5SW4:
reference: A molecular switch and electronic circuit modulate catalase activity in catalase-peroxidases., Carpena X, Wiseman B, Deemagarn T, Singh R, Switala J, Ivancich A, Fita I, Loewen PC, EMBO Rep. 2005 Dec;6(12):1156-62. PMID: 16211084

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