MutT homolog-1 and similar proteins; MutT homolog-1 (MTH1), also known as NUDIX (nucleoside diphosphate-linked moiety X)) motif 1/Nudt1, is a member of the NUDIX hydrolase superfamily. MTH1, the mammalian counterpart of MutT, hydrolyzes oxidized purine nucleoside triphosphates, such as 8-oxo-dGTP and 2-hydroxy-ATP, to monophosphates, thereby preventing the incorporation of such oxygen radicals during replication. This is an important step in the repair mechanism in genomic and mitochondrial DNA. Like other members of the NUDIX family, it requires a divalent cation, such as Mg2+ or Mn2+, for activity, and contain the NUDIX motif, a highly conserved 23-residue block (GX5EX7REUXEEXGU, where U = I, L or V), that functions as a metal binding and catalytic site. MTH1 is predominantly localized in the cytoplasm and mitochondria. Structurally, this enzyme adopts a similar fold to MutT despite low sequence similarity outside the conserved NUDIX motif. The most distinctive structural difference between MutT and MTH1 is the presence of a beta-hairpin, which is absent in MutT. This results in a much deeper and narrower substrate binding pocket. Mechanistically, MTH1 contains dual specificity for nucleotides that contain 2-OH-adenine bases and those that contain 8-oxo-guanine bases.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2796347910   2 ITTLCYLEKDNKYLMLHRTKKENdinKNKWLGVGGKLEKNETPEQCLFREVKEETGLTLIDYIHRGIVIF-NFNDDEPLY 80
Cdd:cd18886     1 KYTLCFIIRDDEVLLLNRNKKPN---MGKWNGVGGKLEPGESPEECAIREVFEETGLELEDLQLRGIVTFpSFDGGEDWL 77

                          90       100       110       120       130       140       150
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2796347910  81 MYLYTSKNFSGKVQECS-EGDLKWIDKSKIYDLNLWEGDKIFLDLLNKDTPFFYLTLDYEDDNLISSDLK 149
Cdd:cd18886    78 MYVFLAEAFSGELVESDrEGILAWVPIDWLLNLPLWEGDRYFLPLLFDNEPPFEGKFHYDGGRLLDYEVN 147

MutT homolog-1 and similar proteins; MutT homolog-1 (MTH1), also known as NUDIX (nucleoside diphosphate-linked moiety X)) motif 1/Nudt1, is a member of the NUDIX hydrolase superfamily. MTH1, the mammalian counterpart of MutT, hydrolyzes oxidized purine nucleoside triphosphates, such as 8-oxo-dGTP and 2-hydroxy-ATP, to monophosphates, thereby preventing the incorporation of such oxygen radicals during replication. This is an important step in the repair mechanism in genomic and mitochondrial DNA. Like other members of the NUDIX family, it requires a divalent cation, such as Mg2+ or Mn2+, for activity, and contain the NUDIX motif, a highly conserved 23-residue block (GX5EX7REUXEEXGU, where U = I, L or V), that functions as a metal binding and catalytic site. MTH1 is predominantly localized in the cytoplasm and mitochondria. Structurally, this enzyme adopts a similar fold to MutT despite low sequence similarity outside the conserved NUDIX motif. The most distinctive structural difference between MutT and MTH1 is the presence of a beta-hairpin, which is absent in MutT. This results in a much deeper and narrower substrate binding pocket. Mechanistically, MTH1 contains dual specificity for nucleotides that contain 2-OH-adenine bases and those that contain 8-oxo-guanine bases.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2796347910   2 ITTLCYLEKDNKYLMLHRTKKENdinKNKWLGVGGKLEKNETPEQCLFREVKEETGLTLIDYIHRGIVIF-NFNDDEPLY 80
Cdd:cd18886     1 KYTLCFIIRDDEVLLLNRNKKPN---MGKWNGVGGKLEPGESPEECAIREVFEETGLELEDLQLRGIVTFpSFDGGEDWL 77

                          90       100       110       120       130       140       150
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2796347910  81 MYLYTSKNFSGKVQECS-EGDLKWIDKSKIYDLNLWEGDKIFLDLLNKDTPFFYLTLDYEDDNLISSDLK 149
Cdd:cd18886    78 MYVFLAEAFSGELVESDrEGILAWVPIDWLLNLPLWEGDRYFLPLLFDNEPPFEGKFHYDGGRLLDYEVN 147

NUDIX domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2796347910   8 LEKDNKYLMLHRTKKendINKNKWLGVGGKLEKNETPEQCLFREVKEETGLT-----LIDYIHRGIVIFNFNDDEPLYMY 82
Cdd:pfam00293  11 LNEKGRVLLVRRSKK---PFPGWWSLPGGKVEPGETPEEAARRELEEETGLEpelleLLGSLHYLAPFDGRFPDEHEILY 87

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|....*.
gi 2796347910  83 LYTSKnFSGKVQECSEG---DLKWIDKSKIYDLNLWEGDKIFLDLL 125
Cdd:pfam00293  88 VFLAE-VEGELEPDPDGeveEVRWVPLEELLLLKLAPGDRKLLPWL 132

mutator mutT protein; All proteins in this family for which functions are known are involved in repairing oxidative damage to dGTP (they are 8-oxo-dGTPases). This family is based on the phylogenomic analysis of JA Eisen (1999, Ph.D. Thesis, Stanford University). Lowering the threshold picks up members of MutT superfamily well. [DNA metabolism, DNA replication, recombination, and repair]

                          10        20        30
                  ....*....|....*....|....*....|.
gi 2796347910  29 NKWLGVGGKLEKNETPEQCLFREVKEETGLT 59
Cdd:TIGR00586  31 KLLEFPGGKEEGGETPEQAVVRELEEEIGIP 61

MutT homolog-1 and similar proteins; MutT homolog-1 (MTH1), also known as NUDIX (nucleoside diphosphate-linked moiety X)) motif 1/Nudt1, is a member of the NUDIX hydrolase superfamily. MTH1, the mammalian counterpart of MutT, hydrolyzes oxidized purine nucleoside triphosphates, such as 8-oxo-dGTP and 2-hydroxy-ATP, to monophosphates, thereby preventing the incorporation of such oxygen radicals during replication. This is an important step in the repair mechanism in genomic and mitochondrial DNA. Like other members of the NUDIX family, it requires a divalent cation, such as Mg2+ or Mn2+, for activity, and contain the NUDIX motif, a highly conserved 23-residue block (GX5EX7REUXEEXGU, where U = I, L or V), that functions as a metal binding and catalytic site. MTH1 is predominantly localized in the cytoplasm and mitochondria. Structurally, this enzyme adopts a similar fold to MutT despite low sequence similarity outside the conserved NUDIX motif. The most distinctive structural difference between MutT and MTH1 is the presence of a beta-hairpin, which is absent in MutT. This results in a much deeper and narrower substrate binding pocket. Mechanistically, MTH1 contains dual specificity for nucleotides that contain 2-OH-adenine bases and those that contain 8-oxo-guanine bases.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2796347910   2 ITTLCYLEKDNKYLMLHRTKKENdinKNKWLGVGGKLEKNETPEQCLFREVKEETGLTLIDYIHRGIVIF-NFNDDEPLY 80
Cdd:cd18886     1 KYTLCFIIRDDEVLLLNRNKKPN---MGKWNGVGGKLEPGESPEECAIREVFEETGLELEDLQLRGIVTFpSFDGGEDWL 77

                          90       100       110       120       130       140       150
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2796347910  81 MYLYTSKNFSGKVQECS-EGDLKWIDKSKIYDLNLWEGDKIFLDLLNKDTPFFYLTLDYEDDNLISSDLK 149
Cdd:cd18886    78 MYVFLAEAFSGELVESDrEGILAWVPIDWLLNLPLWEGDRYFLPLLFDNEPPFEGKFHYDGGRLLDYEVN 147

uncharacterized NUDIX hydrolase subfamily; NUDIX hydrolase is a superfamily of enzymes found in all three kingdoms of life, and it catalyzes the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+ for their activity. Members of this family are recognized by a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which forms a structural motif that functions as a metal binding and catalytic site. Substrates of NUDIX hydrolase include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the NUDIX hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance and "house-cleaning" enzymes. Substrate specificity is used to define child families within the superfamily. Differences in substrate specificity are determined by the N-terminal extension or by residues in variable loop regions. Mechanistically, substrate hydrolysis occurs by a nucleophilic substitution reaction, with variation in the numbers and roles of divalent cations required. This superfamily consists of at least nine families: IPP (isopentenyl diphosphate) isomerase, ADP ribose pyrophosphatase, mutT pyrophosphohydrolase, coenzyme-A pyrophosphatase, MTH1-7,8-dihydro-8-oxoguanine-triphosphatase, diadenosine tetraphosphate hydrolase, NADH pyrophosphatase, GDP-mannose hydrolase and the c-terminal portion of the mutY adenine glycosylase.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2796347910   2 ITTLCYLEKD-NKYLMLHRTKKendiNKNKWLGVGGKLEKNETPEQCLFREVKEETGLTLIDYIHRGIVIFnFNDDEPLY 80
Cdd:cd18875     3 LTNMCMIYDGeDRVLVLDRVKK----DWGGYTFPGGHVEPGESFVDSVIREVKEETGLTIKNPELCGIKQW-INPDGERY 77

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2796347910  81 M-YLYTSKNFSGKVQECSEGDLKWIDKSKIYDLNLWEGDKIFLDLLNKDTPF-FYLTLDYEDDN 142
Cdd:cd18875    78 IvFLYKTDHFSGELLSSEEGELFWIPIEELKKLPLATDFDEMLRVFESDDLSeFFYYREGDDWN 141

ADP-ribose pyrophosphatase YjhB, NUDIX family [Nucleotide transport and metabolism];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2796347910   8 LEKDNKYLMLHRTkkeNDINKNKWLGVGGKLEKNETPEQCLFREVKEETGLTLIDYIHRGivIFNFNDDEPLYMYLYTSK 87
Cdd:COG1051    14 FRKDGRVLLVRRA---DEPGKGLWALPGGKVEPGETPEEAALRELREETGLEVEVLELLG--VFDHPDRGHVVSVAFLAE 88

                          90       100       110
                  ....*....|....*....|....*....|....*..
gi 2796347910  88 NFSGKVQECSEG-DLKWIDKSKIYDLNLWEGDKIFLD 123
Cdd:COG1051    89 VLSGEPRADDEIdEARWFPLDELPELAFTPADHEILE 125

8-oxo-dGTP pyrophosphatase MutT and related house-cleaning NTP pyrophosphohydrolases, NUDIX family [Defense mechanisms];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2796347910   8 LEKDNKYLMLHRTKkeNDINKNKWLGVGGKLEKNETPEQCLFREVKEETGLTLIDYIHRGIVIFNFNDDEPLYMYL--YT 85
Cdd:COG0494    21 LDDDGRVLLVRRYR--YGVGPGLWEFPGGKIEPGESPEEAALRELREETGLTAEDLELLGELPSPGYTDEKVHVFLarGL 98

                          90       100
                  ....*....|....*....|....*...
gi 2796347910  86 SKNFSGKVQECSEG-DLKWIDKSKIYDL 112
Cdd:COG0494    99 GPGEEVGLDDEDEFiEVRWVPLDEALAL 126

MutT pyrophosphohydrolase; The MutT pyrophosphohydrolase is a prototypical NUDIX hydrolase that catalyzes the hydrolysis of nucleoside and deoxynucleoside triphosphates (NTPs and dNTPs) by substitution at a beta-phosphorus to yield a nucleotide monophosphate (NMP) and inorganic pyrophosphate (PPi). This enzyme requires two divalent cations for activity; one coordinates the phosphoryl groups of the NTP/dNTP substrate, and the other coordinates to the enzyme. It also contains the NUDIX motif, a highly conserved 23-residue block (GX5EX7REUXEEXGU, where U = I, L or V), that functions as metal binding and catalytic site. MutT pyrophosphohydrolase is important in preventing errors in DNA replication by hydrolyzing mutagenic nucleotides such as 8-oxo-dGTP (a product of oxidative damage), which can mispair with template adenine during DNA replication, to guanine nucleotides.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2796347910   8 LEKDNKYLMLHRtkKENDINKNKWLGVGGKLEKNETPEQCLFREVKEETGLTLIDYIHRGIVIFNfNDDEPLYMYLYTSK 87
Cdd:cd03425     8 IVDDGRVLIAQR--PEGKHLAGLWEFPGGKVEPGETPEQALVRELREELGIEVEVGEPLGTVEHD-YPDFHVRLHVYLCT 84

                          90       100       110
                  ....*....|....*....|....*....|....*...
gi 2796347910  88 NFSGKVQECSEGDLKWIDKSKIYDLNLWEGDKIFLDLL 125
Cdd:cd03425    85 LWSGEPQLLEHQELRWVTPEELDDLDWLPADIPIVEAL 122

uncharacterized NUDIX hydrolase subfamily; NUDIX hydrolase is a superfamily of enzymes found in all three kingdoms of life, and it catalyzes the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+ for their activity. Members of this family are recognized by a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which forms a structural motif that functions as a metal binding and catalytic site. Substrates of NUDIX hydrolase include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the NUDIX hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance and "house-cleaning" enzymes. Substrate specificity is used to define child families within the superfamily. Differences in substrate specificity are determined by the N-terminal extension or by residues in variable loop regions. Mechanistically, substrate hydrolysis occurs by a nucleophilic substitution reaction, with variation in the numbers and roles of divalent cations required. This superfamily consists of at least nine families: IPP (isopentenyl diphosphate) isomerase, ADP ribose pyrophosphatase, mutT pyrophosphohydrolase, coenzyme-A pyrophosphatase, MTH1-7,8-dihydro-8-oxoguanine-triphosphatase, diadenosine tetraphosphate hydrolase, NADH pyrophosphatase, GDP-mannose hydrolase and the c-terminal portion of the mutY adenine glycosylase.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 2796347910  11 DNKYLMLHRTKKENDINKNKWLGVGGKLEKNETPEQCLFREVKEETGLTL 60
Cdd:cd18882    12 RGKVLLQLRDDKPGIPYPGYWGLFGGHLEPGETPEEAIRRELEEEIGYEP 61

dihydroneopterin hydrolase; DHNTP pyrophosphatase (DHNTPase) catalyzes the hydrolysis of dihydroneopterin triphosphate (DHNTP) to dihydroneopterin monophosphate (DHNMP) and pyrophosphate,the second step in the pterin branch of the folate synthesis pathway in bacteria. Members of the NUDIX hydrolase superfamily catalyze the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+, for their activity and contain a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which functions as a metal binding and catalytic site. Substrates of NUDIX hydrolases include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the NUDIX hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance _ "house-cleaning" enzymes. Substrate specificity is used to define families within the superfamily. Differences in substrate specificity are determined by the N-terminal extension or by residues in variable loop regions. Mechanistically, substrate hydrolysis occurs by a nucleophilic substitution reaction, with variation in the numbers and roles of divalent cations required.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|..
gi 2796347910  12 NKYLMLHRTKKENdinknKWLGVGGKLEKNETPEQCLFREVKEETGLTLIDY 63
Cdd:cd04664    14 GEVLLLKRTDDGG-----FWQSVTGGIEDGETPWQAALRELKEETGLDPLEL 60

ADP-ribose pyrophosphatase and similar proteins; ADP-ribose pyrophosphatase (ADPRase; EC 3.6.1.13) catalyzes the hydrolysis of ADP-ribose to AMP and ribose-5-P. Like other members of the NUDIX hydrolase superfamily of enzymes, it is thought to require a divalent cation, such as Mg2+, for its activity. It also contains a 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V) which functions as a metal binding site/catalytic site. In addition to the NUDIX motif, there are additional conserved amino acid residues, distal from the signature sequence, that correlate with substrate specificity. In humans, there are four distinct ADPRase activities, three putative cytosolic (ADPRase-I, -II, and -Mn) and a single mitochondrial enzyme (ADPRase-m). ADPRase-m is also known as NUDT9. It can be distinugished from the cytosolic ADPRase by a N-terminal target sequence unique to mitochondrial ADPRase. NUDT9 functions as a monomer.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|..
gi 2796347910   8 LEKDNKYLMlhrTKKENDINKNKWLGVGGKLEKNETPEQCLFREVKEETGLT 59
Cdd:cd04691     8 VVKEGKVLL---VKRAYGPGKGRWTLPGGFVEEGETLDEAIVREVLEETGID 56

ADP-ribose pyrophosphatase; ADP-ribose pyrophosphatase (ADPRase; EC 3.6.1.13) catalyzes the hydrolysis of ADP-ribose to AMP and ribose-5-P. Like other members of the NUDIX hydrolase superfamily of enzymes, it is thought to require a divalent cation, such as Mg2+, for its activity. It also contains a 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V) which functions as a metal binding site/catalytic site. In addition to the NUDIX motif, there are additional conserved amino acid residues, distal from the signature sequence, that correlate with substrate specificity. In humans, there are four distinct ADPRase activities, three putative cytosolic (ADPRase-I, -II, and -Mn) and a single mitochondrial enzyme (ADPRase-m). ADPRase-m is also known as NUDT9. It can be distinugished from the cytosolic ADPRase by a N-terminal target sequence unique to mitochondrial ADPRase. NUDT9 functions as a monomer.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2796347910   8 LEKDNKYLMLHRTkkeNDINKNKWlGV-GGKLEKNETPEQCLFREVKEETGL--------TLIDYIHRGivifnfNDDEP 78
Cdd:cd04673     8 VFRDGRVLLVRRG---NPPDAGLW-SFpGGKVELGETLEDAALRELREETGLeaevvgllTVVDVIERD------EAGRV 77

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|...
gi 2796347910  79 LYMYL---YTSKNFSGKVQECSE-GDLKWIDKSKIYDLNLWEG 117
Cdd:cd04673    78 RFHYVildFLAEWVSGEPVAGDDaLDARWFSLEELDGLPLTPG 120

uncharacterized NUDIX hydrolase subfamily; NUDIX hydrolase is a superfamily of enzymes found in all three kingdoms of life, and it catalyzes the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+ for their activity. Members of this family are recognized by a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which forms a structural motif that functions as a metal binding and catalytic site. Substrates of NUDIX hydrolase include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the NUDIX hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance and "house-cleaning" enzymes. Substrate specificity is used to define child families within the superfamily. Differences in substrate specificity are determined by the N-terminal extension or by residues in variable loop regions. Mechanistically, substrate hydrolysis occurs by a nucleophilic substitution reaction, with variation in the numbers and roles of divalent cations required. This superfamily consists of at least nine families: IPP (isopentenyl diphosphate) isomerase, ADP ribose pyrophosphatase, mutT pyrophosphohydrolase, coenzyme-A pyrophosphatase, MTH1-7,8-dihydro-8-oxoguanine-triphosphatase, diadenosine tetraphosphate hydrolase, NADH pyrophosphatase, GDP-mannose hydrolase and the c-terminal portion of the mutY adenine glycosylase.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 2796347910   9 EKDNKYLMLHrtkkendINK-NKWLGVGGKLEKNETPEQCLFREVKEETGLTLIDYIHRGIVIF 71
Cdd:cd03674    11 PDRGKVLLVH-------HRKlGRWLQPGGHVEPDEDPLEAALREAREETGLDVELLSPLSPDPL 67

uncharacterized NUDIX hydrolase subfamily; Contains a crystal structure of the NUDIX hydrolase from Enterococcus faecalis, which has an unknown function. NUDIX hydrolase is a superfamily of enzymes found in all three kingdoms of life, and it catalyzes the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+ for their activity. Members of this family are recognized by a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which forms a structural motif that functions as a metal binding and catalytic site. Substrates of NUDIX hydrolase include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the NUDIX hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance and "house-cleaning" enzymes. Substrate specificity is used to define child families within the superfamily. Differences in substrate specificity are determined by the N-terminal extension or by residues in variable loop regions. Mechanistically, substrate hydrolysis occurs by a nucleophilic substitution reaction, with variation in the numbers and roles of divalent cations required. This superfamily consists of at least nine families: IPP (isopentenyl diphosphate) isomerase, ADP ribose pyrophosphatase, mutT pyrophosphohydrolase, coenzyme-A pyrophosphatase, MTH1-7,8-dihydro-8-oxoguanine-triphosphatase, diadenosine tetraphosphate hydrolase, NADH pyrophosphatase, GDP-mannose hydrolase and the c-terminal portion of the mutY adenine glycosylase.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2796347910  35 GGKLEKNETPEQCLFREVKEETGLT--LIDYIHRGiVIFNFNDDEPLYM----YLYTSKNFSgKVQECSEGD--LKWIDK 106
Cdd:cd04684    43 GGGIEPGETPEEALHREVLEETGWEieIGEFLGNA-SRYFYSPDYDRYYlnigYFYLAELVR-KVSEPTEEDheLVWLPP 120

                          90
                  ....*....|....*.
gi 2796347910 107 SKIYDLNLWEGDKIFL 122
Cdd:cd04684   121 EEAADLLKHEHHRWAV 136

uncharacterized NUDIX hydrolase subfamily; NUDIX hydrolase is a superfamily of enzymes found in all three kingdoms of life, and it catalyzes the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+ for their activity. Members of this family are recognized by a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which forms a structural motif that functions as a metal binding and catalytic site. Substrates of NUDIX hydrolase include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the NUDIX hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance and "house-cleaning" enzymes. Substrate specificity is used to define child families within the superfamily. Differences in substrate specificity are determined by the N-terminal extension or by residues in variable loop regions. Mechanistically, substrate hydrolysis occurs by a nucleophilic substitution reaction, with variation in the numbers and roles of divalent cations required. This superfamily consists of at least nine families: IPP (isopentenyl diphosphate) isomerase, ADP ribose pyrophosphatase, mutT pyrophosphohydrolase, coenzyme-A pyrophosphatase, MTH1-7,8-dihydro-8-oxoguanine-triphosphatase, diadenosine tetraphosphate hydrolase, NADH pyrophosphatase, GDP-mannose hydrolase and the c-terminal portion of the mutY adenine glycosylase.

                          10        20        30
                  ....*....|....*....|....*....|
gi 2796347910  31 WLGVGGKLEKNETPEQCLFREVKEETGLTL 60
Cdd:cd04685    30 WFTPGGGVEPGESPEQAAVRELREETGLRL 59

uncharacterized NUDIX hydrolase subfamily; NUDIX hydrolase is a superfamily of enzymes found in all three kingdoms of life, and it catalyzes the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+ for their activity. Members of this family are recognized by a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which forms a structural motif that functions as a metal binding and catalytic site. Substrates of NUDIX hydrolase include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the NUDIX hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance and "house-cleaning" enzymes. Substrate specificity is used to define child families within the superfamily. Differences in substrate specificity are determined by the N-terminal extension or by residues in variable loop regions. Mechanistically, substrate hydrolysis occurs by a nucleophilic substitution reaction, with variation in the numbers and roles of divalent cations required. This superfamily consists of at least nine families: IPP (isopentenyl diphosphate) isomerase, ADP ribose pyrophosphatase, mutT pyrophosphohydrolase, coenzyme-A pyrophosphatase, MTH1-7,8-dihydro-8-oxoguanine-triphosphatase, diadenosine tetraphosphate hydrolase, NADH pyrophosphatase, GDP-mannose hydrolase and the c-terminal portion of the mutY adenine glycosylase.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2796347910  11 DNKYLMLhRTKKENDinknKWLGVGGKLEKNETPEQCLFREVKEETGLTL--IDYIHRGIVIFN--FNDDEPLYMYLYTS 86
Cdd:cd18874    13 DGKVLLV-RSHKWND----LYGIPGGKVEWGETLEEALKREVKEETGLDItdIRFILVQESINSeeFHKPAHFVFVDYLA 87

                          90       100
                  ....*....|....*....|....*....
gi 2796347910  87 KNFSGKVQECSEGD-LKWIDKSKIYDLNL 114
Cdd:cd18874    88 RTDSSEVVLNEEAVeYLWVEPEEALKYPL 116

8-oxo-DGDP phosphatase; 8-oxo-DGDP phosphatase (8DGDPP; EC 3.6.1.55), also known as NUDIX (nucleoside diphosphate-linked moiety X)) motif 18/Nudt18; 2-hydroxy-DADP phosphatase; 7,8-dihydro-8-oxoguanine phosphatase, hydrolyzes 8-oxo-7,8-dihydroguanine (8-oxo-Gua)-containing deoxyribo- and ribonucleoside diphosphates to the monophosphates. Members of the NUDIX hydrolase superfamily catalyze the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+, for their activity and contain a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which functions as a metal binding and catalytic site. Substrates of NUDIX hydrolases include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the NUDIX hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance _ "house-cleaning" enzymes. Substrate specificity is used to define families within the superfamily. Differences in substrate specificity are determined by the N-terminal extension or by residues in variable loop regions. Mechanistically, substrate hydrolysis occurs by a nucleophilic substitution reaction, with variation in the numbers and roles of divalent cations required.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 2796347910   8 LEKDNKYLMLHRTKKENdinKNKWLGVGGKLEKNETPEQCLFREVKEETGLTL 60
Cdd:cd04671     8 INEQGEVLMIQEAKRSC---RGKWYLPAGRVEPGESIVEAAKREVKEETGLKC 57

uncharacterized NUDIX hydrolase subfamily; NUDIX hydrolase is a superfamily of enzymes found in all three kingdoms of life, and it catalyzes the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+ for their activity. Members of this family are recognized by a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which forms a structural motif that functions as a metal binding and catalytic site. Substrates of NUDIX hydrolase include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the NUDIX hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance and "house-cleaning" enzymes. Substrate specificity is used to define child families within the superfamily. Differences in substrate specificity are determined by the N-terminal extension or by residues in variable loop regions. Mechanistically, substrate hydrolysis occurs by a nucleophilic substitution reaction, with variation in the numbers and roles of divalent cations required. This superfamily consists of at least nine families: IPP (isopentenyl diphosphate) isomerase, ADP ribose pyrophosphatase, mutT pyrophosphohydrolase, coenzyme-A pyrophosphatase, MTH1-7,8-dihydro-8-oxoguanine-triphosphatase, diadenosine tetraphosphate hydrolase, NADH pyrophosphatase, GDP-mannose hydrolase and the c-terminal portion of the mutY adenine glycosylase.

                          10        20        30
                  ....*....|....*....|....*....|...
gi 2796347910  28 KNKWLGVGGKLEKNETPEQCLFREVKEETGLTL 60
Cdd:cd18876    22 KDGWELPGGVVEAGESPLQAARREVREELGLDV 54

uncharacterized NUDIX hydrolase subfamily; NUDIX hydrolase is a superfamily of enzymes found in all three kingdoms of life, and it catalyzes the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+ for their activity. Members of this family are recognized by a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which forms a structural motif that functions as a metal binding and catalytic site. Substrates of NUDIX hydrolase include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the NUDIX hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance and "house-cleaning" enzymes. Substrate specificity is used to define child families within the superfamily. Differences in substrate specificity are determined by the N-terminal extension or by residues in variable loop regions. Mechanistically, substrate hydrolysis occurs by a nucleophilic substitution reaction, with variation in the numbers and roles of divalent cations required. This superfamily consists of at least nine families: IPP (isopentenyl diphosphate) isomerase, ADP ribose pyrophosphatase, mutT pyrophosphohydrolase, coenzyme-A pyrophosphatase, MTH1-7,8-dihydro-8-oxoguanine-triphosphatase, diadenosine tetraphosphate hydrolase, NADH pyrophosphatase, GDP-mannose hydrolase and the c-terminal portion of the mutY adenine glycosylase.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 2796347910   3 TTLCylEKDNKYLMLHRTKKendinknKWLGVGGKLEKNETPEQCLFREVKEETGL 58
Cdd:cd04667     4 TVIC--RRGDRILLVARRGG-------RWLLPGGKIEPGESPLEAAIRELKEETGL 50

dihydroneopterin triphosphate pyrophosphatase; Provisional

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2796347910  10 KDNKYLMLHRTKKendinKNKWLGVGGKLEKNETPEQCLFREVKEETGL-------TLIDYiHRGIV--IF 71
Cdd:PRK09438   17 PDLGVLMLQRADD-----PDFWQSVTGSLEEGETPAQTAIREVKEETGIdvlaeqlTLIDC-QRSIEyeIF 81

uncharacterized NUDIX hydrolase subfamily; NUDIX hydrolase is a superfamily of enzymes found in all three kingdoms of life, and it catalyzes the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+ for their activity. Members of this family are recognized by a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which forms a structural motif that functions as a metal binding and catalytic site. Substrates of NUDIX hydrolase include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the NUDIX hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance and "house-cleaning" enzymes. Substrate specificity is used to define child families within the superfamily. Differences in substrate specificity are determined by the N-terminal extension or by residues in variable loop regions. Mechanistically, substrate hydrolysis occurs by a nucleophilic substitution reaction, with variation in the numbers and roles of divalent cations required. This superfamily consists of at least nine families: IPP (isopentenyl diphosphate) isomerase, ADP ribose pyrophosphatase, mutT pyrophosphohydrolase, coenzyme-A pyrophosphatase, MTH1-7,8-dihydro-8-oxoguanine-triphosphatase, diadenosine tetraphosphate hydrolase, NADH pyrophosphatase, GDP-mannose hydrolase and the c-terminal portion of the mutY adenine glycosylase.

                          10        20
                  ....*....|....*....|....*....
gi 2796347910  34 VGGKLEKNETPEQCLFREVKEETGLTLID 62
Cdd:cd04663    31 PKGTVEPGESPEEAALRELAEETGLTGAR 59

MutT homolog-1 and similar proteins; MutT homolog-1 (MTH1), also known as NUDIX (nucleoside diphosphate-linked moiety X)) motif 1/Nudt1, is a member of the NUDIX hydrolase superfamily. MTH1, the mammalian counterpart of MutT, hydrolyzes oxidized purine nucleoside triphosphates, such as 8-oxo-dGTP and 2-hydroxy-ATP, to monophosphates, thereby preventing the incorporation of such oxygen radicals during replication. This is an important step in the repair mechanism in genomic and mitochondrial DNA. Like other members of the NUDIX family, it requires a divalent cation, such as Mg2+ or Mn2+, for activity, and contain the NUDIX motif, a highly conserved 23-residue block (GX5EX7REUXEEXGU, where U = I, L or V), that functions as a metal binding and catalytic site. MTH1 is predominantly localized in the cytoplasm and mitochondria. Structurally, this enzyme adopts a similar fold to MutT despite low sequence similarity outside the conserved NUDIX motif. The most distinctive structural difference between MutT and MTH1 is the presence of a beta-hairpin, which is absent in MutT. This results in a much deeper and narrower substrate binding pocket. Mechanistically, MTH1 contains dual specificity for nucleotides that contain 2-OH-adenine bases and those that contain 8-oxo-guanine bases.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 2796347910  10 KDNKYLMLHRTKkenDINKNKWLGVGGKLEKNETPEQCLFREVKEETGLTL 60
Cdd:cd04679    11 DDGRLLLVLRLR---APEAGHWGLPGGKVDWLETVEDAVRREILEELGLEI 58

mRNA decapping enzyme 2; mRNA decapping enzyme 2 (Dcp2p; EC 3.6.1.62), nucleoside diphosphate linked moiety X))-type motif 20/Nudt20, is required for degradation of mRNAs, both in normal mRNA turnover, and in nonsense-mediated mRNA decay (NMD). Its catalytic subunit, and Dcp1p are the two components of the decapping enzyme complex. Decapping is a key step in both general and nonsense-mediated 5'->3' mRNA-decay pathways. Dcp2p contains an all-alpha helical N-terminal domain and a C-terminal domain which has the NUDIX fold. While decapping is not dependent on the N-terminus of Dcp2p, it does affect its efficiency. Dcp1p binds the N-terminal domain of Dcp2p stimulating the decapping activity of Dcp2p. Decapping permits the degradation of the transcript and is a site of numerous control inputs. It is responsible for nonsense-mediated decay as well as AU-rich element (ARE)-mediated decay. In addition, it may also play a role in the levels of mRNA. Enzymes belonging to the NUDIX hydrolase superfamily require a divalent cation, such as Mg2+ or Mn2+, for their activity and are recognized by a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V).

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 2796347910  27 NKNKWLGVGGKLEKNETPEQCLFREVKEETGLTLIDYIHRGIVIFNFNDDEPLYMYL 83
Cdd:cd03672    24 SNSSWGFPKGKINKDESDADCAIREVYEETGFDISDLINDKDYIELTINGQRVRLYI 80

uncharacterized NUDIX hydrolase subfamily; NUDIX hydrolase is a superfamily of enzymes found in all three kingdoms of life, and it catalyzes the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+ for their activity. Members of this family are recognized by a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which forms a structural motif that functions as a metal binding and catalytic site. Substrates of NUDIX hydrolase include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the NUDIX hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance and "house-cleaning" enzymes. Substrate specificity is used to define child families within the superfamily. Differences in substrate specificity are determined by the N-terminal extension or by residues in variable loop regions. Mechanistically, substrate hydrolysis occurs by a nucleophilic substitution reaction, with variation in the numbers and roles of divalent cations required. This superfamily consists of at least nine families: IPP (isopentenyl diphosphate) isomerase, ADP ribose pyrophosphatase, mutT pyrophosphohydrolase, coenzyme-A pyrophosphatase, MTH1-7,8-dihydro-8-oxoguanine-triphosphatase, diadenosine tetraphosphate hydrolase, NADH pyrophosphatase, GDP-mannose hydrolase and the c-terminal portion of the mutY adenine glycosylase.

                          10        20        30
                  ....*....|....*....|....*....|....*..
gi 2796347910  35 GGKLEKNETPEQCLFREVKEETGLTLIDYIHRGIVIF 71
Cdd:cd04686    32 GGSQEFGESLEDALKREFAEETGMTVTSYDNLGVYDF 68

NADH pyrophosphatase; NADH pyrophosphatase, also known as NUDIX (nucleoside diphosphate linked moiety X)) motif 13/Nudt13, is thought to have NADH pyrophosphatase activity, be involved in NADH metabolic process and NADP catabolic process, catalyzing the cleavage of NADH into reduced nicotinamide mononucleotide (NMNH) and AMP, and located in mitochondrion. Like other members of the NUDIX family, it requires a divalent cation, such as Mg2+ or Mn2+, for activity. Members of this family are also recognized by the NUDIX motif, a highly conserved 23-residue block (GX5EX7REUXEEXGU, where U = I, L or V), that functions as a metal binding and catalytic site. A block of 8 conserved amino acids downstream of the NUDIX motif is thought to give NADH pyrophosphatase its specificity for NADH. NADH pyrophosphatase forms a dimer.

                          10        20
                  ....*....|....*....|....*...
gi 2796347910  39 EKNETPEQCLFREVKEETGLTL--IDYI 64
Cdd:cd03429    36 EPGETLEEAVRREVKEEVGLRVknVRYV 63

uncharacterized NUDIX hydrolase subfamily; NUDIX hydrolase is a superfamily of enzymes found in all three kingdoms of life, and it catalyzes the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+ for their activity. Members of this family are recognized by a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which forms a structural motif that functions as a metal binding and catalytic site. Substrates of NUDIX hydrolase include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the NUDIX hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance and "house-cleaning" enzymes. Substrate specificity is used to define child families within the superfamily. Differences in substrate specificity are determined by the N-terminal extension or by residues in variable loop regions. Mechanistically, substrate hydrolysis occurs by a nucleophilic substitution reaction, with variation in the numbers and roles of divalent cations required. This superfamily consists of at least nine families: IPP (isopentenyl diphosphate) isomerase, ADP ribose pyrophosphatase, mutT pyrophosphohydrolase, coenzyme-A pyrophosphatase, MTH1-7,8-dihydro-8-oxoguanine-triphosphatase, diadenosine tetraphosphate hydrolase, NADH pyrophosphatase, GDP-mannose hydrolase and the c-terminal portion of the mutY adenine glycosylase.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2796347910  10 KDNKYLMLHRTKKendiNKNKWLGVGGKLEKNETPEQCLFREVKEETGLTLIDYIHRGIVIFNFNDDEPLY 80
Cdd:cd04669     9 DDDKLLLIRRTKP----GEEYYVFPGGGIEPGETPEEAALREAVEELGLDVAVTLITLILRVLNDGTQHYF 75

RNA pyrophosphohydrolase; The initiation of mRNA degradation often requires deprotection of its 5' end. In eukaryotes, the 5'-methylguanosine (cap) structure is principally removed by the NUDIX family decapping enzyme Dcp2, yielding a 5'-monophosphorylated RNA that is a substrate for 5' exoribonucleases. In bacteria, the 5'-triphosphate group of primary transcripts is also converted to a 5' monophosphate by a NUDIX protein called RNA pyrophosphohydrolase (RppH), allowing access to both endo- and 5' exoribonucleases. NUDIX hydrolase is a superfamily of enzymes found in all three kingdoms of life, and it catalyzes the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+ for their activity. Members of this family are recognized by a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which forms a structural motif that functions as a metal binding and catalytic site. Substrates of NUDIX hydrolase include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the NUDIX hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance and "house-cleaning" enzymes. Substrate specificity is used to define child families within the superfamily. Differences in substrate specificity are determined by the N-terminal extension or by residues in variable loop regions. Mechanistically, substrate hydrolysis occurs by a nucleophilic substitution reaction, with variation in the numbers and roles of divalent cations required. This superfamily consists of at least nine families: IPP (isopentenyl diphosphate) isomerase, ADP ribose pyrophosphatase, mutT pyrophosphohydrolase, coenzyme-A pyrophosphatase, MTH1-7,8-dihydro-8-oxoguanine-triphosphatase, diadenosine tetraphosphate hydrolase, NADH pyrophosphatase, GDP-mannose hydrolase and the c-terminal portion of the mutY adenine glycosylase.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2796347910  28 KNKWLGV-----------GGKLEKNETPEQCLFREVKEETGLTL--IDYIHRGIVifnFNDDEPLYMYLYTSK 87
Cdd:cd04665    10 KGKWLFTrhkerrgwefpGGKREPGETIEEAARRELYEETGAVIfeLKPLGQYSV---HGKGQEFFGAVYYAE 79

nudix hydrolase

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 2796347910  35 GGKLEKNETPEQCLFREVKEETGLTlIDYIHRGIVIFNFNDDEP 78
Cdd:PLN02325   40 GGHLEFGESFEECAAREVKEETGLE-IEKIELLTVTNNVFLEEP 82

uncharacterized NUDIX hydrolase subfamily; NUDIX hydrolase is a superfamily of enzymes found in all three kingdoms of life, and it catalyzes the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+ for their activity. Members of this family are recognized by a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which forms a structural motif that functions as a metal binding and catalytic site. Substrates of NUDIX hydrolase include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the NUDIX hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance and "house-cleaning" enzymes. Substrate specificity is used to define child families within the superfamily. Differences in substrate specificity are determined by the N-terminal extension or by residues in variable loop regions. Mechanistically, substrate hydrolysis occurs by a nucleophilic substitution reaction, with variation in the numbers and roles of divalent cations required. This superfamily consists of at least nine families: IPP (isopentenyl diphosphate) isomerase, ADP ribose pyrophosphatase, mutT pyrophosphohydrolase, coenzyme-A pyrophosphatase, MTH1-7,8-dihydro-8-oxoguanine-triphosphatase, diadenosine tetraphosphate hydrolase, NADH pyrophosphatase, GDP-mannose hydrolase and the c-terminal portion of the mutY adenine glycosylase.

                          10        20        30
                  ....*....|....*....|....*....|....*.
gi 2796347910  23 ENDINKNKWLGVGGKLEKNETPEQCLFREVKEETGL 58
Cdd:cd04676    34 QRKGGLGLWSLPAGAIEPGEHPAEAVIREVREETGL 69

uncharacterized NUDIX hydrolase subfamily; Contains a crystal structure of the NUDIX hydrolase from Nitrosomonas europaea, which has an unknown function. NUDIX hydrolase is a superfamily of enzymes found in all three kingdoms of life, and it catalyzes the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+ for their activity. Members of this family are recognized by a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which forms a structural motif that functions as a metal binding and catalytic site. Substrates of NUDIX hydrolase include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the NUDIX hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance and "house-cleaning" enzymes. Substrate specificity is used to define child families within the superfamily. Differences in substrate specificity are determined by the N-terminal extension or by residues in variable loop regions. Mechanistically, substrate hydrolysis occurs by a nucleophilic substitution reaction, with variation in the numbers and roles of divalent cations required. This superfamily consists of at least nine families: IPP (isopentenyl diphosphate) isomerase, ADP ribose pyrophosphatase, mutT pyrophosphohydrolase, coenzyme-A pyrophosphatase, MTH1-7,8-dihydro-8-oxoguanine-triphosphatase, diadenosine tetraphosphate hydrolase, NADH pyrophosphatase, GDP-mannose hydrolase and the c-terminal portion of the mutY adenine glycosylase.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 2796347910   2 ITTLCYLEKDNKYLMLH-RTKKENDINKNkwlgvGGKLEKNETPEQCLFREVKEETGLTL 60
Cdd:cd03675     1 VTVAAVVERDGRFLLVEeETDGRLVLNQP-----AGHLEPGESLLEAAIRETLEETGWEV 55

ADP-ribose pyrophosphatase; ADP-ribose pyrophosphatase (ADPRase) (also known as NUDIX (Nucleoside diphosphate-linked moiety X)) motif 5; Nudt5) catalyzes the hydrolysis of ADP-ribose and a variety of additional ADP-sugar conjugates to AMP and ribose-5-phosphate. In humans, there are four distinct ADPRase activities, three putative cytosolic enzymes (ADPRase-I, -II, and -Mn) and a single mitochondrial enzyme (ADPRase-m). Human ADPRase-II is also referred to as NUDT5. It lacks the N-terminal target sequence unique to mitochondrial ADPRase. The different cytosolic types are distinguished by their specificities for substrate and specific requirement for metal ions. NUDT5 forms a homodimer. It also contains a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V) which functions as a metal binding site/catalytic site. In addition to the NUDIX motif, there are additional conserved amino acid residues, distal from the signature sequence, that correlate with substrate specificity.

                          10        20
                  ....*....|....*....|....
gi 2796347910  36 GKLEKNETPEQCLFREVKEETGLT 59
Cdd:cd18888    40 GLVDPGESPEQAALRELKEETGYT 63

uncharacterized NUDIX hydrolase subfamily; NUDIX hydrolase is a superfamily of enzymes found in all three kingdoms of life, and it catalyzes the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+ for their activity. Members of this family are recognized by a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which forms a structural motif that functions as a metal binding and catalytic site. Substrates of NUDIX hydrolase include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the NUDIX hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance and "house-cleaning" enzymes. Substrate specificity is used to define child families within the superfamily. Differences in substrate specificity are determined by the N-terminal extension or by residues in variable loop regions. Mechanistically, substrate hydrolysis occurs by a nucleophilic substitution reaction, with variation in the numbers and roles of divalent cations required. This superfamily consists of at least nine families: IPP (isopentenyl diphosphate) isomerase, ADP ribose pyrophosphatase, mutT pyrophosphohydrolase, coenzyme-A pyrophosphatase, MTH1-7,8-dihydro-8-oxoguanine-triphosphatase, diadenosine tetraphosphate hydrolase, NADH pyrophosphatase, GDP-mannose hydrolase and the c-terminal portion of the mutY adenine glycosylase.

                          10        20
                  ....*....|....*....|....*.
gi 2796347910  35 GGKLEKNETPEQCLFREVKEETGLTL 60
Cdd:cd04680    29 GGGVDKGETAEEAARRELREEAGVVL 54

GDP-mannose hydrolase (GDPMK), and similar proteins; GDP-mannose hydrolase (GDPMK) is a NUDIX enzyme that uses GDP-mannose as the preferred substrate. It is distinct from Nudix ADP-ribose hydrolases. GDPMK and ADP-ribose pyrophosphatase seem to use similar catalytic mechanism. However, GDPMK hydrolysis does not rely on a single glutamate as the catalytic base; rather, it is dependent on residues that coordinate the magnesium ions and residues that position the substrate properly for catalysis. Members of the NUDIX hydrolase superfamily catalyze the hydrolysis of NUcleoside DIphosphates linked to other moieties, X. Enzymes belonging to this superfamily require a divalent cation, such as Mg2+ or Mn2+, for their activity and contain a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which functions as a metal binding and catalytic site. Substrates of NUDIX hydrolases include intact and oxidatively damaged nucleoside triphosphates, dinucleoside polyphosphates, nucleotide-sugars and dinucleotide enzymes. These substrates are metabolites or cell signaling molecules that require regulation during different stages of the cell cycle or during periods of stress. In general, the role of the NUDIX hydrolase is to sanitize the nucleotide pools and to maintain cell viability, thereby serving as surveillance _ "house-cleaning" enzymes. Substrate specificity is used to define families within the superfamily. Differences in substrate specificity are determined by the N-terminal extension or by residues in variable loop regions. Mechanistically, substrate hydrolysis occurs by a nucleophilic substitution reaction, with variation in the numbers and roles of divalent cations required.

                          10        20
                  ....*....|....*....|....*..
gi 2796347910  34 VGGKLEKnETPEQCLFREVKEETGLTL 60
Cdd:cd24157    42 CAGLLDG-DDPEDCIRREAEEETGYRL 67