This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Ram, S.
Right arrow Articles by Rice, P. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Ram, S.
Right arrow Articles by Rice, P. A.

 Previous Article  |  Next Article 

Infection and Immunity, August 2007, p. 4071-4081, Vol. 75, No. 8
0019-9567/07/$08.00+0     doi:10.1128/IAI.01109-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

Heptose I Glycan Substitutions on Neisseria gonorrhoeae Lipooligosaccharide Influence C4b-Binding Protein Binding and Serum Resistance{triangledown}

Sanjay Ram,1* Jutamas Ngampasutadol,1 Andrew D. Cox,2 Anna M. Blom,3 Lisa A. Lewis,1 Frank St. Michael,2 Jacek Stupak,2 Sunita Gulati,1 and Peter A. Rice1

Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, Massachusetts 01605,1 National Research Council, Ottawa, Ontario K1A 0R6, Canada,2 Department of Laboratory Medicine, Section of Medical Protein Chemistry, Wallenberg Laboratory, University Hospital Malmo, Lund University, Malmö, Sweden3

Received 14 July 2006/ Returned for modification 23 August 2006/ Accepted 11 May 2007

Lipooligosaccharide (LOS) heptose (Hep) glycan substitutions influence gonococcal serum resistance. Several gonococcal strains bind the classical complement pathway inhibitor, C4b-binding protein (C4BP), via their porin (Por) molecule to escape complement-dependent killing by normal human serum (NHS). We show that the proximal glucose (Glc) on HepI is required for C4BP binding to Por1B-bearing gonococcal strains MS11 and 1291 but not to FA19 (Por1A). The presence of only the proximal Glc on HepI (lgtE mutant) permitted maximal C4BP binding to MS11 but not to 1291. Replacing 1291 lgtE Por with MS11 Por increased C4BP binding to levels that paralleled MS11 lgtE, suggesting that replacement of the Por1B molecule dictated the effects of HepI glycans on C4BP binding. The remainder of the strain background did not affect C4BP binding; replacing the Por of strain F62 with MS11 Por (F62 PorMS11) and truncating HepI mirrored the findings in the MS11 background. C4BP binding correlated with resistance to killing by NHS in most instances. F62 PorMS11 and its lgtE mutant were sensitive to NHS despite binding C4BP, secondary to kinetically overwhelming classical pathway activation and possibly increased alternative pathway activation (measured by factor Bb binding) by the F62 background. FA19 lgtF (HepI unsubstituted) resisted killing by only 10% NHS, not 50% NHS, despite binding levels of C4BP similar to those of FA19 and FA19 lgtE (both resistant to 50% serum), suggesting a role for the proximal Glc in serum resistance independently of C4BP binding. This study provides mechanistic insights into how HepI LOS substitutions affect the serum resistance of N. gonorrhoeae.


* Corresponding author. Mailing address: Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Lazare Research Building, Room 322, 364 Plantation Street, Worcester, MA 01605. Phone: (508) 856-6269. Fax: (508) 856-5463. E-mail: sanjay.ram{at}umassmed.edu

{triangledown} Published ahead of print on 25 May 2007.

Editor: J. N. Weiser


Infection and Immunity, August 2007, p. 4071-4081, Vol. 75, No. 8
0019-9567/07/$08.00+0     doi:10.1128/IAI.01109-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.




This article has been cited by other articles:

  • Lewis, L. A., Choudhury, B., Balthazar, J. T., Martin, L. E., Ram, S., Rice, P. A., Stephens, D. S., Carlson, R., Shafer, W. M. (2009). Phosphoethanolamine Substitution of Lipid A and Resistance of Neisseria gonorrhoeae to Cationic Antimicrobial Peptides and Complement-Mediated Killing by Normal Human Serum. Infect. Immun. 77: 1112-1120 [Abstract] [Full Text]  
  • Tsai, C.-M., Jankowska-Stephens, E., Mizanur, R. M., Cipollo, J. F. (2009). The Fine Structure of Neisseria meningitidis Lipooligosaccharide from the M986 Strain and Three of Its Variants. J. Biol. Chem. 284: 4616-4625 [Abstract] [Full Text]  
  • Garvin, L. E., Bash, M. C., Keys, C., Warner, D. M., Ram, S., Shafer, W. M., Jerse, A. E. (2008). Phenotypic and Genotypic Analyses of Neisseria gonorrhoeae Isolates That Express Frequently Recovered PorB PIA Variable Region Types Suggest that Certain P1a Porin Sequences Confer a Selective Advantage for Urogenital Tract Infection. Infect. Immun. 76: 3700-3709 [Abstract] [Full Text]  
  • Rosadini, C. V., Wong, S. M. S., Akerley, B. J. (2008). The Periplasmic Disulfide Oxidoreductase DsbA Contributes to Haemophilus influenzae Pathogenesis. Infect. Immun. 76: 1498-1508 [Abstract] [Full Text]