4H0W

Bismuth bound human serum transferrin

Summary for 4H0W

• Entry DOI: 10.2210/pdb4h0w/pdb
• Related: 3QYT
• Descriptor: Serotransferrin, FE (III) ION, CARBONATE ION, ... (7 entities in total)
• Functional Keywords: bismuth, iron transporter, metal transport
• Biological source: Homo sapiens (human)
• Total number of polymer chains: 1
• Total formula weight: 76095.69

Authors

Yang, N.,Zhang, H.,Wang, M.,Hao, Q.,Sun, H. (deposition date: 2012-09-10, release date: 2012-12-26, Last modification date: 2024-10-30)

Primary citation

Yang, N.,Zhang, H.,Wang, M.,Hao, Q.,Sun, H.
Iron and bismuth bound human serum transferrin reveals a partially-opened conformation in the N-lobe.
Sci Rep, 2:999-999, 2012

PubMed Abstract: Human serum transferrin (hTF) binds Fe(III) tightly but reversibly, and delivers it to cells via a receptor-mediated endocytosis process. The metal-binding and release result in significant conformational changes of the protein. Here, we report the crystal structures of diferric-hTF (Fe(N)Fe(C)-hTF) and bismuth-bound hTF (Bi(N)Fe(C)-hTF) at 2.8 and 2.4 Å resolutions respectively. Notably, the N-lobes of both structures exhibit unique "partially-opened" conformations between those of the apo-hTF and holo-hTF. Fe(III) and Bi(III) in the N-lobe coordinate to, besides anions, only two (Tyr95 and Tyr188) and one (Tyr188) tyrosine residues, respectively, in contrast to four residues in the holo-hTF. The C-lobe of both structures are fully closed with iron coordinating to four residues and a carbonate. The structures of hTF observed here represent key conformers captured in the dynamic nature of the transferrin family proteins and provide a structural basis for understanding the mechanism of metal uptake and release in transferrin families.

PubMed: 23256035
DOI: 10.1038/srep00999

Experimental method

X-RAY DIFFRACTION (2.4 Å)