Crystal structure of a divalent metal ion transporter CorA at 2.9 angstrom resolution.
CorA family members are ubiquitously distributed transporters of divalent metal cations and are considered to be the primary Mg2+ transporter of Bacteria and Archaea. We have determined a 2.9 angstrom resolution structure of CorA from Thermotoga maritima that reveals a pentameric cone-shaped protein. Two potential regulatory metal binding sites are found in the N-terminal domain that bind both Mg2+ and Co2+. The structure of CorA supports an efflux system involving dehydration and rehydration of divalent metal ions potentially mediated by a ring of conserved aspartate residues at the cytoplasmic entrance and a carbonyl funnel at the periplasmic side of the pore.
Eshaghi
Said
S
Division of Biophysics, Department of Medical Biochemistry and Biophysics, Karolinska Institute, SE-171 77 Stockholm, Sweden. Said.Eshaghi@ki.se
Niegowski
Damian
D
Kohl
Andreas
A
Martinez Molina
Daniel
D
Lesley
Scott A
SA
Nordlund
Pär
P
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D001665:Binding Sites; D027682:Cation Transport Proteins / Q000737:chemistry* / Q000378:metabolism; D002712:Chlorides / Q000032:analysis / Q000378:metabolism; D003035:Cobalt / Q000737:chemistry / Q000378:metabolism*; D018360:Crystallography, X-Ray; D057927:Hydrophobic and Hydrophilic Interactions; D008274:Magnesium / Q000737:chemistry / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D017510:Protein Folding; D020836:Protein Structure, Quaternary; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D020124:Thermotoga maritima / Q000737:chemistry*; D014867:Water / Q000737:chemistry
D001426:Bacterial Proteins; D027682:Cation Transport Proteins; D002712:Chlorides; D014867:Water; D003035:Cobalt; D008274:Magnesium