C-terminal, alpha helical domain of Class Mu Glutathione S-transferases; Glutathione S-transferase (GST) C-terminal domain 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 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. 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        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 6680121   92 EERIRVDILENQAMDTRIQLAMVCYSPDFEKKKPEYLEGLPEKMKLYSEFLGKQPWFAGNKVTYVDFLVYDVLDQHRIFE 171
Cdd:cd03209   1 KERIRVDMLEQQAMDLRMGLIRICYSPDFEKLKPDYLEKLPDKLKLFSEFLGDRPWFAGDKITYVDFLLYEALDQHRIFE 80

                        90       100       110       120
                ....*....|....*....|....*....|....*....|.
gi 6680121  172 PKCLDAFPNLKDFMGRFEGLKKISDYMKSSRFLSKPIFAKM 212
Cdd:cd03209  81 PDCLDAFPNLKDFLERFEALPKISAYMKSDRFIKWPINGWK 121

C-terminal, alpha helical domain of Class Mu Glutathione S-transferases; Glutathione S-transferase (GST) C-terminal domain 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 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. 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        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 6680121   92 EERIRVDILENQAMDTRIQLAMVCYSPDFEKKKPEYLEGLPEKMKLYSEFLGKQPWFAGNKVTYVDFLVYDVLDQHRIFE 171
Cdd:cd03209   1 KERIRVDMLEQQAMDLRMGLIRICYSPDFEKLKPDYLEKLPDKLKLFSEFLGDRPWFAGDKITYVDFLLYEALDQHRIFE 80

                        90       100       110       120
                ....*....|....*....|....*....|....*....|.
gi 6680121  172 PKCLDAFPNLKDFMGRFEGLKKISDYMKSSRFLSKPIFAKM 212
Cdd:cd03209  81 PDCLDAFPNLKDFLERFEALPKISAYMKSDRFIKWPINGWK 121

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 6680121    105 MDTRIQLAMVCYSPDFEKKKPEYLEGLPEKMKLYSEF---LGKQPWFAGNKVTYVDFLVYDVLDQHRIFEPKCL-DAFPN 180
Cdd:pfam00043   2 MDLRMQIALLPYVPPEEKKEPEVDEALEKVARVLSALeevLKGQTYLVGDKLTLADIALAPALLWLYELDPACLrEKFPN 81

                          90
                  ....*....|.
gi 6680121    181 LKDFMGRFEGL 191
Cdd:pfam00043  82 LKAWFERVAAR 92

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

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 6680121    3 MTLGYWDIRGLAHAIRLLLEYTDTSYEDKKYTMGdaPDYDRSQWLSEKFKLGLdfpnLPYLIDGSHKITQSNAILRYLAR 82
Cdd:COG0625   2 MKLYGSPPSPNSRRVRIALEEKGLPYELVPVDLA--KGEQKSPEFLALNPLGK----VPVLVDDGLVLTESLAILEYLAE 75

                        90       100       110       120       130       140       150       160
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 6680121   83 KH---NLCGETEEERIRVDILENQAMDT---RIQLAMVCYSP-DFEKKKPEYLEGLPEKMKLYSEFLGKQPWFAGNKVTY 155
Cdd:COG0625  76 RYpepPLLPADPAARARVRQWLAWADGDlhpALRNLLERLAPeKDPAAIARARAELARLLAVLEARLAGGPYLAGDRFSI 155

                       170       180       190
                ....*....|....*....|....*....|....
gi 6680121  156 VDFLVYDVLDQHRIFEPKcLDAFPNLKDFMGRFE 189
Cdd:COG0625 156 ADIALAPVLRRLDRLGLD-LADYPNLAAWLARLA 188

C-terminal, alpha helical domain of Class Mu Glutathione S-transferases; Glutathione S-transferase (GST) C-terminal domain 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 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. 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        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 6680121   92 EERIRVDILENQAMDTRIQLAMVCYSPDFEKKKPEYLEGLPEKMKLYSEFLGKQPWFAGNKVTYVDFLVYDVLDQHRIFE 171
Cdd:cd03209   1 KERIRVDMLEQQAMDLRMGLIRICYSPDFEKLKPDYLEKLPDKLKLFSEFLGDRPWFAGDKITYVDFLLYEALDQHRIFE 80

                        90       100       110       120
                ....*....|....*....|....*....|....*....|.
gi 6680121  172 PKCLDAFPNLKDFMGRFEGLKKISDYMKSSRFLSKPIFAKM 212
Cdd:cd03209  81 PDCLDAFPNLKDFLERFEALPKISAYMKSDRFIKWPINGWK 121

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        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 6680121    3 MTLGYWDIRGLAHAIRLLLEYTDTSYEDKKYTMGDAPDYDrsqwlsekFKLGLDFPNLPYLIDGSHKITQSNAILRYLAR 82
Cdd:cd03039   1 YKLTYFNIRGRGEPIRLLLADAGVEYEDVRITYEEWPELD--------LKPTLPFGQLPVLEIDGKKLTQSNAILRYLAR 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        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 6680121      3 MTLGYWDIRG--LAHAIRLLLEYTDTSYEDKKYTMGDAPDYDrSQWLSEKFklgldFPNLPYLIDGSHKITQSNAILRYL 80
Cdd:pfam02798   1 MVLTLYGIRGspRAHRIRWLLAEKGVEYEIVPLDFGAGPEKS-PELLKLNP-----LGKVPALEDGGKKLTESRAILEYI 74

                  ..
gi 6680121     81 AR 82
Cdd:pfam02798  75 AR 76

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

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 6680121    105 MDTRIQLAMVCYSPDFEKKKPE----YLEGLPEKMKLYSEFL--GKQPWFAGNKVTYVDFLVYDVLDQHR-IFEPKCLDA 177
Cdd:pfam14497   1 HDLHHPIASSLYYEDEKKKAKRrkefREERLPKFLGYFEKVLnkNGGGYLVGDKLTYADLALFQVLDGLLyPKAPDALDK 80

                          90       100
                  ....*....|....*....|...
gi 6680121    178 FPNLKDFMGRFEGLKKISDYMKS 200
Cdd:pfam14497  81 YPKLKALHERVAARPNIKAYLAS 103

C-terminal, alpha helical domain of Class Pi Glutathione S-transferases; Glutathione S-transferase (GST) C-terminal domain family, Class Pi 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 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. Class Pi GST is a homodimeric eukaryotic protein. The human GSTP1 is mainly found in erythrocytes, kidney, placenta and fetal liver. It is involved in stress responses and in cellular proliferation pathways as an inhibitor of JNK (c-Jun N-terminal kinase). Following oxidative stress, monomeric GSTP1 dissociates from JNK and dimerizes, losing its ability to bind JNK and causing an increase in JNK activity, thereby promoting apoptosis. GSTP1 is expressed in various tumors and is the predominant GST in a wide range of cancer cells. It has been implicated in the development of multidrug-resistant tumors.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 6680121   91 EEERIRVDILENQAMDTRIQLAMVCYsPDFEKKKPEYLEGLPEKMKLYSEFL---GKQPWFAGNKVTYVDFLVYDVLDQH 167
Cdd:cd03210   1 EKEAALIDMVNDGVEDLRLKYVRMIY-QNYEAGKDDYIKDLPEQLKPFEKLLaknNGKGFIVGDKISFADYNLFDLLDIH 79

                        90       100       110       120
                ....*....|....*....|....*....|....*....|.
gi 6680121  168 RIFEPKCLDAFPNLKDFMGRFEGLKKISDYMKSSRFLSKPI 208
Cdd:cd03210  80 LVLAPGCLDAFPLLKAFVERLSARPKLKAYLESDAFKNRPI 120

GST_N family, Class Pi 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. Class Pi GST is a homodimeric eukaryotic protein. The human GSTP1 is mainly found in erythrocytes, kidney, placenta and fetal liver. It is involved in stress responses and in cellular proliferation pathways as an inhibitor of JNK (c-Jun N-terminal kinase). Following oxidative stress, monomeric GSTP1 dissociates from JNK and dimerizes, losing its ability to bind JNK and causing an increase in JNK activity, thereby promoting apoptosis. GSTP1 is expressed in various tumors and is the predominant GST in a wide range of cancer cells. It has been implicated in the development of multidrug-resistant tumours.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 6680121    2 PMTLGYWDIRGLAHAIRLLLEYTDTSYEDKKYTMGDapdydrsqWlSEKFKLGLDFPNLPYLIDGSHKITQSNAILRYLA 81
Cdd:cd03076   1 PYTLTYFPVRGRAEAIRLLLADQGISWEEERVTYEE--------W-QESLKPKMLFGQLPCFKDGDLTLVQSNAILRHLG 71

                ..
gi 6680121   82 RK 83
Cdd:cd03076  72 RK 73

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 6680121  118 PDFEKKKPEYLEGLPEKMKLYSEFLGKQPWFAGNKVTYVDFLVYDVLDQHRIFEPKC--LDAFPNLKDFMGR 187
Cdd:cd00299  28 PKDEAAVEAAREELPALLAALEQLLAGRPYLAGDQFSLADVALAPVLARLEALGPYYdlLDEYPRLKAWYDR 99

C-terminal, alpha helical domain of Class Theta Glutathione S-transferases; Glutathione S-transferase (GST) C-terminal domain family, Class Theta subfamily; composed of eukaryotic class Theta GSTs and bacterial dichloromethane (DCM) dehalogenase. 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 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. Mammalian class Theta GSTs show poor GSH conjugating activity towards the standard substrates, CDNB and ethacrynic acid, differentiating them from other mammalian GSTs. GSTT1-1 shows similar cataytic activity as bacterial DCM dehalogenase, catalyzing the GSH-dependent hydrolytic dehalogenation of dihalomethanes. This is an essential process in methylotrophic bacteria to enable them to use chloromethane and DCM as sole carbon and energy sources. The presence of polymorphisms in human GSTT1-1 and its relationship to the onset of diseases including cancer is the subject of many studies. Human GSTT2-2 exhibits a highly specific sulfatase activity, catalyzing the cleavage of sulfate ions from aralkyl sufate esters, but not from the aryl or alkyl sulfate esters.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 6680121   93 ERIRVD-ILENQAMDTRIQLAMV----------CYSPDFEKKKPEYLEGLPEKMK-LYSEFLGKQPWFAGNKVTYVDFLV 160
Cdd:cd03183   1 KRARVDeYLAWQHTNLRLGCAAYfwqkvllplfGGTPVSPEKVKKAEENLEESLDlLENKFLKDKPFLAGDEISIADLSA 80

                        90       100       110
                ....*....|....*....|....*....|..
gi 6680121  161 YDVLDQH-----RIFEPkcldaFPNLKDFMGR 187
Cdd:cd03183  81 ICEIMQPeaagyDVFEG-----RPKLAAWRKR 107

C-terminal, alpha helical domain of Class Sigma Glutathione S-transferases; Glutathione S-transferase (GST) C-terminal domain family, Class Sigma; 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 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. 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.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 6680121  119 DFEKKKPEYLEG-LPEKMKLYSEFLGKQPWFAGNKVTYVDFLVYDVLDQHRIFEPKCLDAFPNL 181
Cdd:cd10295  30 VKEKMFNEALTGpAPHLLKDLDTYLGGREWLVGKSVTWADFYWDTCSTTLLSFKPDLLKNYPRL 93

GST_N family, Saccharomyces cerevisiae GTT1-like subfamily; composed of predominantly uncharacterized proteins with similarity to the S. cerevisiae GST protein, GTT1, and the Schizosaccharomyces pombe GST-III. 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. GSTs also show GSH peroxidase activity and are involved in the synthesis of prostaglandins and leukotrienes. 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. GTT1, a homodimer, exhibits GST activity with standard substrates and associates with the endoplasmic reticulum. Its expression is induced after diauxic shift and remains high throughout the stationary phase. S. pombe GST-III is implicated in the detoxification of various metals.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 6680121   14 AHAIRLLLEYTDTSYEDKKYTMGD----APDYDRSQwlsekfklgldfPN--LPYLIDGSHKITQSNAILRYLARKH 84
Cdd:cd03046  11 SFRILWLLEELGLPYELVLYDRGPgeqaPPEYLAIN------------PLgkVPVLVDGDLVLTESAAIILYLAEKY 75

GST_N family, Class Phi subfamily; composed of plant-specific class Phi GSTs and related fungal and bacterial proteins. 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 Phi GST subfamily has experience extensive gene duplication. The Arabidopsis and Oryza genomes contain 13 and 16 Phi GSTs, respectively. They are primarily responsible for herbicide detoxification together with class Tau GSTs, showing class specificity in substrate preference. Phi enzymes are highly reactive toward chloroacetanilide and thiocarbamate herbicides. Some Phi GSTs have other functions including transport of flavonoid pigments to the vacuole, shoot regeneration and GSH peroxidase activity.

                        10        20
                ....*....|....*....|....*..
gi 6680121   57 FPNLPYLIDGSHKITQSNAILRYLARK 83
Cdd:cd03053  50 FGQIPALEDGDLKLFESRAITRYLAEK 76