3HJ6

Structure of Halothermothrix orenii fructokinase (FRK)

Summary for 3HJ6

• Entry DOI: 10.2210/pdb3hj6/pdb
• Descriptor: Fructokinase (2 entities in total)
• Functional Keywords: fructokinase, fructose, kinase, transferase, carbohydrate metabolism
• Biological source: Halothermothrix orenii
• Total number of polymer chains: 2
• Total formula weight: 72517.65

Authors

Chua, T.K.,Seetharaman, J.,Kasprzak, J.M.,Ng, C.,Patel, B.K.,Love, C.,Bujnicki, J.M.,Sivaraman, J. (deposition date: 2009-05-21, release date: 2010-06-09, Last modification date: 2024-10-30)

Primary citation

Chua, T.K.,Seetharaman, J.,Kasprzak, J.M.,Ng, C.,Patel, B.K.,Love, C.,Bujnicki, J.M.,Sivaraman, J.
Crystal structure of a fructokinase homolog from Halothermothrix orenii
J.Struct.Biol., 171:397-401, 2010

PubMed Abstract: Fructokinase (FRK; EC 2.7.1.4) catalyzes the phosphorylation of d-fructose to d-fructose 6-phosphate (F6P). This irreversible and near rate-limiting step is a central and regulatory process in plants and bacteria, which channels fructose into a metabolically active state for glycolysis. Towards understanding the mechanism of FRK, here we report the crystal structure of a FRK homolog from a thermohalophilic bacterium Halothermothrixorenii (Hore_18220 in sequence databases). The structure of the Hore_18220 protein reveals a catalytic domain with a Rossmann-like fold and a beta-sheet "lid" for dimerization. Based on comparison of Hore_18220 to structures of related proteins, we propose its mechanism of action, in which the lid serves to regulate access to the substrate binding sites. Close relationship of Hore_18220 and plant FRK enzymes allows us to propose a model for the structure and function of FRKs.

PubMed: 20493950
DOI: 10.1016/j.jsb.2010.05.007

Experimental method

X-RAY DIFFRACTION (2.8 Å)