent with the wbaP gene product being required for expression of O-antigen in fully extended LPS...
  7. Kim T, Sebastian S, Pinkham J, ROSS R, Blalock L, Kasper D. Characterization of the O-antigen polymerase (Wzy) of Francisella tularensis. J Biol Chem. 2010;285:27839-49 pubmed publisher
    ..Topology models indicate that these amino acids most likely lie in close proximity on the bacterial surface. ..
  8. Simon R, Tennant S, Wang J, Schmidlein P, Lees A, Ernst R, et al. Salmonella enterica serovar enteritidis core O polysaccharide conjugated to H:g,m flagellin as a candidate vaccine for protection against invasive infection with S. enteritidis. Infect Immun. 2011;79:4240-9 pubmed publisher
    ..Enteritidis cells into mouse macrophages. Mice immunized with flagellin alone, COPS-CRM???, or COPS-flagellin conjugates were significantly protected from lethal challenge with wild-type S. Enteritidis (80 to 100% vaccine efficacy)...
  9. Ruan X, Loyola D, Marolda C, Perez Donoso J, Valvano M. The WaaL O-antigen lipopolysaccharide ligase has features in common with metal ion-independent inverting glycosyltransferases. Glycobiology. 2012;22:288-99 pubmed publisher
    ..Together, our biochemical and in silico data argue that WaaL proteins use a common reaction mechanism and share features of metal ion-independent inverting glycosyltransferases...
  10. Zygmunt M, Jacques I, Bernardet N, Cloeckaert A. Lipopolysaccharide heterogeneity in the atypical group of novel emerging Brucella species. Clin Vaccine Immunol. 2012;19:1370-3 pubmed publisher
    ..These results have several implications for serological typing and serological diagnosis and underline the need for novel tools for detection and correct identification of such novel emerging Brucella spp...
  11. King J, Vinogradov E, Tran V, Lam J. Biosynthesis of uronamide sugars in Pseudomonas aeruginosa O6 and Escherichia coli O121 O antigens. Environ Microbiol. 2010;12:1531-44 pubmed publisher
    ..The E. coli O121 wbqG mutant O antigen contains 2-acetamido-2-deoxy-d-galacturonate (d-GalNAcA), instead of d-GalNAcAN, demonstrating that wbqG is specifically required for biosynthesis of the carboxamide in this sugar. ..
  12. Broadbent S, Davies M, van der Woude M. Phase variation controls expression of Salmonella lipopolysaccharide modification genes by a DNA methylation-dependent mechanism. Mol Microbiol. 2010;77:337-53 pubmed publisher
    ..Most Salmonella gtr operons share the key regulatory elements that are identified here as essential for this epigenetic phase variation...
  13. Haurat M, Aduse Opoku J, Rangarajan M, Dorobantu L, Gray M, Curtis M, et al. Selective sorting of cargo proteins into bacterial membrane vesicles. J Biol Chem. 2011;286:1269-76 pubmed publisher
    ..The existence of a process to package specific virulence factors into OMV may significantly alter our current understanding of host-pathogen interactions. ..
  14. Wildschutte H, Preheim S, Hernandez Y, Polz M. O-antigen diversity and lateral transfer of the wbe region among Vibrio splendidus isolates. Environ Microbiol. 2010;12:2977-87 pubmed publisher
    ..Our results demonstrate O-antigen hyper-variability among these environmental strains and suggest that frequent lateral gene transfer generates wbe extensive diversity among V. splendidus and its close relatives. ..
  15. Fratamico P, Bagi L, Cray W, Narang N, Yan X, Medina M, et al. Detection by multiplex real-time polymerase chain reaction assays and isolation of Shiga toxin-producing Escherichia coli serogroups O26, O45, O103, O111, O121, and O145 in ground beef. Foodborne Pathog Dis. 2011;8:601-7 pubmed publisher
    ..This work provides a method for detection and isolation in ground beef and potentially other foods of non-O157 STEC of major public health concern. ..
  16. Rump L, Beutin L, Fischer M, Feng P. Characterization of a gne::IS629 O rough:H7 Escherichia coli strain from a hemorrhagic colitis patient. Appl Environ Microbiol. 2010;76:5290-1 pubmed publisher
    ..Recently, an O rough:H7 strain caused by gne::IS629 was isolated from a hemorrhagic colitis patient, suggesting that these strains are pathogenic and may not be as rare as anticipated. ..
  17. Islam S, Fieldhouse R, Anderson E, Taylor V, Keates R, Ford R, et al. A cationic lumen in the Wzx flippase mediates anionic O-antigen subunit translocation in Pseudomonas aeruginosa PAO1. Mol Microbiol. 2012;84:1165-76 pubmed publisher
    ..This is the first report to describe a charged flippase lumen for mediating anionic O-unit translocation across the hydrophobic IM. ..
  18. Kalynych S, Ruan X, Valvano M, Cygler M. Structure-guided investigation of lipopolysaccharide O-antigen chain length regulators reveals regions critical for modal length control. J Bacteriol. 2011;193:3710-21 pubmed publisher
    ..Together, our data suggest that chain length determination depends on regions that likely contribute to stabilize a supramolecular complex...
  19. Tzschoppe M, Martin A, Beutin L. A rapid procedure for the detection and isolation of enterohaemorrhagic Escherichia coli (EHEC) serogroup O26, O103, O111, O118, O121, O145 and O157 strains and the aggregative EHEC O104:H4 strain from ready-to-eat vegetables. Int J Food Microbiol. 2012;152:19-30 pubmed publisher
    ..Aggregative EHEC O104:H4 could be detected and isolated from a sample of sprouted seeds which was suspected as vector of transmission of EHEC O104 to humans. ..
  20. Quiñones B, Swimley M, Narm K, Patel R, Cooley M, Mandrell R. O-antigen and virulence profiling of shiga toxin-producing Escherichia coli by a rapid and cost-effective DNA microarray colorimetric method. Front Cell Infect Microbiol. 2012;2:61 pubmed publisher
  21. Park J, Zhang Y, Buboltz A, Zhang X, Schuster S, Ahuja U, et al. Comparative genomics of the classical Bordetella subspecies: the evolution and exchange of virulence-associated diversity amongst closely related pathogens. BMC Genomics. 2012;13:545 pubmed publisher
    ..The compelling picture from previous comparisons of the three sequenced genomes was of genome degradation, with substantial loss of genome content (up to 24%) associated with adaptation to humans...
  22. Tuanyok A, Stone J, Mayo M, Kaestli M, Gruendike J, Georgia S, et al. The genetic and molecular basis of O-antigenic diversity in Burkholderia pseudomallei lipopolysaccharide. PLoS Negl Trop Dis. 2012;6:e1453 pubmed publisher
    ..We postulate that the diversity of LPS may correlate with differential immunopathogenicity and virulence among B. pseudomallei strains. ..
  23. Mayer L, Vendruscolo C, Silva W, Vorhölter F, Becker A, Pühler A. Insights into the genome of the xanthan-producing phytopathogen Xanthomonas arboricola pv. pruni 109 by comparative genomic hybridization. J Biotechnol. 2011;155:40-9 pubmed publisher
    ..arboricola pv. pruni 109 differs from that of Xcc B100 and Xcv 85-10. ..
  24. Wang J, Knirel Y, Lan R, Senchenkova S, Luo X, Perepelov A, et al. Identification of an O-acyltransferase gene (oacB) that mediates 3- and 4-O-acetylation of rhamnose III in Shigella flexneri O antigens. J Bacteriol. 2014;196:1525-31 pubmed publisher
    ..Most O antigens of Shigella flexneri, a cause of shigellosis, share a backbone composed of ?2)-?-l-Rhap(III)-(1?2)-?-l-Rhap(II)-(..
  25. Apicella M, Post D, Fowler A, Jones B, Rasmussen J, Hunt J, et al. Identification, characterization and immunogenicity of an O-antigen capsular polysaccharide of Francisella tularensis. PLoS ONE. 2010;5:e11060 pubmed publisher
    ..tularensis LVS. Active immunization of BALB/c mice with 10 microg of capsule showed a similar level of protection. These studies demonstrate that F. tularensis produces an O-antigen capsule that may be the basis of a future vaccine...
  26. Hong Y, Cunneen M, Reeves P. The Wzx translocases for Salmonella enterica O-antigen processing have unexpected serotype specificity. Mol Microbiol. 2012;84:620-30 pubmed publisher
    ..widely thought to be specific only for the first sugar of the repeat unit, despite extensive variation in both O antigens and Wzx translocases. However, we found for S...
  27. Papadopoulos M, Morona R. Mutagenesis and chemical cross-linking suggest that Wzz dimer stability and oligomerization affect lipopolysaccharide O-antigen modal chain length control. J Bacteriol. 2010;192:3385-93 pubmed publisher
    ..These data suggest that the ability to produce stable dimers may be important in determining Oag modal chain length. ..
  28. Brett P, Burtnick M, Heiss C, Azadi P, DeShazer D, Woods D, et al. Burkholderia thailandensis oacA mutants facilitate the expression of Burkholderia mallei-like O polysaccharides. Infect Immun. 2011;79:961-9 pubmed publisher
    ..thailandensis OPS antigens and that ZT0715 may provide a safe and cost-effective source of B. mallei-like OPS to facilitate the synthesis of glanders subunit vaccine candidates. ..
  29. Kenyon J, De Castro C, Cunneen M, Reeves P, Molinaro A, Holst O, et al. The genetics and structure of the O-specific polysaccharide of Yersinia pseudotuberculosis serotype O:10 and its relationship with Escherichia coli O111 and Salmonella enterica O35. Glycobiology. 2011;21:1131-9 pubmed publisher
    ..pseudotuberculosis O:10, although there is significant conservation of gene order. Within Y. pseudotuberculosis, the O10 structure is most closely related to the O:6 and O:7 structures...
  30. Naka H, Dias G, Thompson C, Dubay C, Thompson F, Crosa J. Complete genome sequence of the marine fish pathogen Vibrio anguillarum harboring the pJM1 virulence plasmid and genomic comparison with other virulent strains of V. anguillarum and V. ordalii. Infect Immun. 2011;79:2889-900 pubmed publisher
    ..Some of them carried potential virulence genes for the biosynthesis of O antigens, hemolysins, and exonucleases as well as others for sugar transport and metabolism...
  31. Browning D, Wells T, França F, Morris F, Sevastsyanovich Y, Bryant J, et al. Laboratory adapted Escherichia coli K-12 becomes a pathogen of Caenorhabditis elegans upon restoration of O antigen biosynthesis. Mol Microbiol. 2013;87:939-50 pubmed publisher
    ..coli. We show killing is associated with bacterial resistance to mechanical shear and persistence in the C. elegans gut. These results suggest C. elegans is not an effective model of human-pathogenic E. coli infectious disease. ..
  32. Debroy C, Roberts E, Fratamico P. Detection of O antigens in Escherichia coli. Anim Health Res Rev. 2011;12:169-85 pubmed publisher
    Lipopolysaccharide on the surface of Escherichia coli constitutes the O antigens which are important virulence factors that are targets of both the innate and adaptive immune systems and play a major role in host-pathogen interactions...
  33. Kim T, Pinkham J, Heninger S, Chalabaev S, Kasper D. Genetic modification of the O-polysaccharide of Francisella tularensis results in an avirulent live attenuated vaccine. J Infect Dis. 2012;205:1056-65 pubmed publisher
    ..Francisella tularensis, the causative agent of tularemia, is a highly virulent microbe. One significant virulence factor of F. tularensis is the O-polysaccharide (O-PS) portion of the organism's lipopolysaccharide...
  34. Marolda C, Tatar L, Alaimo C, Aebi M, Valvano M. Interplay of the Wzx translocase and the corresponding polymerase and chain length regulator proteins in the translocation and periplasmic assembly of lipopolysaccharide o antigen. J Bacteriol. 2006;188:5124-35 pubmed
  35. Zych K, Perepelov A, Siwińska M, Knirel Y, Sidorczyk Z. Structures of the O-polysaccharides and classification of Proteus genomospecies 4, 5 and 6 into respective Proteus serogroups. FEBS J. 2005;272:5536-43 pubmed
    ..Structural and serological investigations showed that Proteus genomospecies 5 and 6 should be classified into the existing Proteus serogroups O8 and O69, respectively...
  36. Santander J, Wanda S, Nickerson C, Curtiss R. Role of RpoS in fine-tuning the synthesis of Vi capsular polysaccharide in Salmonella enterica serotype Typhi. Infect Immun. 2007;75:1382-92 pubmed
    ..Our results show that RpoS is another regulator of Vi polysaccharide synthesis and contributes to VW variation in serotype Typhi, which has implications for the development of recombinant attenuated Salmonella vaccines in humans. ..
  37. Thomas R, Titball R, Oyston P, Griffin K, Waters E, Hitchen P, et al. The immunologically distinct O antigens from Francisella tularensis subspecies tularensis and Francisella novicida are both virulence determinants and protective antigens. Infect Immun. 2007;75:371-8 pubmed
    ..The O antigen of F. tularensis subsp. tularensis appeared to be important for intracellular survival whereas the O antigen of F. novicida appeared to be critical for serum resistance and less important for intracellular survival...
  38. Jimenez N, Canals R, Lacasta A, Kondakova A, Lindner B, Knirel Y, et al. Molecular analysis of three Aeromonas hydrophila AH-3 (serotype O34) lipopolysaccharide core biosynthesis gene clusters. J Bacteriol. 2008;190:3176-84 pubmed publisher
    ..Having the functions of all genes involved with the LPS core biosynthesis and most corresponding single-gene mutants now allows experimental work on the role of the LPS core in the virulence of A. hydrophila. ..
  39. Lundborg M, Modhukur V, Widmalm G. Glycosyltransferase functions of E. coli O-antigens. Glycobiology. 2010;20:366-8 pubmed publisher
    ..The procedure suggests a novel way of combining genetic information with experimental techniques in structural analysis of oligo- and polysaccharides. ..
  40. Augustin D, Song Y, Baek M, Sawa Y, Singh G, Taylor B, et al. Presence or absence of lipopolysaccharide O antigens affects type III secretion by Pseudomonas aeruginosa. J Bacteriol. 2007;189:2203-9 pubmed
    ..These results suggest the existence of a cooperative association between LPS O-antigen structure and the TTSS in both laboratory and clinical isolates of P. aeruginosa. ..
  41. Meredith T, Mamat U, Kaczynski Z, Lindner B, Holst O, Woodard R. Modification of lipopolysaccharide with colanic acid (M-antigen) repeats in Escherichia coli. J Biol Chem. 2007;282:7790-8 pubmed
    ..The identification of MLPS has implications for potential underlying mechanisms coordinating the synthesis of various surface polysaccharides. ..
  42. Debroy C, Fratamico P, Roberts E, Davis M, Liu Y. Development of PCR assays targeting genes in O-antigen gene clusters for detection and identification of Escherichia coli O45 and O55 serogroups. Appl Environ Microbiol. 2005;71:4919-24 pubmed
    ..coli O55 wzx and wzy genes were used to detect the organisms in fecal samples spiked at levels of 10(6) and 10(8) CFU/0.2 g feces. Thus, the PCR assays can be used to detect and identify E. coli serogroups O45 and O55. ..
  43. Power P, Seib K, Jennings M. Pilin glycosylation in Neisseria meningitidis occurs by a similar pathway to wzy-dependent O-antigen biosynthesis in Escherichia coli. Biochem Biophys Res Commun. 2006;347:904-8 pubmed
    ..meningitidis. PglL mutants showed no change in LPS phenotypes but did show loss of pilin glycosylation, confirming PglL is essential for pilin O-linked glycosylation in N. meningitidis. ..
  44. King J, Mulrooney E, Vinogradov E, Kneidinger B, Mead K, Lam J. lfnA from Pseudomonas aeruginosa O12 and wbuX from Escherichia coli O145 encode membrane-associated proteins and are required for expression of 2,6-dideoxy-2-acetamidino-L-galactose in lipopolysaccharide O antigen. J Bacteriol. 2008;190:1671-9 pubmed
    ..only in bacteria and is a component of cell surface glycans in a number of pathogenic species, including the O antigens of Pseudomonas aeruginosa serotype O12 and Escherichia coli O145. P...
  45. Perepelov A, Li D, Liu B, Senchenkova S, Guo D, Shevelev S, et al. Structural and genetic characterization of Escherichia coli O99 antigen. FEMS Immunol Med Microbiol. 2009;57:80-7 pubmed publisher
    ..Our findings indicate that in E. coli O99, the synthesis and translocation of the O-antigen occurs by an ABC transporter-dependent process. ..
  46. Murray G, Attridge S, Morona R. Altering the length of the lipopolysaccharide O antigen has an impact on the interaction of Salmonella enterica serovar Typhimurium with macrophages and complement. J Bacteriol. 2006;188:2735-9 pubmed
    ..No evidence was found to suggest that modifying the length of the O-antigen polymer affected expression of the O1, O4, or O5 antigenic factors. ..
  47. Bogomolnaya L, Santiviago C, Yang H, BAUMLER A, Andrews Polymenis H. 'Form variation' of the O12 antigen is critical for persistence of Salmonella Typhimurium in the murine intestine. Mol Microbiol. 2008;70:1105-19 pubmed publisher
    ..Our data suggest that the 12-2 antigen is a S. enterica subspecies I-specific LPS modification that enhances long-term intestinal colonization, and is in contrast to the role of O-antigen variation described for Shigella...
  48. King J, Vinogradov E, Preston A, Li J, Maskell D. Post-assembly modification of Bordetella bronchiseptica O polysaccharide by a novel periplasmic enzyme encoded by wbmE. J Biol Chem. 2009;284:1474-83 pubmed publisher
  49. Phalipon A, Costachel C, Grandjean C, Thuizat A, Guerreiro C, Tanguy M, et al. Characterization of functional oligosaccharide mimics of the Shigella flexneri serotype 2a O-antigen: implications for the development of a chemically defined glycoconjugate vaccine. J Immunol. 2006;176:1686-94 pubmed
    ..A pentadecasaccharide representing three biological repeating units was identified as a potential candidate for further development of a chemically defined glycoconjugate vaccine against S. flexneri 2a infection...
  50. Eder K, Vizler C, Kusz E, Karcagi I, Glavinas H, Balogh G, et al. The role of lipopolysaccharide moieties in macrophage response to Escherichia coli. Biochem Biophys Res Commun. 2009;389:46-51 pubmed publisher
    ..The most ancient part, lipid A is crucial in evoking immediate TNF release and activation of NF-kappaB. The O-antigen inhibits phagocytosis, leading to immune evasion. ..
  51. Hölzer S, Schlumberger M, Jäckel D, Hensel M. Effect of the O-antigen length of lipopolysaccharide on the functions of Type III secretion systems in Salmonella enterica. Infect Immun. 2009;77:5458-70 pubmed publisher
    ..These observations indicate that the architecture of the outer membrane of Salmonella is balanced to permit sufficient T3SS function but also to confer optimal protection against antimicrobial defense mechanisms. ..
  52. Thanweer F, Tahiliani V, Korres H, Verma N. Topology and identification of critical residues of the O-acetyltransferase of serotype-converting bacteriophage, SF6, of Shigella flexneri. Biochem Biophys Res Commun. 2008;375:581-5 pubmed publisher
    ..Functionally important cytoplasmic and periplasmic loops have also been identified. Furthermore, cytoplasmic residues R73 and R75R76 were found to be critical to Oac function. ..
  53. Sebastian S, Dillon S, Lynch J, Blalock L, Balon E, Lee K, et al. A defined O-antigen polysaccharide mutant of Francisella tularensis live vaccine strain has attenuated virulence while retaining its protective capacity. Infect Immun. 2007;75:2591-602 pubmed
    ..tularensis type B. Recognition and characterization of the pivotal role of O-PS in the virulence of this intracellular bacterial pathogen may have broad implications for the creation of a safe and efficacious vaccine. ..