Cation‐ and peptide‐binding properties of human centrin 2

FEBS Letters

Durussel, Isabelle²  Cox, Jos A.²  Craescu, Constantin T.³  Middendorp, Sandrine¹  Blouquit, Yves³ 

[1] CNRS UMR 144 and Institut Curie, Paris, France;Department of Biochemistry, University of Geneva, Geneva, Switzerland;INSERM U350 and Institut Curie, Orsay, France

关键词: Centrosome;    Ca2+-binding protein;    EF-hand motif;    Conformational change;    Protein–peptide interaction;    CaM;    calmodulin;    ME;    melittin;    [Ca2+]0.5;    calcium concentration at half-maximal change;    K Ca;    stoichiometric Ca2+-binding constant;    TNS;    2-p-toluidinylnaphthalene-6-sulfonate;    ANS;    8-anilino-1-naphthalenesulfonate;   

DOI  :  10.1016/S0014-5793(00)01452-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Centrin and calmodulin (CaM) are closely related four-EF-hand Ca²⁺-binding proteins. While CaM is monomeric, centrin 2 is dimeric and binds only two Ca²⁺ per dimer, likely to site IV in each monomer. Ca²⁺ binding to centrin 2 displays pronounced negative cooperativity and a [Ca²⁺]_0.5 of 30 μM. As in CaM, Ca²⁺ binding leads to the exposure of a hydrophobic probe-accessible patch on the surface of centrin 2. Provided Ca²⁺ is present, centrin 2 forms a 1:1 peptide:monomer complex with melittin with an affinity of 100 nM. The complex binds four instead of two Ca²⁺. Our data point to surprising differences in the mode of activation of these homologous proteins.

【 授权许可】

Unknown