抽象的

Autoimmune illness and chronic gastritis caused by helicobacter enteric bacteria.

Aimi Jhon

In the human stomach, Helicobacter pylori have developed a particularly peculiar ecological niche. In vitro H. pylori can survive at a pH of 4, and urease activity is necessary for the bacterium to infiltrate animals. In a pH range between 4 and 7, urease does not, however, significantly contribute to the organism's ability to survive. Preliminary research suggests that new proteins are produced when H. pylori cells are brought down from pH 7 to pH 3, and the gene encoding a P-type adenosine triphosphatase that may catalyse NH4+/H+ exchange across the cytoplasmic membrane has been cloned. Other mechanisms of pH homeostasis are still poorly understood.