1DUT

FIV DUTP PYROPHOSPHATASE

Summary for 1DUT

• Entry DOI: 10.2210/pdb1dut/pdb
• Descriptor: DUTP PYROPHOSPHATASE, MAGNESIUM ION (3 entities in total)
• Functional Keywords: polyprotein, hydrolase, aspartyl protease, endonuclease, rna-directed dna polymerase, nucleotide metabolism, acid anhydride hydrolase
• Biological source: Feline immunodeficiency virus
• Total number of polymer chains: 2
• Total formula weight: 28788.21

Authors

Prasad, G.S.,Stura, E.A.,Mcree, D.E.,Laco, G.S.,Hasselkus-Light, C.,Elder, J.H.,Stout, C.D. (deposition date: 1996-09-15, release date: 1997-01-27, Last modification date: 2024-02-07)

Primary citation

Prasad, G.S.,Stura, E.A.,McRee, D.E.,Laco, G.S.,Hasselkus-Light, C.,Elder, J.H.,Stout, C.D.
Crystal structure of dUTP pyrophosphatase from feline immunodeficiency virus.
Protein Sci., 5:2429-2437, 1996

PubMed Abstract: We have determined the crystal structure of dUTP pyrophosphatase (dUTPase) from feline immunodeficiency virus (FIV) at 1.9 A resolution. The structure has been solved by the multiple isomorphous replacement (MIR) method using a P6(3) crystal form. The results show that the enzyme is a trimer of 14.3 kDa subunits with marked structural similarity to E. coli dUTPase. In both enzymes the C-terminal strand of an anti-parallel beta-barrel participates in the beta-sheet of an adjacent subunit to form an interdigitated, biologically functional trimer. In the P6(3) crystal form one trimer packs on the 6(3) screw-axis and another on the threefold axis so that there are two independent monomers per asymmetric unit. A Mg2+ ion is coordinated by three asparate residues on the threefold axis of each trimer. Alignment of 17 viral, prokaryotic, and eukaryotic dUTPase sequences reveals five conserved motifs. Four of these map onto the interface between pairs of subunits, defining a putative active site region; the fifth resides in the C-terminal 16 residues, which is disordered in the crystals. Conserved motifs from all three subunits are required to create a given active site. With respect to viral protein expression, it is particularly interesting that the gene for dUTPase (DU) resides in the middle of the Pol gene, the enzyme cassette of the retroviral genome. Other enzymes encoded in the Pol polyprotein, including protease (PR), reverse transcriptase (RT), and most likely integrase (IN), are dimeric enzymes, which implies that the stoichiometry of expression of active trimeric dUTPase is distinct from the other Pol-encoded enzymes. Additionally, due to structural constraints, it is unlikely that dUTPase can attain an active form prior to cleavage from the polyprotein.

PubMed: 8976551

Experimental method

X-RAY DIFFRACTION (1.9 Å)