Protein Family Models

Date:

2024-08-14

This family includes the Diphtheria toxin repressor [1]. It acts as an iron-binding repressor of diphtheria toxin gene expression and may serve as a global regulator of gene expression. DTXR comprises an N-terminal DNA-binding domain, an interface domain (which contains two metal-binding sites) and a third, very flexible C-terminal domain. The second domain is responsible for dimerization and metal binding. Binding of DTXR to Tox operator requires a divalent metal ion such as cobalt, ferric, manganese and nickel whereas zinc shows weak activation [2]. This domain can also bind Cd(II), Ca(II) and Cu(II) (Matilla et. al., FEMS Microbiology Reviews, fuab043, 45, 2021, 1. https://doi.org/10.1093/femsre/fuab043). [1]. 7568230. Structures of the apo- and the metal ion-activated forms of the diphtheria tox repressor from Corynebacterium diphtheriae. Schiering N, Tao X, Zeng H, Murphy JR, Petsko GA, Ringe D;. Proc Natl Acad Sci USA 1995;92:9843-9850. [2]. 7743135. Three-dimensional structure of the diphtheria toxin repressor in complex with divalent cation co-repressors. Qiu X, Verlinde CL, Zhang S, Schmitt MP, Holmes RK, Hol WG;. Structure 1995;3:87-100. (from Pfam)

Date:

2024-10-16

The Mar proteins are involved in the multiple antibiotic resistance, a non-specific resistance system. The expression of the mar operon is controlled by a repressor, MarR. A large number of compounds induce transcription of the mar operon. This is thought to be due to the compound binding to MarR, and the resulting complex stops MarR binding to the DNA. With the MarR repression lost, transcription of the operon proceeds [1]. The structure of MarR is known [2] and shows MarR as a dimer with each subunit containing a winged-helix DNA binding motif. [1]. 9068629. The Salmonella typhimurium mar locus: molecular and genetic analyses and assessment of its role in virulence. Sulavik MC, Dazer M, Miller PF;. J Bacteriol 1997;179:1857-1866. [2]. 11473263. The crystal structure of MarR, a regulator of multiple antibiotic resistance, at 2.3 A resolution. Alekshun MN, Levy SB, Mealy TR, Seaton BA, Head JF;. Nat Struct Biol 2001;8:710-714. (from Pfam)

Date:

2024-10-16

This family includes the Diphtheria toxin repressor. DNA binding is through a helix-turn-helix motif. [1]. 7568230. Structures of the apo- and the metal ion-activated forms of the diphtheria tox repressor from Corynebacterium diphtheriae. Schiering N, Tao X, Zeng H, Murphy JR, Petsko GA, Ringe D;. Proc Natl Acad Sci USA 1995;92:9843-9850. [2]. 7743135. Three-dimensional structure of the diphtheria toxin repressor in complex with divalent cation co-repressors. Qiu X, Verlinde CL, Zhang S, Schmitt MP, Holmes RK, Hol WG;. Structure 1995;3:87-100. (from Pfam)

Date:

2024-10-16

manganese-binding transcriptional regulator MntR, in the presence of manganese, represses the expression of mntH and mntS, and up-regulates the expression of mntP

Date:

2019-07-29

Transcriptional regulator that represses the manganese transporter MntH when manganese is present

Gene:

mntR

Date:

2021-10-18