Protein Family Models for Protein (Select 491851220) - Protein Family Models

Select item 4206771.

helix-turn-helix domain-containing protein

GO Terms:

Molecular Function:: DNA-binding transcription factor activity (GO:0003700)

Biological Process:: regulation of DNA-templated transcription (GO:0006355)

Molecular Function:: sequence-specific DNA binding (GO:0043565)

Date:: 2024-08-14

Family Accession:: NF024242.5
Method:: HMM

Select item 4137312.

AraC family ligand binding domain-containing protein

This family represents the arabinose-binding and dimerisation domain of the bacterial gene regulatory protein AraC. The domain is found in conjunction with the helix-turn-helix (HTH) DNA-binding motif Pfam:PF00165. This domain is distantly related to the Cupin domain Pfam:PF00190. [1]. 9103202. Structural basis for ligand-regulated oligomerization of AraC. Soisson SM, MacDougall-Shackleton B, Schleif R, Wolberger C;. Science 1997;276:421-425. (from Pfam)

GO Terms:

Biological Process:: regulation of DNA-templated transcription (GO:0006355)

Date:: 2024-10-16

Family Accession:: NF014376.5
Method:: HMM

Select item 4129623.

ARD/ARD' family

The two acireductone dioxygenase enzymes (ARD and ARD', previously known as E-2 and E-2') from Klebsiella pneumoniae share the same amino acid sequence Swiss:Q9ZFE7, but bind different metal ions: ARD binds Ni2+, ARD' binds Fe2+. ARD and ARD' can be experimentally interconverted by removal of the bound metal ion and reconstitution with the appropriate metal ion. The two enzymes share the same substrate, 1,2-dihydroxy-3-keto-5-(methylthio)pentene, but yield different products. ARD' yields the alpha-keto precursor of methionine (and formate), thus forming part of the ubiquitous methionine salvage pathway that converts 5'-methylthioadenosine (MTA) to methionine. This pathway is responsible for the tight control of the concentration of MTA, which is a powerful inhibitor of polyamine biosynthesis and transmethylation reactions [1,2]. ARD yields methylthiopropanoate, carbon monoxide and formate, and thus prevents the conversion of MTA to methionine. The role of the ARD catalysed reaction is unclear: methylthiopropanoate is cytotoxic, and carbon monoxide can activate guanylyl cyclase, leading to increased intracellular cGMP levels [1,2]. This family also contains other members, whose functions are not well characterised. [1]. 11371200. Mechanistic Studies of Two Dioxygenases in the Methionine Salvage Pathway of Klebsiella pneumoniae(,). Dai Y, Pochapsky TC, Abeles RH;. Biochemistry 2001;40:6379-6387. [2]. 9880484. One protein, two enzymes. Dai Y, Wensink PC, Abeles RH;. J Biol Chem 1999;274:1193-1195. (from Pfam)

GO Terms:

Molecular Function:: acireductone dioxygenase [iron(II)-requiring] activity (GO:0010309)

Date:: 2024-10-16

Family Accession:: NF015065.5
Method:: HMM

Select item 4012564.