Structural Studies of a Stabilized Phosphoenzyme Intermediate of Ca -ATPase*
نویسندگان
چکیده
From the ‡Skirball Institute of Biomolecular Medicine and Department of Cell Biology, New York University School of Medicine, New York, New York 10012, the §New York Structural Biology Center, New York, New York 10027, U410 INSERM, Faculté de Medicine Xavier Bichat, 16 rue Henri Huchard, B.P. 416, 75870 Paris cedex 18, France, **URA CNRS 2096 and SBPM/DBCM, CEA Saclay, 91191 Gif-sur-Yvette cedex, France, and the ‡‡Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Observatory, Cape Town 7925, South Africa
منابع مشابه
Structural studies of a stabilized phosphoenzyme intermediate of Ca2+-ATPase.
Ca(2+)-ATPase belongs to the family of P-type ATPases and maintains low concentrations of intracellular Ca(2+). Its reaction cycle consists of four main intermediates that alternate ion binding in the transmembrane domain with phosphorylation of an aspartate residue in a cytoplasmic domain. Previous work characterized an ultrastable phosphoenzyme produced first by labeling with fluorescein isot...
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Acylphosphatase, purified from human erythrocytes, actively hydrolyzes the acylphosphorylated intermediate of human red blood cell membrane Ca(2+)-ATPase. This effect occurred with acylphosphatase amounts (up to 10 units/mg membrane protein) that fall within the physiological range. Furthermore, a very low Km value, 3.41 +/- 1.16 (S.E.) nM, suggests a high affinity in acylphosphatase for the ph...
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