3UTL:
reference: An analysis of subdomain orientation, conformational change and disorder in relation to crystal packing of aspartic proteinases., Bailey D, Carpenter EP, Coker A, Coker S, Read J, Jones AT, Erskine P, Aguilar CF, Badasso M, Toldo L, Rippmann F, Sanz-Aparicio J, Albert A, Blundell TL, Roberts NB, Wood SP, Cooper JB, Acta Crystallogr D Biol Crystallogr. 2012 May;68(Pt 5):541-52. Epub 2012 Apr 17. PMID: 22525752

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