5V30:
reference: Nitrosative stress sensing in Porphyromonas gingivalis: structure of and heme binding by the transcriptional regulator HcpR., Belvin BR, Musayev FN, Burgner J, Scarsdale JN, Escalante CR, Lewis JP, Acta Crystallogr D Struct Biol. 2019 Apr 1;75(Pt 4):437-450. doi:, 10.1107/S205979831900264X. Epub 2019 Apr 5. PMID: 30988260

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