Document Detail


Role of colanic acid exopolysaccharide in the survival of enterohaemorrhagic Escherichia coli O157:H7 in simulated gastrointestinal fluids.
MedLine Citation:
PMID:  16706906     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
AIM: This study evaluated the production of colanic acid (CA) exopolysaccharide (EPS) by Escherichia coli O157:H7 in relation to the pathogen's ability to survive under acidic conditions simulating the environment in the human gastrointestinal tract. METHODS AND RESULTS: Escherichia coli O157:H7 W6-13 and its CA-deficient mutant M4020 were examined for their resistance to bile salts, and their ability to survive in simulated gastric fluid containing pepsin (pH 2.0) and simulated intestinal fluid containing pancreatin (pH 8.0). The effect of acid adaptation at pH 5.5 on the survival of E. coli O157:H7 in simulated gastric fluid was also determined. The results indicated that the survivability of M4020, under conditions simulating the environment in the human gastrointestinal tract, reduced more drastically than the viability of W6-13. The presence of bile salts had a slight effect on both types of E. coli O157:H7 cells. The loss of CA did not change the ability of M4020 to respond to acid adaptation. CONCLUSION: The EPS CA may serve as a protective barrier to E. coli O157:H7 for its survival in the human gastrointestinal tract. SIGNIFICANCE AND IMPACT OF THE STUDY: The study contributes to a better understanding of the EPS affecting the ability of E. coli O157:H7 to combat acid stress.
Authors:
Y Mao; M P Doyle; J Chen
Related Documents :
17161946 - Synthesis and biological activation of an ethylene glycol-linked amino acid conjugate o...
21048866 - A simple enzymatic method for production of a wide variety of d-amino acids using l-ami...
19084616 - Simvastatin inhibits acidic extracellular ph-activated, outward rectifying chloride cur...
20141506 - Novel ph-sensitive hydrogels for colon-specific drug delivery.
19711446 - Study of physico-chemical properties of novel highly sulfated, aromatic, mimetics of he...
14499126 - Heterotrophic production of eicosapentaenoic acid by microalgae.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, Non-P.H.S.    
Journal Detail:
Title:  Letters in applied microbiology     Volume:  42     ISSN:  0266-8254     ISO Abbreviation:  Lett. Appl. Microbiol.     Publication Date:  2006 Jun 
Date Detail:
Created Date:  2006-05-18     Completed Date:  2006-07-19     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  8510094     Medline TA:  Lett Appl Microbiol     Country:  England    
Other Details:
Languages:  eng     Pagination:  642-7     Citation Subset:  IM    
Affiliation:
Center for Food Safety and Department of Food Science and Technology, The University of Georgia, Griffin, GA 30223-1797, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Escherichia coli O157 / drug effects,  growth & development*
Gastric Juice / microbiology*,  secretion
Heat-Shock Response
Humans
Hydrogen-Ion Concentration
Intestinal Secretions / microbiology*
Polysaccharides / metabolism*,  pharmacology
Polysaccharides, Bacterial / metabolism
Chemical
Reg. No./Substance:
0/Polysaccharides; 0/Polysaccharides, Bacterial; 9012-87-7/colanic acid

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Inhibition of bacterial quorum sensing by vanilla extract.
Next Document:  Drug resistance and random amplified polymorphic DNA analysis of Photobacterium damselae ssp. piscic...