Kinetics of binding of Antp homeodomain to DNA analyzed by measurements of surface plasmon resonance

FEBS Letters

Seimiya, Makiko¹  Kurosawa, Yoshikazu¹ 

[1] Institute for Comprehensive Medical Science, Fujita Health University, Toyoake, Aichi 470-11, Japan

关键词: Homeodomain;    Surface plasmon resonance;    Entropy;    Enthalpy;    Non-electrostatic force;    ds;    double stranded;    K D;    dissociation constant;    BIA;    biospecific interaction analysis;    SPR;    surface plasmon resonance;    RU;    resonance unit(s);    k ass;    association rate constant;    k diss;    dissociation rate constant;    K A;    assocaation constant;   

DOI  :  10.1016/S0014-5793(96)01246-X

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The kinetics of binding of the Antp homeodomain to three kinds of DNA fragment were analyzed by measurements of surface plasmon resonance at various temperatures. Non-specific and specific binding of the homeodomain to DNA was examined. In the case of non-specific binding, the association rate constant (k _ass) was estimated to be 1.41–2.62 × 10⁵ M⁻¹ s⁻¹ and the dissociation rate constant (k _diss) was 1.36–3.10 × 10⁻² s⁻¹, thus, the dissociation constant (K _D) was 0.847–1.72 × 10⁻⁷ M. The association seemed to be driven by entropy. In the case of specific binding, by contrast, the enthalpy term seemed to contribute more to the binding than did the entropy term. The k _ass was 2.04–2.59 × 10⁵ M⁻¹ s⁻¹ and the k _diss was 0.759–1.16 × 10⁻³ s⁻¹, thus, the K _D was 2.93–5.69 × 10⁻⁹ M. These values were measured under the condition of 150 mM NaCl. Both interactions were strongly dependent on the concentration of NaCl. The K _D at 50 mM NaCl became several tens of times smaller than those at 150 mM. Possible reasons for the differences between non-specific and specific interactions are discussed.

【 授权许可】

Unknown