Helicobacter pylori infection, susceptibility to

Helicobacter pylori is a microaerophilic, gram-negative bacterium that colonizes the gastric mucosa of approximately 50% of the world's population, and is a primary pathogenic factor in benign and malignant gastroduodenal disease (Warren and Marshall, 1983; Blaser and Parsonnet, 1994). Tomb et al. (1997) reported the complete sequence of the circular genome of H. pylori. The 1,667,867-bp genome contains 1,590 predicted coding sequences (genes). Sequence analysis of these genes indicated that the organism has systems for motility, for scavenging iron, and for DNA restriction and modification. Its survival in acid conditions depends, in part, on its ability to establish a positive inside-membrane potential in low pH. [from OMIM]