1QW1:
reference: Prolylpeptide binding by the prokaryotic SH3-like domain of the diphtheria toxin repressor: a regulatory switch., Wylie GP, Rangachari V, Bienkiewicz EA, Marin V, Bhattacharya N, Love JF, Murphy JR, Logan TM, Biochemistry 2005 Jan 11;44(1):40-51. PMID: 15628844

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