ATPase that binds to both the 70S ribosome and the 50S ribosomal subunit in a nucleotide-independent manner (By similarity). Does not hydrolyze GTP. Composed of 3 distinct structural domains: the N-terminal domain, which has a mononucleotide binding fold typical for the P-loop NTPases, followed by a pronounced alpha-helical coiled coil domain and the C-terminal domain, which may be involved in RNA binding. Belongs to the TRAFAC class OBG-HflX-like GTPase superfamily. OBG GTPase family. YchF/OLA1 subfamily.