Involved in the regulation of bacterial cell survival under conditions of nutritional stress. Regulates the type II MazE-MazF toxin-antitoxin (TA) system which mediates programmed cell death (PCD). This is achieved by lowering the cellular concentration of (p)ppGpp produced by RelA under amino acid starvation, thus protecting the cell from the toxicity of MazF. Reduction of (p)ppGpp can be achieved by direct degradation of (p)ppGpp or by degradation of NTPs, which are substrates for (p)ppGpp synthesis by RelA. ATP + H2O = AMP + diphosphate + H(+) Inhibited by the MazE-MazF complex. Homodimer. Interacts with Era. Part of the relA-mazE-mazF-mazG operon, there is also a second mazE-mazF specific promoter which is negatively autoregulated. Belongs to the nucleoside triphosphate pyrophosphohydrolase family.