1geh
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| , resolution 2.8Å | |||||||
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| Ligands: | |||||||
| Activity: | Ribulose-bisphosphate carboxylase, with EC number 4.1.1.39 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CRYSTAL STRUCTURE OF ARCHAEAL RUBISCO (RIBULOSE 1,5-BISPHOSPHATE CARBOXYLASE/OXYGENASE)
OverviewOverview
BACKGROUND: Ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) is the key enzyme of the Calvin-Benson cycle and catalyzes the primary reaction of CO2 fixation in plants, algae, and bacteria. Rubiscos have been so far classified into two types. Type I is composed of eight large subunits (L subunits) and eight small subunits (S subunits) with tetragonal symmetry (L8S8), but type II is usually composed only of two L subunits (L2). Recently, some genuinely active Rubiscos of unknown physiological function have been reported from archaea. RESULTS: The crystal structure of Rubisco from the hyperthermophilic archaeon Thermococcus kodakaraensis KOD1 (Tk-Rubisco) was determined at 2.8 A resolution. The enzyme is composed only of L subunits and showed a novel (L2)5 decameric structure. Compared to previously known type I enzymes, each L2 dimer is inclined approximately 16 degrees to form a toroid-shaped decamer with its unique L2-L2 interfaces. Differential scanning calorimetry (DSC), circular dichroism (CD), and gel permeation chromatography (GPC) showed that Tk-Rubisco maintains its secondary structure and decameric assembly even at high temperatures. CONCLUSIONS: The present study provides the first structure of an archaeal Rubisco, an unprecedented (L2)5 decamer. Biochemical studies indicate that Tk-Rubisco maintains its decameric structure at high temperatures. The structure is distinct from type I and type II Rubiscos and strongly supports that Tk-Rubisco should be classified as a novel type III Rubisco.
About this StructureAbout this Structure
1GEH is a Single protein structure of sequence from Thermococcus kodakarensis. Full crystallographic information is available from OCA.
ReferenceReference
Crystal structure of a novel-type archaeal rubisco with pentagonal symmetry., Kitano K, Maeda N, Fukui T, Atomi H, Imanaka T, Miki K, Structure. 2001 Jun;9(6):473-81. PMID:11435112
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