Identifying Diarrhea Causing Bacteria By Tiny Difference In Genes

The article publishes on Science Daily shows that researcher
from Helmholtz Centre for Infection, Germany find out a method to differentiate
between many kinds of bacteria that causes diarrhea. Researchers say that the
difference is found in the repetitive segments of DNA in every bacterium. A scientist
from HCI, Manfred Hofle, says, “With this method we are able to identify
bacterial strains as well as clarify their genetic relationships. Furthermore,
we can show how new pathogenic variants develop,” (Helmholtz Centre for
Infection Research).



A type of vibrio (spiral) shaped bacteria, a species of Cholera,
Vibrio cholerate strains is severely pathogenic and cause bad diarrhea. This bacterium
is found in drinking water and some food. Once it gets inside the human body,
it attacks the intestinal wall. Another type of vibrio bacteria that causes
diarrhea is Vibrio parahaemolyticus and only few bacteria in a human body are
enough to cause severe diarrhea. Thousands of Chile’s people are affected by this
bacterium in 1990. It is said that Vibrio parahaemolyticus bacteria has various
types which is difficult to differentiate. New technique developed By HCI
researchers is beneficial to find difference between these bacteria in a short
time. They researchers used “tandem repeats”, short and repetitive segments of
DNA, which are characteristics of each bacterium, with certain dyes. “Each dyes
DNA fragment recognizes a single tandem repeat, binding at it” (Helmholtz
Centre for Infection Research). They used six red dyed fragments to mark on six
tandem repeats which showed that each bacterium had different pattern and size
of tandem repeats to other bacteria.



This technique is very useful to identify different viruses
and bacteria that cause diseases in plants and animals. By using this
technique, scientist will be able to make antibiotics to kill different
bacteria which were thought similar before.