5KHD:
reference: Tetrameric c-di-GMP mediates effective transcription factor dimerization to control Streptomyces development., Tschowri N, Schumacher MA, Schlimpert S, Chinnam NB, Findlay KC, Brennan RG, Buttner MJ, Cell. 2014 Aug 28;158(5):1136-47. doi: 10.1016/j.cell.2014.07.022. PMID: 25171413

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