FIG 6.
Expression of GFP fused to the AmyE Sec signal peptide in B. subtilis. (A) Secretion of total GFP. The indicated strains in a Δ7 3610 background were grown overnight in HPDM supplemented with 1 mM IPTG. The next day, the cells were washed and resuspended in LPDM supplemented with 1 mM IPTG. At the indicated time points, the cells were lysed and the medium was precipitated with TCA. The cell lysates and precipitated medium were examined by Western blot probing with α-GFP, α-PhoD, and α-SigA antibodies. Migration of PhoDSP-GFP and SigA bands is indicated to the left of each blot. The migration of molecular mass standards is indicated to the right of each blot. In panel B, the SDS-PAGE gel was overloaded with sample and the blot was overexposed to visualize the AmyESP-GFP band.