FIG. 2.

Affinity immunoblot analysis demonstrates the binding of GST-PcrH to Thio-PopD and Thio-PopB. The protein samples from E. coli expressing Thio-tagged fusion proteins were loaded onto a sodium dodecyl sulfate-4 to 12% bis-Tris polyacrylamide gel electrophoresis gel for electrophoresis. Proteins were then blotted onto a nitrocellulose membrane for subsequent affinity immunoblot analysis. Affinity immunoblotting demonstrates the interaction between GST-PcrH and Thio-PopD. The blotted membrane was incubated in a solution with purified recombinant GST-PcrH. After the membrane was washed several times, immunostaining against the GST tag was performed with anti-GST antibody conjugated with horseradish peroxidase and chemiluminescent substrate. The intense bands demonstrating the interaction with GST-PcrH were recognized in Thio-tagged PopB and PopD lanes (arrowheads). IgG, immunoglobulin G.