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ENZYME

ENZYME entry: EC 3.5.4.25

Accepted Name
GTP cyclohydrolase II
Alternative Name(s)
GTP 7,8-8,9-dihydrolase (diphosphate-forming)
GTP-8-formylhydrolase
guanosine triphosphate cyclohydrolase II
Reaction catalysed
GTP + 4 H2O <=> 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)-pyrimidine + formate + 3 H(+) + 2 phosphate
Comment(s)
  • The enzyme, found in prokaryotes and some eukaryotes, hydrolytically cleaves the C-N bond at positions 8 and 9 of GTP guanine, followed by a subsequent hydrolytic attack at the base, which liberates formate, and cleavage of the alpha-beta phosphodiester bond of the triphosphate to form diphosphate.
  • The enzyme continues with a slow cleavage of the diphosphate to form two phosphate ions.
  • The enzyme requires zinc and magnesium ions for the cleavage reactions at the GTP guanine and triphosphate sites, respectively.
  • It is one of the enzymes required for flavin biosynthesis in many bacterial species, lower eukaryotes, and plants. cf. EC 3.5.4.16, EC 3.5.4.29, and EC 3.5.4.39.
Cross-references
BRENDA3.5.4.25
EC2PDB3.5.4.25
ExplorEnz3.5.4.25
PRIAM enzyme-specific profiles3.5.4.25
KEGG Ligand Database for Enzyme Nomenclature3.5.4.25
IUBMB Enzyme Nomenclature3.5.4.25
IntEnz3.5.4.25
MEDLINEFind literature relating to 3.5.4.25
MetaCyc3.5.4.25
Rhea expert-curated reactions3.5.4.25
UniProtKB/Swiss-Prot
P50139, RIB1_PICGUQ9P7M9, RIB1_SCHPOP38066, RIB1_YEAST
P47924, RIBA1_ARATHQ6Z234, RIBA1_ORYSJQ0E079, RIBA2_ORYSJ
Q9FN89, RIBA3_ARATHQ6L506, RIBA3_ORYSJQ6F7N4, RIBA_ACIAD
B7GVX4, RIBA_ACIB3B7IA66, RIBA_ACIB5B2HZQ0, RIBA_ACIBC
B0VQB7, RIBA_ACIBSA3M9B0, RIBA_ACIBTB0V709, RIBA_ACIBY
A6VPG3, RIBA_ACTSZA0KJ91, RIBA_AERHHQ5E5L2, RIBA_ALIF1
B5FDS3, RIBA_ALIFMB6ENI2, RIBA_ALISLO29766, RIBA_ARCFU
P43525, RIBA_AZOBRC1DLI3, RIBA_AZOVDQ1LTG5, RIBA_BAUCH
Q7VR05, RIBA_BLOFLQ492N9, RIBA_BLOPBP57359, RIBA_BUCAI
Q8K9Q0, RIBA_BUCAPP59555, RIBA_BUCBPQ62BG3, RIBA_BURMA
A0RR75, RIBA_CAMFFA7I3X0, RIBA_CAMHCA8AG83, RIBA_CITK8
Q47WV5, RIBA_COLP3A7MMF7, RIBA_CROS8A7ZL97, RIBA_ECO24
B7UR85, RIBA_ECO27B7MLV3, RIBA_ECO45B7L4B3, RIBA_ECO55
P0A7I8, RIBA_ECO57B5YZQ8, RIBA_ECO5EB7NVQ1, RIBA_ECO7I
B7MUB9, RIBA_ECO81B7LY36, RIBA_ECO8AC4ZTX2, RIBA_ECOBW
B1XBM8, RIBA_ECODHA7ZZL5, RIBA_ECOHSQ0TI88, RIBA_ECOL5
Q8FHU5, RIBA_ECOL6B1ITH7, RIBA_ECOLCP0A7I7, RIBA_ECOLI
B7N493, RIBA_ECOLUB6I9Z2, RIBA_ECOSEB1LH12, RIBA_ECOSM
A4WAY6, RIBA_ENT38B7LS01, RIBA_ESCF3Q4QNX8, RIBA_HAEI8
A5UAU5, RIBA_HAEIEA5UG14, RIBA_HAEIGP44571, RIBA_HAEIN
Q0I4A3, RIBA_HAES1Q2SA07, RIBA_HAHCHC4K8Q4, RIBA_HAMD5
Q17XC9, RIBA_HELAHQ7VK48, RIBA_HELHPB6JM32, RIBA_HELP2
Q1CT68, RIBA_HELPHQ9ZL42, RIBA_HELPJB2UT29, RIBA_HELPS
O08315, RIBA_HELPYB0UUP7, RIBA_HISS2B5XS13, RIBA_KLEP3
A6T7Y5, RIBA_KLEP7Q65SC0, RIBA_MANSMA6VWW9, RIBA_MARMS
Q5F7N6, RIBA_NEIG1A9LZD5, RIBA_NEIM0Q9JU99, RIBA_NEIMA
Q9JZ78, RIBA_NEIMBA1KU62, RIBA_NEIMFP57863, RIBA_PASMU
Q6D5U5, RIBA_PECASP51618, RIBA_PHOPOQ6L1J7, RIBA_PICTO
B4EW08, RIBA_PROMHA6V055, RIBA_PSEA7B7V7R1, RIBA_PSEA8
Q02SL4, RIBA_PSEABQ9HWY1, RIBA_PSEAEQ1IFL5, RIBA_PSEE4
C3K2R5, RIBA_PSEFSA5VXW5, RIBA_PSEP1B0KL75, RIBA_PSEPG
Q88QH1, RIBA_PSEPKB1J3G0, RIBA_PSEPWQ889Q3, RIBA_PSESM
A1SSA8, RIBA_PSYINQ21F24, RIBA_SACD2Q57NU9, RIBA_SALCH
Q5PCY8, RIBA_SALPAP66031, RIBA_SALTIP66030, RIBA_SALTY
A1S528, RIBA_SHEAMB8EF62, RIBA_SHEB2A3D367, RIBA_SHEB5
A6WLV9, RIBA_SHEB8A9KXC4, RIBA_SHEB9Q12P94, RIBA_SHEDO
Q080N2, RIBA_SHEFNB0TL40, RIBA_SHEHHA3QFR4, RIBA_SHELP
Q8EDD1, RIBA_SHEONA8H5U9, RIBA_SHEPAA4Y5N5, RIBA_SHEPC
B8CQ07, RIBA_SHEPWA0KYF8, RIBA_SHESAA8FTP1, RIBA_SHESH
Q0HHF8, RIBA_SHESMQ0HTR2, RIBA_SHESRA1RL35, RIBA_SHESW
B1KLM0, RIBA_SHEWMB2U0G9, RIBA_SHIB3Q31ZX1, RIBA_SHIBS
Q32GQ6, RIBA_SHIDSQ0T5C0, RIBA_SHIF8P0A7I9, RIBA_SHIFL
Q3Z127, RIBA_SHISSO88011, RIBA_STRCOO68248, RIBA_SULMU
C5BS80, RIBA_TERTTQ97B83, RIBA_THEVOC4LE64, RIBA_TOLAT
Q9KSJ3, RIBA_VIBCHQ87NE7, RIBA_VIBPAQ8DAG7, RIBA_VIBVU
Q8D2J0, RIBA_WIGBRQ9PBZ3, RIBA_XYLFAQ87D69, RIBA_XYLFT
Q8ZEF0, RIBA_YERPEQ66AI6, RIBA_YERPSA3MZA2, RIBBA_ACTP2
B3H0P8, RIBBA_ACTP7B0BTN8, RIBBA_ACTPJP50855, RIBBA_ACTPL
Q5WH08, RIBBA_ALKCKO66679, RIBBA_AQUAEC3P7P7, RIBBA_BACAA
C3LIX7, RIBBA_BACACA0RIB3, RIBBA_BACAHP51695, RIBBA_BACAM
Q81MB6, RIBBA_BACANB7JLW6, RIBBA_BACC0Q731I5, RIBBA_BACC1
B7IWM5, RIBBA_BACC2C1EQY5, RIBBA_BACC3B7HAY4, RIBBA_BACC4
B7HNM8, RIBBA_BACC7A7GSD5, RIBBA_BACCNB9IWX4, RIBBA_BACCQ
Q818X6, RIBBA_BACCRQ635H0, RIBBA_BACCZQ5LHT1, RIBBA_BACFN
Q64YT3, RIBBA_BACFRQ6HE54, RIBBA_BACHKA9VG50, RIBBA_BACMK
P17620, RIBBA_BACSUQ8A528, RIBBA_BACTNA7Z675, RIBBA_BACVZ
C0ZKW2, RIBBA_BREBNQ3B2I6, RIBBA_CHLL3Q9PLJ5, RIBBA_CHLMU
A4SFY4, RIBBA_CHLPMQ9Z734, RIBBA_CHLPNO84736, RIBBA_CHLTR
A0Q3H7, RIBBA_CLONNO24752, RIBBA_CORAMA4QEG9, RIBBA_CORGB
Q8NQ52, RIBBA_CORGLQ11WK6, RIBBA_CYTH3B1H0I0, RIBBA_ENDTX
C5D3N0, RIBBA_GEOSWA0QI09, RIBBA_MYCA1B1MCA4, RIBBA_MYCA9
P0A5V1, RIBBA_MYCBOA1KIK4, RIBBA_MYCBPC1AN60, RIBBA_MYCBT
A4TC13, RIBBA_MYCGIB2HP67, RIBBA_MYCMMQ741F1, RIBBA_MYCPA
A5U2B7, RIBBA_MYCTAP9WHF0, RIBBA_MYCTOP9WHF1, RIBBA_MYCTU
A0PPL6, RIBBA_MYCUAA1T8K1, RIBBA_MYCVPQ5YTP3, RIBBA_NOCFA
A6LHN0, RIBBA_PARD8B4SE30, RIBBA_PELPBA6KWQ7, RIBBA_PHOV8
B2RIG7, RIBBA_PORG3Q7MWK9, RIBBA_PORGIB4S5Y8, RIBBA_PROA2
C0ZZE5, RIBBA_RHOE4Q0S0K2, RIBBA_RHOJRA8LY38, RIBBA_SALAI
A4X639, RIBBA_SALTOQ5HF07, RIBBA_STAACQ99TA0, RIBBA_STAAM
Q7A511, RIBBA_STAANQ6GFT5, RIBBA_STAARQ6G8G1, RIBBA_STAAS
Q8NW14, RIBBA_STAAWQ5HNE3, RIBBA_STAEQQ8CNU2, RIBBA_STAES
Q4L7B1, RIBBA_STAHJQ49YJ7, RIBBA_STAS1Q0AXM5, RIBBA_SYNWW
P74104, RIBBA_SYNY3Q9X2E6, RIBBA_THEMAB0KAI2, RIBBA_THEP3
B0K0Y9, RIBBA_THEPXQ7MGG3, RIBXA_VIBVY

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All UniProtKB/Swiss-Prot entries referenced in this entry, with possibility to download in different formats, align etc.
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 3.5.4.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 3.5.-.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 3.-.-.-