6GQ8:
reference: Insights into the structures of superoxide reductases from the symbionts Ignicoccus hospitalis and Nanoarchaeum equitans., Romao CV, Matias PM, Sousa CM, Pinho FG, Pinto AF, Teixeira M, Bandeiras TM, Biochemistry. 2018 Jun 25. doi: 10.1021/acs.biochem.8b00334. PMID: 29939726

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