3BOF:
reference: Metal active site elasticity linked to activation of homocysteine in methionine synthases., Koutmos M, Pejchal R, Bomer TM, Matthews RG, Smith JL, Ludwig ML, Proc Natl Acad Sci U S A. 2008 Mar 4;105(9):3286-91. Epub 2008 Feb 22. PMID: 18296644

This OCA Structure page
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