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Genome-wide Purification of Extrachromosomal Circular DNA from Eukaryotic Cells
Published on: April 4, 2016
Activity of coliphage HK022 excisionase (Xis) in the absence of DNA binding
Pnina Gottfried1, Nava Silberstein, Ezra Yagil
1Department of Biochemistry, Tel-Aviv University, Tel-Aviv 69978, Israel.
Abstract:
A mutated excisionase (Xis) protein of coliphage HK022 whose single Cys residue was replaced by Ser does not bind to its two tandem binding sites (X1, X2) on the P arm of attR. Despite its DNA-binding inability the protein showed 30% excision activity of the wild type Xis both in vitro and in vivo. This partial activity is attributed to the interaction of Xis with integrase that is retained in the mutant protein. This protein-protein interaction occurs in the absence of DNA binding.
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