Researchers are developing a completely new healing approach for Cholera
In a new study scientists were able to clarify how bacteria can survive the acidic environment of the stomach and invade the intestine. This research could lead to a new cholera treatment method.
Thousands of people die of cholera-causing respiratory failure in countries lacking clean drinking water every year. Its survival in the intestine and stomach is ensured by the pathogen Vibrio cholerae, by switching certain genetic factors off and on. Scientists at the University of Graz have discovered this and published it in the latest issue of the journal Proceedings of the National Academy of Sciences (PNAS).
Vibrio cholerae frolics in ponds and brackish water. If it affects a human, it must also be able to survive the passage through the acidic environment of the human stomach and then colonize the intestine. Graz researchers have found genes that play an important role in this. "In our laboratory, we studied the molecular basis of bacterial pathogens and their adaptation mechanisms to survive in the environment or in the host," explains co-author Stefan Schild from the Institute of Molecular Biosciences at the University of Graz. Of particular interest is the causative agent for the worldwide epidemic. Vibrio cholerae is transmitted through contaminated water. When someone becomes infected, the bacterium multiplies rapidly and produces the dangerous cholera toxin, which leads to severe diarrhea with life-threatening fluid loss.
The scientists have discovered which genes Vibrio cholerae turn on in the host. "Among other things, it could be investigated how in the intestine, the toxin is produced, which triggers the diarrhea," says Schild. Equally important may be which genes the pathogen turns off.
They have further developed a gene transcription monitoring system that captures differences in gene regulation with changing environmental and host conditions during the life cycle of Vibrio cholerae. "We actually found around 100 genes that are down-regulated after oral administration by the host," explained the Graz expert.
Cholera Treatment in Mouse Model
Using a "mouse model", bioscientists have identified in the laboratory a factor that is particularly suppressed. It is a chloride ion transporter. It is vital for the bacterium if it is still in the acid bath of the host's stomach: in this acidic environment, it helps the bacterium to detoxify chloride ions, thus protecting it from the acid. However, the chloride ion transporter continues its activity in the alkaline environment of the intestine, and it interferes with the energy balance of the bacterium. "It has been shown that the bacterium cannot invade the intestine if this factor is not turned off,” the expert emphasizes.
"If we could fake the bacterium in the gut that it's still in the stomach, the disease could not even break out," Schild concludes.
According to Schild, this could be a new approach to combating cholera.
Reference: Der Standard