Fig. 7.

Calcium binding by PilY1.1 is essential for TfcP function. (A) Assay for T4aPdM. Cells were grown in 1.0% CTT suspension culture and plated on 0.5% agar supplemented with 0.5% CTT and imaged after 24 h. The final concentration of added CaCl₂ is indicated. (Scale bar, 1 mm.) (B) Accumulation of PilY1.1 variants. Cells were grown in 1.0% CTT suspension culture without or with 1.0 mM CaCl₂, total cell extract isolated and analyzed by immunoblot as in Fig. 3B. (C) Accumulation of TfcP-FLAG and PilY1.1 in the presence of BAPTA. Cells were grown in 1.0% CTT in suspension, exposed to indicated concentrations of BAPTA for 16 h, and total cell extract was isolated and analyzed by immunoblot as in Fig. 3B.