Activity of phosphatidylinositol-specific phospholipase C from Bacillus cereus with thiophosphate analogs of dimyristoylphosphatidylinositol

被引：7

作者：

Hendrickson, HS ^{[1
]}

Giles, AN ^{[1
]}

Vos, SE ^{[1
]}

机构：

[1] ST OLAF COLL, DEPT CHEM, NORTHFIELD, MN 55057 USA

来源：

CHEMISTRY AND PHYSICS OF LIPIDS | 1997年 / 89卷 / 01期

基金：

美国国家科学基金会;

关键词：

Bacillus cereus; 1,2-Dimyristoyloxypropane-3-thiophospho(1D-1-myo-inositol); phosphatidylinositol-specific phospholipase C; thiophosphate; interfacial kinetics;

D O I：

10.1016/S0009-3084(97)00059-5

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Phosphatidylinositol-specific phospholipase C (PI-PLC) was studied with sonicated dispersions of a thiophosphate analog of phosphatidylinositol, 1,2-dimyristoyloxypropane-3-thiophospho(1D-1-myo-inositol) (D-thio-DMPI). Kinetic parameters were derived from the rate as a function of bulk lipid concentration at constant saturating surface concentration of substrate (case I), and as a function of surface concentration of substrate at a constant saturating bulk concentration of lipid (case II). The substrate, D-thio-DMPI, was diluted with L-thio-DMPI or dimyristoyl phosphatidylmethanol (DMPM). In the presence of L-thio-DMPI, values for V-max = 133 mu mol min(-1) mg(-1), K-s' (the apparent dissociation constant for the enzyme-interface complex)= 0.097 mM, and K-m* (the apparent interfacial Michaelis constant) = 0.22 mol fraction were obtained. DMPM caused enzyme inhibition in case I but no inhibition in case II. L-Thio-DMPI is an ideal neutral diluent with which to study the kinetics of PI-PLC. (C) 1997 Elsevier Science Ireland Ltd.

引用

页码：45 / 53

页数：9

共 29 条

[1] EFFECT OF MONOLAYER SURFACE PRESSURE ON THE ACTIVITIES OF PHOSPHOINOSITIDE-SPECIFIC PHOSPHOLIPASE-C-BETA-1, PHOSPHOLIPASE-C-GAMMA-1, AND PHOSPHOLIPASE-C-DELTA-1 [J].