Acquisition of iron by Aeromonas salmonicida.
The ability of six typical and three atypical strains of Aeromonas salmonicida to sequester Fe3+ from the high-affinity iron chelators ethylenediaminedihydroxy-phenylacetic acid, lactoferrin, and transferrin was determined. Typical strains were readily able to sequester Fe3+ and used two different mechanisms. One mechanism was inducible and appeared to involve production of a low-molecular-weight soluble siderophore(s). Iron uptake by this mechanism was strongly inhibited by ferricyanide. One virulent strain displayed a second mechanism which was constitutive and required cell contact with Fe3+-lactoferrin or -transferrin. This strain did not produce a soluble siderophore(s) but could utilize the siderophore(s) produced by the other strain. Fe3+ uptake by this stripping mechanism was strongly inhibited by dinitrophenol. Atypical strains displayed a markedly reduced ability to sequester iron from high-affinity chelators, although one of them was able to utilize the siderophores produced by the typical strain. In all strains examined, Fe3+ limitation resulted in the increased synthesis of several high-molecular-weight outer membrane proteins.
D000333:Aeromonas / Q000254:growth & development / Q000378:metabolism*; D001692:Biological Transport; D002462:Cell Membrane / Q000378:metabolism; D003956:Dialysis; D007501:Iron / Q000378:metabolism*; D007700:Kinetics; D007781:Lactoferrin / Q000378:metabolism; D008565:Membrane Proteins / Q000302:isolation & purification; D008970:Molecular Weight; D013045:Species Specificity
D008565:Membrane Proteins; D007501:Iron; D007781:Lactoferrin