Peptidoglycan monomers are synthesized in the cytosol of the bacterium where they attach to a membrane carrier molecule called bactoprenol.

The bactoprenols transport the peptidoglycan monomers across the cytoplasmic membrane and helps insert them into the growing peptidoglycan chains.

After the bactoprenol inserts the peptidoglycan monomer it is transporting, it loses a phosphate group on its way back to the cytoplasmic membrane to be recycled and pick up another monomer.