SecY protein

The SecY protein is the main transmembrane subunit of the eubacterial Sec or Type II secretory pathway and a protein-secreting ATPase complex, also known as a translocon.

Secretion of some proteins carrying a signal-peptide across the inner membrane in Gram-negative bacteria occurs via the preprotein translocase pathway. Proteins are produced in the cytoplasm as precursors, and require a chaperone subunit to direct them to the translocase component within the membrane. From there, the mature proteins are either targeted to the outer membrane, or remain as periplasmic proteins. The translocase protein subunits are encoded on the bacterial chromosome.