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

Novel Sialic Acid Transporter of Haemophilus influenzae

Buck Institute for Age Research, 8001 Redwood Blvd., Novato, California 94945,¹ Department of Microbiology, University of Iowa, Iowa City, Iowa 52242,² Department of Pharmaceutical Chemistry, University of California, San Francisco, California 94143-0446³

Received 7 February 2005/ Returned for modification 30 March 2005/ Accepted 24 May 2005

Nontypeable Haemophilus influenzae is an opportunistic pathogen and a common cause of otitis media in children and of chronic bronchitis and pneumonia in patients with chronic obstructive pulmonary disease. The lipooligosaccharides, a major component of the outer membrane of H. influenzae, play an important role in microbial virulence and pathogenicity. N-Acetylneuraminic acid (sialic acid) can be incorporated into the lipooligosaccharides as a terminal nonreducing sugar. Although much of the pathway of sialic acid incorporation into lipooligosaccharides is understood, the transporter responsible for N-acetylneuraminic acid uptake in H. influenzae has yet to be characterized. In this paper we demonstrate that this transporter is a novel sugar transporter of the tripartite ATP-independent periplasmic transporter family. In the absence of this transporter, H. influenzae cannot incorporate sialic acid into its lipooligosaccharides, making the organism unable to survive when exposed to human serum and causing reduced viability in biofilm growth.

Supplemental material for this article may be found at http://iai.asm.org/.

Editor: J. N. Weiser

This article has been cited by other articles:

• Severi, E., Muller, A., Potts, J. R., Leech, A., Williamson, D., Wilson, K. S., Thomas, G. H. (2008). Sialic Acid Mutarotation Is Catalyzed by the Escherichia coli {beta}-Propeller Protein YjhT. J. Biol. Chem. 283: 4841-4849 [Abstract] [Full Text]  
• Johnston, J. W., Coussens, N. P., Allen, S., Houtman, J. C. D., Turner, K. H., Zaleski, A., Ramaswamy, S., Gibson, B. W., Apicella, M. A. (2008). Characterization of the N-Acetyl-5-neuraminic Acid-binding Site of the Extracytoplasmic Solute Receptor (SiaP) of Nontypeable Haemophilus influenzae Strain 2019. J. Biol. Chem. 283: 855-865 [Abstract] [Full Text]  
• Severi, E., Hood, D. W., Thomas, G. H. (2007). Sialic acid utilization by bacterial pathogens. Microbiology 153: 2817-2822 [Abstract] [Full Text]  
• Erwin, A. L., Allen, S., Ho, D. K., Bonthius, P. J., Jarisch, J., Nelson, K. L., Tsao, D. L., Unrath, W. C. T., Watson, M. E. Jr., Gibson, B. W., Apicella, M. A., Smith, A. L. (2006). Role of lgtC in Resistance of Nontypeable Haemophilus influenzae Strain R2866 to Human Serum. Infect. Immun. 74: 6226-6235 [Abstract] [Full Text]  
• Muller, A., Severi, E., Mulligan, C., Watts, A. G., Kelly, D. J., Wilson, K. S., Wilkinson, A. J., Thomas, G. H. (2006). Conservation of Structure and Mechanism in Primary and Secondary Transporters Exemplified by SiaP, a Sialic Acid Binding Virulence Factor from Haemophilus influenzae. J. Biol. Chem. 281: 22212-22222 [Abstract] [Full Text]  
• Thomas, G. H., Southworth, T., Leon-Kempis, M. R., Leech, A., Kelly, D. J. (2006). Novel ligands for the extracellular solute receptors of two bacterial TRAP transporters. Microbiology 152: 187-198 [Abstract] [Full Text]