Titration calorimetry of anesthetic-protein interaction: Negative enthalpy of binding and anesthetic potency

Issaku Ueda, Michio Yamanaka

研究成果: Contribution to journalArticle

32 引用 (Scopus)

抜粋

Anesthetic potency increases at lower temperatures. In contrast, the transfer enthalpy of volatile anesthetics from water to macromolecules is usually positive. The transfer decreases at lower temperature. It was proposed that a few selective proteins bind volatile anesthetics with negative ΔH, and these proteins are involved in signal transduction. There has been no report on direct estimation of binding ΔH of anesthetics to proteins. This study used isothermal titration calorimetry to analyze chloroform binding to bovine serum albumin. The calorimetrically measured ΔH(cal) was -10.37 kJ · mol-1. Thus the negative ΔH of anesthetic binding is not limited to signal transduction proteins. The binding was saturable following Fermi-Dirac statistics and is characterized by the Langmuir adsorption isotherms, which is interfacial. The high-affinity association constant, K1 was 2150 ± 132 M-1 (K(D) = 0.47 mM) with the maximum binding number, B(max) = 3.7 ± 0.2. The low-affinity K was 189 ± 3.8 M-1 (K(D) = 5.29 mM), with a B(max) of 13.2 ± 0.3. Anesthetic potency is a function of the activity of anesthetic molecules, not the concentration. Because the sign of ΔH determines the temperature dependence of distribution of anesthetic molecules, it is irrelevant to the temperature dependence of anesthetic potency.

元の言語英語
ページ(範囲)1812-1817
ページ数6
ジャーナルBiophysical Journal
72
発行部数4
DOI
出版物ステータス出版済み - 4 1997

All Science Journal Classification (ASJC) codes

  • Biophysics

フィンガープリント Titration calorimetry of anesthetic-protein interaction: Negative enthalpy of binding and anesthetic potency' の研究トピックを掘り下げます。これらはともに一意のフィンガープリントを構成します。

  • これを引用