6S2V:
reference: A nucleotide-switch mechanism mediates opposing catalytic activities of Rel enzymes., Tamman H, Van Nerom K, Takada H, Vandenberk N, Scholl D, Polikanov Y, Hofkens J, Talavera A, Hauryliuk V, Hendrix J, Garcia-Pino A, Nat Chem Biol. 2020 Aug;16(8):834-840. doi: 10.1038/s41589-020-0520-2. Epub 2020 , May 11. PMID: 32393900

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