DOES CALMODULIN REGULATE THE AFFINITY OF THE HUMAN RED-CELL CA-2+ PUMP FOR ATP

被引：11

作者：

CARIDE, AJ

ROSSI, JPFC

GARRAHAN, PJ

REGA, AF

机构：

[1] Instituto de Química y Fisicoquímica Biológicas (UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires

来源：

BIOCHIMICA ET BIOPHYSICA ACTA | 1990年 / 1027卷 / 01期

关键词：

ATPase; Ca[!sup]2+[!/sup]-; Calcium pump; Calmodulin; Compound; 48/80;

D O I：

10.1016/0005-2736(90)90042-M

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：

(1) We have reexamined the effects of calmodulin and of the calmodulin antagonist, compound 48/80 on the interaction of ATP at its low-affinity site in the Ca2+-ATPase from human red cells. (2) At variance with our earlier proposal (Biochim. Biophys. Acta (1985) 816, 379-386) calmodulin increased the maximum effect of ATP without changing the apparent affinity for ATP at the low-affinity site. Accordingly, ATP increased the maximum activation by calmodulin without altering the apparent affinity of the Ca2+-ATPase for calmodulin. (3) Confirming our previous observation (Biochim. Biophys. Acta (1985) 816, 379-386) compound 48/80 lowered the apparent affinity of the Ca2+-ATPase for ATP at the low-affinity site. This has to be attributed to a direct effect of this compound on the enzyme rather than to its effect as calmodulin antagonist. © 1990.

引用

页码：21 / 24

页数：4

共 14 条

[11] COMPOUND 48 80 AND CALMODULIN MODIFY THE INTERACTION OF ATP WITH THE (CA2+ + MG2+)-ATPASE OF RED-CELL MEMBRANES [J].

ROSSI, JPFC ;

REGA, AF ;

GARRAHAN, PJ .

BIOCHIMICA ET BIOPHYSICA ACTA, 1985, 816 (02) :379-386

[12] STEADY-STATE KINETIC-ANALYSIS OF THE NA+/K+-ATPASE - THE EFFECTS OF ADENOSINE 5'-[BETA,GAMMA-METHYLENE]TRIPHOSPHATE ON SUBSTRATE KINETICS [J].

ROSSI, RC ;

GARRAHAN, PJ .

BIOCHIMICA ET BIOPHYSICA ACTA, 1989, 981 (01) :85-94

[13]

SEGEL IH, 1975, ENZYME KINETICS, P606

[14] SOME PROPERTIES OF THE PURIFIED (CA2++MG2+)-ATPASE FROM HUMAN RED-CELL MEMBRANES [J].

STIEGER, J ;

LUTERBACHER, S .

BIOCHIMICA ET BIOPHYSICA ACTA, 1981, 641 (01) :270-275

← 1 2 →