3N2O:
reference: Evolution of substrate specificity within a diverse family of beta/alpha-barrel-fold basic amino acid decarboxylases: X-ray structure determination of enzymes with specificity for L-arginine and carboxynorspermidine., Deng X, Lee J, Michael AJ, Tomchick DR, Goldsmith EJ, Phillips MA, J Biol Chem. 2010 Aug 13;285(33):25708-19. Epub 2010 Jun 8. PMID: 20534592

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