4RYI:
reference: Protein structure. Structure and activity of tryptophan-rich TSPO proteins., Guo Y, Kalathur RC, Liu Q, Kloss B, Bruni R, Ginter C, Kloppmann E, Rost B, Hendrickson WA, Science. 2015 Jan 30;347(6221):551-5. doi: 10.1126/science.aaa1534. PMID: 25635100

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