4ZXI:
reference: Structures of two distinct conformations of holo-non-ribosomal peptide synthetases., Drake EJ, Miller BR, Shi C, Tarrasch JT, Sundlov JA, Allen CL, Skiniotis G, Aldrich CC, Gulick AM, Nature. 2016 Jan 14;529(7585):235-8. doi: 10.1038/nature16163. PMID: 26762461

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