Nickel binding to the C-terminal tryptic fragment of a peptide from human kidney.
In kidney the nickel ion exists primarily as soluble cytoplasmic complexes. We have recently identified a major component of these complexes in the human kidney as a Ni(II) complex of a low molecular weight anionic peptide (Templeton, D.M. and Sarkar, B. (1985) Biochem. J. 230, 35-42). We have now purified a small amount of this peptide to homogeneity and developed an HPLC technique to study its metal-binding properties on sub-nanomole quantities. We are able to demonstrate a binding stoichiometry of one Ni atom per molecule of peptide, with an apparent dissociation constant of 1.1 X 10(-5) M. A similar site exists for Cd. The site for Ni persists after trypsinization, and is localized in the 20-residue C-terminal tryptic fragment of the peptide.
D000596:Amino Acids / Q000032:analysis; D001665:Binding Sites; D006801:Humans; D007668:Kidney / Q000378:metabolism*; D009532:Nickel / Q000378:metabolism*; D010446:Peptide Fragments / Q000378:metabolism*; D012995:Solubility; D014357:Trypsin
D000596:Amino Acids; D010446:Peptide Fragments; D009532:Nickel; D014357:Trypsin