3OPF:
reference: The structure of TTHA0988 from Thermus thermophilus, a KipI-KipA homologue incorrectly annotated as an allophanate hydrolase., Jacques DA, Langley DB, Kuramitsu S, Yokoyama S, Trewhella J, Guss JM, Acta Crystallogr D Biol Crystallogr. 2011 Feb;67(Pt 2):105-11. Epub 2011, Jan 8. PMID: 21245531

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