1H61:
reference: Crystal structure of pentaerythritol tetranitrate reductase: "flipped" binding geometries for steroid substrates in different redox states of the enzyme., Barna TM, Khan H, Bruce NC, Barsukov I, Scrutton NS, Moody PC, J Mol Biol 2001 Jul 6;310(2):433-47. PMID: 11428899

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