A NEISSERIA-MENINGITIDIS FBPABC MUTANT IS INCAPABLE OF USING NONHEME IRON FOR GROWTH

The neisserial fbpABC locus has been proposed to act as an iron-specif ic ABC transporter system. To confirm this assigned function, we const ructed an fbpABC mutant in Neisseria meningitidis by insertional inact ivation of fbpABC with a selectable antibiotic marker. The mutant was unable to use iron supplied from human transferrin, human lactoferrin, or iron chelates. However, the use of iron from heme and human hemogl obin was unimpaired. These results support the obligatory participatio n of fbpABC in neisserial periplasmic iron transport and do not indica te a role for this genetic locus in the heme iron pathway.