1MDB:
reference: Crystal structure of DhbE, an archetype for aryl acid activating domains of modular nonribosomal peptide synthetases., May JJ, Kessler N, Marahiel MA, Stubbs MT, Proc Natl Acad Sci U S A 2002 Sep 17;99(19):12120-5. PMID: 12221282

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