4LKM:
reference: Exploring the binding nature of pyrrolidine pocket-dependent interactions in the polo-box domain of polo-like kinase 1., Murugan RN, Ahn M, Lee WC, Kim HY, Song JH, Cheong C, Hwang E, Seo JH, Shin SY, Choi SH, Park JE, Bang JK, PLoS One. 2013 Nov 6;8(11):e80043. doi: 10.1371/journal.pone.0080043. PMID: 24223211

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