Part of the accessory SecA2/SecY2 system specifically required to export GspB, a serine-rich repeat cell wall protein encoded upstream in the same operon. ATP + H2O + cellular proteinSide 1 = ADP + phosphate + cellular proteinSide 2. Monomer and homodimer (Potential). Part of the accessory SecA2/SecY2 protein translocation apparatus required to export cell wall protein GspB. Distribution is 50-50. Loss of export of cell wall protein GspB; glycosylated GspB accumulates in the cytoplasm. Belongs to the SecA family.