3A3U:
reference: Crystal structure of MqnD (TTHA1568), a menaquinone biosynthetic enzyme from Thermus thermophilus HB8., Arai R, Murayama K, Uchikubo-Kamo T, Nishimoto M, Toyama M, Kuramitsu S, Terada T, Shirouzu M, Yokoyama S, J Struct Biol. 2009 Dec;168(3):575-81. Epub 2009 Jul 12. PMID: 19602440

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