Ribulose bisphosphate carboxylase (EC 126.96.36.199) (RuBisCO) [1,2] catalyzes the
initial step in Calvin's reductive pentose phosphate cycle in plants as well
as purple and green bacteria. It consists of a large catalytic unit and a
small subunit of undetermined function. In plants, the large subunit is coded
by the chloroplastic genome while the small subunit is encoded in the nuclear
genome. Molecular activation of RuBisCO by CO2 involves the formation of a
carbamate with the epsilon-amino group of a conserved lysine residue. This
carbamate is stabilized by a magnesium ion. One of the ligands of the
magnesium ion is an aspartic acid residue close to the active site lysine .
We developed a pattern which includes both the active site residue and the
metal ligand, and which is specific to RuBisCO large chains.
November 1995 / Pattern and text revised.
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