Disease-causing Escherichia coli: 'I will survive'

Sep 09, 2009

Strains of Escherichia coli bacteria that cause food poisoning have been shown to have marked differences in the numbers of genes they carry compared to laboratory strains of E. coli. Some of these genes may enable them to survive stresses such as those caused by modern food processing techniques or exploit food sources that laboratory E. coli strains cannot use.

Dr Karin Heurlier and colleagues at the Universities of Nottingham and Birmingham in conjunction with Biolog Inc of California USA, used powerful high throughput analytical tools (phenotype microarrays) that enabled them to compare about 2000 growth characteristics of several pathogenic (disease-causing) E. coli with a non-pathogenic laboratory E. coli strain. At the Society for General Microbiology's meeting at Heriot-Watt University, Edinburgh, today (9 September) they reported that they had found that the pathogenic strains could survive in different conditions compared to the standard laboratory, non-pathogenic strain.

Contamination by foodborne E. coli occurs in processed foods such as ready prepared salads, fermented sausages (e.g. salami), dairy products and fruit juices as well as more usually in raw and partly cooked meat products, indicating that the bacteria are able to survive modern food processing techniques. The researchers found differences between strains in how they responded to antimicrobial compounds, and in their reactions to oxygen availability, acidity and chemical stresses. They could also use different constituents in foods for their nutrition compared to standard laboratory E. coli strains.

"The laboratory E. coli strain K-12 is one of the best understood organisms on Earth," said Dr Heurlier, "But because it has become so used to being grown in laboratory conditions, it may not react to stresses in the same way as pathogenic strains - such as E. coli O157:H7 can. Our research shows that there are definite growth and nutrition differences between E. coli strains and therefore results obtained with laboratory strains may not be typical of what happens in the 'real' world".

Source: Society for General Microbiology

Explore further: Fighting bacteria—with viruses

add to favorites email to friend print save as pdf

Related Stories

Resistant gut bacteria will not go away by themselves

Jun 19, 2007

E. coli bacteria that have developed resistance to antibiotics will probably still be around even if we stop using antibiotics, as these strains have the same good chance as other bacteria of continuing to colonise the gut, ...

Ridding meat of E. coli

Jul 03, 2008

You may be able to enjoy a rare hamburger soon, thanks to a discovery made by a team of University of Alberta researchers.

Magnetic nanoparticles detect and remove harmful bacteria

Nov 19, 2007

Researchers in Ohio report the development of magnetic nanoparticles that show promise for quickly detecting and eliminating E. coli, anthrax, and other harmful bacteria. In laboratory studies, the nanoparticles helped detect ...

Recommended for you

Fighting bacteria—with viruses

Jul 24, 2014

Research published today in PLOS Pathogens reveals how viruses called bacteriophages destroy the bacterium Clostridium difficile (C. diff), which is becoming a serious problem in hospitals and healthcare institutes, due to its re ...

Atomic structure of key muscle component revealed

Jul 24, 2014

Actin is the most abundant protein in the body, and when you look more closely at its fundamental role in life, it's easy to see why. It is the basis of most movement in the body, and all cells and components ...

Brand new technology detects probiotic organisms in food

Jul 23, 2014

In the food industr, ity is very important to ensure the quality and safety of products consumed by the population to improve their properties and reduce foodborne illness. Therefore, a team of Mexican researchers ...

Protein evolution follows a modular principle

Jul 23, 2014

Proteins impart shape and stability to cells, drive metabolic processes and transmit signals. To perform these manifold tasks, they fold into complex three-dimensional shapes. Scientists at the Max Planck ...

Report on viruses looks beyond disease

Jul 22, 2014

In contrast to their negative reputation as disease causing agents, some viruses can perform crucial biological and evolutionary functions that help to shape the world we live in today, according to a new report by the American ...

User comments : 0