1apa
From Proteopedia
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X-RAY STRUCTURE OF A POKEWEED ANTIVIRAL PROTEIN, CODED BY A NEW GENOMIC CLONE, AT 0.23 NM RESOLUTION. A MODEL STRUCTURE PROVIDES A SUITABLE ELECTROSTATIC FIELD FOR SUBSTRATE BINDING.
Overview
We have determined the crystal structure of alpha-pokeweed antiviral, protein, a member of ribosome-inactivating proteins, at 0.23 nm, resolution, by the molecular-replacement method. The crystals belong to, the space group P2(1)2(1)2 with unit-cell dimensions a = 4.71, b = 11.63, and c = 4.96 nm, and contain one protein molecule/asymmetric unit based on, a crystal volume/unit protein molecular mass of 2.1 x 10(-3) nm3/Da. The, crystallographic residual value was reduced to 17.2% (0.6-0.23 nm, resolution) with root-mean-square deviations in bond lengths of 1.9 pm and, bond angles of 2.2 degrees. The C alpha-C alpha distance map shows that, alpha-pokeweed antiviral protein is composed of three modules, the, N-terminal (Ala1-Leu76), the central (Tyr77-Lys185) and the C-terminal, (Tyr186-Thr266) modules. The substrate-binding site is formed as a cleft, between the central and C-terminal modules and all the active residues, exist on the central module. The electrostatic potential around the, substrate-binding site shows that the central and C-terminal module sides, of this cleft have a negatively and a positively charged region, respectively. This charge distribution in the protein seems to provide a, suitable interaction with the substrate rRNA.
About this Structure
1APA is a Single protein structure of sequence from Phytolacca americana. Full crystallographic information is available from OCA.
Reference
X-ray structure of a pokeweed antiviral protein, coded by a new genomic clone, at 0.23 nm resolution. A model structure provides a suitable electrostatic field for substrate binding., Ago H, Kataoka J, Tsuge H, Habuka N, Inagaki E, Noma M, Miyano M, Eur J Biochem. 1994 Oct 1;225(1):369-74. PMID:7925458
Page seeded by OCA on Tue Nov 20 11:01:13 2007
