1NNS:
reference: Structural comparison of Escherichia coli L-asparaginase in two monoclinic space groups., Sanches M, Barbosa J JA, De Oliveira RT, Abrahao Neto J, Polikarpov I, Acta Crystallogr D Biol Crystallogr 2003 Mar;59(Pt 3):416-22. PMID: 12595697

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