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Name: Borna
Status: Student
Age: 14
Location: N/A
Country: N/A
Date: N/A 


Question:
How can a bacteria survive in a stomach and keep eating it's tissue if the Ph of a stomach is 2?
If it is that way how come it can be treated with medications?



Replies:
There are only few bacteria specialized to survive in the stomach. For most others, the stomach is a real bottle neck, and most will die when they stay in it too long, or when the pH is too low (too acid). Don't forget, however, that food particles can temporary increase the pH, so that bacteria can 'sneek through' with a meal. That is how food-borne pathogens reach the intestines where they're fine.

The few bacteria that can survive in the stomach produce specific enzymes that increase the pH around them. Helicobacter pylori is the only example proven to date to live preferentially in the stomach. The enzyme they produce is Urease. They can survive long enough to reach the epithelial cells that line the stomach, and they live in the niches between these cells. The pH of such niches is pretty neutral. So although they can survive the acidity, they rather get away from it.

The medications you are prescribed to get rid of your Helicobacter (which can cause gastric ulcers) are antibiotics. They have specific antibacterial activity, and kill the bacteria without doing harm to the stomach tissue. These antibiotics are acid resistant.

Dr. Trudy Wassenaar
Curator of the Virtual Museum of Bacteria


Bacteria are the most diverse and adaptable of the living organisms. They have been found in the Dead Sea, polar ice and in the geysers at Yellowstone. The bacteria that live in the stomach are adapted to live there and probably couldn't live a higher pH. There are antibiotics that can treat them.

Van Hoeck



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