helix_turn_helix, mercury resistance
SMART accession number:SM00422
Interpro abstract (IPR000551):

The many bacterial transcription regulation proteins which bind DNA through a 'helix-turn-helix' motif can be classified into subfamilies on the basis of sequence similarities. One of these is the MerR subfamily. MerR, which is found in many bacterial species mediates the mercuric-dependent induction of the mercury resistance operon. In the absence of mercury merR represses transcription by binding tightly, as a dimer, to the 'mer' operator region; when mercury is present the dimeric complex binds a single ion and becomes a potent transcriptional activator, while remaining bound to the mer site. Members of the family include the mercuric resistance operon regulatory protein merR; Bacillus subtilis bltR and bmrR; Bacillus glnR; Streptomyces coelicolor hspR; Bradyrhizobium japonicum nolA; Escherichia coli superoxide response regulator soxR; and Streptomyces lividans transcriptional activator tipA [(PUBMED:7688297), (PUBMED:2492496), (PUBMED:7608059), (PUBMED:1677938), (PUBMED:1988958), (PUBMED:2305262)]. Other members include hypothetical proteins from E. coli, B. subtilis and Haemophilus influenzae. Within this family, the HTH motif is situated towards the N terminus.

GO process:regulation of transcription, DNA-dependent (GO:0006355)
GO function:sequence-specific DNA binding transcription factor activity (GO:0003700)
Family alignment:
View or

There are 7663 HTH_MERR domains in 7569 proteins in SMART's nrdb database.

Click on the following links for more information.