UZH researches faster bacteria detection

(CONNECT) Researchers at the University of Zurich (UZH) are working on faster detection of clinical bacteria. At the heart of the investigations is the bacterium Escheria coli (E.coli), according to a statement from the Swiss National Science Foundation (SNSF), which supported the UZH research group. Also involved in the research is the rqmicro AG from Schlieren, a spin-off of the Swiss Federal Institute of Technology in Zurich (ETH) founded in 2013.

E. coli is a common and diverse type of bacteria that occurs naturally in the intestines of humans and animals, but also in the environment. The bacteria are one of the main causes of bloodstream and urinary tract infections as well as serious intestinal diseases. Observations in Switzerland show that resistance in bacteria developed strongly between 2004 and 2024. In order to be able to fight them safely in the event of an infection, a rapid diagnosis is required. However, current methods only allow E. coli to be detected after eleven hours.

"We want to detect certain bacteria earlier, even if they are only present in small quantities, by staining them. We also want to capture them directly in the blood so that we can analyze a larger number more quickly," Markus Seeger, Head of Research at the Institute of Medical Microbiology at UZH, is quoted as saying in the press release. In order to mark the E. coli, the envelope of the bacterium must be penetrated. This is largely covered by lipopolysaccharides (LPS) with a large number of antigens. The variability of these antigens makes it difficult to use antibodies.

The researchers are therefore concentrating on outer membrane proteins (OMP), in particular OmpA, which is present in 95 percent of all E. coli. So-called nanobodies can be produced here. These nanobodies can be provided with fly codes, genetically encoded peptide barcodes that are optimised for detection by mass spectrometry. With a detector from rqmicro, E. coli can be identified more quickly. The researchers hope that diagnostics could be shortened to two hours and targeted antibiotic treatment could be started.

The study was recently published in Nature Communications Biology. ce/ww