The enzyme, characterized from the bacterium Mycobacterium tuberculosis, catalyses the hydrolysis of both 8-oxo-GTP and 8-oxo-dGTP, thereby preventing transcriptional and translational errors caused by oxidative damage. The enzyme is highly specific. Unlike EC 3.6.1.55, 8-oxo-dGTP diphosphatase, it removes only a single phosphate group. The nucleoside diphosphate products are hydrolysed further by EC 3.6.1.58, 8-oxo-dGDP phosphatase.
Mycobacterium tuberculosis MutT1 (Rv2985) and ADPRase (Rv1700) proteins constitute a two-stage mechanism of 8-oxo-dGTP and 8-oxo-GTP detoxification and adenosine to cytidine mutation avoidance.