Five-stranded beta-sheet sandwiched with two alpha-helices: a structural link between restriction endonucleases EcoRI and EcoRV.

C Venclovas; A Timinskas; V Siksnys

doi:10.1002/prot.340200308

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Five-stranded beta-sheet sandwiched with two alpha-helices: a structural link between restriction endonucleases EcoRI and EcoRV.

C Venclovas·A Timinskas·V Siksnys

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Abstract

Examination of crystal structures of restriction endonucleases EcoRI and EcoRV complexes with their cognate DNA revealed a common structural element, which forms the core of both proteins. This element consists of a five-stranded beta-sheet and two alpha-helices packed against it and could be described as alpha-beta sandwich in which helices and beta-strands lie in two stacked layers. While the spatial structure of this alpha-beta sandwich is conserved in both enzymes, there are not detectable similarities between amino acid sequences except of a few residues involved in active site formation. Probably, other restriction endonucleases which have similar organization of the active site might possess similar structural element regardless of DNA sequence recognized and recognition elements in the enzyme used.

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Amino Acid Sequence Binding Sites Deoxyribonuclease EcoRI Deoxyribonucleases, Type II Site-Specific Escherichia coli Models, Molecular Molecular Sequence Data Mutagenesis, Site-Directed Protein Structure, Secondary Comparative Study Journal Article Research Support, Non-U.S. Gov't

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C Venclovas, A Timinskas, V Siksnys. 1994. Five-stranded beta-sheet sandwiched with two alpha-helices: a structural link between restriction endonucleases EcoRI and EcoRV.. https://doi.org/10.1002/prot.340200308

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