Prokaryotic calcium‐binding protein of the calmodulin superfamily Calcium binding to a Saccharopolyspora erythraea 20 kDa protein

FEBS Letters

Andersson, Ingrid²  Drakenberg, Torbjörn²  Bylsma, Niels²  Leadlay, Peter F.¹  Forsén, Sture² 

[1] Cambridge Centre for Molecular Recognition, Department of Biochemistry University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK;Physical Chemistry 2, Chemical Center, University of Lund, POB 124, S-221 00 Lund, Sweden

关键词: Calcium binding protein;    Prokaryotic;    Saccharopolyspora erythraea;    NMR;    Calcium affinity;    DTT;    1;    4-dithiothreitol;    EDTA;    ethylenediamine-tetraacetic acid;    Tris;    tris(hydroxymethyl)aminomethane;    Quin2;    2-[[2-[bis(carboxymethyl)amino]-5-methylphenoxy]methyl]-6-mothoxy-8-[bis-(carboxymethyl)amino]quinoline;    SDS;    sodium dodecyl sulfate;    IEF;    isoelectric focusing;    DFP;    diisopropyl-fluorophosphate;   

DOI  :  10.1016/0014-5793(92)80096-Y

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The EF-hand calcium-binding protein from Saccharopolyspora erythraea has been shown, using ¹¹³Cd NMR, to possess three Cd²⁺-ion binding sites. This indicates that of the four EF-hand motifs in the molecule, one (probably site 2) is unable to bind Cd²⁺-ions. Data from the titration of the protein with Ca²⁺, in the presence of Quin2, were fitted to a curve calculated on the assumption that the protein contains three high affinity Ca²⁺ binding sites, two of which (pK ₁ = 8.0. pK ₂ = 9.0) are strongly cooperative, and one single site (pK ₃ = 7.5). Preliminary ¹H NMR experiments indicate marked structural changes upon Ca²⁺-binding.

【 授权许可】

Unknown