Nudix family hydrolase;

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 446751820   1 MKRRISVVGAVIFNENNEVLCALRSPTMTLPNYWEFPGGKIKNGEEPQVALVREIKEELGCSITVDEKVEEIEYEYETII 80
Cdd:PRK08999   1 SMKRIHVAAGVIRDADGRILLARRPEGKHQGGLWEFPGGKVEPGETVEQALARELQEELGIEVTAARPLITVRHDYPDKR 80

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*..
gi 446751820  81 VHLTTYKAQILEGIPKALEHTELKWVRVKDLNNLYWAPADIPTVESL 127
Cdd:PRK08999  81 VRLDVRRVTAWQGEPHGREGQPLAWVAPDELAVYPFPPANQPIVRAL 127

NUDIX domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 446751820    3 RRISVVGAVIFNENNEVLcALRSPTMTLPNYWEFPGGKIKNGEEPQVALVREIKEELGCSITVDEKVEEIEYEYETIIVH 82
Cdd:pfam00293   1 KRRVAVGVVLLNEKGRVL-LVRRSKKPFPGWWSLPGGKVEPGETPEEAARRELEEETGLEPELLELLGSLHYLAPFDGRF 79

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....
gi 446751820   83 ------LTTYKAQiLEGIPKAL---EHTELKWVRVKDLNNLYWAPADIPTVESL 127
Cdd:pfam00293  80 pdeheiLYVFLAE-VEGELEPDpdgEVEEVRWVPLEELLLLKLAPGDRKLLPWL 132

Nudix family hydrolase;

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 446751820   1 MKRRISVVGAVIFNENNEVLCALRSPTMTLPNYWEFPGGKIKNGEEPQVALVREIKEELGCSITVDEKVEEIEYEYETII 80
Cdd:PRK08999   1 SMKRIHVAAGVIRDADGRILLARRPEGKHQGGLWEFPGGKVEPGETVEQALARELQEELGIEVTAARPLITVRHDYPDKR 80

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*..
gi 446751820  81 VHLTTYKAQILEGIPKALEHTELKWVRVKDLNNLYWAPADIPTVESL 127
Cdd:PRK08999  81 VRLDVRRVTAWQGEPHGREGQPLAWVAPDELAVYPFPPANQPIVRAL 127

pyrimidine (deoxy)nucleoside triphosphate diphosphatase;

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 446751820   5 ISVVGAVIfNENNEVLCALRSPTMTLPNYWEFPGGKIKNGE-EPQvALVREIKEELGCSITVDEKVEEIEYEYETIIVHL 83
Cdd:PRK10546   4 IDVVAAII-ERDGKILLAQRPAHSDQAGLWEFAGGKVEPGEsQPQ-ALIRELREELGIEATVGEYVASHQREVSGRRIHL 81

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|...
gi 446751820  84 TTYKAQILEGIPKALEHTELKWVRVKDLNNLYWAPADIPTVES 126
Cdd:PRK10546  82 HAWHVPDFHGELQAHEHQALVWCTPEEALRYPLAPADIPLLEA 124

NUDIX hydrolase superfamily; 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 446751820   7 VVGAVIFNENNEVLCALRSPTmTLPNYWEFPGGKIKNGEEPQVALVREIKEELGCSITVDEK--VEEIEYEYETIIVHLT 84
Cdd:cd02883    2 AVGAVVFDDEGRVLLVRRSDG-PGPGGWELPGGGVEPGETPEEAAVREVREETGLDVEVLRLlgVYEFPDPDEGRHVVVL 80

                         90       100
                 ....*....|....*....|....*
gi 446751820  85 TYKAQILEGIPKAL---EHTELKWV 106
Cdd:cd02883   81 VFLARVVGGEPPPLddeEISEVRWV 105

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 446751820   7 VVGAVIFNENNEVLCALRSPT-MTLPNYWEF-PGGKIKNGEEPQVALVREIKEELGCSITVDE 67
Cdd:cd04693   31 VVHVWIFNSDGEILIQQRSPDkKGFPGMWEAsTGGSVLAGETSLEAAIRELKEELGIDLDADE 93

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 446751820   7 VVGAVIFNENNEVLCAlRSPTMTlpnYWEFPGGKIKNGEEPQVALVREIKEELGCSITVDE-----KVEEIEYEYETIIV 81
Cdd:cd04690    2 VKAAVIIIKDGRLLLV-RKRGTD---AFYLPGGKREPGETPLQALVRELKEELGLDLDPDSlrflgTFEAPAANEPGTTV 77

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*..
gi 446751820  82 HLTTYKAQIlEGIPKAL-EHTELKWVRVKDLNNLYWAPADIPTVESL 127
Cdd:cd04690   78 RMTCFTADY-DGEPQPAaEIEELRWLDPADPDDDRLAPLLREIVLPL 123

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 446751820   8 VGAVIFNeNNEVLCALRSPTMtlPNYWEFPGGKIKNGEEPQVALVREIKEELGCSITVDEKVEEIE-YEYETIIVHLTTY 86
Cdd:cd04699    5 VKGVIFD-NGRVLLLRRSRAG--AGEWELPGGRLEPGESPEEALKREVKEETGLDVSVGELLDTWTfELDPDKGVFIVTY 81

                         90       100
                 ....*....|....*....|....*....
gi 446751820  87 KAQILEGIPKAL-EHTELKWVRVKDLNNL 114
Cdd:cd04699   82 LCRLVGGEVTLSdEHEEYEWVTPEELAEL 110

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        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 446751820    2 KRRISVVGAVIFNENNEVLCALRSPTMTLPNYWEFPGGKIKNGEEPQVALVREIKEELGCSITVDEKVEEIEYEYETIIV 81
Cdd:TIGR00586   1 KKLQQIAVGIIRNENGEIIITRRADGHMFAKLLEFPGGKEEGGETPEQAVVRELEEEIGIPQHFSEFEKLEYEFYPRHIT 80

                          90       100       110
                  ....*....|....*....|....*....|....*....
gi 446751820   82 HLTTYKAQILEGIPKALEHTELKWVRVKDLNNLYWAPAD 120
Cdd:TIGR00586  81 LWFWLLERWEGGPPGKEGQPEEWWVLVGLLADDFFPAAN 119

NUDIX domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 446751820   10 AVIFNENNEVLCALRSPTMTLPNYWEFPGGKIKNGEEPQVALVReiKEELGCSITVDEKVeeieyeyetIIVH------- 82
Cdd:pfam14815   3 LVIRNGDGRVLLRKRPEKGLLGGLWEFPGGKVEPGETLEEALAR--LEELGIEVEVLEPG---------TVKHvfthfrl 71

                          90       100       110
                  ....*....|....*....|....*....|...
gi 446751820   83 -LTTYKAQILEGIPkaLEHTELKWVRVKDLNNL 114
Cdd:pfam14815  72 tLHVYLVREVEGEE--EPQQELRWVTPEELDKY 102

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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 446751820   2 KRRISVVgAVIFNENNEVLCalrspTMTLPNYWEFPGGKIKNGEEPQVALVREIKEELGCSITVDEKV 69
Cdd:cd04684   13 KDRPGAY-AVIFNDEGKVLL-----VQTPNGGYFLPGGGIEPGETPEEALHREVLEETGWEIEIGEFL 74

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 446751820   8 VGAVIFNENNEVLCA-LRSPTmtlPNYWEFPGGKIKNGEEPQVALVREIKEELGCSITVDEKVEEIEYEYETIIVHLT-- 84
Cdd:cd04679    5 CGAAILDDGRLLLVLrLRAPE---AGHWGLPGGKVDWLETVEDAVRREILEELGLEIELTRLLCVVDQIDAADGEHWVap 81

                         90       100       110
                 ....*....|....*....|....*....|
gi 446751820  85 TYKAQILEGIPKALE---HTELKWVRVKDL 111
Cdd:cd04679   82 VYLAEIFSGEPRLMEpekHGGIGWFALDAL 111

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 446751820   8 VGAVIFNENNeVLCAlRSPTmtlPNYWEFPGGKIKNGEEPQVALVREIKEELGCSITVDE 67
Cdd:cd04688    5 VAAIIIRDGK-VLLA-RGED---DDYYRLPGGRVEFGETSEDALVREFKEELGVEVEVVR 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
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 446751820   5 ISVVGAVIFNENNEVLCaLRSPTMTlpNYWEFPGGKIKNGEEPQVALVREIKEELGCSIT 64
Cdd:cd18874    2 EPTVGALIFNPDGKVLL-VRSHKWN--DLYGIPGGKVEWGETLEEALKREVKEETGLDIT 58

nucleoside triphosphatase NudI; Provisional

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 446751820   1 MKRRIsVVGAVIFNENNEVLCALRSPTMTLPNYWEFPGGKIKNGEEPQVALVREIKEELGCSITVDE 67
Cdd:PRK15472   1 MRQRT-IVCPLIQNDGAYLLCKMADDRGVFPGQWALSGGGVEPGERIEEALRREIREELGEQLLLTE 66

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 446751820  11 VIFNENNEVLCALRSPTMTLPNYWEFPGGKIKNGEEPQVALVREIKEELGcsITVDEkveeiEYEYETIIVHLTT----- 85
Cdd:cd04683    5 LLLVRGDEVLLLRRANTGYDDGWWHLPAGHVEAGETVRAAAVREAKEELG--VEIDP-----EDLRLVHTMHRRSdggre 77

                         90       100       110
                 ....*....|....*....|....*....|....
gi 446751820  86 -----YKAQILEGIPKALE---HTELKWVRVKDL 111
Cdd:cd04683   78 ridffFRATRWSGEPRNREpdkCAELRWFPLDAL 111

MutT homolog 2; MutT Homolog 2 (MTH2; EC 3.6.1.9), also known as NUDIX (nucleoside diphosphate-linked moiety X)) motif 15/Nudt15, may catalyze the hydrolysis of nucleoside diphosphates, triphosphates including dGTP, dTTP, dCTP, their oxidized forms like 8-oxo-dGTP, and prodrug thiopurine derivatives 6-thio-dGTP and 6-thio-GTP. MTH2 may also play a role in DNA synthesis and cell cycle progression by stabilizing PCNA. 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 446751820   8 VGAVIFNENNEVLCALRSpTMTLPNYWEFPGGKIKNGEEPQVALVREIKEELGCSIT 64
Cdd:cd04678    5 VGVIVLNDDGKVLLGRRK-GSHGAGTWALPGGHLEFGESFEECAAREVLEETGLEIR 60

DR1025 and similar proteins; DR1025 from Deinococcus radiodurans, a member of the NUDIX hydrolase superfamily, show nucleoside triphosphatase and dinucleoside polyphosphate pyrophosphatase activities. Like other enzymes belonging to this superfamily, it requires a divalent cation, in this case Mg2+, for its activity. It also contains a highly conserved 23-residue NUDIX motif (GX5EX7REUXEEXGU, where U = I, L or V), which functions as a metal binding and catalytic site. In general, 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 446751820   9 GAVIFNENNEVLCALR---SPTMTLPNYWEFPGGKIKNGEEPQVALVREIKEELG 60
Cdd:cd04700   17 GVVLLNERGDILLVQEkgiSGHPEKAGLWHIPSGAVEDGENPQDAAVREACEETG 71

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 446751820   2 KRRISVVGAV--IFNENNEVLCALRSPTmtlpNYWEFPGGKIKNGEEPQVALVREIKEELG 60
Cdd:cd04677    7 HRPLILVGAAviILNEQGRILLQKRTDT----GDWGLPGGAMELGESLEETARREVFEETG 63

GDP-mannose glycosyl hydrolase; GDP-mannose glycosyl hydrolase, also known as GDP-mannose mannosyl hydrolase/GDPMH, is a member of the NUDIX hydrolase superfamily. This class of enzymes is unique from other members of the superfamily in two aspects. First, it contains a modified NUDIX signature sequence. The slight changes to the conserved sequence motif, GX5EX7REUXEEXGU, where U = I, L or V), are believed to contribute to the removal of all magnesium binding sites but one, retaining only the metal site that coordinates the pyrophosphate of the substrate. Secondly, it is not a pyrophosphatase that substitutes at a phosphorus; instead, it hydrolyzes nucleotide sugars such as GDP-mannose to GDP and mannose, cleaving the phosphoglycosyl bond by substituting at a carbon position. GDP-mannose provides mannosyl components for cell wall synthesis and is required for the synthesis of other glycosyl donors (such as GDP-fucose and colitose) for the cell wall. The importance of GDP-sugar hydrolase activities is thus closely related to the regulation of cell wall biosynthesis. Enzymes in this family are believed to regulate the concentration of GDP-mannose and GDP-glucose in the bacterial cell wall.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 446751820  11 VIFNENNEVLCALR--SPTMtlpNYWEFPGGKIKNGEEPQVALVREIKEELGCSITVDE 67
Cdd:cd03430   21 IIRNEDGEILLGKRnnRPAQ---GYWFVPGGRILKNETLDDAFKRIAREELGLEVTINA 76

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 446751820  10 AVIFNENNEV-LCALRSPTMTLPNYWEFPGGKIKNGEEPQVALVREIKEELGcsITVDEKV 69
Cdd:cd04685    5 VLLLDPDGRVlLFRFHDPDDPGRSWWFTPGGGVEPGESPEQAAVRELREETG--LRLEPDD 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        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 446751820  18 EVLCALRSPTMTLPNYWEFPGGKIKNGEEPQVALVREIKEElgCSITVDEKVEEIEYEYETIIVHLTTYKAQI---LEGI 94
Cdd:cd18877   33 HVLLQHRAWWTHQGGTWALPGGARDSGETPEAAALRETEEE--TGLDADTLRVVGTHVDDHGGWSYTTVLASApepLPVR 110

                         90       100
                 ....*....|....*....|
gi 446751820  95 PKALEHTELKWVRVKDLNNL 114
Cdd:cd18877  111 PANEESVELRWVPLDEVESL 130

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 446751820  34 WEFPGGKIKNGEEPQVALVREIKEELG 60
Cdd:cd04667   23 WLLPGGKIEPGESPLEAAIRELKEETG 49

ADP-ribose pyrophosphatase, UDP-glucose pyrophosphatase, and similar proteins; ADP-ribose pyrophosphatase (ADPRase) ( 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. UDP-glucose pyrophosphatase (UGPPase) (EC 3.6.1.45; also known as nucleoside diphosphate-linked moiety X)) motif 14; Nudt14) hydrolyzes the pyrophosphate of the nucleoside diphosphate sugar to generate glucose-1-P and UMP. In mammals, UDP-glucose is the glucosyl donor for the synthesis of the storage polysaccharide glycogen. UGPPase, as a regulator of UDP-glucose, could play a regulatory role, but it has been shown to prefer ADP-ribose over UDP-glucose. Like other members of the NUDIX hydrolase superfamily, it requires a divalent cation, such as Mg2+, for its activity. 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.

                         10        20
                 ....*....|....*....|....*..
gi 446751820  34 WEFPGGKIKNGEEPQVALVREIKEELG 60
Cdd:cd03424   31 LELPAGKIDPGEDPEEAARRELEEETG 57

diadenosine tetraphosphate; Diadenosine tetraphosphate (Ap4A; EC 3.6.1.17), also called NUDIX (nucleoside diphosphate-linked moiety X)) motif 2/Nudt2, is a member of the NUDIX hydrolase superfamily. Ap4A hydrolases are well represented in a variety of prokaryotic and eukaryotic organisms. Phylogenetic analysis reveals two distinct subgroups where plant enzymes fall into one subfamily and fungi/animals/archaea enzymes, represented by this subfamily, fall into another. Bacterial enzymes are found in both subfamilies. Ap4A is a potential by-product of aminoacyl tRNA synthesis, and accumulation of Ap4A has been implicated in a range of biological events, such as DNA replication, cellular differentiation, heat shock, metabolic stress, and apoptosis. Ap4A hydrolase cleaves Ap4A asymmetrically into ATP and AMP. It is important in the invasive properties of bacteria and thus presents a potential target for inhibition of such invasive bacteria. Besides the signature NUDIX motif (G[X5]E[X7]REUXEEXGU, where U is Ile, Leu, or Val) that functions as a metal binding and catalytic site, and a required divalent cation, Ap4A hydrolase is structurally similar to the other members of the NUDIX hydrolase superfamily with some degree of variation. Several regions in the sequences are poorly defined and substrate and metal binding sites are only predicted based on kinetic studies.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 446751820   9 GAVIFNENNEVLCAL--RSPTmtlPNYWEFPGGKIKNGEEPQVALVREIKEELGCSITVDEK 68
Cdd:cd03428    6 GAIIYRRDNGEIEFLllQHSY---GGHWDFPKGHVEPGESELETALRETKEETGLTVDDLPP 64

MutT homolog-1 (MTH1); MutT homolog-1 (MTH1; EC 3.6.1.- ), also called 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
                 ....*....|....*....|....*....|....*.
gi 446751820  32 NYWEFPGGKIKNGEEPQVALVREIKEElgCSITVDE 67
Cdd:cd03427   27 GKWNGFGGKVEPGETIEEAAVRELEEE--AGLTATE 60

diadenosine hexaphosphate (Ap6A) hydrolase; Diadenosine hexaphosphate (Ap6A) hydrolase is a member of the NUDIX hydrolase superfamily. Ap6A hydrolase specifically hydrolyzes diadenosine polyphosphates, but not ATP or diadenosine triphosphate, and it generates ATP as the product. Ap6A, the most preferred substrate, hydrolyzes to produce two ATP molecules, which is a novel hydrolysis mode for Ap6A. These results indicate that Ap6A hydrolase is a diadenosine polyphosphate hydrolase. It requires the presence of a divalent cation, such as Mn2+, Mg2+, Zn2+, and Co2+, for activity. Members of the NUDIX hydrolase superfamily 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.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 446751820   9 GAVIFNENN---EVLCALRsptmtlPNY--WEFPGGKIKNGEEPQVALVREIKEELGCSITV 65
Cdd:cd03673    5 GGVVWRGRGgggEVLLIHR------PRYddWSLPKGKLEPGETPEEAAVREVEEETGLRVRL 60

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 446751820  33 YWEFPGGKIKNGEEPQVALVREIKEELGCSITV 65
Cdd:cd04669   25 YYVFPGGGIEPGETPEEAALREAVEELGLDVAV 57

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
                 ....*....|....*....|....*....|.
gi 446751820  37 PGGKIKNGEEPQVALVREIKEELGCSITVDE 67
Cdd:cd18883   27 PGGHIEIGESAEIALVRELREELGLSCKVGR 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        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 446751820   8 VGAVIFNENNEVLCaLRSptmTLPNYWEFPGGKIKNGEEPQVALVREIKEELGCSITVDEKV 69
Cdd:cd04680    3 VRAIVLDDAGRVLL-VRH---TYVPGWYLPGGGVDKGETAEEAARRELREEAGVVLTGPPRL 60

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 446751820  34 WEFPGGKIKNGEEPQVALVREIKEELG 60
Cdd:cd18888   35 IEFPAGLVDPGESPEQAALRELKEETG 61

NUDIX family Ndx2; NUDIX family protein Ndx2 found in Thermus thermophilus has ADP-ribose pyrophosphatase (ADPRase) as well as flavin adenine dinucleotide (FAD) activity. 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.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 446751820  33 YWEFPGGKIKNGEEPQVALVREIKEELG 60
Cdd:cd24161   31 SWEIPAGGWPEGEDPEEAARRELREETG 58

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 446751820   7 VVGAVIFNE-NNEVLcalrsptMTLPNY---WEFPGGKIKNGEEPQVALVREIKEELGCSITV 65
Cdd:cd03674    3 TASAFVVNPdRGKVL-------LVHHRKlgrWLQPGGHVEPDEDPLEAALREAREETGLDVEL 58

nucleoside diphosphate-linked moiety X)) motif 16; U8 SnoRNA-decapping enzyme, also known as NUDIX (nucleoside diphosphate-linked moiety X)) motif 16/Nudt16, is encoded by the human NUDT16 gene and a RNA-binding and decapping enzyme that catalyzes the cleavage of the cap structure of snoRNAs and mRNAs in a metal-dependent manner. 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
                 ....*....|....*....|....*....|
gi 446751820  36 FPGGKIKNGEEPQVALVREIKEELGCSITV 65
Cdd:cd18869   40 FPGGFVDTGESLEEGLNRELREELGLAHAV 69

NUDIX domain family found in Deinococcus radiodurans, and similar proteins; Deinococcus radiodurans protein DR_0079 is one of 21 NUDIX hydrolases that it encodes, and it has been observed to have a marked preference for cytosine ribonucleoside 5'-diphosphate (CDP) and cytosine ribonucleoside 5'-triphosphate (CTP), and for their corresponding deoxyribose nucleotides, dCDP and dCTP, to a lesser degree. 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        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 446751820   7 VVGAVIFNENNEVLCALRSPTMTL-PNYWEFP-GGKIKNGEEPQVALVREIKEELGCSIT 64
Cdd:cd24154    4 VVNAFLINSQGQLWIPRRTADKRIfPLALDMSvGGHVSSGETYEQAFVRELQEELNLDLD 63