322
G. Garg et al.
Table 14.2 List protein Channel of Fe transportation in microbes
Model system
Location
Receptor proteins
References
Bacteria
An outer membrane
receptor
Fec A and Fep A
Sajeed Ali and
Vidhale (2013)
An inner membrane
receptor
Fec CDE- Fep CDE
(an ATP dependent
transporter systems/or
ABC-Transporter systems)
and
Ton B
Sajeed Ali and
Vidhale (2013)
Cytosol
Ent ABCD protein
Sajeed Ali and
Vidhale (2013)
Fungi
Siderophore mediated Fe transport system
Mechanisms
Process
References
The shuttle mechanism • Fe-siderophore complex is
transported across the cell
membrane and released
the Fe +3 ions from the
ligands and reduced by the
reductive enzymes
• Recycle the free
siderophore
• e.g., transporting
ferrichrome in Ustilago
maydis
Ardon et al. (1998)
The taxicab
mechanism
• Fe +3 extracellular
siderophore is transferred
across the cell membrane
to intracellular membrane
ligands
e.g., Rhodotorula species
Winkelmann and
Huschka (1987)
The hydrolytic
mechanism
• After the transportation of
Fe +3 siderophore complex
inside the cell, it undergoes
reductive and degenerative
steps and release the Fe +3
• Fe +3 is then reduced into
Fe +2 and the siderophore
is further released out
e.g., uptake of Fe +3
tri-acetyl-fusarinine
complexes by Mycelia
sterilia
Adjimani and
Emery (1988)
(continued)