2GPE:
reference: Crystal structures of the DNA-binding domain of Escherichia coli proline utilization A flavoprotein and analysis of the role of Lys9 in DNA recognition., Larson JD, Jenkins JL, Schuermann JP, Zhou Y, Becker DF, Tanner JJ, Protein Sci. 2006 Nov;15(11):2630-41. Epub 2006 Sep 25. PMID: 17001030

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