FIG 4.

A unique SNP in saeR from Newman D2C renders the protein product nonfunctional. (A) Western blot demonstrating that a ΔsaeQRS mutant complemented with saeQRS from either Newman D2C or NYU Newman produced SaeR protein. SaeR produced from a plasmid and purified SaeR served as positive controls; these proteins carried a histidine tag. (B) Only the saeQRS allele from NYU Newman was capable of restoring protein secretion in a complemented ΔsaeQRS mutant. (C) The Newman D2C saeQRS allele could not reconstitute hemolysis in a ΔsaeQRS mutant, while the NYU Newman saeQRS allele could restore hemolysis.