Anti-sigma factor A is a transcriptional inhibitor that inhibits sigma 70-directed transcription by weakening its interaction with the core of the host's RNA polymerase. It is an all-helical protein, composed of six helical segments and intervening l ...
Anti-sigma factor A is a transcriptional inhibitor that inhibits sigma 70-directed transcription by weakening its interaction with the core of the host's RNA polymerase. It is an all-helical protein, composed of six helical segments and intervening loops and turns, as well as a helix-turn-helix DNA binding motif, although neither free anti-sigma factor nor anti-sigma factor bound to sigma-70 has been shown to interact directly with DNA. In solution, the protein forms a symmetric dimer of small (10.59 kDa) protomers, which are composed of helix and coil regions and are devoid of beta-strand/sheet secondary structural elements [1].
Region 4 of sigma-70 like sigma-factors are involved in binding to the -35 promoter element via a helix-turn-helix motif [1]. Due to the way Pfam works, the threshold has been set artificially high to prevent overlaps with other helix-turn-helix fami ...
Region 4 of sigma-70 like sigma-factors are involved in binding to the -35 promoter element via a helix-turn-helix motif [1]. Due to the way Pfam works, the threshold has been set artificially high to prevent overlaps with other helix-turn-helix families. Therefore there are many false negatives.
