Protein Disulfide Oxidoreductases and Other Proteins with a Thioredoxin fold; The thioredoxin (TRX)-like superfamily is a large, diverse group of proteins containing a TRX fold. Many members contain a classic TRX domain with a redox active CXXC motif. They function as protein disulfide oxidoreductases (PDOs), altering the redox state of target proteins via the reversible oxidation of their active site dithiol. The PDO members of this superfamily include the families of TRX, protein disulfide isomerase (PDI), tlpA, glutaredoxin, NrdH redoxin, and bacterial Dsb proteins (DsbA, DsbC, DsbG, DsbE, DsbDgamma). Members of the superfamily that do not function as PDOs but contain a TRX-fold domain include phosducins, peroxiredoxins, glutathione (GSH) peroxidases, SCO proteins, GSH transferases (GST, N-terminal domain), arsenic reductases, TRX-like ferredoxins and calsequestrin, among others.

                         10        20        30
                 ....*....|....*....|....*....|....
gi 767939851  12 HLLFQQVPMVEIDGMKLVQTRSILHYIADKHNLF 45
Cdd:cd03077   46 SLMFQQVPMVEIDGMKLVQTRAILNYIAGKYNLY 79

Glutathione S-transferase, C-terminal domain; This domain is closely related to pfam00043.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767939851   64 DLLELLIMHPFLKPDDQQKEVVNM-AQKAIIRYFPVFEKILRGHGQSFLVGNQLSLADVILLQTILALEEKI-PNILSAF 141
Cdd:pfam14497   2 DLHHPIASSLYYEDEKKKAKRRKEfREERLPKFLGYFEKVLNKNGGGYLVGDKLTYADLALFQVLDGLLYPKaPDALDKY 81

                          90       100
                  ....*....|....*....|.
gi 767939851  142 PFLQEYTVKLSNIPTIKRFLE 162
Cdd:pfam14497  82 PKLKALHERVAARPNIKAYLA 102

GST_N family, Class Alpha subfamily; GSTs are cytosolic dimeric proteins involved in cellular detoxification by catalyzing the conjugation of glutathione (GSH) with a wide range of endogenous and xenobiotic alkylating agents, including carcinogens, therapeutic drugs, environmental toxins and products of oxidative stress. The GST fold contains an N-terminal TRX-fold domain and a C-terminal alpha helical domain, with an active site located in a cleft between the two domains. The class Alpha subfamily is composed of eukaryotic GSTs which can form homodimer and heterodimers. There are at least six types of class Alpha GST subunits in rats, four of which have human counterparts, resulting in many possible isoenzymes with different activities, tissue distribution and substrate specificities. Human GSTA1-1 and GSTA2-2 show high GSH peroxidase activity. GSTA3-3 catalyzes the isomerization of intermediates in steroid hormone biosynthesis. GSTA4-4 preferentially catalyzes the GSH conjugation of alkenals.

                         10        20        30
                 ....*....|....*....|....*....|....
gi 767939851  12 HLLFQQVPMVEIDGMKLVQTRSILHYIADKHNLF 45
Cdd:cd03077   46 SLMFQQVPMVEIDGMKLVQTRAILNYIAGKYNLY 79

Glutathione S-transferase, N-terminal domain; Function: conjugation of reduced glutathione to a variety of targets. Also included in the alignment, but not GSTs: S-crystallins from squid (similarity to GST previously noted); eukaryotic elongation factors 1-gamma (not known to have GST activity and similarity not previously recognized); HSP26 family of stress-related proteins including auxin-regulated proteins in plants and stringent starvation proteins in E. coli (not known to have GST activity and similarity not previously recognized). The glutathione molecule binds in a cleft between the N- and C-terminal domains - the catalytically important residues are proposed to reside in the N-terminal domain.

                          10        20
                  ....*....|....*....|....*.
gi 767939851   15 FQQVPMVEIDGMKLVQTRSILHYIAD 40
Cdd:pfam02798  51 LGKVPALEDGGKKLTESRAILEYIAR 76

Glutathione S-transferase, C-terminal domain; This domain is closely related to pfam00043.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767939851   64 DLLELLIMHPFLKPDDQQKEVVNM-AQKAIIRYFPVFEKILRGHGQSFLVGNQLSLADVILLQTILALEEKI-PNILSAF 141
Cdd:pfam14497   2 DLHHPIASSLYYEDEKKKAKRRKEfREERLPKFLGYFEKVLNKNGGGYLVGDKLTYADLALFQVLDGLLYPKaPDALDKY 81

                          90       100
                  ....*....|....*....|.
gi 767939851  142 PFLQEYTVKLSNIPTIKRFLE 162
Cdd:pfam14497  82 PKLKALHERVAARPNIKAYLA 102

GST_N family, Class Alpha subfamily; GSTs are cytosolic dimeric proteins involved in cellular detoxification by catalyzing the conjugation of glutathione (GSH) with a wide range of endogenous and xenobiotic alkylating agents, including carcinogens, therapeutic drugs, environmental toxins and products of oxidative stress. The GST fold contains an N-terminal TRX-fold domain and a C-terminal alpha helical domain, with an active site located in a cleft between the two domains. The class Alpha subfamily is composed of eukaryotic GSTs which can form homodimer and heterodimers. There are at least six types of class Alpha GST subunits in rats, four of which have human counterparts, resulting in many possible isoenzymes with different activities, tissue distribution and substrate specificities. Human GSTA1-1 and GSTA2-2 show high GSH peroxidase activity. GSTA3-3 catalyzes the isomerization of intermediates in steroid hormone biosynthesis. GSTA4-4 preferentially catalyzes the GSH conjugation of alkenals.

                         10        20        30
                 ....*....|....*....|....*....|....
gi 767939851  12 HLLFQQVPMVEIDGMKLVQTRSILHYIADKHNLF 45
Cdd:cd03077   46 SLMFQQVPMVEIDGMKLVQTRAILNYIAGKYNLY 79

Glutathione S-transferase [Posttranslational modification, protein turnover, chaperones];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767939851  15 FQQVPMVEIDGMKLVQTRSILHYIADKH---NLFGKNLKERTLIDM---YVEGTLDLLELLIMHPFLKPDDQqkEVVNMA 88
Cdd:COG0625   50 LGKVPVLVDDGLVLTESLAILEYLAERYpepPLLPADPAARARVRQwlaWADGDLHPALRNLLERLAPEKDP--AAIARA 127

                         90       100       110       120       130       140       150
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 767939851  89 QKAIIRYFPVFEKILRGHGqsFLVGNQLSLADVILLQTILALEE-KIPniLSAFPFLQEYTVKLSNIPTIKRFLEPG 164
Cdd:COG0625  128 RAELARLLAVLEARLAGGP--YLAGDRFSIADIALAPVLRRLDRlGLD--LADYPNLAAWLARLAARPAFQRALAAA 200

Glutathione S-transferase, C-terminal domain; GST conjugates reduced glutathione to a variety of targets including S-crystallin from squid, the eukaryotic elongation factor 1-gamma, the HSP26 family of stress-related proteins and auxin-regulated proteins in plants. Stringent starvation proteins in E. coli are also included in the alignment but are not known to have GST activity. The glutathione molecule binds in a cleft between N and C-terminal domains. The catalytically important residues are proposed to reside in the N-terminal domain. In plants, GSTs are encoded by a large gene family (48 GST genes in Arabidopsis) and can be divided into the phi, tau, theta, zeta, and lambda classes.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767939851   73 PFLKPDDQQKEVVNMAQKAIIRYFPVFEKILRGHGqsFLVGNQLSLADVILLQTILALEEKIPNILS-AFPFLQEYTVKL 151
Cdd:pfam00043  12 PYVPPEEKKEPEVDEALEKVARVLSALEEVLKGQT--YLVGDKLTLADIALAPALLWLYELDPACLReKFPNLKAWFERV 89

                  ....
gi 767939851  152 SNIP 155
Cdd:pfam00043  90 AARP 93

GST_N family, Class Sigma_like; composed of GSTs belonging to class Sigma and similar proteins, including GSTs from class Mu, Pi and Alpha. GSTs are cytosolic dimeric proteins involved in cellular detoxification by catalyzing the conjugation of glutathione (GSH) with a wide range of endogenous and xenobiotic alkylating agents, including carcinogens, therapeutic drugs, environmental toxins and products of oxidative stress. The GST fold contains an N-terminal TRX-fold domain and a C-terminal alpha helical domain, with an active site located in a cleft between the two domains. Vertebrate class Sigma GSTs are characterized as GSH-dependent hematopoietic prostaglandin (PG) D synthases and are responsible for the production of PGD2 by catalyzing the isomerization of PGH2. The functions of PGD2 include the maintenance of body temperature, inhibition of platelet aggregation, bronchoconstriction, vasodilation and mediation of allergy and inflammation. Other class Sigma members include the class II insect GSTs, S-crystallins from cephalopods and 28-kDa GSTs from parasitic flatworms. Drosophila GST2 is associated with indirect flight muscle and exhibits preference for catalyzing GSH conjugation to lipid peroxidation products, indicating an anti-oxidant role. S-crystallin constitutes the major lens protein in cephalopod eyes and is responsible for lens transparency and proper refractive index. The 28-kDa GST from Schistosoma is a multifunctional enzyme, exhibiting GSH transferase, GSH peroxidase and PGD2 synthase activities, and may play an important role in host-parasite interactions. Also members are novel GSTs from the fungus Cunninghamella elegans, designated as class Gamma, and from the protozoan Blepharisma japonicum, described as a light-inducible GST.

                         10        20
                 ....*....|....*....|....*...
gi 767939851  13 LLFQQVPMVEIDGMKLVQTRSILHYIAD 40
Cdd:cd03039   45 LPFGQLPVLEIDGKKLTQSNAILRYLAR 72

Glutathione S-transferase, N-terminal domain; Function: conjugation of reduced glutathione to a variety of targets. Also included in the alignment, but not GSTs: S-crystallins from squid (similarity to GST previously noted); eukaryotic elongation factors 1-gamma (not known to have GST activity and similarity not previously recognized); HSP26 family of stress-related proteins including auxin-regulated proteins in plants and stringent starvation proteins in E. coli (not known to have GST activity and similarity not previously recognized). The glutathione molecule binds in a cleft between the N- and C-terminal domains - the catalytically important residues are proposed to reside in the N-terminal domain.

                          10        20
                  ....*....|....*....|....*.
gi 767939851   15 FQQVPMVEIDGMKLVQTRSILHYIAD 40
Cdd:pfam02798  51 LGKVPALEDGGKKLTESRAILEYIAR 76

C-terminal, alpha helical domain of the Glutathione S-transferase family; Glutathione S-transferase (GST) family, C-terminal alpha helical domain; a large, diverse group of cytosolic dimeric proteins involved in cellular detoxification by catalyzing the conjugation of glutathione (GSH) with a wide range of endogenous and xenobiotic alkylating agents, including carcinogens, therapeutic drugs, environmental toxins and products of oxidative stress. In addition, GSTs also show GSH peroxidase activity and are involved in the synthesis of prostaglandins and leukotrienes. This family, also referred to as soluble GSTs, is the largest family of GSH transferases and is only distantly related to the mitochondrial GSTs (GSTK). Soluble GSTs bear no structural similarity to microsomal GSTs (MAPEG family) and display additional activities unique to their group, such as catalyzing thiolysis, reduction and isomerization of certain compounds. The GST fold contains an N-terminal thioredoxin-fold domain and a C-terminal alpha helical domain, with an active site located in a cleft between the two domains. GSH binds to the N-terminal domain while the hydrophobic substrate occupies a pocket in the C-terminal domain. Based on sequence similarity, different classes of GSTs have been identified, which display varying tissue distribution, substrate specificities and additional specific activities. In humans, GSTs display polymorphisms which may influence individual susceptibility to diseases such as cancer, arthritis, allergy and sclerosis. Some GST family members with non-GST functions include glutaredoxin 2, the CLIC subfamily of anion channels, prion protein Ure2p, crystallins, metaxins, stringent starvation protein A, and aminoacyl-tRNA synthetases.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767939851  58 YVEGTLDLLELLIMHPFLKPDDQQKEVVNMAQKAIIRYFPVFEKILRGHGqsFLVGNQLSLADVILLQTILALE--EKIP 135
Cdd:cd00299    7 WADATLAPPLVRLLYLEKVPLPKDEAAVEAAREELPALLAALEQLLAGRP--YLAGDQFSLADVALAPVLARLEalGPYY 84

                         90
                 ....*....|..
gi 767939851 136 NILSAFPFLQEY 147
Cdd:cd00299   85 DLLDEYPRLKAW 96

Glutathione S-transferase C-terminal-like, alpha helical domain of the Gamma subunit of Elongation Factor 1B and similar proteins; Glutathione S-transferase (GST) C-terminal domain family, Gamma subunit of Elongation Factor 1B (EF1Bgamma) subfamily; EF1Bgamma is part of the eukaryotic translation elongation factor-1 (EF1) complex which plays a central role in the elongation cycle during protein biosynthesis. EF1 consists of two functionally distinct units, EF1A and EF1B. EF1A catalyzes the GTP-dependent binding of aminoacyl-tRNA to the ribosomal A site concomitant with the hydrolysis of GTP. The resulting inactive EF1A:GDP complex is recycled to the active GTP form by the guanine-nucleotide exchange factor EF1B, a complex composed of at least two subunits, alpha and gamma. Metazoan EFB1 contain a third subunit, beta. The EF1B gamma subunit contains a GST fold consisting of an N-terminal thioredoxin-fold domain and a C-terminal alpha helical domain. The GST-like domain of EF1Bgamma is believed to mediate the dimerization of the EF1 complex, which in yeast is a dimer of the heterotrimer EF1A:EF1Balpha:EF1Bgamma. In addition to its role in protein biosynthesis, EF1Bgamma may also display other functions. The recombinant rice protein has been shown to possess GSH conjugating activity. The yeast EF1Bgamma binds to membranes in a calcium dependent manner and is also part of a complex that binds to the msrA (methionine sulfoxide reductase) promoter suggesting a function in the regulation of its gene expression. Also included in this subfamily is the GST_C-like domain at the N-terminus of human valyl-tRNA synthetase (ValRS) and its homologs. Metazoan ValRS forms a stable complex with Elongation Factor-1H (EF-1H), and together, they catalyze consecutive steps in protein biosynthesis, tRNA aminoacylation and its transfer to EF.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 767939851  82 KEVVNMAQKAIIRYFPVFEKILRGHgqSFLVGNQLSLADVI-------LLQTILALE--EKIPNI 137
Cdd:cd03181   35 KKAVDKAKEDLKRALGVLEEHLLTR--TYLVGERITLADIFvasallrGFETVLDPEfrKKYPNV 97

GST_N family, Class Mu subfamily; GSTs are cytosolic dimeric proteins involved in cellular detoxification by catalyzing the conjugation of glutathione (GSH) with a wide range of endogenous and xenobiotic alkylating agents, including carcinogens, therapeutic drugs, environmental toxins and products of oxidative stress. The GST fold contains an N-terminal TRX-fold domain and a C-terminal alpha helical domain, with an active site located in a cleft between the two domains. The class Mu subfamily is composed of eukaryotic GSTs. In rats, at least six distinct class Mu subunits have been identified, with homologous genes in humans for five of these subunits. Class Mu GSTs can form homodimers and heterodimers, giving a large number of possible isoenzymes that can be formed, all with overlapping activities but different substrate specificities. They are the most abundant GSTs in human liver, skeletal muscle and brain, and are believed to provide protection against diseases including cancer and neurodegenerative disorders. Some isoenzymes have additional specific functions. Human GST M1-1 acts as an endogenous inhibitor of ASK1 (apoptosis signal-regulating kinase 1), thereby suppressing ASK1-mediated cell death. Human GSTM2-2 and 3-3 have been identified as prostaglandin E2 synthases in the brain and may play crucial roles in temperature and sleep-wake regulation.

                         10        20        30
                 ....*....|....*....|....*....|
gi 767939851  13 LLFQQVPMVEIDGMKLVQTRSILHYIADKH 42
Cdd:cd03075   53 LDFPNLPYYIDGDVKLTQSNAILRYIARKH 82