Rossmann-fold NAD(P)(+)-binding proteins; A large family of proteins that share a Rossmann-fold NAD(P)H/NAD(P)(+) binding (NADB) domain. The NADB domain is found in numerous dehydrogenases of metabolic pathways such as glycolysis, and many other redox enzymes. NAD binding involves numerous hydrogen-bonds and van der Waals contacts, in particular H-bonding of residues in a turn between the first strand and the subsequent helix of the Rossmann-fold topology. Characteristically, this turn exhibits a consensus binding pattern similar to GXGXXG, in which the first 2 glycines participate in NAD(P)-binding, and the third facilitates close packing of the helix to the beta-strand. Typically, proteins in this family contain a second domain in addition to the NADB domain, which is responsible for specifically binding a substrate and catalyzing a particular enzymatic reaction.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894  89 AGTVLITGGTGMAGSAVARHVVARHGVRNLVLVSRRGPDAPGAAELVAELAAAGAQVQVVACDAADRAALAKVIADIPVQ 168
Cdd:cd08956   193 DGTVLITGGTGTLGALLARHLVTEHGVRHLLLVSRRGPDAPGAAELVAELAALGAEVTVAACDVADRAALAALLAAVPAD 272

                          90
                  ....*....|....*.
gi 1769863894 169 HPLSGVIHTAGALDDA 184
Cdd:cd08956   273 HPLTAVVHAAGVLDDG 288

beta-ketoacyl reductase (KR) domain of fatty acid synthase (FAS), subgroup 3, complex (x); Ketoreductase, a module of the multidomain polyketide synthase (PKS), has 2 subdomains, each corresponding to a SDR family monomer. The C-terminal subdomain catalyzes the NADPH-dependent reduction of the beta-carbonyl of a polyketide to a hydroxyl group, a step in the biosynthesis of polyketides, such as erythromycin. The N-terminal subdomain, an interdomain linker, is a truncated Rossmann fold which acts to stabilizes the catalytic subdomain. Unlike typical SDRs, the isolated domain does not oligomerize but is composed of 2 subdomains, each resembling an SDR monomer. The active site resembles that of typical SDRs, except that the usual positions of the catalytic Asn and Tyr are swapped, so that the canonical YXXXK motif changes to YXXXN. Modular PKSs are multifunctional structures in which the makeup recapitulates that found in (and may have evolved from) FAS. In some instances, such as porcine FAS, an enoyl reductase (ER) module is inserted between the sub-domains. Fatty acid synthesis occurs via the stepwise elongation of a chain (which is attached to acyl carrier protein, ACP) with 2-carbon units. Eukaryotic systems consists of large, multifunctional synthases (type I) while bacterial, type II systems, use single function proteins. Fungal fatty acid synthesis uses a dodecamer of 6 alpha and 6 beta subunits. In mammalian type FAS cycles, ketoacyl synthase forms acetoacetyl-ACP which is reduced by the NADP-dependent beta-KR, forming beta-hydroxyacyl-ACP, which is in turn dehydrated by dehydratase to a beta-enoyl intermediate, which is reduced by NADP-dependent beta- ER. Polyketide synthesis also proceeds via the addition of 2-carbon units as in fatty acid synthesis. The complex SDR NADP-binding motif, GGXGXXG, is often present, but is not strictly conserved in each instance of the module. This subfamily includes KR domains found in many multidomain PKSs, including six of seven Sorangium cellulosum PKSs (encoded by spiDEFGHIJ) which participate in the synthesis of the polyketide scaffold of the cytotoxic spiroketal polyketide spirangien. These seven PKSs have either a single PKS module (SpiF), two PKR modules (SpiD,-E,-I,-J), or three PKS modules (SpiG,-H). This subfamily includes the second KR domains of SpiE,-G, I, and -J, both KR domains of SpiD, and the third KR domain of SpiH. The single KR domain of SpiF, the first and second KR domains of SpiH, the first KR domains of SpiE,-G,- I, and -J, and the third KR domain of SpiG, belong to a different KR_FAS_SDR subfamily. SDRs are a functionally diverse family of oxidoreductases that have a single domain with a structurally conserved Rossmann fold (alpha/beta folding pattern with a central beta-sheet), an NAD(P)(H)-binding region, and a structurally diverse C-terminal region. Classical SDRs are typically about 250 residues long, while extended SDRs are approximately 350 residues. Sequence identity between different SDR enzymes are typically in the 15-30% range, but the enzymes share the Rossmann fold NAD-binding motif and characteristic NAD-binding and catalytic sequence patterns. These enzymes catalyze a wide range of activities including the metabolism of steroids, cofactors, carbohydrates, lipids, aromatic compounds, and amino acids, and act in redox sensing. Classical SDRs have an TGXXX[AG]XG cofactor binding motif and a YXXXK active site motif, with the Tyr residue of the active site motif serving as a critical catalytic residue (Tyr-151, human prostaglandin dehydrogenase (PGDH) numbering). In addition to the Tyr and Lys, there is often an upstream Ser (Ser-138, PGDH numbering) and/or an Asn (Asn-107, PGDH numbering) contributing to the active site; while substrate binding is in the C-terminal region, which determines specificity. The standard reaction mechanism is a 4-pro-S hydride transfer and proton relay involving the conserved Tyr and Lys, a water molecule stabilized by Asn, and nicotinamide. Extended SDRs have additional elements in the C-terminal region, and typically have a TGXXGXXG cofactor binding motif. Complex (multidomain) SDRs such as ketoreductase domains of fatty acid synthase have a GGXGXXG NAD(P)-binding motif and an altered active site motif (YXXXN). Fungal type KRs have a TGXXXGX(1-2)G NAD(P)-binding motif. Some atypical SDRs have lost catalytic activity and/or have an unusual NAD(P)-binding motif and missing or unusual active site residues. Reactions catalyzed within the SDR family include isomerization, decarboxylation, epimerization, C=N bond reduction, dehydratase activity, dehalogenation, Enoyl-CoA reduction, and carbonyl-alcohol oxidoreduction.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894  89 AGTVLITGGTGMAGSAVARHVVARHGVRNLVLVSRRGPDAPGAAELVAELAAAGAQVQVVACDAADRAALAKVIADIPVQ 168
Cdd:cd08956   193 DGTVLITGGTGTLGALLARHLVTEHGVRHLLLVSRRGPDAPGAAELVAELAALGAEVTVAACDVADRAALAALLAAVPAD 272

                          90
                  ....*....|....*.
gi 1769863894 169 HPLSGVIHTAGALDDA 184
Cdd:cd08956   273 HPLTAVVHAAGVLDDG 288

Enoylreductase; Enoylreductase in Polyketide synthases.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894    1 MGKTDIRDPGVIA--QQYPGVRYRAFDL--FEPGPDRIAQILAELATLFGDGVLRPLPVTTFDVRCAPAALRYLSQARHT 76
Cdd:smart00829 203 IGKRDIRDNSQLAmaPFRPNVSYHAVDLdaLEEGPDRIRELLAEVLELFAEGVLRPLPVTVFPISDAEDAFRYMQQGKHI 282

                   ....
gi 1769863894   77 GKVV 80
Cdd:smart00829 283 GKVV 286

enoyl reductase of polyketide synthase; Putative enoyl reductase of polyketide synthase. Polyketide synthases produce polyketides in step by step mechanism that is similar to fatty acid synthesis. Enoyl reductase reduces a double to single bond. Erythromycin is one example of a polyketide generated by 3 complex enzymes (megasynthases). 2-enoyl thioester reductase (ETR) catalyzes the NADPH-dependent dependent conversion of trans-2-enoyl acyl carrier protein/coenzyme A (ACP/CoA) to acyl-(ACP/CoA) in fatty acid synthesis. 2-enoyl thioester reductase activity has been linked in Candida tropicalis as essential in maintaining mitiochondrial respiratory function. This ETR family is a part of the medium chain dehydrogenase/reductase family, but lack the zinc coordination sites characteristic of the alcohol dehydrogenases in this family. NAD(P)(H)-dependent oxidoreductases are the major enzymes in the interconversion of alcohols and aldehydes or ketones. Alcohol dehydrogenase in the liver converts ethanol and NAD+ to acetaldehyde and NADH, while in yeast and some other microorganisms ADH catalyzes the conversion acetaldehyde to ethanol in alcoholic fermentation. ADH is a member of the medium chain alcohol dehydrogenase family (MDR), which has a NAD(P)(H)-binding domain in a Rossmann fold of a beta-alpha form. The NAD(H)-binding region is comprised of 2 structurally similar halves, each of which contacts a mononucleotide. The N-terminal catalytic domain has a distant homology to GroES. These proteins typically form dimers (typically higher plants, mammals) or tetramers (yeast, bacteria), and have 2 tightly bound zinc atoms per subunit, a catalytic zinc at the active site, and a structural zinc in a lobe of the catalytic domain. NAD(H) binding occurs in the cleft between the catalytic and coenzyme-binding domains, at the active site, and coenzyme binding induces a conformational closing of this cleft. Coenzyme binding typically precedes and contributes to substrate binding.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894   1 MGKTDIRDPGVIAQQ--YPGVRYRAFDL---FEPGPDRIAQILAELATLFGDGVLRPLPVTTFDVRCAPAALRYLSQARH 75
Cdd:cd05195   208 IGKRDILSNSKLGMRpfLRNVSFSSVDLdqlARERPELLRELLREVLELLEAGVLKPLPPTVVPSASEIDAFRLMQSGKH 287

                  ....*.
gi 1769863894  76 TGKVVM 81
Cdd:cd05195   288 IGKVVL 293

Zinc-binding dehydrogenase;

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1769863894   2 GKTDIRDPGVIAQQYPGVRYRAFDLFePGPDRIAQILAELATLFGDGVLRPLPVTTFDVRCAPAALRYLSQARHTGKVV 80
Cdd:pfam13602  53 GPPLSAGLLLPARKRGGRGVKYLFLF-VRPNLGADILQELADLIEEGKLRPVIDRVFPLEEAAEAHRYLESGRARGKIV 130

3-oxoacyl-ACP reductase FabG;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894  91 TVLITGGTGMAGSAVARhVVARHGVRnlVLVSRRGPDApgAAELVAELAAAGAQVQVVACDAADRAALAKVIADIPVQH- 169
Cdd:PRK05653    7 TALVTGASRGIGRAIAL-RLAADGAK--VVIYDSNEEA--AEALAAELRAAGGEARVLVFDVSDEAAVRALIEAAVEAFg 81

                          90
                  ....*....|....*
gi 1769863894 170 PLSGVIHTAGALDDA 184
Cdd:PRK05653   82 ALDILVNNAGITRDA 96

beta-ketoacyl reductase (KR) domain of fatty acid synthase (FAS), subgroup 3, complex (x); Ketoreductase, a module of the multidomain polyketide synthase (PKS), has 2 subdomains, each corresponding to a SDR family monomer. The C-terminal subdomain catalyzes the NADPH-dependent reduction of the beta-carbonyl of a polyketide to a hydroxyl group, a step in the biosynthesis of polyketides, such as erythromycin. The N-terminal subdomain, an interdomain linker, is a truncated Rossmann fold which acts to stabilizes the catalytic subdomain. Unlike typical SDRs, the isolated domain does not oligomerize but is composed of 2 subdomains, each resembling an SDR monomer. The active site resembles that of typical SDRs, except that the usual positions of the catalytic Asn and Tyr are swapped, so that the canonical YXXXK motif changes to YXXXN. Modular PKSs are multifunctional structures in which the makeup recapitulates that found in (and may have evolved from) FAS. In some instances, such as porcine FAS, an enoyl reductase (ER) module is inserted between the sub-domains. Fatty acid synthesis occurs via the stepwise elongation of a chain (which is attached to acyl carrier protein, ACP) with 2-carbon units. Eukaryotic systems consists of large, multifunctional synthases (type I) while bacterial, type II systems, use single function proteins. Fungal fatty acid synthesis uses a dodecamer of 6 alpha and 6 beta subunits. In mammalian type FAS cycles, ketoacyl synthase forms acetoacetyl-ACP which is reduced by the NADP-dependent beta-KR, forming beta-hydroxyacyl-ACP, which is in turn dehydrated by dehydratase to a beta-enoyl intermediate, which is reduced by NADP-dependent beta- ER. Polyketide synthesis also proceeds via the addition of 2-carbon units as in fatty acid synthesis. The complex SDR NADP-binding motif, GGXGXXG, is often present, but is not strictly conserved in each instance of the module. This subfamily includes KR domains found in many multidomain PKSs, including six of seven Sorangium cellulosum PKSs (encoded by spiDEFGHIJ) which participate in the synthesis of the polyketide scaffold of the cytotoxic spiroketal polyketide spirangien. These seven PKSs have either a single PKS module (SpiF), two PKR modules (SpiD,-E,-I,-J), or three PKS modules (SpiG,-H). This subfamily includes the second KR domains of SpiE,-G, I, and -J, both KR domains of SpiD, and the third KR domain of SpiH. The single KR domain of SpiF, the first and second KR domains of SpiH, the first KR domains of SpiE,-G,- I, and -J, and the third KR domain of SpiG, belong to a different KR_FAS_SDR subfamily. SDRs are a functionally diverse family of oxidoreductases that have a single domain with a structurally conserved Rossmann fold (alpha/beta folding pattern with a central beta-sheet), an NAD(P)(H)-binding region, and a structurally diverse C-terminal region. Classical SDRs are typically about 250 residues long, while extended SDRs are approximately 350 residues. Sequence identity between different SDR enzymes are typically in the 15-30% range, but the enzymes share the Rossmann fold NAD-binding motif and characteristic NAD-binding and catalytic sequence patterns. These enzymes catalyze a wide range of activities including the metabolism of steroids, cofactors, carbohydrates, lipids, aromatic compounds, and amino acids, and act in redox sensing. Classical SDRs have an TGXXX[AG]XG cofactor binding motif and a YXXXK active site motif, with the Tyr residue of the active site motif serving as a critical catalytic residue (Tyr-151, human prostaglandin dehydrogenase (PGDH) numbering). In addition to the Tyr and Lys, there is often an upstream Ser (Ser-138, PGDH numbering) and/or an Asn (Asn-107, PGDH numbering) contributing to the active site; while substrate binding is in the C-terminal region, which determines specificity. The standard reaction mechanism is a 4-pro-S hydride transfer and proton relay involving the conserved Tyr and Lys, a water molecule stabilized by Asn, and nicotinamide. Extended SDRs have additional elements in the C-terminal region, and typically have a TGXXGXXG cofactor binding motif. Complex (multidomain) SDRs such as ketoreductase domains of fatty acid synthase have a GGXGXXG NAD(P)-binding motif and an altered active site motif (YXXXN). Fungal type KRs have a TGXXXGX(1-2)G NAD(P)-binding motif. Some atypical SDRs have lost catalytic activity and/or have an unusual NAD(P)-binding motif and missing or unusual active site residues. Reactions catalyzed within the SDR family include isomerization, decarboxylation, epimerization, C=N bond reduction, dehydratase activity, dehalogenation, Enoyl-CoA reduction, and carbonyl-alcohol oxidoreduction.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894  89 AGTVLITGGTGMAGSAVARHVVARHGVRNLVLVSRRGPDAPGAAELVAELAAAGAQVQVVACDAADRAALAKVIADIPVQ 168
Cdd:cd08956   193 DGTVLITGGTGTLGALLARHLVTEHGVRHLLLVSRRGPDAPGAAELVAELAALGAEVTVAACDVADRAALAALLAAVPAD 272

                          90
                  ....*....|....*.
gi 1769863894 169 HPLSGVIHTAGALDDA 184
Cdd:cd08956   273 HPLTAVVHAAGVLDDG 288

ketoreductase (KR), subgroup 1, complex (x) SDRs; Ketoreductase, a module of the multidomain polyketide synthase (PKS), has 2 subdomains, each corresponding to a SDR family monomer. The C-terminal subdomain catalyzes the NADPH-dependent reduction of the beta-carbonyl of a polyketide to a hydroxyl group, a step in the biosynthesis of polyketides, such as erythromycin. The N-terminal subdomain, an interdomain linker, is a truncated Rossmann fold which acts to stabilizes the catalytic subdomain. Unlike typical SDRs, the isolated domain does not oligomerize but is composed of 2 subdomains, each resembling an SDR monomer. The active site resembles that of typical SDRs, except that the usual positions of the catalytic Asn and Tyr are swapped, so that the canonical YXXXK motif changes to YXXXN. Modular PKSs are multifunctional structures in which the makeup recapitulates that found in (and may have evolved from) FAS. Polyketide synthesis also proceeds via the addition of 2-carbon units as in fatty acid synthesis. The complex SDR NADP-binding motif, GGXGXXG, is often present, but is not strictly conserved in each instance of the module. This subfamily includes KR domains found in many multidomain PKSs, including six of seven Sorangium cellulosum PKSs (encoded by spiDEFGHIJ) which participate in the synthesis of the polyketide scaffold of the cytotoxic spiroketal polyketide spirangien. These seven PKSs have either a single PKS module (SpiF), two PKR modules (SpiD,-E,-I,-J), or three PKS modules (SpiG,-H). This subfamily includes the single KR domain of SpiF, the first KR domains of SpiE,-G,H,-I,and #J, the third KR domain of SpiG, and the second KR domain of SpiH. The second KR domains of SpiE,-G, I, and #J, and the KR domains of SpiD, belong to a different KR_FAS_SDR subfamily. SDRs are a functionally diverse family of oxidoreductases that have a single domain with a structurally conserved Rossmann fold (alpha/beta folding pattern with a central beta-sheet), an NAD(P)(H)-binding region, and a structurally diverse C-terminal region. Classical SDRs are typically about 250 residues long, while extended SDRs are approximately 350 residues. Sequence identity between different SDR enzymes are typically in the 15-30% range, but the enzymes share the Rossmann fold NAD-binding motif and characteristic NAD-binding and catalytic sequence patterns. These enzymes catalyze a wide range of activities including the metabolism of steroids, cofactors, carbohydrates, lipids, aromatic compounds, and amino acids, and act in redox sensing. Classical SDRs have an TGXXX[AG]XG cofactor binding motif and a YXXXK active site motif, with the Tyr residue of the active site motif serving as a critical catalytic residue (Tyr-151, human prostaglandin dehydrogenase (PGDH) numbering). In addition to the Tyr and Lys, there is often an upstream Ser (Ser-138, PGDH numbering) and/or an Asn (Asn-107, PGDH numbering) contributing to the active site; while substrate binding is in the C-terminal region, which determines specificity. The standard reaction mechanism is a 4-pro-S hydride transfer and proton relay involving the conserved Tyr and Lys, a water molecule stabilized by Asn, and nicotinamide. Extended SDRs have additional elements in the C-terminal region, and typically have a TGXXGXXG cofactor binding motif. Complex (multidomain) SDRs such as ketoreductase domains of fatty acid synthase have a GGXGXXG NAD(P)-binding motif and an altered active site motif (YXXXN). Fungal type KRs have a TGXXXGX(1-2)G NAD(P)-binding motif. Some atypical SDRs have lost catalytic activity and/or have an unusual NAD(P)-binding motif and missing or unusual active site residues. Reactions catalyzed within the SDR family include isomerization, decarboxylation, epimerization, C=N bond reduction, dehydratase activity, dehalogenation, Enoyl-CoA reduction, and carbonyl-alcohol oxidoreduction.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894  89 AGTVLITGGTGMAGSAVARHVvARHGVRNLVLVSRRGPDAPGAAELVAELAAAGAQVQVVACDAADRAALAKVIADIPVQ 168
Cdd:cd08952   230 RGTVLVTGGTGALGAHVARWL-ARRGAEHLVLTSRRGPDAPGAAELVAELTALGARVTVAACDVADRDALAALLAALPAG 308

                          90
                  ....*....|....*.
gi 1769863894 169 HPLSGVIHTAGALDDA 184
Cdd:cd08952   309 HPLTAVVHAAGVLDDG 324

KR domain; This enzymatic domain is part of bacterial polyketide synthases and catalyzes the first step in the reductive modification of the beta-carbonyl centres in the growing polyketide chain. It uses NADPH to reduce the keto group to a hydroxy group.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894  90 GTVLITGGTGMAGSAVARHVvARHGVRNLVLVSRRGPDAPGAAELVAELAAAGAQVQVVACDAADRAALAKVIADIPVQ- 168
Cdd:pfam08659   1 GTYLITGGLGGLGRELARWL-AERGARHLVLLSRSAAPRPDAQALIAELEARGVEVVVVACDVSDPDAVAALLAEIKAEg 79

                          90
                  ....*....|....*.
gi 1769863894 169 HPLSGVIHTAGALDDA 184
Cdd:pfam08659  80 PPIRGVIHAAGVLRDA 95

beta-ketoacyl reductase (KR) domain of fatty acid synthase (FAS), subgroup 2, complex (x); Ketoreductase, a module of the multidomain polyketide synthase, has 2 subdomains, each corresponding to a short-chain dehydrogenases/reductase (SDR) family monomer. The C-terminal subdomain catalyzes the NADPH-dependent reduction of the beta-carbonyl of a polyketide to a hydroxyl group, a step in the biosynthesis of polyketides, such as erythromycin. The N-terminal subdomain, an interdomain linker, is a truncated Rossmann fold which acts to stabilizes the catalytic subdomain. Unlike typical SDRs, the isolated domain does not oligomerizes but is composed of 2 subdomains, each resembling an SDR monomer. In some instances, as in porcine FAS, an enoyl reductase (a Rossman fold NAD binding domain of the MDR family) module is inserted between the sub-domains. The active site resembles that of typical SDRs, except that the usual positions of the catalytic asparagine and tyrosine are swapped, so that the canonical YXXXK motif changes to YXXXN. Modular polyketide synthases are multifunctional structures in which the makeup recapitulates that found in (and may have evolved from) fatty acid synthase. In some instances, such as porcine FAS , an enoyl reductase module is inserted between the sub-domains. Fatty acid synthesis occurs via the stepwise elongation of a chain (which is attached to acyl carrier protein, ACP) with 2-carbon units. Eukaryotic systems consists of large, multifunctional synthases (type I) while bacterial, type II systems, use single function proteins. Fungal fatty acid synthesis uses dodecamer of 6 alpha and 6 beta subunits. In mammalian type FAS cycles, ketoacyl synthase forms acetoacetyl-ACP which is reduced by the NADP-dependent beta-ketoacyl reductase (KR), forming beta-hydroxyacyl-ACP, which is in turn dehydrated by dehydratase to a beta-enoyl intermediate, which is reduced by NADP-dependent beta-enoyl reductase (ER). Polyketide syntheses also proceeds via the addition of 2-carbon units as in fatty acid synthesis. The complex SDR NADP binding motif, GGXGXXG, is often present, but is not strictly conserved in each instance of the module. This subfamily includes the KR domain of the Lyngbya majuscule Jam J, -K, and #L which are encoded on the jam gene cluster and are involved in the synthesis of the Jamaicamides (neurotoxins); Lyngbya majuscule Jam P belongs to a different KR_FAS_SDR_x subfamily. SDRs are a functionally diverse family of oxidoreductases that have a single domain with a structurally conserved Rossmann fold (alpha/beta folding pattern with a central beta-sheet), an NAD(P)(H)-binding region, and a structurally diverse C-terminal region. Classical SDRs are typically about 250 residues long, while extended SDRs are approximately 350 residues. Sequence identity between different SDR enzymes are typically in the 15-30% range, but the enzymes share the Rossmann fold NAD-binding motif and characteristic NAD-binding and catalytic sequence patterns. These enzymes catalyze a wide range of activities including the metabolism of steroids, cofactors, carbohydrates, lipids, aromatic compounds, and amino acids, and act in redox sensing. Classical SDRs have an TGXXX[AG]XG cofactor binding motif and a YXXXK active site motif, with the Tyr residue of the active site motif serving as a critical catalytic residue (Tyr-151, human prostaglandin dehydrogenase (PGDH) numbering). In addition to the Tyr and Lys, there is often an upstream Ser (Ser-138, PGDH numbering) and/or an Asn (Asn-107, PGDH numbering) contributing to the active site; while substrate binding is in the C-terminal region, which determines specificity. The standard reaction mechanism is a 4-pro-S hydride transfer and proton relay involving the conserved Tyr and Lys, a water molecule stabilized by Asn, and nicotinamide. Extended SDRs have additional elements in the C-terminal region, and typically have a TGXXGXXG cofactor binding motif. Complex (multidomain) SDRs such as ketoreductase domains of fatty acid synthase have a GGXGXXG NAD(P)-binding motif and an altered active site motif (YXXXN). Fungal type KRs have a TGXXXGX(1-2)G NAD(P)-binding motif. Some atypical SDRs have lost catalytic activity and/or have an unusual NAD(P)-binding motif and missing or unusual active site residues. Reactions catalyzed within the SDR family include isomerization, decarboxylation, epimerization, C=N bond reduction, dehydratase activity, dehalogenation, Enoyl-CoA reduction, and carbonyl-alcohol oxidoreduction.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894  11 VIAQQYPGVRYRAFDL--FEPGPDRIAQILAEL-ATLFGDGVlrplpvttfdvrcapaALRylSQARHTGKVVMLMPGSW 87
Cdd:cd08955    85 VIALEHPELRCGLVDLdpEATAAEEAEALLAELlAADAEDQV----------------ALR--GGARYVARLVRAPARPL 146

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894  88 AA-GTVLITGGTGMAGSAVARHVVARhGVRNLVLVSRRGPDAPgAAELVAELAAAGAQVQVVACDAADRAALAKVIADI- 165
Cdd:cd08955   147 RPdATYLITGGLGGLGLLVAEWLVER-GARHLVLTGRRAPSAA-ARQAIAALEEAGAEVVVLAADVSDRDALAAALAQIr 224

                         170
                  ....*....|....*....
gi 1769863894 166 PVQHPLSGVIHTAGALDDA 184
Cdd:cd08955   225 ASLPPLRGVIHAAGVLDDG 243

enoyl reductase of polyketide synthase; Putative enoyl reductase of polyketide synthase. Polyketide synthases produce polyketides in step by step mechanism that is similar to fatty acid synthesis. Enoyl reductase reduces a double to single bond. Erythromycin is one example of a polyketide generated by 3 complex enzymes (megasynthases). 2-enoyl thioester reductase (ETR) catalyzes the NADPH-dependent dependent conversion of trans-2-enoyl acyl carrier protein/coenzyme A (ACP/CoA) to acyl-(ACP/CoA) in fatty acid synthesis. 2-enoyl thioester reductase activity has been linked in Candida tropicalis as essential in maintaining mitiochondrial respiratory function. This ETR family is a part of the medium chain dehydrogenase/reductase family, but lack the zinc coordination sites characteristic of the alcohol dehydrogenases in this family. NAD(P)(H)-dependent oxidoreductases are the major enzymes in the interconversion of alcohols and aldehydes or ketones. Alcohol dehydrogenase in the liver converts ethanol and NAD+ to acetaldehyde and NADH, while in yeast and some other microorganisms ADH catalyzes the conversion acetaldehyde to ethanol in alcoholic fermentation. ADH is a member of the medium chain alcohol dehydrogenase family (MDR), which has a NAD(P)(H)-binding domain in a Rossmann fold of a beta-alpha form. The NAD(H)-binding region is comprised of 2 structurally similar halves, each of which contacts a mononucleotide. The N-terminal catalytic domain has a distant homology to GroES. These proteins typically form dimers (typically higher plants, mammals) or tetramers (yeast, bacteria), and have 2 tightly bound zinc atoms per subunit, a catalytic zinc at the active site, and a structural zinc in a lobe of the catalytic domain. NAD(H) binding occurs in the cleft between the catalytic and coenzyme-binding domains, at the active site, and coenzyme binding induces a conformational closing of this cleft. Coenzyme binding typically precedes and contributes to substrate binding.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894   1 MGKTDIRDPGVIAQQ--YPGVRYRAFDL---FEPGPDRIAQILAELATLFGDGVLRPLPVTTFDVRCAPAALRYLSQARH 75
Cdd:cd05195   208 IGKRDILSNSKLGMRpfLRNVSFSSVDLdqlARERPELLRELLREVLELLEAGVLKPLPPTVVPSASEIDAFRLMQSGKH 287

                  ....*.
gi 1769863894  76 TGKVVM 81
Cdd:cd05195   288 IGKVVL 293

Zinc-binding dehydrogenase;

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1769863894   2 GKTDIRDPGVIAQQYPGVRYRAFDLFePGPDRIAQILAELATLFGDGVLRPLPVTTFDVRCAPAALRYLSQARHTGKVV 80
Cdd:pfam13602  53 GPPLSAGLLLPARKRGGRGVKYLFLF-VRPNLGADILQELADLIEEGKLRPVIDRVFPLEEAAEAHRYLESGRARGKIV 130

3-oxoacyl-ACP reductase FabG;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894  91 TVLITGGTGMAGSAVARhVVARHGVRnlVLVSRRGPDApgAAELVAELAAAGAQVQVVACDAADRAALAKVIADIPVQH- 169
Cdd:PRK05653    7 TALVTGASRGIGRAIAL-RLAADGAK--VVIYDSNEEA--AEALAAELRAAGGEARVLVFDVSDEAAVRALIEAAVEAFg 81

                          90
                  ....*....|....*
gi 1769863894 170 PLSGVIHTAGALDDA 184
Cdd:PRK05653   82 ALDILVNNAGITRDA 96

Quinone oxidoreductase (QOR); QOR catalyzes the conversion of a quinone + NAD(P)H to a hydroquinone + NAD(P)+. Quinones are cyclic diones derived from aromatic compounds. Membrane bound QOR acts in the respiratory chains of bacteria and mitochondria, while soluble QOR acts to protect from toxic quinones (e.g. DT-diaphorase) or as a soluble eye-lens protein in some vertebrates (e.g. zeta-crystalin). QOR reduces quinones through a semi-quinone intermediate via a NAD(P)H-dependent single electron transfer. QOR is a member of the medium chain dehydrogenase/reductase family, but lacks the zinc-binding sites of the prototypical alcohol dehydrogenases of this group. NAD(P)(H)-dependent oxidoreductases are the major enzymes in the interconversion of alcohols and aldehydes, or ketones. Alcohol dehydrogenase in the liver converts ethanol and NAD+ to acetaldehyde and NADH, while in yeast and some other microorganisms ADH catalyzes the conversion acetaldehyde to ethanol in alcoholic fermentation. ADH is a member of the medium chain alcohol dehydrogenase family (MDR), which has a NAD(P)(H)-binding domain in a Rossmann fold of a beta-alpha form. The NAD(H)-binding region is comprised of 2 structurally similar halves, each of which contacts a mononucleotide. A GxGxxG motif after the first mononucleotide contact half allows the close contact of the coenzyme with the ADH backbone. The N-terminal catalytic domain has a distant homology to GroES. These proteins typically form dimers (typically higher plants, mammals) or tetramers (yeast, bacteria), and have 2 tightly bound zinc atoms per subunit, a catalytic zinc at the active site, and a structural zinc in a lobe of the catalytic domain. NAD(H)-binding occurs in the cleft between the catalytic and coenzyme-binding domains at the active site, and coenzyme binding induces a conformational closing of this cleft. Coenzyme binding typically precedes and contributes to substrate binding. In human ADH catalysis, the zinc ion helps coordinate the alcohol, followed by deprotonation of a histidine, the ribose of NAD, a serine, then the alcohol, which allows the transfer of a hydride to NAD+, creating NADH and a zinc-bound aldehyde or ketone. In yeast and some bacteria, the active site zinc binds an aldehyde, polarizing it, and leading to the reverse reaction.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1769863894  18 GVRYRAFDLFEPgpDRIAQILAELATLFGDGVLRPLPVTTFDVRCAPAALRYLSQARHTGKVV 80
Cdd:cd08241   261 GVYWGAYARREP--ELLRANLAELFDLLAEGKIRPHVSAVFPLEQAAEALRALADRKATGKVV 321

sepiapterin reductase (SPR)-like, classical (c) SDRs; Human SPR, a member of the SDR family, catalyzes the NADP-dependent reduction of sepiaptern to 7,8-dihydrobiopterin (BH2). In addition to SPRs, this subgroup also contains Bacillus cereus yueD, a benzil reductase, which catalyzes the stereospecific reduction of benzil to (S)-benzoin. SDRs are a functionally diverse family of oxidoreductases that have a single domain with a structurally conserved Rossmann fold (alpha/beta folding pattern with a central beta-sheet), an NAD(P)(H)-binding region, and a structurally diverse C-terminal region. Classical SDRs are typically about 250 residues long, while extended SDRs are approximately 350 residues. Sequence identity between different SDR enzymes are typically in the 15-30% range, but the enzymes share the Rossmann fold NAD-binding motif and characteristic NAD-binding and catalytic sequence patterns. These enzymes catalyze a wide range of activities including the metabolism of steroids, cofactors, carbohydrates, lipids, aromatic compounds, and amino acids, and act in redox sensing. Classical SDRs have an TGXXX[AG]XG cofactor binding motif and a YXXXK active site motif, with the Tyr residue of the active site motif serving as a critical catalytic residue (Tyr-151, human 15-hydroxyprostaglandin dehydrogenase (15-PGDH) numbering). In addition to the Tyr and Lys, there is often an upstream Ser (Ser-138, 15-PGDH numbering) and/or an Asn (Asn-107, 15-PGDH numbering) contributing to the active site; while substrate binding is in the C-terminal region, which determines specificity. The standard reaction mechanism is a 4-pro-S hydride transfer and proton relay involving the conserved Tyr and Lys, a water molecule stabilized by Asn, and nicotinamide. Extended SDRs have additional elements in the C-terminal region, and typically have a TGXXGXXG cofactor binding motif. Complex (multidomain) SDRs such as ketoreductase domains of fatty acid synthase have a GGXGXXG NAD(P)-binding motif and an altered active site motif (YXXXN). Fungal type ketoacyl reductases have a TGXXXGX(1-2)G NAD(P)-binding motif. Some atypical SDRs have lost catalytic activity and/or have an unusual NAD(P)-binding motif and missing or unusual active site residues. Reactions catalyzed within the SDR family include isomerization, decarboxylation, epimerization, C=N bond reduction, dehydratase activity, dehalogenation, Enoyl-CoA reduction, and carbonyl-alcohol oxidoreduction.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894  91 TVLITGGTGMAGSAVARHVVARHGVRNLVLVSRRGPDApgaaELVAELAAAGAQVQVVACDAADRAALAKVIADIP-VQH 169
Cdd:cd05367     1 VIILTGASRGIGRALAEELLKRGSPSVVVLLARSEEPL----QELKEELRPGLRVTTVKADLSDAAGVEQLLEAIRkLDG 76

                          90
                  ....*....|....
gi 1769863894 170 PLSGVIHTAGALDD 183
Cdd:cd05367    77 ERDLLINNAGSLGP 90

classical (c) SDRs; SDRs are a functionally diverse family of oxidoreductases that have a single domain with a structurally conserved Rossmann fold (alpha/beta folding pattern with a central beta-sheet), an NAD(P)(H)-binding region, and a structurally diverse C-terminal region. Classical SDRs are typically about 250 residues long, while extended SDRs are approximately 350 residues. Sequence identity between different SDR enzymes are typically in the 15-30% range, but the enzymes share the Rossmann fold NAD-binding motif and characteristic NAD-binding and catalytic sequence patterns. These enzymes catalyze a wide range of activities including the metabolism of steroids, cofactors, carbohydrates, lipids, aromatic compounds, and amino acids, and act in redox sensing. Classical SDRs have an TGXXX[AG]XG cofactor binding motif and a YXXXK active site motif, with the Tyr residue of the active site motif serving as a critical catalytic residue (Tyr-151, human prostaglandin dehydrogenase (PGDH) numbering). In addition to the Tyr and Lys, there is often an upstream Ser (Ser-138, PGDH numbering) and/or an Asn (Asn-107, PGDH numbering) contributing to the active site; while substrate binding is in the C-terminal region, which determines specificity. The standard reaction mechanism is a 4-pro-S hydride transfer and proton relay involving the conserved Tyr and Lys, a water molecule stabilized by Asn, and nicotinamide. Extended SDRs have additional elements in the C-terminal region, and typically have a TGXXGXXG cofactor binding motif. Complex (multidomain) SDRs such as ketoreductase domains of fatty acid synthase have a GGXGXXG NAD(P)-binding motif and an altered active site motif (YXXXN). Fungal type ketoacyl reductases have a TGXXXGX(1-2)G NAD(P)-binding motif. Some atypical SDRs have lost catalytic activity and/or have an unusual NAD(P)-binding motif and missing or unusual active site residues. Reactions catalyzed within the SDR family include isomerization, decarboxylation, epimerization, C=N bond reduction, dehydratase activity, dehalogenation, Enoyl-CoA reduction, and carbonyl-alcohol oxidoreduction.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894  92 VLITGGTGMAGSAVARHvVARHGVRnLVLVSRRGPDApgaaELVAELAAAGAQVQVVACDAADRAALAKVIADIPVQH-P 170
Cdd:cd05233     1 ALVTGASSGIGRAIARR-LAREGAK-VVLADRNEEAL----AELAAIEALGGNAVAVQADVSDEEDVEALVEEALEEFgR 74

                  ....*....
gi 1769863894 171 LSGVIHTAG 179
Cdd:cd05233    75 LDILVNNAG 83

3-ketoacyl-(acyl-carrier-protein) reductase; Provisional

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894  91 TVLITGGTGMAGSAVARHVvARHGVRnlVLVSRRGpDAPGAAELVAELAAAGAQVQVVACDAADRAALAKVIADIPVQH- 169
Cdd:PRK12825    8 VALVTGAARGLGRAIALRL-ARAGAD--VVVHYRS-DEEAAEELVEAVEALGRRAQAVQADVTDKAALEAAVAAAVERFg 83

                          90
                  ....*....|....*
gi 1769863894 170 PLSGVIHTAGALDDA 184
Cdd:PRK12825   84 RIDILVNNAGIFEDK 98

beta-ketoacyl reductase (KR) domain of fatty acid synthase (FAS), subgroup 1, complex (x) SDRs; NADP-dependent KR domain of the multidomain type I FAS, a complex SDR family. This subfamily also includes proteins identified as polyketide synthase (PKS), a protein with related modular protein architecture and similar function. It includes the KR domains of mammalian and chicken FAS, and Dictyostelium discoideum putative polyketide synthases (PKSs). These KR domains contain two subdomains, each of which is related to SDR Rossmann fold domains. However, while the C-terminal subdomain has an active site similar to the other SDRs and a NADP-binding capability, the N-terminal SDR-like subdomain is truncated and lacks these functions, serving a supportive structural role. In some instances, such as porcine FAS, an enoyl reductase (a Rossman fold NAD-binding domain of the medium-chain dehydrogenase/reductase, MDR family) module is inserted between the sub-domains. Fatty acid synthesis occurs via the stepwise elongation of a chain (which is attached to acyl carrier protein, ACP) with 2-carbon units. Eukaryotic systems consists of large, multifunctional synthases (type I) while bacterial, type II systems, use single function proteins. Fungal fatty acid synthesis uses a dodecamer of 6 alpha and 6 beta subunits. In mammalian type FAS cycles, ketoacyl synthase forms acetoacetyl-ACP which is reduced by the NADP-dependent beta-ketoacyl reductase (KR), forming beta-hydroxyacyl-ACP, which is in turn dehydrated by dehydratase to a beta-enoyl intermediate, which is reduced by NADP-dependent beta-enoyl reductase (ER); this KR and ER are members of the SDR family. This KR subfamily has an active site tetrad with a similar 3D orientation compared to archetypical SDRs, but the active site Lys and Asn residue positions are swapped. The characteristic NADP-binding is typical of the multidomain complex SDRs, with a GGXGXXG NADP binding motif. SDRs are a functionally diverse family of oxidoreductases that have a single domain with a structurally conserved Rossmann fold (alpha/beta folding pattern with a central beta-sheet), an NAD(P)(H)-binding region, and a structurally diverse C-terminal region. Classical SDRs are typically about 250 residues long, while extended SDRs are approximately 350 residues. Sequence identity between different SDR enzymes are typically in the 15-30% range, but the enzymes share the Rossmann fold NAD-binding motif and characteristic NAD-binding and catalytic sequence patterns. These enzymes catalyze a wide range of activities including the metabolism of steroids, cofactors, carbohydrates, lipids, aromatic compounds, and amino acids, and act in redox sensing. Classical SDRs have an TGXXX[AG]XG cofactor binding motif and a YXXXK active site motif, with the Tyr residue of the active site motif serving as a critical catalytic residue (Tyr-151, human prostaglandin dehydrogenase (PGDH) numbering). In addition to the Tyr and Lys, there is often an upstream Ser (Ser-138, PGDH numbering) and/or an Asn (Asn-107, PGDH numbering) contributing to the active site; while substrate binding is in the C-terminal region, which determines specificity. The standard reaction mechanism is a 4-pro-S hydride transfer and proton relay involving the conserved Tyr and Lys, a water molecule stabilized by Asn, and nicotinamide. Extended SDRs have additional elements in the C-terminal region, and typically have a TGXXGXXG cofactor binding motif. Complex (multidomain) SDRs such as ketoreductase domains of fatty acid synthase have a GGXGXXG NAD(P)-binding motif and an altered active site motif (YXXXN). Fungal type KRs have a TGXXXGX(1-2)G NAD(P)-binding motif. Some atypical SDRs have lost catalytic activity and/or have an unusual NAD(P)-binding motif and missing or unusual active site residues. Reactions catalyzed within the SDR family include isomerization, decarboxylation, epimerization, C=N bond reduction, dehydratase activity, dehalogenation, Enoyl-CoA reduction, and carbonyl-alcohol oxidoreduction.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894  91 TVLITGGTGMAGSAVARHVVARHGVRNLVLVSRRGPDAPGAAELV--AELAAAGAQVQVvacDAADRAALAKVIADIPVQ 168
Cdd:cd08954   220 SYLITGGSGGLGLEILKWLVKRGAVENIIILSRSGMKWELELLIRewKSQNIKFHFVSV---DVSDVSSLEKAINLILNA 296

                          90
                  ....*....|....*....
gi 1769863894 169 H---PLSGVIHTAGALDDA 184
Cdd:cd08954   297 PkigPIGGIFHLAFVLIDK 315

Uncharacterized conserved protein YbjT, contains NAD(P)-binding and DUF2867 domains [General function prediction only];

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1769863894  91 TVLITGGTGMAGSAVARHVVAR-HGVRnlvLVSRRGPDAPGAAElvaelaaagAQVQVVACDAADRAALAKVIADI 165
Cdd:COG0702     1 KILVTGATGFIGRRVVRALLARgHPVR---ALVRDPEKAAALAA---------AGVEVVQGDLDDPESLAAALAGV 64

SDR family oxidoreductase;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894  91 TVLITGGTGMAGSAVARHVvARHGVRnLVLVSRRGPDAPGAAELVAELaaaGAQVQVVACDAADRAALAKVIADIPVQH- 169
Cdd:PRK12826    8 VALVTGAARGIGRAIAVRL-AADGAE-VIVVDICGDDAAATAELVEAA---GGKARARQVDVRDRAALKAAVAAGVEDFg 82

                          90
                  ....*....|....*
gi 1769863894 170 PLSGVIHTAGALDDA 184
Cdd:PRK12826   83 RLDILVANAGIFPLT 97

retinol dehydrogenase (retinol-DH), Light dependent Protochlorophyllide (Pchlide) OxidoReductase (LPOR) and related proteins, classical (c) SDRs; Classical SDR subgroup containing retinol-DHs, LPORs, and related proteins. Retinol is processed by a medium chain alcohol dehydrogenase followed by retinol-DHs. Pchlide reductases act in chlorophyll biosynthesis. There are distinct enzymes that catalyze Pchlide reduction in light or dark conditions. Light-dependent reduction is via an NADP-dependent SDR, LPOR. Proteins in this subfamily share the glycine-rich NAD-binding motif of the classical SDRs, have a partial match to the canonical active site tetrad, but lack the typical active site Ser. This subgroup includes the human proteins: retinol dehydrogenase -12, -13 ,and -14, dehydrogenase/reductase SDR family member (DHRS)-12 , -13 and -X (a DHRS on chromosome X), and WWOX (WW domain-containing oxidoreductase), as well as a Neurospora crassa SDR encoded by the blue light inducible bli-4 gene. SDRs are a functionally diverse family of oxidoreductases that have a single domain with a structurally conserved Rossmann fold (alpha/beta folding pattern with a central beta-sheet), an NAD(P)(H)-binding region, and a structurally diverse C-terminal region. Classical SDRs are typically about 250 residues long, while extended SDRs are approximately 350 residues. Sequence identity between different SDR enzymes are typically in the 15-30% range, but the enzymes share the Rossmann fold NAD-binding motif and characteristic NAD-binding and catalytic sequence patterns. These enzymes catalyze a wide range of activities including the metabolism of steroids, cofactors, carbohydrates, lipids, aromatic compounds, and amino acids, and act in redox sensing. Classical SDRs have an TGXXX[AG]XG cofactor binding motif and a YXXXK active site motif, with the Tyr residue of the active site motif serving as a critical catalytic residue (Tyr-151, human 15-hydroxyprostaglandin dehydrogenase (15-PGDH) numbering). In addition to the Tyr and Lys, there is often an upstream Ser (Ser-138, 15-PGDH numbering) and/or an Asn (Asn-107, 15-PGDH numbering) contributing to the active site; while substrate binding is in the C-terminal region, which determines specificity. The standard reaction mechanism is a 4-pro-S hydride transfer and proton relay involving the conserved Tyr and Lys, a water molecule stabilized by Asn, and nicotinamide. Extended SDRs have additional elements in the C-terminal region, and typically have a TGXXGXXG cofactor binding motif. Complex (multidomain) SDRs such as ketoreductase domains of fatty acid synthase have a GGXGXXG NAD(P)-binding motif and an altered active site motif (YXXXN). Fungal type ketoacyl reductases have a TGXXXGX(1-2)G NAD(P)-binding motif. Some atypical SDRs have lost catalytic activity and/or have an unusual NAD(P)-binding motif and missing or unusual active site residues. Reactions catalyzed within the SDR family include isomerization, decarboxylation, epimerization, C=N bond reduction, dehydratase activity, dehalogenation, Enoyl-CoA reduction, and carbonyl-alcohol oxidoreduction.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894  91 TVLITGGTGMAGSAVARHvVARHGVRnLVLVSR---RGPDApgaaELVAELAAAGAQVQVVACDAAD----RAALAKVIA 163
Cdd:cd05327     3 VVVITGANSGIGKETARE-LAKRGAH-VIIACRneeKGEEA----AAEIKKETGNAKVEVIQLDLSSlasvRQFAEEFLA 76

                          90
                  ....*....|....*...
gi 1769863894 164 DIPvqhPLSGVIHTAGAL 181
Cdd:cd05327    77 RFP---RLDILINNAGIM 91

alcohol dehydrogenase and quinone reductase-like medium chain degydrogenases/reductases; Members identified as zinc-dependent alcohol dehydrogenases and quinone oxidoreductase. QOR catalyzes the conversion of a quinone + NAD(P)H to a hydroquinone + NAD(P)+. Quinones are cyclic diones derived from aromatic compounds. Membrane bound QOR actin the respiratory chains of bacteria and mitochondria, while soluble QOR acts to protect from toxic quinones (e.g. DT-diaphorase) or as a soluble eye-lens protein in some vertebrates (e.g. zeta-crystalin). QOR reduces quinones through a semi-quinone intermediate via a NAD(P)H-dependent single electron transfer. QOR is a member of the medium chain dehydrogenase/reductase family, but lacks the zinc-binding sites of the prototypical alcohol dehydrogenases of this group. NAD(P)(H)-dependent oxidoreductases are the major enzymes in the interconversion of alcohols and aldehydes, or ketones. Alcohol dehydrogenase in the liver converts ethanol and NAD+ to acetaldehyde and NADH, while in yeast and some other microorganisms ADH catalyzes the conversion acetaldehyde to ethanol in alcoholic fermentation. ADH is a member of the medium chain alcohol dehydrogenase family (MDR), which has a NAD(P)(H)-binding domain in a Rossmann fold of a beta-alpha form. The NAD(H)-binding region is comprised of 2 structurally similar halves, each of which contacts a mononucleotide. A GxGxxG motif after the first mononucleotide contact half allows the close contact of the coenzyme with the ADH backbone. The N-terminal catalytic domain has a distant homology to GroES. These proteins typically form dimers (typically higher plants, mammals) or tetramers (yeast, bacteria), and have 2 tightly bound zinc atoms per subunit, a catalytic zinc at the active site and a structural zinc in a lobe of the catalytic domain. NAD(H) binding occurs in the cleft between the catalytic and coenzyme-binding domains at the active site, and coenzyme binding induces a conformational closing of this cleft. Coenzyme binding typically precedes and contributes to substrate binding. In human ADH catalysis, the zinc ion helps coordinate the alcohol, followed by deprotonation of a histidine, the ribose of NAD, a serine, then the alcohol, which allows the transfer of a hydride to NAD+, creating NADH and a zinc-bound aldehyde or ketone. In yeast and some bacteria, the active site zinc binds an aldehyde, polarizing it, and leading to the reverse reaction.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1769863894   8 DPGVIAQQYPGVRYRAFDLfEPGPDRiaqiLAELATLFGDGVLRPLPVTTFDVRCAPAALRYLSQARHTGKVV 80
Cdd:cd05289   241 PPAEQAAKRRGVRAGFVFV-EPDGEQ----LAELAELVEAGKLRPVVDRVFPLEDAAEAHERLESGHARGKVV 308

Short-chain dehydrogenase involved in D-alanine esterification of teichoic acids [Cell wall/membrane/envelope biogenesis, Lipid transport and metabolism];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1769863894  91 TVLITGGTGMAGSAVARHVVARHgvrNLVLVSRRGPDA--------PGaaelvaelaaagaqVQVVACDAADRAALAKVI 162
Cdd:COG3967     7 TILITGGTSGIGLALAKRLHARG---NTVIITGRREEKleeaaaanPG--------------LHTIVLDVADPASIAALA 69

                          90
                  ....*....|....*...
gi 1769863894 163 ADIPVQHP-LSGVIHTAG 179
Cdd:COG3967    70 EQVTAEFPdLNVLINNAG 87

PIG3 p53-inducible quinone oxidoreductase; PIG3 p53-inducible quinone oxidoreductase, a medium chain dehydrogenase/reductase family member, acts in the apoptotic pathway. PIG3 reduces ortho-quinones, but its apoptotic activity has been attributed to oxidative stress generation, since overexpression of PIG3 accumulates reactive oxygen species. PIG3 resembles the MDR family member quinone reductases, which catalyze the reduction of quinone to hydroxyquinone. NAD(P)(H)-dependent oxidoreductases are the major enzymes in the interconversion of alcohols and aldehydes or ketones. Alcohol dehydrogenase in the liver converts ethanol and NAD+ to acetaldehyde and NADH, while in yeast and some other microorganisms ADH catalyzes the conversion acetaldehyde to ethanol in alcoholic fermentation. ADH is a member of the medium chain alcohol dehydrogenase family (MDR), which has a NAD(P)(H)-binding domain in a Rossmann fold of a beta-alpha form. The NAD(H)-binding region is comprised of 2 structurally similar halves, each of which contacts a mononucleotide. A GxGxxG motif after the first mononucleotide contact half allows the close contact of the coenzyme with the ADH backbone. The N-terminal catalytic domain has a distant homology to GroES. These proteins typically form dimers (typically higher plants, mammals) or tetramers (yeast, bacteria), and have 2 tightly bound zinc atoms per subunit, a catalytic zinc at the active site, and a structural zinc in a lobe of the catalytic domain. NAD(H) binding occurs in the cleft between the catalytic and coenzyme-binding domains at the active site, and coenzyme binding induces a conformational closing of this cleft. Coenzyme binding typically precedes and contributes to substrate binding. In human ADH catalysis, the zinc ion helps coordinate the alcohol, followed by deprotonation of a histidine, the ribose of NAD, a serine, then the alcohol, which allows the transfer of a hydride to NAD+, creating NADH and a zinc-bound aldehyde or ketone. In yeast and some bacteria, the active site zinc binds an aldehyde, polarizing it, and leading to the reverse reaction.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 1769863894  35 AQILAELAT----LFGDGVLRPLPVTTFDVRCAPAALRYLSQARHTGKVV 80
Cdd:cd05276   273 AALAAAFREhvwpLFASGRIRPVIDKVFPLEEAAEAHRRMESNEHIGKIV 322

Polysaccharide biosynthesis protein; This is a family of diverse bacterial polysaccharide biosynthesis proteins including the CapD protein, WalL protein mannosyl-transferase and several putative epimerases (e.g. WbiI).

                          10        20        30
                  ....*....|....*....|....*....|..
gi 1769863894  92 VLITGGTGMAGSAVARHvVARHGVRNLVLVSR 123
Cdd:pfam02719   1 VLVTGGGGSIGSELCRQ-ILKFNPKKIILFSR 31