1SKP:
reference: Nuclear magnetic resonance structure of d(GCATATGATAG). d(CTATCATATGC): a consensus sequence for promoters recognized by sigma K RNA polymerase., Tonelli M, Ragg E, Bianucci AM, Lesiak K, James TL, Biochemistry 1998 Aug 25;37(34):11745-61. PMID: 9718297

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