6UJ6

X-ray Crystal Structure of Chromium-transferrin with Synergistic Anion Malonate

Summary for 6UJ6

• Entry DOI: 10.2210/pdb6uj6/pdb
• Descriptor: Transferrin, CHROMIUM ION, MALONATE ION, ... (6 entities in total)
• Functional Keywords: chromium, transferrin, human, metal transport
• Biological source: Homo sapiens (Human)
• Total number of polymer chains: 1
• Total formula weight: 77463.05

Authors

Petersen, C.M.,Edwards, K.C.,Gilbert, N.C.,Vincent, J.B.,Thompson, M.K. (deposition date: 2019-10-02, release date: 2020-09-30, Last modification date: 2024-10-30)

Primary citation

Petersen, C.M.,Edwards, K.C.,Gilbert, N.C.,Vincent, J.B.,Thompson, M.K.
X-ray structure of chromium(III)-containing transferrin: First structure of a physiological Cr(III)-binding protein.
J.Inorg.Biochem., 210:111101-111101, 2020

PubMed Abstract: Transferrin, the Fe(III) transport protein in mammalian blood, has been suggested to also serve as a Cr(III) transporter and as part of a Cr(III) detoxification system; however, the structure of the metal-binding sites has never been fully elucidated with bound Cr(III). Chromium(III)-transferrin was crystallized in the presence of the synergistic anion malonate. In the crystals, the protein exists with a closed C-terminal lobe containing a Cr(III) ion and an open, unoccupied N-terminal lobe. The overall structure and the metal ion environments are extremely similar to those of Fe(III)- and Ti(IV)-containing transferrin crystallized under comparable conditions. The octahedral coordination about the Cr(III) is comprised of four ligands provided by the protein (two tyrosine residues, a histidine residue, and an aspartate residue) and a chelating malonate anion. This represents the first crystal structure of a Cr(III)-containing protein that binds Cr(III) as part of its physiological function.

PubMed: 32650146
DOI: 10.1016/j.jinorgbio.2020.111101

Experimental method

X-RAY DIFFRACTION (2.68 Å)