The SecYEG-SecDF-YajC-YidC holo-translocon (HTL) protein secretase/insertase is a supercomplex required for protein secretion, insertion of proteins into membranes, and assembly of membrane protein complexes. While the SecYEG complex is essential for assembly of a number of proteins and complexes, the SecDF-YajC-YidC subcomplex facilitates these functions. Part of the SecDF-YidC-YajC translocase complex. The SecDF-YidC-YajC translocase forms a supercomplex with SecYEG, called the holo-translocon (HTL). Belongs to the YajC family.