D-Ribulose 1,5-Diphosphate Carboxylase from spinach 

One unit will convert 1.0 μmole of D-RuDP and CO₂ to 2.0 μmoles of D-3-phosphoglycerate per min at pH 7.8 at 25°C.

Exists as a 557 kDa hexadecamer composed of eight heavy chains each with a molecular weight of approximately 56 kDa and eight light chains of molecular weight 14 kDa. Each molecule contains one copper (II) ion.
pH optimum: ~7.9.
K_M for CO₂: ~0.45 mM.
Ribulose diphosphate becomes inhibitory at concentrations exceeding 0.7 mM. Orthophosphate and ammonium sulfate are competitive inhibitors. 3-Phosphoglycerate is a noncompetitive inhibitor.

partially purified powder

−20°C

Meth. Enzymol. 42, 472-480, (1975)

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