Siderophore production and iron-regulated envelope proteins of Helicobacter pylori.

All Helicobacter pylori strains tested produced extracellular siderophores, detected by a modified Universal Detection medium, but growth on this medium was poor. By using the iron chelating compound, 2,2'-dipyridyl, outer membrane proteins of 78 and 40 kDa were detected in some, but not all strains examined. No direct binding of lactoferrin or transferrin (the mechanism used by Neisseria to obtain iron) could be demonstrated for H. pylori. Some other techniques for the study of iron-limitation on bacteria were found to be unsuitable for H. pylori.