Presence of a high-affinity Ca2+- and Mg2+-dependent ATPase in rat peritoneal mast-cell membranes.
نویسندگان
چکیده
Purified perigranular and plasma membranes isolated from rat peritoneal mast cells were examined for Ca2+- and Mg2+-dependent ATPase activity. Isolated perigranular membranes contained only a low-affinity Ca2+- or Mg2+-dependent ATPase (Km greater than 0.5 mM). The plasma membranes contained both a low-affinity Ca2+- or Mg2+-dependent ATPase (Km = 0.4 mM, Vmax. = 20 nmol of Pi/min per mg), as well as a high-affinity Ca2+- and Mg2+-dependent ATPase (Km = 0.2 microM, Vmax. = 6 nmol of Pi/min per mg).
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ورودعنوان ژورنال:
- The Biochemical journal
دوره 226 1 شماره
صفحات -
تاریخ انتشار 1985