4MGR:
reference: Crystal structure of Bacillus subtilis GabR, an autorepressor and transcriptional activator of gabT., Edayathumangalam R, Wu R, Garcia R, Wang Y, Wang W, Kreinbring CA, Bach A, Liao J, Stone TA, Terwilliger TC, Hoang QQ, Belitsky BR, Petsko GA, Ringe D, Liu D, Proc Natl Acad Sci U S A. 2013 Oct 14. PMID: 24127574

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