3OWU:
reference: Quantitative, directional measurement of electric field heterogeneity in the active site of ketosteroid isomerase., Fafarman AT, Sigala PA, Schwans JP, Fenn TD, Herschlag D, Boxer SG, Proc Natl Acad Sci U S A. 2012 Feb 7;109(6):E299-308. Epub 2012 Jan 17. PMID: 22308339

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