C-terminal, alpha helical domain of Ure2p and related Glutathione S-transferase-like proteins
Glutathione S-transferase (GST) C-terminal domain family, Ure2p-like subfamily; composed of the Saccharomyces cerevisiae Ure2p, YfcG and YghU from Escherichia coli, and related GST-like proteins. Ure2p is a regulator for nitrogen catabolism in yeast. It represses the expression of several gene products involved in the use of poor nitrogen sources when rich sources are available. A transmissible conformational change of Ure2p results in a prion called [Ure3], an inactive, self-propagating and infectious amyloid. Ure2p displays a GST fold containing an N-terminal thioredoxin-fold domain and a C-terminal alpha helical domain. The N-terminal thioredoxin-fold domain is sufficient to induce the [Ure3] phenotype and is also called the prion domain of Ure2p. In addition to its role in nitrogen regulation, Ure2p confers protection to cells against heavy metal ion and oxidant toxicity, and shows glutathione (GSH) peroxidase activity. YfcG and YghU are two of the nine GST homologs in the genome of Escherichia coli. They display very low or no GSH transferase, but show very good disulfide bond oxidoreductase activity. YghU also shows modest organic hydroperoxide reductase activity. GSTs are cytosolic dimeric proteins involved in cellular detoxification by catalyzing the conjugation of GSH with a wide range of endogenous and xenobiotic alkylating agents, including carcinogens, therapeutic drugs, environmental toxins and products of oxidative stress. GSTs also show GSH peroxidase activity and are involved in the synthesis of prostaglandins and leukotrienes. The GST active site is located in a cleft between the N- and C-terminal domains. GSH binds to the N-terminal domain while the hydrophobic substrate occupies a pocket in the C-terminal domain.
Jiyao W et al.(2023). "The conserved domain database in 2023.",