5BPJ:
reference: All Ca(2+)-binding loops of light-sensitive ctenophore photoprotein berovin bind magnesium ions: The spatial structure of Mg(2+)-loaded apo-berovin., Burakova LP, Natashin PV, Malikova NP, Niu F, Pu M, Vysotski ES, Liu ZJ, J Photochem Photobiol B. 2016 Jan;154:57-66. doi:, 10.1016/j.jphotobiol.2015.11.012. Epub 2015 Dec 2. PMID: 26690016

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