Involved in targeting and insertion of nascent membrane proteins into the cytoplasmic membrane. Acts as a receptor for the complex formed by the signal recognition particle (SRP) and the ribosome-nascent chain (RNC). Part of the signal recognition particle protein translocation system, which is composed of SRP and FtsY. Doubling time increases for growth under nonstress conditions, unable to initiate growth at pH 5.0 and under 3.5% NaCl salt stress. Double deletions of FtsY and Ffh, or FtsY and YidC2 are barely able to grow in the absence of stress. Belongs to the GTP-binding SRP family. FtsY subfamily.