OVERPRODUCTION OF CAMPYLOBACTER FERRITIN IN ESCHERICHIA-COLI AND INDUCTION OF PARACRYSTALLINE INCLUSION BY FERROUS COMPOUND

The ferritin gene (cft) of Campylobacter jejuni was overexpressed in c ells of Escherichia coli using a T7 RNA polymerase expression system. Many round particles which were the same size as the ferritin particle s purified from C. jejuni were observed in the lysate of the cft-overe xpressed E. coli cells, Since most of them were devoid of a central el ectron dense core consisting of ferric irons, the Campylobacter ferrit ins overproduced in E. coli seemed to be apoferritin, When large amoun ts of ferrous iron (supplied as FeSO4) were added to culture medium, t he cft-overexpressed cells formed large inclusion bodies of paracrysta lline arrays comprised of ferritin particles with central electron den se cores, The addition of ferric irons did not produce paracrystalline inclusion.