3R1B:
reference: Structural Analysis of Mammalian Cytochrome P450 2B4 Covalently Bound to the Mechanism-Based Inactivator tert-Butylphenylacetylene: Insight into Partial Enzymatic Activity., Gay SC, Zhang H, Wilderman PR, Roberts AG, Liu T, Li S, Lin HL, Zhang Q, Woods VL, Stout CD, Hollenberg PF, Halpert JR, Biochemistry. 2011 Apr 21. PMID: 21510666

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