1VZ4:
reference: Succinate complex crystal structures of the alpha-ketoglutarate-dependent dioxygenase AtsK: steric aspects of enzyme self-hydroxylation., Muller I, Stuckl C, Wakeley J, Kertesz M, Uson I, J Biol Chem. 2005 Feb 18;280(7):5716-23. Epub 2004 Nov 12. PMID: 15542595

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