A long-sought test for direct detection of disease-causing E. coli bacteria

February 18, 2008
E. coli
Researchers have developed a test for direct detection of disease-causing E. coli bacteria. This photo shows an electron micrograph of a bacteria cluster. Credit: Courtesy of USDA-Agricultural Research Service

Biochemists in Japan are reporting development of a long-sought direct test for identifying the presence E. coli bacteria that get into water and food as a result of fecal contamination. That contamination causes millions of cases of food poisoning and other gastrointestinal illness around the world each year. Their study is scheduled for the April 4 issue of ACS’ Biotechnology Progress.

In the report, Yasunori Tanji and colleagues point out that tests now in use do not directly identify E. coli. Instead, these tests detect “coliform” bacteria that health officials use as indicators for fecal contamination. Coliforms, however, can originate from natural sources, and are not always reliable indicators of fecal contamination. Direct tests for E. coli do exist, but are too time-consuming and complex for general use.

The new study describes successful use of genetically engineered viruses that infect E. coli to identify a wide range of E. coli strains found in sewage. Researchers first engineered the viruses to be harmless to E. coli. Then they gave the viruses genes to produce green fluorescent proteins. The resulting viruses reveal the presence of E. coli by lighting up and glowing after infecting the bacteria. The test uses a fluorescent microscope to detect the glow and the presence of disease-causing bacteria, and takes only a few hours.

Source: ACS

Explore further: Tracing the evolution of a drug-resistant pathogen

Related Stories

Horizontal gene transfer in E. coli

May 19, 2015

Escherichia coli O104 is an emergent disease-causing bacterium various strains of which are becoming increasingly well known and troublesome. The pathogen causes bloody diarrhea as well as and potentially fatal kidney damage, ...

Researchers connect climate change to food safety

March 6, 2015

Climate change can affect our food safety in a number of ways. In a European study, researchers at Wageningen University and Ghent University (Belgium) state that there is often a relationship between long-term changes in ...

Recommended for you

Short wavelength plasmons observed in nanotubes

July 28, 2015

The term "plasmons" might sound like something from the soon-to-be-released new Star Wars movie, but the effects of plasmons have been known about for centuries. Plasmons are collective oscillations of conduction electrons ...

New chemistry makes strong bonds weak

July 28, 2015

Researchers at Princeton have developed a new chemical reaction that breaks the strongest bond in a molecule instead of the weakest, completely reversing the norm for reactions in which bonds are evenly split to form reactive ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.