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. Part of the accessory SecA2/SecY2 protein translocation apparatus required to export cell wall protein GspB. No export of mature cell wall protein GspB, a small amount of unprocessed protein is exported to the cell wall while the rest accumulates intracellularly, probably in a glycosylated form. Cells bind less well to platelets.