In vitro GST pulldown assays for SecA2, Asp1, and Asp3 interactions by S. agalactiae. (A) Equal amounts of purified GST, GST-Asp3, and GST-SecA2 bound to glutathione-Sepharose 4B beads were incubated with in vitro-translated c-Myc-Asp1. (B) Equal amounts of purified GST, GST-Asp1, and GST-SecA2 bound to glutathione-Sepharose 4B beads were incubated with in vitro-translated c-Myc-Asp3. (C) Equal amounts of purified GST, GST-Asp1, and GST-Asp3 bound to glutathione-Sepharose 4B beads were incubated with in vitro-translated c-Myc-SecA2. The pull-down protein complexes were analyzed by Western blotting using anti-c-Myc monoclonal antibody. Inputs represent the in vitro-translated protein products.