FIG. 4.

Two-dimensional electrophoresis of bacterial exoproteins reveals significantly altered protein profiles for ΔprsA2 mutants. Supernatants from the wild-type strain or ΔprsA1, ΔprsA2, or ΔprsA1 ΔprsA2 mutant strains were trichloroacetic acid (TCA) precipitated and subjected to two-dimensional SDS-PAGE, revealing a significantly altered protein profile for ΔprsA2 mutant supernatants (B) in comparison to wild-type supernatants (A). A ΔprsA1 mutant supernatant profile (C) closely resembled that of the wild type, while a ΔprsA1 ΔprsA2 mutant profile (D) was remarkably similar to the ΔprsA2 single mutant.