Refined crystal structure of ytterbium‐substituted carp parvalbumin 4.25 at 1.5 Å, and its comparison with the native and cadmium‐substituted structures

FEBS Letters

Lee, Lana¹  Edwards, Brian F.P.²  Kumar, Vinod D.³ 

[1] Department of Chemistry and Biochemistry, University of Windsor, Canada N9B 3P4;Department of Biochemistry, Wayne State University School of Medicine, Detroit, MI 48202, USA;Macromolecular Structure Laboratory, NCI-Frederick Cancer Research and Development Center, ABL-Basic Research Program, PO Box B, Frederick, MD 21702-1201, USA

关键词: Calcium binding protein;    Lanthanide;    Ytterbium-substituted;    X-ray structure;   

DOI  :  10.1016/0014-5793(91)80616-B

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The crystal structure of carp parvalbumin 4.25 containing a 1:1 molar ratio of ytterbium chloride to protein has been refined at 1.5 Å resolution by restrained least-squares methods to a crystallographic R value of 0.199. The crystal structure confirms the NMR studies, which suggest that low concentrations of ytterbium cause an extensive displacement of calcium from the EF metal binding site. A comparison of the ytterbium-substituted model with the native and cadmium-substituted structure show no significant differences, except around the substituted EF metal-binding region. The displacement of calcium by ytterbium at the EF site has caused a movement in the polypeptide backbone of Ser-91 and Asp-92. This movement resulted in an increase in the number of oxygen ligands bound to ytterbium in the EF site from seven to eight.

【 授权许可】

Unknown