Is the cytoplasmic loop of MerT, the mercuric ion transport protein, involved in mercury transfer to the mercuric reductase?
In MerT, the mercury transporter, a first cysteine pair, located in the first trans-membrane helix, receives mercury from the periplasm. Then, a second cysteine pair, housed in a cytoplasmic loop connecting the second and the third trans-membrane helices, is thought to transfer the metal to another cysteine pair located in the N-terminal extension of the mercuric reductase. We found that a 23-amino acid synthetic peptide corresponding to the cytoplasmic loop can bind one mercury atom per molecule and that this mercury atom can be transferred specifically to MerAa. The solution structure of Hg-bound ppMerT has been solved by 1H NMR spectroscopy.
Rossy
Emmanuel
E
Laboratoire de Chimie et Biochimie des Centres Redox Biologiques, DRDC/CB, CEA-Grenoble, France.
Sénèque
Olivier
O
Lascoux
David
D
Lemaire
David
D
Crouzy
Serge
S
Delangle
Pascale
P
Covès
Jacques
J
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D001692:Biological Transport / Q000502:physiology; D027682:Cation Transport Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D013058:Mass Spectrometry; D008628:Mercury / Q000737:chemistry / Q000378:metabolism*; D015394:Molecular Structure; D010088:Oxidoreductases / Q000378:metabolism*; D010455:Peptides / Q000235:genetics / Q000378:metabolism; D017510:Protein Folding; D017434:Protein Structure, Tertiary
D001426:Bacterial Proteins; D027682:Cation Transport Proteins; D010455:Peptides; C094115:mercury transport protein, bacterial; D010088:Oxidoreductases; C021551:mercuric reductase; D008628:Mercury