2OG0:
reference: Fis targets assembly of the xis nucleoprotein filament to promote excisive recombination by phage lambda., Papagiannis CV, Sam MD, Abbani MA, Yoo D, Cascio D, Clubb RT, Johnson RC, J Mol Biol. 2007 Mar 23;367(2):328-43. Epub 2007 Jan 3. PMID: 17275024

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