Translocase is a general term for a protein that assists in moving another molecule, usually across a cell membrane. These enzymes catalyze the movement of ions or molecules across membranes or their separation within membranes. The reaction is designated as a transfer from “side 1” to “side 2” because the designations “in” and “out”, which had previously been used, can be ambiguous.[1] Translocases are the most common secretion system in Gram positive bacteria.
It is also a historical term for the protein now called elongation factor G, due to its function in moving the transfer RNA (tRNA) and messenger RNA (mRNA) through the ribosome.