CpaA secretion is conserved among medically relevant Acinetobacter species. Whole cells (W) and supernatants (S) of A. baumannii (AB), Acinetobacter baylyi (AY), A. calcoaceticus (AC), A. pittii (AP), and A. nosocomialis (AN) strains were analyzed by Western blotting using anti-CpaA (green) and anti-RNA polymerase (red) antibodies. CpaA is detected in the supernatants of various AB, AP, and AN strains, all of which are recent clinical isolates. RNA polymerase was included as a lysis control.