This Article Full Text 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 Nair, S. Articles by Sanderson, K. E. Search for Related Content PubMed PubMed Citation Articles by Nair, S. Articles by Sanderson, K. E.

 Previous Article  |  Next Article 

Journal of Bacteriology, May 2004, p. 3214-3223, Vol. 186, No. 10
0021-9193/04/$08.00+0     DOI: 10.1128/JB.186.10.3214-3223.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.

Salmonella enterica Serovar Typhi Strains from Which SPI7, a 134-Kilobase Island with Genes for Vi Exopolysaccharide and Other Functions, Has Been Deleted

Department of Biological Sciences,¹ Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada T2N 1N4,³ Sidney Kimmel Cancer Center, San Diego, California 92121²

Received 28 November 2003/ Accepted 3 February 2004

Salmonella enterica serovar Typhi has a 134-kb island of DNA identified as salmonella pathogenicity island 7 (SPI7), inserted between pheU and 'pheU (truncated), two genes for tRNA^Phe. SPI7 has genes for Vi exopolysaccharide, for type IVB pili, for putative conjugal transfer, and for sopE bacteriophage. Pulsed-field gel electrophoresis following digestion with the endonuclease I-CeuI, using DNA from a set of 120 wild-type strains of serovar Typhi assembled from several sources, identified eight strains in which the I-CeuI G fragment, which contains SPI7, had a large deletion. In addition, agglutination tests with Vi antiserum and phage typing with Vi phages show that all eight strains are Vi negative. We therefore tested these strains for deletion of SPI7 by multiplex PCR, by microarray analysis, and by sequencing of PCR amplicons. Data show that seven of the eight strains are precise deletions of SPI7: a primer pair flanking SPI7 results in a PCR amplicon containing a single pheU gene; microarrays show that all SPI7 genes are deleted. Two of the strains produce amplicons which have A derived from pheU at bp 27, while five have C derived from 'pheU at this position; thus, the position of the crossover which results in the deletion can be inferred. The deletion in the eighth strain, TYT1669, removes 175 kb with junction points in genes STY4465 and STY4664; the left junction of SPI7 and adjacent genes, as well as part of SPI7 including the viaB operon for Vi exopolysaccharide, was removed, while the right junction of SPI7 was retained. We propose that these deletions occurred during storage following isolation.

This article has been cited by other articles:

• Arrach, N., Porwollik, S., Cheng, P., Cho, A., Long, F., Choi, S.-H., McClelland, M. (2008). Salmonella Serovar Identification Using PCR-Based Detection of Gene Presence and Absence. J. Clin. Microbiol. 46: 2581-2589 [Abstract] [Full Text]  
• Baker, S., Pickard, D., Whitehead, S., Farrar, J., Dougan, G. (2008). Mobilization of the incQ Plasmid R300B with a Chromosomal Conjugation System in Salmonella enterica Serovar Typhi. J. Bacteriol. 190: 4084-4087 [Abstract] [Full Text]  
• Forest, C., Faucher, S. P., Poirier, K., Houle, S., Dozois, C. M., Daigle, F. (2007). Contribution of the stg Fimbrial Operon of Salmonella enterica Serovar Typhi during Interaction with Human Cells. Infect. Immun. 75: 5264-5271 [Abstract] [Full Text]  
• Chandel, D. S., Chaudhry, R., Dey, A. B., Malhotra, P. (2006). Molecular Typing Reveals a Unique Clone of Salmonella enterica Serotype Typhi among Indian Strains.. J. Clin. Microbiol. 44: 2673-2675 [Full Text]  
• Liu, G.-R., Liu, W.-Q., Johnston, R. N., Sanderson, K. E., Li, S.-X., Liu, S.-L. (2006). Genome Plasticity and ori-ter Rebalancing in Salmonella typhi. Mol Biol Evol 23: 365-371 [Abstract] [Full Text]  
• Raffatellu, M., Chessa, D., Wilson, R. P., Tukel, C., Akcelik, M., Baumler, A. J. (2006). Capsule-Mediated Immune Evasion: a New Hypothesis Explaining Aspects of Typhoid Fever Pathogenesis. Infect. Immun. 74: 19-27 [Full Text]  
• Tam, C. K. P., Hackett, J., Morris, C. (2005). Rate of Inversion of the Salmonella enterica Shufflon Regulates Expression of Invertible DNA. Infect. Immun. 73: 5568-5577 [Abstract] [Full Text]  
• Baker, S., Sarwar, Y., Aziz, H., Haque, A., Ali, A., Dougan, G., Wain, J., Haque, A. (2005). Detection of Vi-Negative Salmonella enterica Serovar Typhi in the Peripheral Blood of Patients with Typhoid Fever in the Faisalabad Region of Pakistan. J. Clin. Microbiol. 43: 4418-4425 [Abstract] [Full Text]  
• Faucher, S. P., Curtiss, R. III, Daigle, F. (2005). Selective Capture of Salmonella enterica Serovar Typhi Genes Expressed in Macrophages That Are Absent from the Salmonella enterica Serovar Typhimurium Genome. Infect. Immun. 73: 5217-5221 [Abstract] [Full Text]  
• Wu, K.-Y., Liu, G.-R., Liu, W.-Q., Wang, A. Q., Zhan, S., Sanderson, K. E., Johnston, R. N., Liu, S.-L. (2005). The Genome of Salmonella enterica Serovar Gallinarum: Distinct Insertions/Deletions and Rare Rearrangements. J. Bacteriol. 187: 4720-4727 [Abstract] [Full Text]  
• Kothapalli, S., Nair, S., Alokam, S., Pang, T., Khakhria, R., Woodward, D., Johnson, W., Stocker, B. A. D., Sanderson, K. E., Liu, S.-L. (2005). Diversity of Genome Structure in Salmonella enterica Serovar Typhi Populations. J. Bacteriol. 187: 2638-2650 [Abstract] [Full Text]  
• Wain, J., House, D., Zafar, A., Baker, S., Nair, S., Kidgell, C., Bhutta, Z., Dougan, G., Hasan, R. (2005). Vi Antigen Expression in Salmonella enterica Serovar Typhi Clinical Isolates from Pakistan. J. Clin. Microbiol. 43: 1158-1165 [Abstract] [Full Text]  
• Bueno, S. M., Santiviago, C. A., Murillo, A. A., Fuentes, J. A., Trombert, A. N., Rodas, P. I., Youderian, P., Mora, G. C. (2004). Precise Excision of the Large Pathogenicity Island, SPI7, in Salmonella enterica Serovar Typhi. J. Bacteriol. 186: 3202-3213 [Abstract] [Full Text]