Faster Process Developed to Test for Staph Infections

Color-enhanced staphylococcus bacteria (NIH)

3 February 2014. Researchers at University of Iowa in Iowa City designed a process with synthesized genetic material that detects dangerous staph infections in the body faster than with current methods. The team led by medical school professor James McNamara, with colleagues from the university and genetic systems company Integrated DNA Technologies in nearby Coralville, published its findings online yesterday in the journal Nature Medicine (paid subscription required).

Many infections caused by Staphylococcus aureus bacteria result in skin conditions, like impetigo, and can spread easily. Other forms of the infection can become more serious diseases, such as pneumonia and toxic shock syndrome, while others are resistant to antibiotics, including methicillin-resistant Staphylococcus aureus or MRSA. Staph infections can also be fatal for people with weakened immune systems.

One of the problems with controlling staph infections, particularly in health care settings, is the current method for diagnosing the condition, which requires taking a biopsy (tissue sample) and sending it to a lab for testing. The technique devised by McNamara and colleagues makes it possible to test for staph infections on the spot, and thus take action sooner to treat them.

The Iowa team’s solution uses synthesized RNA particles attracted to enzymes put out by staph bacteria, which makes it possible to target those bacteria. The RNA particles also have molecules at opposite ends that both fluoresce to emit light and extinguish the light emissions. When enzymes from staph bacteria encounter the RNA particles, the enzymes split the particles, separating the fluorescent molecules from the light blockers. As a result, the lighted ends of the particles can be detected, indicating a presence of staph bacteria.

In addition, this light-emitting property can last for an extended period of time, according to first author and post-doctoral research Frank Hernandez. “We designed a tracking system that specifically identifies bacterial body localization in less than one hour,” says Hernandez in a university statement. The researchers tested the concept in lab experiments, both in mice and with human blood serum.

McNamara, Hernandez, and other Iowa colleagues are listed as inventors on a patent application for the process filed in August 2012 by the university’s technology transfer office and Integrated DNA Technologies. The technology is available for licensing from the university.

Read more:

• Challenge Seeks Point-of-Care Staph Bacteria Detector
• Antibiotic Resistance Biosensor Developed for Staph Bacteria
• Selenium Found to Control Staph Bacteria on Implant Material
• FDA Approves Staph Bacteria Resistance Test

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