| 3G2B: reference: Xanthomonas campestris PqqD in the pyrroloquinoline quinone biosynthesis operon adopts a novel saddle-like fold that possibly serves as a PQQ carrier., Tsai TY, Yang CY, Shih HL, Wang AH, Chou SH, Proteins. 2009 Sep;76(4):1042-8. PMID: 19475705 |
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