4EPK:
reference: Evidence for a Dual Role of an Active Site Histidine in alpha-Amino-beta-carboxymuconate-epsilon-semialdehyde Decarboxylase., Huo L, Fielding AJ, Chen Y, Li T, Iwaki H, Hosler JP, Chen L, Hasegawa Y, Que L Jr, Liu A, Biochemistry. 2012 Jul 24;51(29):5811-21. Epub 2012 Jul 12. PMID: 22746257

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