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 (By similarity). GTP + H2O = GDP + H(+) + phosphate Belongs to the TRAFAC class dynamin-like GTPase superfamily. GB1/RHD3 GTPase family. GB1 subfamily.