2FM7:
reference: Evolution of enzymatic activity in the tautomerase superfamily: mechanistic and structural consequences of the L8R mutation in 4-oxalocrotonate tautomerase., Poelarends GJ, Almrud JJ, Serrano H, Darty JE, Johnson WH Jr, Hackert ML, Whitman CP, Biochemistry. 2006 Jun 27;45(25):7700-8. PMID: 16784221

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