May be involved in the GO system responsible for removing an oxidatively damaged form of guanine (7,8-dihydro-8-oxoguanine, 8-oxo-dGTP) from DNA and the nucleotide pool. 8-oxo-dGTP is inserted opposite dA and dC residues of template DNA with almost equal efficiency thus leading to A.T to G.C transversions. MutT specifically degrades 8-oxo-dGTP to the monophosphate (By similarity). 8-oxo-dGTP + H2O = 8-oxo-dGMP + diphosphate + H(+) No visible phenotype. There are 4 mutT paralogs in M.tuberculosis; the exact function of each is unknown. Belongs to the Nudix hydrolase family.