5XMJ:
reference: Structural insights into the electron/proton transfer pathways in the quinol:fumarate reductase from Desulfovibrio gigas., Guan HH, Hsieh YC, Lin PJ, Huang YC, Yoshimura M, Chen LY, Chen SK, Chuankhayan P, Lin CC, Chen NC, Nakagawa A, Chan SI, Chen CJ, Sci Rep. 2018 Oct 8;8(1):14935. doi: 10.1038/s41598-018-33193-5. PMID: 30297797

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