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1ef0
From Proteopedia
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CRYSTAL STRUCTURE OF PI-SCEI MINIPRECURSOR
Overview
PI-SceI is a member of a class of proteins (inteins) that excise, themselves from a precursor protein and in the process ligate the flanking, protein sequences (exteins). We report here the 2.1-A resolution crystal, structure of a PI-SceI miniprecursor (VMA29) containing 10 N-terminal, extein residues and 4 C-terminal extein residues. Mutations at the N- and, C-terminal splicing junctions, blocking in vivo protein splicing, allowed, the miniprecursor to be purified and crystallized. The structure reveals, both the N- and C-terminal scissile peptide bonds to be in distorted trans, conformations (tau approximately 100 degrees ). Modeling of the wild-type, PI-SceI based on the VMA29 structure indicates a large conformational, change (movement of >9 A) must occur to allow transesterification to be, completed. A zinc atom was discovered at the C-terminal splicing junction., Residues Cys(455), His(453), and Glu(80) along with a water molecule, (Wat(53)) chelate the zinc atom. The crystal structure of VMA29 has, captured the intein in its pre-spliced state.
About this Structure
1EF0 is a Single protein structure of sequence from Saccharomyces cerevisiae with ZN as ligand. Active as H(+)-transporting two-sector ATPase, with EC number 3.6.3.14 Full crystallographic information is available from OCA.
Reference
Structural insights into the protein splicing mechanism of PI-SceI., Poland BW, Xu MQ, Quiocho FA, J Biol Chem. 2000 Jun 2;275(22):16408-13. PMID:10828056
Page seeded by OCA on Tue Nov 20 13:57:08 2007
