2B96:
reference: Third calcium ion found in an inhibitor-bound phospholipase A2., Sekar K, Gayathri D, Velmurugan D, Jeyakanthan J, Yamane T, Poi MJ, Tsai MD, Acta Crystallogr D Biol Crystallogr. 2006 Apr;62(Pt 4):392-7. Epub 2006, Mar 18. PMID: 16552140

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