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1unk
From Proteopedia
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| , resolution 1.8Å | |||||||
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STRUCTURE OF COLICIN E7 IMMUNITY PROTEIN
Overview
Site-specific cleavage of mRNA has been identified in vivo for the polycistronic colicin E7 operon (ColE7), which occurs between G and A nucleotides located at the Asp52 codon (GAT) of the immunity gene (ceiE7). In vitro, this specific cleavage occurs only in the presence of the ceiE7 gene product (ImmE7). The crystal structure of dimeric ImmE7 has been determined at 1.8 A resolution by X-ray crystallographic analysis. We found that several residues located at the interface of dimeric ImmE7 bear surprising resemblance to the active sites of some RNases. These results suggest that dimeric ImmE7 may possess a novel RNase activity that cleaves its own mRNA at a specific site and thus autoregulates translational expression of the downstream celE7 gene as well as degradation of the upstream ceaE7 mRNA.
About this Structure
1UNK is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
A novel role of ImmE7 in the autoregulatory expression of the ColE7 operon and identification of possible RNase active sites in the crystal structure of dimeric ImmE7., Hsieh SY, Ko TP, Tseng MY, Ku W, Chak KF, Yuan HS, EMBO J. 1997 Mar 17;16(6):1444-54. PMID:9135159
Page seeded by OCA on Thu Mar 20 14:34:21 2008
