IRON ACQUISITION BY HELICOBACTER-PYLORI - IMPORTANCE OF HUMAN LACTOFERRIN

Helicobacter pylori is known to be an etiologic agent of gastritis and peptic ulcer disease in humans. However, the mechanism by which this organism acquires iron has not been studied. For this investigation, H . pylori was grown in iron-restricted medium. Siderophore production w as not detected by chemical assays, and the strains were unable to use enterochelin and pyochelin for growth in low-iron media. Human lactof errin supported full growth of the bacteria in media lacking other iro n sources, but neither human transferrin, bovine lactoferrin, nor hen ovotransferrin served as a source for iron. Since lactoferrin was foun d in significant amounts in human stomach resections with superficial or atrophic gastritis, the iron acquisition system of H. pylori by the human lactoferrin receptor system may play a major role in the virule nce of H. pylori infection.