IUBMB Enzyme Nomenclature


Accepted name: inosine/xanthosine triphosphatase

Reaction: (1) inosine 5'-triphosphate + H2O = inosine 5'-diphosphate + phosphate
(2) xanthosine 5'-triphosphate + H2O = xanthosine 5'-diphosphate + phosphate

Glossary: inosine 5'-triphosphate = ITP
xanthosine 5'-triphosphate = XTP

Other name(s): yjjX (gene name)

Systematic name: inosine/xanthosine 5'-triphosphate phosphohydrolase

Comments: The enzyme, characterized from the bacterium Escherichia coli, preferentially hydrolyses inosine triphosphate and xanthosine triphosphate, which are formed by oxidative deamination damage. By hydrolysing these damaged nucleotides, the enzyme prevents their incorporation into RNA.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:


1. Zheng, J., Singh, V.K. and Jia, Z. Identification of an ITPase/XTPase in Escherichia coli by structural and biochemical analysis. Structure 13 (2005) 1511-1520. [PMID: 16216582]

[EC created 2020]

Return to EC 3.6.1 home page
Return to EC 3.6 home page
Return to EC 3 home page
Return to Enzymes home page
Return to IUBMB Biochemical Nomenclature home page