Hydrolyzes ATP, and can also hydrolyze GTP with lower efficiency. Has lower affinity for GTP (Potential). Exhibits GTPase activity (By similarity). Confers sensitivity to salinity stress by suppressing the anti-oxidation enzymatic activities and increasing lipid peroxidation thus leading to the accumulation of reactive oxygen species (ROS) (PubMed:23550829). Acts as negative regulator of disease resistance against bacterial pathogen (PubMed:26912459). Activated by GAP1. Monomer (Potential). Interacts with CAR4/GAP1 (PubMed:23550829). Localized mainly in the cytosol under NaCl treatment, but translocates to the plasma membrane upon wounding. Increased tolerance to salinity stress. Plants over-expressing OLA1 exhibit enhanced susceptibility to the bacterial pathogen Pseudomonas syringae pv. tomato strain DC3000. Belongs to the TRAFAC class OBG-HflX-like GTPase superfamily. OBG GTPase family. YchF/OLA1 subfamily.