Table 2.
Prominent iron transport systems and associated regulatory factors in pathogenic Yersinia.
| System | Functional propertya |
|---|---|
| TonB-ExbB-ExbD | Energizer complex |
| Fur & RyhB | Iron homeostasis in response to iron |
| ArcA-ArcB & Fnr | Iron homeostasis in response to oxygen |
| FERRIC TRANSPORTERS | |
| Ybt | Yersiniabactin siderophore system |
| Ynp | Pseudochelin siderophore system |
| Ysu | Yersiniachelin siderophore system |
| Iuc | Aerobactin siderophore system |
| FERROUS TRANSPORTERS | |
| Yfe | ABC importer of iron and manganese |
| Feo | Non-ABC-importer |
| HEME TRANSPORTERS | |
| Hmu | ABC importer |
| Has | Hemophore system |
a
Whether these systems are contained in all three human pathogenic Yersinia has been addressed in part by the study by Forman et al. (2010). This study revealed significant variation in coding potential among the three species and even among strains of a species. Hence, mechanisms of iron transport can have redundant functions or operate only in a specific niche.