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 Mao, Y.
Right arrow Articles by Chen, J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Mao, Y.
Right arrow Articles by Chen, J.

 Previous Article

Journal of Bacteriology, June 2001, p. 3811-3815, Vol. 183, No. 12
0021-9193/01/$04.00+0   DOI: 10.1128/JB.183.12.3811-3815.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.

Insertion Mutagenesis of wca Reduces Acid and Heat Tolerance of Enterohemorrhagic Escherichia coli O157:H7

Ying Mao, Michael P. Doyle, and Jinru Chen*

Center for Food Safety and Department of Food Science and Technology, University of Georgia, Griffin, Georgia 30223-1797

Received 27 December 2000/Accepted 30 March 2001

Strains of enterohemorrhagic Escherichia coli (EHEC) serotype O157:H7 produce under stress copious amounts of exopolysaccharide (EPS) composed of colanic acid (CA). Studies were performed to evaluate the association of production of CA with survival of EHEC under adverse environmental conditions. A CA-deficient mutant, M4020, was obtained from a CA-proficient parental strain, E. coli O157:H7 W6-13, by inserting a kanamycin resistance gene cassette (kan) into wcaD and wcaE, 2 of the 21 genes required for CA biosynthesis. M4020 was defective in CA production as determined from the ratio of uronic acid to protein (UA/P) of cells grown from 1 to 4 days at 25°C on minimal glucose agar (MGA), MacConkey agar, and sorbitol-MacConkey agar, and by colony morphology on MGA. The results of stress treatment revealed that M4020 was substantially less tolerant to acid (pH 4.5 and 5.5) and heat (55 and 60°C) in comparison to W6-13, indicating that CA confers on E. coli O157:H7 a protective effect from the environmental stresses of acid and heat.


* Corresponding author. Mailing address: Center for Food Safety, University of Georgia, 1109 Experiment St., Griffin, GA 30223-1797. Phone: (770) 412-4738. Fax: (770) 229-3216. E-mail: jchen{at}cfsqe.griffin.peachnet.edu.


Journal of Bacteriology, June 2001, p. 3811-3815, Vol. 183, No. 12
0021-9193/01/$04.00+0   DOI: 10.1128/JB.183.12.3811-3815.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.



This article has been cited by other articles:

  • Lerner, A., Okon, Y., Burdman, S. (2009). The wzm gene located on the pRhico plasmid of Azospirillum brasilense Sp7 is involved in lipopolysaccharide synthesis. Microbiology 155: 791-804 [Abstract] [Full Text]  
  • Ionescu, M., Belkin, S. (2009). Overproduction of Exopolysaccharides by an Escherichia coli K-12 rpoS Mutant in Response to Osmotic Stress. Appl. Environ. Microbiol. 75: 483-492 [Abstract] [Full Text]  
  • Reid, A. N., Pandey, R., Palyada, K., Whitworth, L., Doukhanine, E., Stintzi, A. (2008). Identification of Campylobacter jejuni Genes Contributing to Acid Adaptation by Transcriptional Profiling and Genome-Wide Mutagenesis. Appl. Environ. Microbiol. 74: 1598-1612 [Abstract] [Full Text]  
  • Ahimou, F., Semmens, M. J., Haugstad, G., Novak, P. J. (2007). Effect of Protein, Polysaccharide, and Oxygen Concentration Profiles on Biofilm Cohesiveness. Appl. Environ. Microbiol. 73: 2905-2910 [Abstract] [Full Text]  
  • Reid, A. N., Whitfield, C. (2005). 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. J. Bacteriol. 187: 5470-5481 [Abstract] [Full Text]  
  • John, M., Kudva, I. T., Griffin, R. W., Dodson, A. W., McManus, B., Krastins, B., Sarracino, D., Progulske-Fox, A., Hillman, J. D., Handfield, M., Tarr, P. I., Calderwood, S. B. (2005). Use of In Vivo-Induced Antigen Technology for Identification of Escherichia coli O157:H7 Proteins Expressed during Human Infection. Infect. Immun. 73: 2665-2679 [Abstract] [Full Text]  
  • Li, G., Laturnus, C., Ewers, C., Wieler, L. H. (2005). Identification of Genes Required for Avian Escherichia coli Septicemia by Signature-Tagged Mutagenesis. Infect. Immun. 73: 2818-2827 [Abstract] [Full Text]  
  • Ryu, J.-H., Beuchat, L. R. (2005). Biofilm Formation by Escherichia coli O157:H7 on Stainless Steel: Effect of Exopolysaccharide and Curli Production on Its Resistance to Chlorine. Appl. Environ. Microbiol. 71: 247-254 [Abstract] [Full Text]  
  • White, A. P., Gibson, D. L., Collinson, S. K., Banser, P. A., Kay, W. W. (2003). Extracellular Polysaccharides Associated with Thin Aggregative Fimbriae of Salmonella enterica Serovar Enteritidis. J. Bacteriol. 185: 5398-5407 [Abstract] [Full Text]  
  • Mizoguchi, K., Morita, M., Fischer, C. R., Yoichi, M., Tanji, Y., Unno, H. (2003). Coevolution of Bacteriophage PP01 and Escherichia coli O157:H7 in Continuous Culture. Appl. Environ. Microbiol. 69: 170-176 [Abstract] [Full Text]