1INL

Crystal Structure of Spermidine Synthase from Thermotoga Maritima

Summary for 1INL

• Entry DOI: 10.2210/pdb1inl/pdb
• Descriptor: Spermidine synthase (2 entities in total)
• Functional Keywords: beta-barrel, rossmann fold, structural genomics, psi, protein structure initiative, midwest center for structural genomics, mcsg, transferase
• Biological source: Thermotoga maritima
• Cellular location: Cytoplasm : Q9WZC2
• Total number of polymer chains: 4
• Total formula weight: 136736.16

Authors

Korolev, S.,Skarina, T.,Ikeguchi, Y.,Pegg, A.E.,Joachimiak, A.,Edwards, A.,Savchenko, A.,Midwest Center for Structural Genomics (MCSG) (deposition date: 2001-05-14, release date: 2001-11-21, Last modification date: 2024-02-07)

Primary citation

Korolev, S.,Ikeguchi, Y.,Skarina, T.,Beasley, S.,Arrowsmith, C.,Edwards, A.,Joachimiak, A.,Pegg, A.E.,Savchenko, A.
The crystal structure of spermidine synthase with a multisubstrate adduct inhibitor.
Nat.Struct.Biol., 9:27-31, 2002

PubMed Abstract: Polyamines are essential in all branches of life. Spermidine synthase (putrescine aminopropyltransferase, PAPT) catalyzes the biosynthesis of spermidine, a ubiquitous polyamine. The crystal structure of the PAPT from Thermotoga maritima (TmPAPT) has been solved to 1.5 A resolution in the presence and absence of AdoDATO (S-adenosyl-1,8-diamino-3-thiooctane), a compound containing both substrate and product moieties. This, the first structure of an aminopropyltransferase, reveals deep cavities for binding substrate and cofactor, and a loop that envelops the active site. The AdoDATO binding site is lined with residues conserved in PAPT enzymes from bacteria to humans, suggesting a universal catalytic mechanism. Other conserved residues act sterically to provide a structural basis for polyamine specificity. The enzyme is tetrameric; each monomer consists of a C-terminal domain with a Rossmann-like fold and an N-terminal beta-stranded domain. The tetramer is assembled using a novel barrel-type oligomerization motif.

PubMed: 11731804
DOI: 10.1038/nsb737

Experimental method

X-RAY DIFFRACTION (1.5 Å)