压力对脂质双分子层中重组碱性磷酸酶催化作用的影响。

Pressure effects on catalysis by alkaline phosphatase reconstituted in lipid bilayers.

作者信息

Kitano H, Katsukawa M

出版信息

Biochem Int. 1985 Dec;11(6):921-7.

Abstract

Bovine intestinal alkaline phosphatase (EC 3.1.3.1) was reconstituted into lipid bilayers by a dilution method using n-octylglucopyranoside. From the kinetic measurements at various pressures, the volume of activation (delta V not equal to) and volume change in substrate binding (delta V) were estimated for free and reconstituted ALP. The delta V not equal to and delta V values for free ALP and reconstituted ALP in the gel state liposome showed opposite tendencies (-23 ml . mol-1 [delta V not equal to], 35 ml . mol-1 [delta V] for free ALP and 27 ml . mol-1 [delta V not equal to], -36 ml . mol-1 [delta V] for reconstituted ALP, respectively), which suggest both strong desolvation effect of enzyme molecule by the surrounding lipids and drastic conformational change of the enzyme molecule by the reconstitution into liposomes.

摘要

通过使用正辛基吡喃葡萄糖苷的稀释法，将牛小肠碱性磷酸酶（EC 3.1.3.1）重组到脂质双层中。根据在不同压力下的动力学测量，估算了游离和重组碱性磷酸酶的活化体积（ΔV≠）和底物结合时的体积变化（ΔV）。游离碱性磷酸酶和处于凝胶态脂质体中的重组碱性磷酸酶的ΔV≠和ΔV值呈现相反的趋势（游离碱性磷酸酶分别为-23 ml·mol-1[ΔV≠]，35 ml·mol-1[ΔV]；重组碱性磷酸酶分别为27 ml·mol-1[ΔV≠]，-36 ml·mol-1[ΔV]），这表明周围脂质对酶分子有强烈的去溶剂化作用，并且酶分子重组到脂质体中会发生剧烈的构象变化。