Modification of ATP regulatory function in sacroplasmic reticulum Ca2+-ATPase by hydrophobic molecules
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چکیده
منابع مشابه
Energy interconversion by the sarcoplasmic reticulum Ca2+-ATPase: ATP hydrolysis, Ca2+ transport, ATP synthesis and heat production.
The sarcoplasmic reticulum of skeletal muscle retains a membrane bound Ca2+-ATPase which is able to interconvert different forms of energy. A part of the chemical energy released during ATP hydrolysis is converted into heat and in the bibliography it is assumed that the amount of heat produced during the hydrolysis of an ATP molecule is always the same, as if the energy released during ATP clea...
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The K’ activation profile of the (Cap+ + My’+)-dependent ATPase of sarcoplasmic reticulum vesicles is markedly changed by the free magnesium concentration. At 0.2 mM Mg’+, a complex dependence on the K+ concentration is observed which changes to a simple hyperbolic dependence when Mg’+ is raised to 3 mM. The degree of activation by K+ is always higher at 0.2 rnH than at 3 mM MgY+. At 0.2 mM Mg”...
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Phosphorylation of sarcoplasmic reticulum ATPase with Pi and phosphoryl transfer from the phosphoenzyme to ADP to form ATP were studied in experiments including two sequential steps in the absence of a transmembrane Ca2+ gradient. This was accomplished with a variety of experimental manipulations including jumps of Ca2+ concentrations, pH, temperature, and water activity. Phosphorylation with ...
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Sarcolipin (SLN) is a small peptide found in the sarcoplasmic reticulum of skeletal muscle. It is predicted to contain a single hydrophobic transmembrane alpha-helix. Fluorescence emission spectra for the single Trp residue of SLN suggest that SLN incorporates fully into bilayers of dioleoylphosphatidylcholine, but only partially into bilayers of phosphatidylcholines with long (C(22) or C(24)) ...
متن کاملCa2’-ATPase Membrane Crystals in Sarcoplasmic Reticulum
Vanadate induces the formation of two-dimensional crystalline arrays of Ca2+-ATPase molecules in sarcoplasmic reticulum. The Ca2+-ATPase membrane crystals are evenly distributed among the terminal cisternae and longitudinal tubules of sarcoplasmic reticulum, but very few crystals were observed in the T tubules. Tryptic cleavage of the Ca2+ transport ATPase into two major fragments (A and B) did...
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ژورنال
عنوان ژورنال: European Journal of Biochemistry
سال: 1990
ISSN: 0014-2956,1432-1033
DOI: 10.1111/j.1432-1033.1990.tb19411.x