FIG. 8.
Phenotypes of protein A cell wall sorting signal deletion mutants. Full-length protein A is found to be quantitatively anchored to the cell wall. Deletions of the charged tail, charged tail and hydrophobic domain, or the entire sorting signal result in the complete secretion of the polypeptide into the extracellular milieu. Deletion of the LPXTG motif of the C terminal abolishes the anchoring of the polypeptide to the cell wall. In the case of the protein A sorting signal, these mutant proteins are loosely associated with the cytoplasmic membrane.