1L1N

POLIOVIRUS 3C PROTEINASE

Summary for 1L1N

• Entry DOI: 10.2210/pdb1l1n/pdb
• Descriptor: Genome polyprotein: Picornain 3C (2 entities in total)
• Functional Keywords: beta barrel, trypsin-like, catalytic triad, viral protein, hydrolase
• Biological source: Human poliovirus 1
• Cellular location: Protein VP2: Virion. Protein VP3: Virion. Protein VP1: Virion. Protein 2B: Host cytoplasmic vesicle membrane; Peripheral membrane protein; Cytoplasmic side (Potential). Protein 2C: Host cytoplasmic vesicle membrane; Peripheral membrane protein; Cytoplasmic side (Potential). Protein 3A: Host cytoplasmic vesicle membrane; Peripheral membrane protein; Cytoplasmic side (Potential). Protein 3B: Virion (Potential). Picornain 3C: Host cytoplasm (Potential). RNA-directed RNA polymerase 3D-POL: Host cytoplasmic vesicle membrane; Peripheral membrane protein; Cytoplasmic side (Potential): P03300
• Total number of polymer chains: 2
• Total formula weight: 39294.63

Authors

Mosimann, S.C.,Chernaia, M.M.,Sia, S.,Plotch, S.,James, M.N.G. (deposition date: 2002-02-19, release date: 2002-04-10, Last modification date: 2024-02-14)

Primary citation

Mosimann, S.C.,Cherney, M.M.,Sia, S.,Plotch, S.,James, M.N.
Refined X-ray crystallographic structure of the poliovirus 3C gene product.
J.Mol.Biol., 273:1032-1047, 1997

PubMed Abstract: The X-ray crystallographic structure of the recombinant poliovirus 3C gene product (Mahoney strain) has been determined by single isomorphous replacement and non-crystallographic symmetry averaging and refined at 2.1 A resolution. Poliovirus 3C is comprised of two six-stranded antiparallel beta-barrel domains and is structurally similar to the chymotrypsin-like serine proteinases. The shallow active site cleft is located at the junction of the two beta-barrel domains and contains a His40, Glu71, Cys147 catalytic triad. The polypeptide loop preceding Cys147 is flexible and likely undergoes a conformational change upon substrate binding. The specificity pockets for poliovirus 3C are well-defined and modeling studies account for the known substrate specificity of this proteinase. Poliovirus 3C also participates in the formation of the viral replicative initiation complex where it specifically recognizes and binds the RNA stem-loop structure in the 5' non-translated region of its own genome. The RNA recognition site of 3C is located on the opposite side of the molecule in relation to its proteolytic active site and is centered about the conserved KFRDIR sequence of the domain linker. The recognition site is well-defined and also includes residues from the amino and carboxy-terminal helices. The two molecules in the asymmetric unit are related by an approximate 2-fold, non-crystallographic symmetry and form an intermolecular antiparallel beta-sheet at their interface.

PubMed: 9367789
DOI: 10.1006/jmbi.1997.1306

Experimental method

X-RAY DIFFRACTION (2.1 Å)