Structural biology of bacterial iron uptake.
To fulfill their nutritional requirement for iron, bacteria utilize various iron sources which include the host proteins transferrin and lactoferrin, heme, and low molecular weight iron chelators termed siderophores. The iron sources are transported into the Gram-negative bacterial cell via specific uptake pathways which include an outer membrane receptor, a periplasmic binding protein (PBP), and an inner membrane ATP-binding cassette (ABC) transporter. Over the past two decades, structures for the proteins involved in bacterial iron uptake have not only been solved, but their functions have begun to be understood at the molecular level. However, the elucidation of the three dimensional structures of all components of the iron uptake pathways is currently limited. Despite the low sequence homology between different bacterial species, the available three-dimensional structures of homologous proteins are strikingly similar. Examination of the current three-dimensional structures of the outer membrane receptors, PBPs, and ABC transporters provides an overview of the structural biology of iron uptake in bacteria.
Krewulak
Karla D
KD
Structural Biology Research Group, Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada T2N 1N4.
Vogel
Hans J
HJ
D018528:ATP-Binding Cassette Transporters / Q000737:chemistry / Q000378:metabolism / Q000502:physiology; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology; D006090:Gram-Negative Bacteria / Q000737:chemistry / Q000378:metabolism*; D006418:Heme / Q000737:chemistry / Q000502:physiology; D007501:Iron / Q000378:metabolism*; D007781:Lactoferrin / Q000737:chemistry / Q000378:metabolism / Q000502:physiology; D008565:Membrane Proteins / Q000737:chemistry / Q000502:physiology; D008954:Models, Biological; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D017386:Sequence Homology, Amino Acid; D017262:Siderophores / Q000737:chemistry / Q000378:metabolism / Q000502:physiology; D014168:Transferrin / Q000737:chemistry / Q000378:metabolism / Q000502:physiology
D018528:ATP-Binding Cassette Transporters; D001426:Bacterial Proteins; D008565:Membrane Proteins; D017262:Siderophores; D014168:Transferrin; C057616:tonB protein, Bacteria; D006418:Heme; D007501:Iron; D007781:Lactoferrin