Secretion of staphylocoagulase be Staphylococcus aureus: the role of a cell-bound intermediate

A cell-bound staphylocoagulase could be detected in chemostat cultures of Staphylococcus aureus 104 under magnesium-and oxygen-limited growth conditions. A distribution study revealed that 81% of the enzyme was membrane-bound and could be optimally released by Triton X-100. The remaining part was located in the periplasmic space and was released during protoplasting of organism. From inhibition studies with cerulenin, quinacrine, lincomycin an chloramphenicol, it was concluded that the cell-bound form was precursor in the secretion of extracellular staphylocoagulase. The involvement of a lipid intermediate/exoprotein-releasing protease system in the secretion of staphylocoagulase, and of exoproteins in general, is discussed.