Protein Family Models

AdoCbl-dependent diol dehydratase (DD) (EC 4.2.1.28) is one of the enzymes that catalyzes the conversion of 1,2-propanediol, 1,2-ethanediol, and glycerol to the corresponding aldehydes. A DD-reactivating factor (DDR) is responsible for the rapid reactivation of the inactivated holoDD in the presence of AdoCbl, ATP, and Mg2+. DDR exists as a dimer of heterodimer (alpha-beta)2. The alpha subunit has four domains: ATPase domain, swiveling domain, linker domain, and insert domain. The beta subunit, composed of a single domain, has a similar fold to the beta subunit of diol dehydratase (DD). This entry describes the swiveling domain of DDR, which structurally connects the beta subunit and the ATPase domain of the other alpha subunit. Furthermore, the beta subunit moves with the swiveling domain while the linker domain acts as a flat spring or a hinge for the domain movement of the swiveling domain [1]. [1]. 16338403. Release of a damaged cofactor from a coenzyme B12-dependent enzyme: X-ray structures of diol dehydratase-reactivating factor. Shibata N, Mori K, Hieda N, Higuchi Y, Yamanishi M, Toraya T;. Structure. 2005;13:1745-1754. (from Pfam)

Date:

2024-10-16

Diol dehydratase (DDH, EC:4.2.1.28) and its isofunctional homologue glycerol dehydratase (GDH, EC.4.2.1.30) are enzymes which catalyse the conversion of glycerol 1,2-propanediol, and 1,2-ethanediol to aldehydes [1]. These reactions require coenzyme B12. Cleavage of the Co-C bond of coenzyme B12 by substrates or coenzyme analogues results in inactivation during which coenzyme B12 remains tightly bound to the apoenzyme. This family comprises of the large subunit of the diol dehydratase and glycerol dehydratase reactivating factors whose function is to reactivate the holoenzyme by exchange of a damaged cofactor for intact coenzyme. [1]. 9990728. Biochemistry of coenzyme B12-dependent glycerol and diol dehydratases and organization of the encoding genes. Daniel R, Bobik TA, Gottschalk G;. FEMS Microbiol Rev. 1998;22:553-566. [2]. 16338403. Release of a damaged cofactor from a coenzyme B12-dependent enzyme: X-ray structures of diol dehydratase-reactivating factor. Shibata N, Mori K, Hieda N, Higuchi Y, Yamanishi M, Toraya T;. Structure. 2005;13:1745-1754. (from Pfam)

Date:

2024-10-16

Members of this family are the alpha (large) subunit of the alpha-2/beta-2 tetrameric enzyme that reactivates B12-dependent trimeric diol dehydratases (1,2-propanediol dehydratase, glycerol dehydratase). Note that the beta subunit of the reactivase is homologous to the beta (medium) subunit of the diol dehydratase. The reactivase catalyzes the exchange of chemically inactivated B-12 for active B12. This model excludes homologs from Mycobacterium (e.g. M. smegmatis), where the several paralogous forms of the dehydratase occur and are exceptional also by not being found in a carboxysome-like microcompartment.

Date:

2019-09-10

reactive_PduG family protein

Date:

2017-03-02