Protein Family Models

Region 4 of sigma-70 like sigma-factors are involved in binding to the -35 promoter element via a helix-turn-helix motif [1]. [1]. 11931761. Structure of the bacterial RNA polymerase promoter specificity. sigma subunit.. Campbell EA, Muzzin O, Chlenov M, Sun JL, Olson CA, Weinman O,. Trester-Zedlitz ML, Darst SA;. Mol Cell 2002;9:527-539. (from Pfam)

Date:

2024-08-14

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. [1]. 11931761. Structure of the bacterial RNA polymerase promoter specificity. sigma subunit.. Campbell EA, Muzzin O, Chlenov M, Sun JL, Olson CA, Weinman O,. Trester-Zedlitz ML, Darst SA;. Mol Cell 2002;9:527-539. (from Pfam)

Date:

2024-08-14

This HMM hits a core region shared by multiple sigma factors, interchangeable subunits that complete the RNA polymerase holoenzyme and allow transcription to start. In E. coli K-12 alone, this HMM hits RpoD (sigma-70), RpoH (sigma-32), FliA (sigma-28), FecI (sigma-19), RpoS, and RpoE.

Date:

2024-08-14

This group of sigma factors are members of the sigma-70 family (TIGR02937) and are found primarily in the genus Bacteroides. This family appears to have resulted from a lineage-specific expansion as B. thetaiotaomicron VPI-5482, Bacteroides forsythus ATCC 43037, Bacteroides fragilis YCH46 and Bacteroides fragilis NCTC 9343 contain 25, 12, 24 and 23 members, respectively. There are currentlyonly two known members of this family outside of the Bacteroides, in Rhodopseudomonas and Bradyrhizobium.

Date:

2021-07-30

This model encompasses all varieties of the sigma-70 type sigma factors including the ECF subfamily. A number of sigma factors have names with a different number than 70 (i.e. sigma-38), but in fact, all except for the Sigma-54 family (TIGR02395) are included within this family. Several PFAM models hit segments of these sequences including Sigma-70 region 2 (PF04542) and Sigma-70, region 4 (PF04545), but not always above their respective trusted cutoffs.

Date:

2024-06-27