5YXC

Crystal structure of Zinc binding protein ZinT in complex with citrate from E. coli

Summary for 5YXC

• Entry DOI: 10.2210/pdb5yxc/pdb
• Descriptor: Metal-binding protein ZinT, ZINC ION, CITRIC ACID, ... (4 entities in total)
• Functional Keywords: zinc binding protein, complex, citrate, metal binding protein
• Biological source: Escherichia coli
• Total number of polymer chains: 2
• Total formula weight: 50106.80

Authors

Chen, J.,Wang, L.,Shang, F.,Xu, Y. (deposition date: 2017-12-04, release date: 2017-12-20, Last modification date: 2024-11-13)

Primary citation

Chen, J.,Wang, L.,Shang, F.,Dong, Y.,Ha, N.C.,Nam, K.H.,Quan, C.,Xu, Y.
Crystal structure of E. coli ZinT with one zinc-binding mode and complexed with citrate
Biochem. Biophys. Res. Commun., 500:139-144, 2018

PubMed Abstract: The ZnuABC ATP-binding cassette transporter found in gram-negative bacteria has been implicated in ensuring adequate zinc import into Zn(II)-poor environments. ZinT is an essential component of ZnuABC and contributes to metal transport by transferring metals to ZnuA, which delivers them to ZnuB in periplasmic zinc recruitment. Although several structures of E. coli ZinT have been reported, its zinc-binding sites and oligomeric state have not been clearly identified. Here, we report the crystal structure of E. coli ZinT at 1.76 Å resolution. This structure contains one zinc ion in its calycin-like domain, and this ion is coordinated by three highly conserved histidine residues (His167, His176 and His178). Moreover, three oxygen atoms (O, O and O) from the citrate molecule interact with zinc, giving the zinc ion stable octahedral coordination. Our EcZinT structure shows the fewest zinc ions bound of all reported EcZinT structures. Crystallographic packing and size exclusion chromatography suggest that EcZinT prefers to form monomers in solution. Our results provide insights into the molecular function of ZinT.

PubMed: 29596824
DOI: 10.1016/j.bbrc.2018.03.192

Experimental method

X-RAY DIFFRACTION (1.763 Å)