1V7L:
reference: Crystal Structure of the Pyrococcus horikoshii Isopropylmalate Isomerase Small Subunit Provides Insight into the Dual Substrate Specificity of the Enzyme., Yasutake Y, Yao M, Sakai N, Kirita T, Tanaka I, J Mol Biol 2004 Nov 19;344(2):325-33. PMID: 15522288

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