Hydrolyzes GTP to GMP in 2 consecutive cleavage reactions (By similarity). Confers protection to several pathogens, including the bacterial pathogens Listeria monocytogenes and Mycobacterium bovis BCG as well as the protozoan pathogen Toxoplasma gondii (PubMed:21551061, PubMed:18025219). GTP + H2O = GDP + H(+) + phosphate By IFNG/IFN-gamma, IFNB1/IFN-beta, LPS and CpG oligodeoxynucleotides (PubMed:18025219). Up-regulated upon infection by T.gondii or L.monocytogenes (PubMed:18025219). Belongs to the TRAFAC class dynamin-like GTPase superfamily. GB1/RHD3 GTPase family. GB1 subfamily.