1U80

Phosphopantothenoylcysteine synthetase from E. coli, CMP complex

Summary for 1U80

• Entry DOI: 10.2210/pdb1u80/pdb
• Related: 1U7U 1U7W 1U7Z
• Descriptor: Coenzyme A biosynthesis bifunctional protein coaBC, PHOSPHATE ION, CYTIDINE-5'-MONOPHOSPHATE, ... (4 entities in total)
• Functional Keywords: coenzyme a biosynthesis, ligase
• Biological source: Escherichia coli
• Total number of polymer chains: 3
• Total formula weight: 75754.55

Authors

Stanitzek, S.,Augustin, M.A.,Huber, R.,Kupke, T.,Steinbacher, S. (deposition date: 2004-08-04, release date: 2004-11-30, Last modification date: 2023-11-29)

Primary citation

Stanitzek, S.,Augustin, M.A.,Huber, R.,Kupke, T.,Steinbacher, S.
Structural Basis of CTP-Dependent Peptide Bond Formation in Coenzyme A Biosynthesis Catalyzed by Escherichia coli PPC Synthetase
STRUCTURE, 12:1977-1988, 2004

PubMed Abstract: Phosphopantothenoylcysteine (PPC) synthetase forms a peptide bond between 4'-phosphopantothenate and cysteine in coenzyme A biosynthesis. PPC synthetases fall into two classes: eukaryotic, ATP-dependent and eubacterial, CTP-dependent enzymes. We describe the first crystal structure of E. coli PPC synthetase as a prototype of bacterial, CTP-dependent PPC synthetases. Structures of the apo-form and the synthetase complexed with CTP, the activated acyl-intermediate, 4'-phosphopantothenoyl-CMP, and with the reaction product CMP provide snapshots along the reaction pathway and detailed insight into substrate binding and the reaction mechanism of peptide bond formation. Binding of the phosphopantothenate moiety of the acyl-intermediate in a cleft at the C-terminal end of the central beta sheet of the dinucleotide binding fold is accomplished by an otherwise flexible flap. A second disordered loop may control access of cysteine to the active site. The conservation of functionalities involved in substrate binding and catalysis provides insight into similarities and differences of prokaryotic and eukaryotic PPC synthetases.

PubMed: 15530362
DOI: 10.1016/j.str.2004.08.007

Experimental method

X-RAY DIFFRACTION (2.85 Å)