1GN8

PHOSPHOPANTETHEINE ADENYLYLTRANSFERASE IN COMPLEX WITH Mn2+ATP FROM ESCHERICHIA COLI

Summary for 1GN8

• Entry DOI: 10.2210/pdb1gn8/pdb
• Related: 1B6T 1QJC
• Descriptor: PHOSPHOPANTETHEINE ADENYLYLTRANSFERASE, SULFATE ION, ADENOSINE-5'-TRIPHOSPHATE, ... (5 entities in total)
• Functional Keywords: transferase, coenzyme a biosynthesis, nucleotidyltransferase
• Biological source: ESCHERICHIA COLI
• Total number of polymer chains: 2
• Total formula weight: 37131.68

Authors

Izard, T. (deposition date: 2001-10-03, release date: 2002-01-17, Last modification date: 2023-12-13)

Primary citation

Izard, T.
The Crystal Structures of Phosphopantetheine Adenylyltransferase with Bound Substrates Reveal the Enzyme'S Catalytic Mechanism
J.Mol.Biol., 315:487-, 2001

PubMed Abstract: Phosphopantetheine adenylyltransferase (PPAT) is an essential enzyme in the coenzyme A pathway that catalyzes the reversible transfer of an adenylyl group from ATP to 4'-phosphopantetheine (Ppant) in the presence of magnesium. To investigate the reaction mechanism, the high-resolution crystal structures of the Escherichia coli PPAT have been determined in the presence of either ATP or Ppant. Structural details of the catalytic center revealed specific roles for individual amino acid residues involved in substrate binding and catalysis. The side-chain of His18 stabilizes the expected pentacovalent intermediate, whereas the side-chains of Thr10 and Lys42 orient the nucleophile for an in-line displacement mechanism. The binding site for the manganese ion that interacts with the phosphate groups of the nucleotide has also been identified. Within the PPAT hexamer, one trimer is in its substrate-free state, whereas the other is in a substrate-bound state.

PubMed: 11812124
DOI: 10.1006/JMBI.2001.5272

Experimental method

X-RAY DIFFRACTION (1.83 Å)