3QOD:
reference: Structure of transcription factor HetR required for heterocyst differentiation in cyanobacteria., Kim Y, Joachimiak G, Ye Z, Binkowski TA, Zhang R, Gornicki P, Callahan SM, Hess WR, Haselkorn R, Joachimiak A, Proc Natl Acad Sci U S A. 2011 Jun 21;108(25):10109-14. Epub 2011 May 31. PMID: 21628585

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