Phosphatidylcholine enhances the activity of rat liver type II phosphatidylinositol‐kinase

FEBS Letters

Martínez-Arias, Wilma¹  Olsson, Henric¹  Jergil, Bengt¹ 

[1] Biochemistry, Chemical Centre, University of Lund, PO Box 124, S-221 00 Lund, Sweden

关键词: Phosphatidylinositol kinase;    Phosphatidylcholine dependence;    Rat liver;    PtdIns;    phosphatidylinositol;    PtdIns4P;    phosphatidylinositol 4-phosphate;    PtdIns(4;    5)P2;    phosphatidylinositol 4;    5-bisphosphate;    PtdCho;    Phosphatidylcholine;    PtdSer;    phosphatidylserine;    PtdGro;    phosphatidylglycerol;    PtdEtn;    phosphatidylethanol;    PtdOH;    phosphatidic acid;    CMC;    critical micelle concentration;    CDTA;    trans1;    2-diaminocyclohexane-N;    N;    N';    N'-tetraacetic acid;   

DOI  :  10.1016/0014-5793(93)81015-R

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

A PtdIns 4-kinase was purified extensively from rat liver exocytotic vesicles. The enzyme had a low K _m for ATP, was inhibited by adenosine, and had an apparent molecular mass of 54 kDa, indicating it to be a type II Ptdlns-kinase. The activity of the purified enzyme was enhanced several-fold by PtdCho, and to some extent by other phospholipids with basic polar head groups, and was inhibited by PtdSer. Kinetic analyses, presenting the substrate in mixed micelles of Triton X-100, Ptdlns and PtdCho, showed that the effect of PtdCho was both to increase V _max and to decrease the apparent K _m for micellar PtdIns.

【 授权许可】

Unknown