3NQW:
reference: A metazoan ortholog of SpoT hydrolyzes ppGpp and functions in starvation responses., Sun D, Lee G, Lee JH, Kim HY, Rhee HW, Park SY, Kim KJ, Kim Y, Kim BY, Hong JI, Park C, Choy HE, Kim JH, Jeon YH, Chung J, Nat Struct Mol Biol. 2010 Oct;17(10):1188-94. Epub 2010 Sep 5. PMID: 20818390

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