The human stomach is a treacherous environment, bathed in a mixture of gastric acid and proteolytic enzymes. Most bacteria are incapable of surviving here, but Helicobacter pylori, a spiral-shaped bacterium that is infamous for causing ulcers, has managed to buck this trend, adapting to—even thriving in—this harshest of environments.
A neutralophile—an organism that lives optimally at a neutral pH—it synthesizes large quantities of urease, an enzyme that catalyzes the breakdown of urea to produce ammonia (NH3) and carbon dioxide (CO2), which raise the stomach’s extremely low pH to more comfortable levels. Another key to its success is its ability to make its way across the mucosa, a protective layer that separates the stomach’s highly acidic interior from the rest of the body. Without this layer, the gastric acid produced within would easily dissolve the stomach’s own walls.
Originally Syndicated via RSS from Ars Technica – News
