Purification of the synaptosomal plasma membrane (Ca(2+) + Mg(2+))-ATPase from pig brain.
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ABSTRACT:
SUBMITTER: Salvador JM
PROVIDER: S-EPMC1217169 | biostudies-other | 1996 Apr
REPOSITORIES: biostudies-other
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Project description:A Ca2+-ATPase (Ca2+- and Mg2+-requiring ATPase) was purified from a synaptic plasma-membrane fraction of rat brain. This enzyme had properties similar to those of plasma-membrane Ca2+-ATPases from other organs: its splitting of ATP was dependent on both Ca2+ and Mg2+, it bound in a Ca2+-dependent fashion to calmodulin-Sepharose and it cross-reacted with specific antibodies raised against human erythrocyte-membrane Ca2+-ATPase. It had an apparent Mr of 138 000, similar to those of plasma-membrane ATPases from human erythrocyte and from dog heart sarcolemma. Previous high-Ca2+-affinity ATPases observed in brain had Mr 100 000; in at least one case, such an ATPase probably represented a different type of enzyme, derived from coated vesicles.
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