This Article Full Text (PDF) 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 Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Currie, H. L. Articles by Lam, J. S. Search for Related Content PubMed PubMed Citation Articles by Currie, H. L. Articles by Lam, J. S.

 Previous Article  |  Next Article 

Clinical and Diagnostic Laboratory Immunology, 09 1995, 554-562, Vol 2, No. 5
Copyright © 1995 by the American Society for Microbiology. All rights reserved.

Prevalence of gca, a gene involved in synthesis of A-band common antigen polysaccharide in Pseudomonas aeruginosa

HL Currie, J Lightfoot and JS Lam
Canadian Bacterial Diseases Network, Guelph, Ontario, Canada.

Two distinct forms of lipopolysaccharide are expressed by Pseudomonas aeruginosa. These forms are known as the A band and the B band. In an attempt to obtain a better understanding of A-band lipopolysaccharide synthesis, a previously isolated A-band gene known as the gca gene (GDP- D-mannose conversion protein for A-band common antigen polysaccharide) was sequenced and analyzed. Previous protein expression data from our laboratory, along with nucleotide sequence analysis from the present study, suggest that the Gca protein is encoded by the open reading frame ORF36.5. Amino acid homology reveals that this protein may be functioning as a dehydratase or as a bifunctional enzyme, facilitating the conversion of GDP-D-mannose to GDP-D-rhamnose. The distribution of this gca gene among the 20 P. aeruginosa O serotypes, clinical isolates, and other Pseudomonas species was also examined. Southern hybridization results revealed that the gca gene is present and conserved on a 1.6-kb KpnI fragment among all 20 O serotypes with the exception of serotype O12. In addition, the gca gene is not universally found among all pseudomonads; however, probe-reactive profiles are similar to that of P. aeruginosa when the gca gene is present. Primers were designed from the gca nucleotide sequence, and PCR amplification of a 700-bp product was found with each of the 20 O serotypes. Because of the conservation of this gene, gca may be useful as a diagnostic tool for detecting the presence of P. aeruginosa as well as other Pseudomonas species.

This article has been cited by other articles:

• Webb, N. A., Mulichak, A. M., Lam, J. S., Rocchetta, H. L., Garavito, R. M. (2004). Crystal structure of a tetrameric GDP-D-mannose 4,6-dehydratase from a bacterial GDP-D-rhamnose biosynthetic pathway. Protein Sci. 13: 529-539 [Abstract] [Full Text]  
• Awram, P., Smit, J. (2001). Identification of lipopolysaccharide O antigen synthesis genes required for attachment of the S-layer of Caulobacter crescentus. Microbiology 147: 1451-1460 [Abstract] [Full Text]  
• Rocchetta, H. L., Burrows, L. L., Lam, J. S. (1999). Genetics of O-Antigen Biosynthesis in Pseudomonas aeruginosa. Microbiol. Mol. Biol. Rev. 63: 523-553 [Abstract] [Full Text]  
• Awram, P., Smit, J. (1998). . J. Bacteriol. 180: 3062-3069 [Abstract] [Full Text]  
• Ohyama, C., Smith, P. L., Angata, K., Fukuda, M. N., Lowe, J. B., Fukuda, M. (1998). Molecular Cloning and Expression of GDP-D-mannose-4,6-dehydratase, a Key Enzyme for Fucose Metabolism Defective in Lec13 Cells. J. Biol. Chem. 273: 14582-14587 [Abstract] [Full Text]