title: Expression of a high-affinity mechanism for acquisition of transferrin iron by Neisseria meningitidis.
abstract: Iron-starved meningococci grown at either pH 7.2 or 6.6 were capable of removing and incorporating iron from human transferrin by a saturable, cell surface mechanism that specifically recognized transferrin rather than iron. The maximum expression of the iron uptake system occurred after 4 h of iron starvation. The uptake of the iron was dependent upon a functioning electron transport chain and was sensitive to 60 degrees C and trypsin. Cells grown under iron-sufficient conditions were incapable of accumulating iron from transferrin. No evidence was found for a primary role for cell-free soluble siderophores in the removal of iron from transferrin. The nonpathogenic neisseriae, Neisseria flava and N. sicca, were unable to utilize iron on transferrin.
mesh_terms: D001692:Biological Transport; D004579:Electron Transport; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000378:metabolism*; D007502:Iron Chelating Agents / Q000502:physiology; D007700:Kinetics; D009345:Neisseria meningitidis / Q000378:metabolism*; D017262:Siderophores; D014168:Transferrin / Q000378:metabolism*; D014357:Trypsin / Q000494:pharmacology
chemical_list: D007502:Iron Chelating Agents; D017262:Siderophores; D014168:Transferrin; D007501:Iron; D014357:Trypsin