C Whitfield

Summary

Affiliation: University of Guelph
Country: Canada

Publications

  1. ncbi request reprint Molecular insights into the assembly and diversity of the outer core oligosaccharide in lipopolysaccharides from Escherichia coli and Salmonella
    Chris Whitfield
    Department of Microbiology, University of Guelph, Guelph, Ontario, Canada
    J Endotoxin Res 9:244-9. 2003
  2. ncbi request reprint Investigation of the structural requirements in the lipopolysaccharide core acceptor for ligation of O antigens in the genus Salmonella: WaaL "ligase" is not the sole determinant of acceptor specificity
    Natalia A Kaniuk
    Department of Microbiology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    J Biol Chem 279:36470-80. 2004
  3. ncbi request reprint The role of galacturonic acid in outer membrane stability in Klebsiella pneumoniae
    Emilisa Frirdich
    Department of Molecular and Cellular Biology, University of Guelph, Guelph Ontario N1G 2W1, Canada
    J Biol Chem 280:27604-12. 2005
  4. ncbi request reprint Biosynthesis and assembly of Group 1 capsular polysaccharides in Escherichia coli and related extracellular polysaccharides in other bacteria
    Chris Whitfield
    Department of Microbiology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
    Carbohydr Res 338:2491-502. 2003
  5. ncbi request reprint Biosynthesis and assembly of capsular polysaccharides in Escherichia coli
    Chris Whitfield
    Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    Annu Rev Biochem 75:39-68. 2006
  6. pmc Periplasmic export machines for outer membrane assembly
    Chris Whitfield
    Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
    Curr Opin Struct Biol 18:466-74. 2008
  7. ncbi request reprint Structure, assembly and regulation of expression of capsules in Escherichia coli
    C Whitfield
    Department of Microbiology, University of Guelph, Ontario, Canada
    Mol Microbiol 31:1307-19. 1999
  8. ncbi request reprint Gene products required for surface expression of the capsular form of the group 1 K antigen in Escherichia coli (O9a:K30)
    J Drummelsmith
    Department of Microbiology, University of Guelph, Ontario, Canada
    Mol Microbiol 31:1321-32. 1999
  9. ncbi request reprint Molecular and functional analysis of genes required for expression of group IB K antigens in Escherichia coli: characterization of the his-region containing gene clusters for multiple cell-surface polysaccharides
    P A Amor
    Department of Microbiology, University of Guelph, Ontario, Canada
    Mol Microbiol 26:145-61. 1997
  10. pmc Characterization of rcsB and rcsC from Escherichia coli O9:K30:H12 and examination of the role of the rcs regulatory system in expression of group I capsular polysaccharides
    P Jayaratne
    Department of Microbiology, University of Guelph, Ontario, Canada
    J Bacteriol 175:5384-94. 1993

Collaborators

Detail Information

Publications65

  1. ncbi request reprint Molecular insights into the assembly and diversity of the outer core oligosaccharide in lipopolysaccharides from Escherichia coli and Salmonella
    Chris Whitfield
    Department of Microbiology, University of Guelph, Guelph, Ontario, Canada
    J Endotoxin Res 9:244-9. 2003
    ..Surveys of waa-locus organization have established the distribution of these core types in natural populations and have identified genetic variants that provide candidates for additional novel structures...
  2. ncbi request reprint Investigation of the structural requirements in the lipopolysaccharide core acceptor for ligation of O antigens in the genus Salmonella: WaaL "ligase" is not the sole determinant of acceptor specificity
    Natalia A Kaniuk
    Department of Microbiology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    J Biol Chem 279:36470-80. 2004
    ..The data provide the first indication of a more complicated recognition process involving additional cellular components...
  3. ncbi request reprint The role of galacturonic acid in outer membrane stability in Klebsiella pneumoniae
    Emilisa Frirdich
    Department of Molecular and Cellular Biology, University of Guelph, Guelph Ontario N1G 2W1, Canada
    J Biol Chem 280:27604-12. 2005
    ..coli and Salmonella...
  4. ncbi request reprint Biosynthesis and assembly of Group 1 capsular polysaccharides in Escherichia coli and related extracellular polysaccharides in other bacteria
    Chris Whitfield
    Department of Microbiology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
    Carbohydr Res 338:2491-502. 2003
    ..Escherichia coli has provided important model systems for EPS and CPS biosynthesis. Here we describe current knowledge concerning assembly of the Group 1 CPSs of E. coli and the conservation of similar mechanisms in other bacteria...
  5. ncbi request reprint Biosynthesis and assembly of capsular polysaccharides in Escherichia coli
    Chris Whitfield
    Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    Annu Rev Biochem 75:39-68. 2006
    ..These systems have an impact on both a general understanding of membrane trafficking in bacteria and on bacterial pathogenesis...
  6. pmc Periplasmic export machines for outer membrane assembly
    Chris Whitfield
    Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
    Curr Opin Struct Biol 18:466-74. 2008
    ..New structural and biochemical information identifies an envelope-spanning molecular scaffold for the export of group 1 capsular polysaccharides and provides insight into a complex molecular machine...
  7. ncbi request reprint Structure, assembly and regulation of expression of capsules in Escherichia coli
    C Whitfield
    Department of Microbiology, University of Guelph, Ontario, Canada
    Mol Microbiol 31:1307-19. 1999
    ..coli into four distinct groups...
  8. ncbi request reprint Gene products required for surface expression of the capsular form of the group 1 K antigen in Escherichia coli (O9a:K30)
    J Drummelsmith
    Department of Microbiology, University of Guelph, Ontario, Canada
    Mol Microbiol 31:1321-32. 1999
    ..These surface expression components provide the key feature that distinguishes the assembly systems for O antigens and capsules...
  9. ncbi request reprint Molecular and functional analysis of genes required for expression of group IB K antigens in Escherichia coli: characterization of the his-region containing gene clusters for multiple cell-surface polysaccharides
    P A Amor
    Department of Microbiology, University of Guelph, Ontario, Canada
    Mol Microbiol 26:145-61. 1997
    ..Thus, rfbK40 is in the location occupied by other Wzy-dependent rfb gene clusters, and rfbO8/O9 represents an additional locus...
  10. pmc Characterization of rcsB and rcsC from Escherichia coli O9:K30:H12 and examination of the role of the rcs regulatory system in expression of group I capsular polysaccharides
    P Jayaratne
    Department of Microbiology, University of Guelph, Ontario, Canada
    J Bacteriol 175:5384-94. 1993
    ..Group IB capsular polysaccharides all contain amino sugars. In group IB strains, multicopy rcsBK30 activates synthesis of colanic acid...
  11. ncbi request reprint Phosphorylation of Wzc, a tyrosine autokinase, is essential for assembly of group 1 capsular polysaccharides in Escherichia coli
    T Wugeditsch
    Department of Microbiology, University of Guelph, Guelph, Ontario, N1G 2W1 Canada
    J Biol Chem 276:2361-71. 2001
    ..Regulation by a post-translational phosphorylation event represents a new dimension in the assembly of bacterial cell-surface polysaccharides...
  12. ncbi request reprint Involvement of waaY, waaQ, and waaP in the modification of Escherichia coli lipopolysaccharide and their role in the formation of a stable outer membrane
    J A Yethon
    Department of Microbiology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    J Biol Chem 273:26310-6. 1998
    ..Only mutation of waaP resulted in hypersensitivity to novobiocin and sodium dodecyl sulfate, a characteristic of deep-rough mutations...
  13. pmc Cloning and analysis of duplicated rfbM and rfbK genes involved in the formation of GDP-mannose in Escherichia coli O9:K30 and participation of rfb genes in the synthesis of the group I K30 capsular polysaccharide
    P Jayaratne
    Department of Microbiology, University of Guelph, Ontario, Canada
    J Bacteriol 176:3126-39. 1994
    ..coli O9:K30. Analysis of a collection of serotype O8 and O9 isolates by Southern hybridization and PCR amplification experiments demonstrated extensive polymorphism in the rfbM-rfbK region...
  14. ncbi request reprint Modulation of the surface architecture of gram-negative bacteria by the action of surface polymer:lipid A-core ligase and by determinants of polymer chain length
    C Whitfield
    Department of Microbiology, University of Guelph, Ontario, Canada
    Mol Microbiol 23:629-38. 1997
    ..Emphasis is placed on the Enterobacteriaceae, but similarities to other bacteria suggest that aspects of the enterobacterial system will have broader significance...
  15. ncbi request reprint The assembly system for the lipopolysaccharide R2 core-type of Escherichia coli is a hybrid of those found in Escherichia coli K-12 and Salmonella enterica. Structure and function of the R2 WaaK and WaaL homologs
    D E Heinrichs
    Department of Microbiology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
    J Biol Chem 273:8849-59. 1998
    ..Results of complementation analyses of E. coli K-12 and F632 waaL mutants suggest that structural differences between the WaaL proteins play a role in recognition of, and interaction with, terminal lipopolysaccharide core moieties...
  16. ncbi request reprint Molecular basis for structural diversity in the core regions of the lipopolysaccharides of Escherichia coli and Salmonella enterica
    D E Heinrichs
    Department of Microbiology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    Mol Microbiol 30:221-32. 1998
    ....
  17. pmc Mutation of the lipopolysaccharide core glycosyltransferase encoded by waaG destabilizes the outer membrane of Escherichia coli by interfering with core phosphorylation
    J A Yethon
    Canadian Bacterial Diseases Network and Department of Microbiology, University of Guelph, Guelph, Ontario N1G 2W1
    J Bacteriol 182:5620-3. 2000
    ..Structural analyses of waaG mutant lipopolysaccharide showed that the cause for this phenotype was a decrease in core phosphorylation, an unexpected side effect of the waaG mutation...
  18. ncbi request reprint Purification and characterization of WaaP from Escherichia coli, a lipopolysaccharide kinase essential for outer membrane stability
    J A Yethon
    Department of Microbiology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    J Biol Chem 276:5498-504. 2001
    ..These data are the first proof that WaaP is indeed an LPS kinase. Further, site-directed mutagenesis of a predicted catalytic residue suggests that WaaP shares a common mechanism of action with eukaryotic protein kinases...
  19. pmc Distribution of the rol gene encoding the regulator of lipopolysaccharide O-chain length in Escherichia coli and its influence on the expression of group I capsular K antigens
    C Dodgson
    Department of Microbiology, University of Guelph, Guelph, Ontario, Canada
    J Bacteriol 178:1895-902. 1996
    ..Collectively, these results suggested that group IA K(LPS) is also synthesized by a Rol-dependent pathway and that the typically short oligosaccharide K(LPS) results from the absence of Rol activity in these strains...
  20. pmc Conserved organization in the cps gene clusters for expression of Escherichia coli group 1 K antigens: relationship to the colanic acid biosynthesis locus and the cps genes from Klebsiella pneumoniae
    A Rahn
    Department of Microbiology, The University of Guelph, Guelph, Ontario, Canada N1G 2W1
    J Bacteriol 181:2307-13. 1999
    ..We propose that the IS elements were responsible for the transfer of the cps locus between organisms and that they may continue to mediate recombination between strains...
  21. pmc Lateral transfer of rfb genes: a mobilizable ColE1-type plasmid carries the rfbO:54 (O:54 antigen biosynthesis) gene cluster from Salmonella enterica serovar Borreze
    W J Keenleyside
    Department of Microbiology, University of Guelph, Ontario, Canada
    J Bacteriol 177:5247-53. 1995
    ..In contrast, the percent G+C value is dramatically lower with rfb0:54, consistent with the possibility that the cluster was acquired from an organism with much lower G+C composition...
  22. pmc Translocation of group 1 capsular polysaccharide to the surface of Escherichia coli requires a multimeric complex in the outer membrane
    J Drummelsmith
    Department of Microbiology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
    EMBO J 19:57-66. 2000
    ..The broad distribution of the OMA protein family suggests a similar process for polysaccharide export in diverse Gram-negative bacteria...
  23. ncbi request reprint A novel pathway for O-polysaccharide biosynthesis in Salmonella enterica serovar Borreze
    W J Keenleyside
    Department of Microbiology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    J Biol Chem 271:28581-92. 1996
    ..Based on sequence and structural conservation, 15 new ExoU-related and 17 new HasA-related transferases were identified...
  24. pmc functional analysis of conserved gene products involved in assembly of Escherichia coli capsules and exopolysaccharides: evidence for molecular recognition between Wza and Wzc for colanic acid biosynthesis
    Anne N Reid
    Department of Molecular and Cellular Biology, New Science Complex, University of Guelph, Guelph, Ontario, Canada N1G 2W1
    J Bacteriol 187:5470-81. 2005
    ..These data highlight the importance of Wza-Wzc interactions in group 1 CPS assembly...
  25. pmc Polymorphism, duplication, and IS1-mediated rearrangement in the chromosomal his-rfb-gnd region of Escherichia coli strains with group IA and capsular K antigens
    J Drummelsmith
    Department of Microbiology, University of Guelph, Ontario, Canada
    J Bacteriol 179:3232-8. 1997
    ..The presence of IS1 elements in the rfb regions of several of these strains provides a potential mechanism for recombination and deletion events which could contribute to the antigenic diversity seen in surface polysaccharides...
  26. ncbi request reprint Translocation of group 1 capsular polysaccharide in Escherichia coli serotype K30. Structural and functional analysis of the outer membrane lipoprotein Wza
    Jutta Nesper
    Department of Microbiology, University of Guelph, Guelph, Ontario N1G2W1, Canada
    J Biol Chem 278:49763-72. 2003
    ..Chemical cross-linking of intact cells suggested formation of a transmembrane complex minimally containing Wza and the inner membrane tyrosine autokinase Wzc...
  27. ncbi request reprint The C-terminal domain of the nucleotide-binding domain protein Wzt determines substrate specificity in the ATP-binding cassette transporter for the lipopolysaccharide O-antigens in Escherichia coli serotypes O8 and O9a
    Leslie Cuthbertson
    Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    J Biol Chem 280:30310-9. 2005
    ..Chimeric Wzt proteins were constructed in order to localize the region involved in substrate specificity to the C-terminal domain...
  28. pmc Functional analysis of the galactosyltransferases required for biosynthesis of D-galactan I, a component of the lipopolysaccharide O1 antigen of Klebsiella pneumoniae
    S Guan
    Department of Microbiology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    J Bacteriol 183:3318-27. 2001
    ..Comparison of the biosynthetic pathways for D-galactan I and the polymannose E. coli O9a antigen reveals some interesting features that may reflect a common theme in ABC transporter-dependent O-PS assembly systems...
  29. pmc The rcsA gene of Escherichia coli O9:K30:H12 is involved in the expression of the serotype-specific group I K (capsular) antigen
    W J Keenleyside
    Department of Microbiology, University of Guelph, Ontario, Canada
    J Bacteriol 174:8-16. 1992
    ....
  30. pmc Structure and functional analysis of LptC, a conserved membrane protein involved in the lipopolysaccharide export pathway in Escherichia coli
    An X Tran
    Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    J Biol Chem 285:33529-39. 2010
    ..Like LptA, LptC binds lipopolysaccharide in vitro. In vitro, LptA can displace lipopolysaccharide from LptC (but not vice versa), consistent with their locations and their proposed placement in a unidirectional export pathway...
  31. pmc Pivotal roles of the outer membrane polysaccharide export and polysaccharide copolymerase protein families in export of extracellular polysaccharides in gram-negative bacteria
    Leslie Cuthbertson
    Department of Molecular and Cellular Biology, University of Guelph, Ontario, Canada N1G 2W1
    Microbiol Mol Biol Rev 73:155-77. 2009
    ..This review is intended as an update on progress in this important area of microbial cell biology...
  32. ncbi request reprint Nonreducing terminal modifications determine the chain length of polymannose O antigens of Escherichia coli and couple chain termination to polymer export via an ATP-binding cassette transporter
    Bradley R Clarke
    Department of Microbiology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    J Biol Chem 279:35709-18. 2004
    ..An E. coli wbdD(O9a) mutant accumulated O9a polymannan in the cytoplasm, indicating that WbdD activity coordinates polymannan chain termination with export across the inner membrane...
  33. pmc Impact of phosphorylation of specific residues in the tyrosine autokinase, Wzc, on its activity in assembly of group 1 capsules in Escherichia coli
    Anne Paiment
    Department of Microbiology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
    J Bacteriol 184:6437-47. 2002
    ..Finally, dithiobis(succinimidylpropionate) cross-linking was used to confirm that Wzc(CPS) forms complexes in vivo, independent of the phosphorylation state of the protein...
  34. ncbi request reprint Lipopolysaccharide as a target for the development of novel therapeutics in gram-negative bacteria
    J A Yethon
    Department of Microbiology, University of Guelph, Guelph, Ontario, N1G 2W1, Canada
    Curr Drug Targets Infect Disord 1:91-106. 2001
    ..This review summarizes the main features of LPS structure, function, and biosynthesis, highlighting the potential target reactions that have been or might be exploited for therapeutic intervention...
  35. pmc A novel outer membrane protein, Wzi, is involved in surface assembly of the Escherichia coli K30 group 1 capsule
    Andrea Rahn
    Department of Microbiology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
    J Bacteriol 185:5882-90. 2003
    ..It is proposed that the Wzi protein plays a late role in capsule assembly, perhaps in the process that links high-molecular-weight capsule to the cell surface...
  36. pmc Biochemical and structural analysis of bacterial O-antigen chain length regulator proteins reveals a conserved quaternary structure
    Kane Larue
    Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    J Biol Chem 284:7395-403. 2009
    ..The data suggest that in vivo Wzz proteins determine O-antigen chain length via subtle structure-function relationships at the level of primary, secondary, or tertiary structure within the context of a hexameric complex...
  37. ncbi request reprint Chromosomal and plasmid-encoded enzymes are required for assembly of the R3-type core oligosaccharide in the lipopolysaccharide of Escherichia coli O157:H7
    Natalia A Kaniuk
    Department of Microbiology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    J Biol Chem 279:31237-50. 2004
    ..coli O157 and Shigella flexneri serotype 2a. This is the first plasmid-encoded core oligosaccharide biosynthesis enzyme reported in E. coli...
  38. ncbi request reprint Biosynthesis of a novel 3-deoxy-D-manno-oct-2-ulosonic acid-containing outer core oligosaccharide in the lipopolysaccharide of Klebsiella pneumoniae
    Emilisa Frirdich
    Department of Microbiology, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1, Canada
    J Biol Chem 279:27928-40. 2004
    ..The activated precursor required for GlcN addition has not been identified. However, lysates overexpressing WabH were able to transfer a GlcNAc residue from UDP-GlcNAc onto the acceptor GalUA residue in the outer core...
  39. pmc A membrane-located glycosyltransferase complex required for biosynthesis of the D-galactan I lipopolysaccharide O antigen in Klebsiella pneumoniae
    Veronica Kos
    Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    J Biol Chem 285:19668-87. 2010
    ....
  40. pmc Overexpression of the waaZ gene leads to modification of the structure of the inner core region of Escherichia coli lipopolysaccharide, truncation of the outer core, and reduction of the amount of O polysaccharide on the cell surface
    Emilisa Frirdich
    Department of Microbiology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    J Bacteriol 185:1659-71. 2003
    ..Novel truncated LPS structures, lacking up to 3 hexoses from the outer core, resulted from WaaZ overexpression. The truncated molecules also contained a KdoIII residue not normally found in the R1 core...
  41. pmc Coordination of polymerization, chain termination, and export in assembly of the Escherichia coli lipopolysaccharide O9a antigen in an ATP-binding cassette transporter-dependent pathway
    Bradley R Clarke
    Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    J Biol Chem 284:30662-72. 2009
    ..Therefore, in the O9a assembly export system, the WbdD protein orchestrates the critical localization and coordination of activities involved in O-PS chain extension and termination at the cytoplasmic membrane...
  42. ncbi request reprint Glycosyltransferases involved in biosynthesis of the outer core region of Escherichia coli lipopolysaccharides exhibit broader substrate specificities than is predicted from lipopolysaccharide structures
    Michael D Leipold
    Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
    J Biol Chem 282:26786-92. 2007
    ..These results illustrate the differences in behavior between closely related glycosyltransferase enzymes involved in the synthesis of similar glycoconjugates and have implications for glycoengineering applications...
  43. pmc Substrate binding by a bacterial ABC transporter involved in polysaccharide export
    Leslie Cuthbertson
    Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
    Proc Natl Acad Sci U S A 104:19529-34. 2007
    ..Elucidation of the substrate-recognition system involved in O-PS export provides insight into the mechanism that coordinates polymer biosynthesis, termination, and export...
  44. ncbi request reprint Molecular diversity of the genetic loci responsible for lipopolysaccharide core oligosaccharide assembly within the genus Salmonella
    Natalia A Kaniuk
    Department of Microbiology, University of Guelph, Guelph, ON, Canada, N1G 2W1
    Mol Microbiol 46:1305-18. 2002
    ....
  45. pmc Comparative analysis of flagellin sequences from Escherichia coli strains possessing serologically distinct flagellar filaments with a shared complex surface pattern
    G Schoenhals
    Department of Microbiology, College of Biological Sciences, University of Guelph, Ontario, Canada
    J Bacteriol 175:5395-402. 1993
    ..Comparison of morphotype E E. coli flagellins with those from E. coli K-12, Serratia marcescens, and several Salmonella serovars supported the established concept of highly conserved terminal regions flanking a variable central region...
  46. doi request reprint The Klebsiella pneumoniae O2a antigen defines a second mechanism for O antigen ATP-binding cassette transporters
    Veronica Kos
    Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
    J Biol Chem 284:2947-56. 2009
    ..This study establishes that two distinctly different approaches are available for the regulation of O antigen chain length and export via an ABC transporter...
  47. pmc The LptA protein of Escherichia coli is a periplasmic lipid A-binding protein involved in the lipopolysaccharide export pathway
    An X Tran
    Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
    J Biol Chem 283:20342-9. 2008
    ..These results are consistent with LptA playing a chaperone role in the transport of LPS across the periplasm and have implications for possible assembly models...
  48. ncbi request reprint Transcriptional organization and regulation of the Escherichia coli K30 group 1 capsule biosynthesis (cps) gene cluster
    Andrea Rahn
    Department of Microbiology, University of Guelph, Guelph, ON, Canada, N1G 2W1
    Mol Microbiol 47:1045-60. 2003
    ..However, the Rcs system can potentially influence levels of capsular polysaccharide production by increasing galF transcription and influencing the available pool of biosynthetic precursors...
  49. ncbi request reprint The C-terminal Domain of the Escherichia coli WaaJ glycosyltransferase is important for catalytic activity and membrane association
    Michael D Leipold
    Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
    J Biol Chem 282:1257-64. 2007
    ..Deletions removing 20 or more residues resulted in a protein showing no detectable in vitro activity. Therefore, the C-terminal domain of WaaJ plays a critical role in enzyme function...
  50. pmc ABC transporters involved in export of cell surface glycoconjugates
    Leslie Cuthbertson
    Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
    Microbiol Mol Biol Rev 74:341-62. 2010
    ..The familial relationships among the ABC exporters generate hypotheses concerning the biosynthesis of structurally diverse oligo- and polysaccharides, which play important roles in the biology of bacteria with different lifestyles...
  51. ncbi request reprint Lipopolysaccharide inner core oligosaccharide structure and outer membrane stability in human pathogens belonging to the Enterobacteriaceae
    Emilisa Frirdich
    Department of Microbiology, University of Guelph, Ontario, Canada
    J Endotoxin Res 11:133-44. 2005
    ..However, the biological role(s) of the remaining substitutions is unknown...
  52. pmc Wza the translocon for E. coli capsular polysaccharides defines a new class of membrane protein
    Changjiang Dong
    Centre for Biomolecular Sciences, The University of St Andrews, Fife KY16 9RH, UK
    Nature 444:226-9. 2006
    ..We propose a route and mechanism for translocation of the capsular polysaccharide. This work may provide insight into the export of other large polar molecules such as DNA and proteins...
  53. ncbi request reprint Crystallization and preliminary X-ray diffraction analysis of Wza outer-membrane lipoprotein from Escherichia coli serotype O9a:K30
    Konstantinos Beis
    Centre for Biomolecular Sciences, University of St Andrews, North Haugh, St Andrews, Fife KY16 9ST, Scotland
    Acta Crystallogr D Biol Crystallogr 60:558-60. 2004
    ..6, b = 215.5, c = 218.5 A. A data set to 3.0 A with 99.8% completeness and an R(merge) of 10.5% has been collected from a single crystal...
  54. ncbi request reprint Three-dimensional structure of Wza, the protein required for translocation of group 1 capsular polysaccharide across the outer membrane of Escherichia coli
    Konstantinos Beis
    Centre for Biomolecular Sciences, University of St Andrews, North Haugh, St Andrews, Fife KY16 9ST, Scotland, United Kingdom
    J Biol Chem 279:28227-32. 2004
    ..We discuss the structure of this complex and implications in the surface translocation of cell-surface polysaccharide...
  55. pmc Functional expression of enterobacterial O-polysaccharide biosynthesis enzymes in Bacillus subtilis
    Christina Schäffer
    Zentrum für Ultrastrukturforschung and Ludwig Boltzmann Institut für Molekulare Nanotechnologie, Universitat fur Bodenkultur Wien, A 1180 Vienna, Austria
    Appl Environ Microbiol 68:4722-30. 2002
    ..Enzyme activities in B. subtilis varied between 20 and 75% of those measured in E. coli...
  56. pmc Lipopolysaccharide endotoxins
    Christian R H Raetz
    Department of Biochemistry, Duke University Medical Center, Durham, North Carolina 27710, USA
    Annu Rev Biochem 71:635-700. 2002
    ..The expanding knowledge of TLR4 specificity and its downstream signaling pathways should provide new opportunities for blocking inflammation associated with infection...
  57. pmc Periplasmic protein-protein contacts in the inner membrane protein Wzc form a tetrameric complex required for the assembly of Escherichia coli group 1 capsules
    Richard F Collins
    Faculty of Life Science, University of Manchester, Manchester M60 1QD, United Kingdom
    J Biol Chem 281:2144-50. 2006
    ..We propose that the crown is formed by protein-protein contacts from the four Wzc periplasmic domains, while each root represents an individual cytoplasmic tyrosine autokinase domain...
  58. pmc Two-step purification of outer membrane proteins
    Konstantinos Beis
    Centre for Biomolecular Sciences, University of St Andrews, St Andrews, Fife KY16 9ST, UK
    Int J Biol Macromol 39:10-4. 2006
    ..5 mg for the Wza protein and 291.5 mg for the OmpC protein. The purity of the samples was judged by electrophoretic analysis, mass spectrometry, single particle analysis, three-dimensional (3D) crystallisation and X-ray diffraction...
  59. pmc Substrate specificity of bacterial oligosaccharyltransferase suggests a common transfer mechanism for the bacterial and eukaryotic systems
    Michael Wacker
    Institute of Microbiology, Department of Biology, Swiss Federal Institute of Technology, CH 8093 Zurich, Switzerland
    Proc Natl Acad Sci U S A 103:7088-93. 2006
    ..jejuni glycosylation system into S. enterica. The elucidation of the mechanism of action and the substrate specificity of PglB represents the foundation for engineering glycoproteins that will have an impact on biotechnology...
  60. pmc The 3D structure of a periplasm-spanning platform required for assembly of group 1 capsular polysaccharides in Escherichia coli
    Richard F Collins
    Faculty of Life Science, University of Manchester, Manchester M60 1QD, United Kingdom
    Proc Natl Acad Sci U S A 104:2390-5. 2007
    ..We propose that the Wza-Wzc complex provides the structural and regulatory core of a larger macromolecular machine. We suggest a mechanism by which CPS may move from the periplasm through the outer membrane...
  61. pmc Functional characterization of the initiation enzyme of S-layer glycoprotein glycan biosynthesis in Geobacillus stearothermophilus NRS 2004/3a
    Kerstin Steiner
    Zentrum für NanoBiotechnologie, Universitat fur Bodenkultur Wien, A 1180 Wien, Austria
    J Bacteriol 189:2590-8. 2007
    ..To confirm the function of the enzyme, we show that WsaP is capable of reconstituting polysaccharide biosynthesis in WbaP-deficient strains of Escherichia coli and Salmonella enterica serovar Typhimurium...
  62. doi request reprint Stop and go: regulation of chain length in the biosynthesis of bacterial polysaccharides
    Chris Whitfield
    Nat Struct Mol Biol 15:121-3. 2008
  63. ncbi request reprint Toward a structural understanding of the dehydratase mechanism
    Simon T M Allard
    Centre for Biomolecular Sciences, North Haugh, The University, St Andrews, Fife KY16 9ST, Scotland, United Kingdom
    Structure 10:81-92. 2002
    ..We conclude that the substrate is required to move within the active site to complete the catalytic cycle and that this movement is driven by the elimination of water. The results provide insight into members of the SDR superfamily...
  64. pmc The Klebsiella pneumoniae O antigen contributes to bacteremia and lethality during murine pneumonia
    Sunita Shankar-Sinha
    Department of Emergency Medicine, School of Medicine, University of Michigan, Ann Arbor, Michigan, USA
    Infect Immun 72:1423-30. 2004
    ..These results suggest that during murine pneumonia caused by K. pneumoniae, O antigen contributes to lethality by increasing the propensity for bacteremia and not by significantly changing the early course of intrapulmonary infection...
  65. ncbi request reprint Structures of lipopolysaccharides from Klebsiella pneumoniae. Eluicidation of the structure of the linkage region between core and polysaccharide O chain and identification of the residues at the non-reducing termini of the O chains
    Evgeny Vinogradov
    Institute for Biological Sciences, National Research Council, Ottawa, Ontario K1A 0R6, Canada
    J Biol Chem 277:25070-81. 2002
    ..All serotypes had an identical linkage between the O chain and core...