1A6J:
reference: The three-dimensional structure of the nitrogen regulatory protein IIANtr from Escherichia coli., Bordo D, van Monfort RL, Pijning T, Kalk KH, Reizer J, Saier MH Jr, Dijkstra BW, J Mol Biol 1998 May 29;279(1):245-55. PMID: 9636714

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