1YLH

Crystal Structure of Phosphoenolpyruvate Carboxykinase from Actinobaccilus succinogenes in Complex with Manganese and Pyruvate

Summary for 1YLH

• Entry DOI: 10.2210/pdb1ylh/pdb
• Related: 1YGG
• Descriptor: phosphoenolpyruvate carboxykinase, MANGANESE (II) ION, PHOSPHATE ION, ... (8 entities in total)
• Functional Keywords: phosphoenolpyruvate carboxykinase, disulphide bond, bound sulfhydrl reducing agent, lyase
• Biological source: Actinobacillus succinogenes
• Cellular location: Cytoplasm (By similarity): Q6W6X5
• Total number of polymer chains: 1
• Total formula weight: 62724.19

Authors

Leduc, Y.A.,Prasad, L.,Laivenieks, M.,Zeikus, J.G.,Delbaere, L.T. (deposition date: 2005-01-19, release date: 2005-06-28, Last modification date: 2023-11-15)

Primary citation

Leduc, Y.A.,Prasad, L.,Laivenieks, M.,Zeikus, J.G.,Delbaere, L.T.
Structure of PEP carboxykinase from the succinate-producing Actinobacillus succinogenes: a new conserved active-site motif.
Acta Crystallogr.,Sect.D, 61:903-912, 2005

PubMed Abstract: Actinobacillus succinogenes can produce, via fermentation, high concentrations of succinate, an important industrial commodity. A key enzyme in this pathway is phosphoenolpyruvate carboxykinase (PCK), which catalyzes the production of oxaloacetate from phosphoenolpyruvate and carbon dioxide, with the concomitant conversion of adenosine 5'-diphosphate to adenosine 5'-triphosphate. 1.85 and 1.70 A resolution structures of the native and a pyruvate/Mn(2+)/phosphate complex have been solved, respectively. The structure of the complex contains sulfhydryl reducing agents covalently bound to three cysteine residues via disulfide bonds. One of these cysteine residues (Cys285) is located in the active-site cleft and may be analogous to the putative reactive cysteine of PCK from Trypanosoma cruzi. Cys285 is also part of a previously unreported conserved motif comprising residues 280-287 and containing the pattern NXEXGXY(/F)A(/G); this new motif appears to have a structural role in stabilizing and positioning side chains that bind substrates and metal ions. The first few residues of this motif connect the two domains of the enzyme and a fulcrum point appears to be located near Asn280. In addition, an active-site Asp residue forms two coordinate bonds with the Mn(2+) ion present in the structure of the complex in a symmetrical bidentate manner, unlike in other PCK structures that contain a manganese ion.

PubMed: 15983413
DOI: 10.1107/S0907444905008723

Experimental method

X-RAY DIFFRACTION (1.7 Å)