Protein Family Models

Date:

2024-08-14

This family contains the small molecule binding domain of a number of different bacterial transcription activators [1]. This family also contains DNA gyrase inhibitors. The GyrI superfamily contains a diad of the SHS2 module, adapted for small-molecule binding [3]. The GyrI superfamily includes a family of secreted forms that is found only in animals and the bacterial pathogen Leptospira [3]. [1]. 10802742. Crystal structure of the Escherichia coli Rob transcription factor in complex with DNA. Kwon HJ, Bennik MH, Demple B, Ellenberger T;. Nat Struct Biol 2000;7:424-430. [2]. 11948793. Crystal structure of the Escherichia coli SbmC protein that protects cells from the DNA replication inhibitor microcin B17. Romanowski MJ, Gibney SA, Burley SK;. Proteins 2002;47:403-407. [3]. 15281131. The SHS2 module is a common structural theme in functionally diverse protein groups, like Rpb7p, FtsA, GyrI, and MTH1598/TM1083 superfamilies. Anantharaman V, Aravind L;. Proteins. 2004;56:795-807. (from Pfam)

Date:

2024-10-16

In the absence of arabinose, the N-terminal arm of AraC binds to the DNA binding domain (Pfam:PF00165) and helps to hold the two DNA binding domains in a relative orientation that favours DNA looping. In the presence of arabinose, the arms bind over the arabinose on the dimerisation domain, thus freeing the DNA-binding domains. The freed DNA-binding domains are then able to assume a conformation suitable for binding to the adjacent DNA sites that are utilised when AraC activates transcription, and hence AraC ceases looping the DNA when arabinose is added [1-2]. [1]. 9600836. Apo-AraC actively seeks to loop. Seabold RR, Schleif RF;. J Mol Biol 1998;278:529-538. [2]. 9600837. Arm-domain interactions in AraC. Saviola B, Seabold R, Schleif RF;. J Mol Biol 1998;278:539-548. (from Pfam)

Date:

2024-10-16