A NEW METHOD FOR MONITORING THE KINETICS OF CALCIUM-BINDING TO THE SARCOPLASMIC-RETICULUM CA-2+-ATPASE EMPLOYING THE FLASH-PHOTOLYSIS OF CAGED-CALCIUM

被引：4

作者：

DELONG, LJ

PHILLIPS, CM

KAPLAN, JH

SCARPA, A

BLASIE, JK

机构：

[1] UNIV PENN, REG LASER & BIOTECHNOL LABS, PHILADELPHIA, PA 19104 USA

[2] UNIV PENN, SCH MED, DEPT PHYSIOL, PHILADELPHIA, PA 19104 USA

[3] CASE WESTERN RESERVE UNIV, DEPT PHYSIOL & BIOPHYS, CLEVELAND, OH 44106 USA

来源：

JOURNAL OF BIOCHEMICAL AND BIOPHYSICAL METHODS | 1990年 / 21卷 / 04期

关键词：

DM-nitrophen; Flash-photolysis; Sarcoplasmic reticulum;

D O I：

10.1016/0165-022X(90)90007-Y

中图分类号：

Q5 [生物化学];

学科分类号：

071010 ; 081704 ;

摘要：

The kinetics of Ca2+ binding to the high-affinity sites of the sarcoplasmic reticulum (SR) Ca2+-ATPase were directly investigated by continuously monitoring the extravesicular calcium concentration via the metallochromic indicator Arsenazo III following the release of Ca2+ from a photolabile caged-calcium molecule, 1-(2-nitro-4,5-dimethoxyphenyl)-N,N,N′,N′-tetrakis [(oxycarbonyl)methyl]-1,2-ethanediamine DM-nitrophen), utilizing a pulsed Nd:YAG laser for photolysis. The nature of the binding kinetics is at least biphasic over the first 400 ms for vesicular dispersions of SR. The stoichiometry for calcium binding expressed as Ca:E1 ′ P has been calculated to be ′ 1.4:1 for the pure SR preparation under the reaction conditions employed. © 1990.

引用

页码：333 / 339

页数：7