Western blot analysis. Proteins in lysates from D39, D39:BCDΔ, D39:EHA-Cps2C, and the various mutants constructed as part of this study were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and analyzed by immunoblotting using anti-HA (to detect HA-Cps2C), anti-CpsD, or anti-phosphotyrosine (to detect Cps2D∼P).