Key points from article :
Modified bacteria function as data loggers for information on gene activity and have been tested in mice.
Bacteria incorporate snippets of their own messenger RNA (mRNA) into the CRISPR array.
CRISPR array of the bacterial species Fusicatenibacter saccharivorans introduced into a strain of the intestinal bacterium Escherichia coli.
It is regarded as safe in humans and available as a probiotic.
Reverse transcriptase and CRISPR-associated proteins are necessary for incorporating the DNA snippet into the CRISPR array.
Faecal samples from the animals were analysed using high-throughput DNA sequencing for reconstructing the genetic information of the mRNA snippets.
“This new method lets us obtain information directly from the gut, without having to disturb intestinal functions,” says Andrew Macpherson, Professor and Director of Gastroenterology at University Hospital Bern.
Major advantages over endoscopies, which is unpleasant for patients and always involves disturbing intestinal function, due to bowel emptying.
“Bacteria are very good at registering environmental conditions and adapting their metabolism to new circumstances such as dietary changes.”
Researchers hope to use the method to determine the dietary status of children or adults, to diagnose malnutrition or decide whether a patient needs nutritional supplements.
Specific mRNA profiles of gut bacteria that switch to inflammation mode were identified.
Sensor bacteria can be modified so that they need certain nutrients and therefore can survive only inside the gut of a patient.
Research conducted by ETH Zurich, University Hospital of Bern and the University of Bern, led by Randall Platt, published in Science.
