Fig. 2
From: Construction and development of an auto-regulatory gene expression system in Bacillus subtilis
Identification of the expression level and patterns of GFP in recombinant B. subtilis 168. a The fluorescence intensity of GFP (solid rectangle) and cell growth (solid cycle) under the control of wild-type PsrfA were monitored in recombinant B. subtilis 168 during cultivation in TB medium. b SDS-PAGE analysis for the expression of GFP in B. subtilis 168 harboring pBSG03 with PsrfA, which was cultivated in TB medium, showed the expression pattern. Samples were collected periodically at different time points, and total proteins of 30 μg were loaded onto the gel. c The impact of the medium on the expression level of GFP in B. subtilis 168 harboring pBSG03 (BSG101). The expression level of GFP under the control of PsrfA was determined by the total fluorescence intensity at OD600 (denoted as Au/OD600). The recombinant strain was cultivated in TB, MM, IMM and LB medium. All of the data were collected in triplicate and were presented as the mean ± SD. d Comparison of the expression patterns and levels controlled by PsfrA and PHpaII. B. subtilis 168 harboring pBSG03 (BSG101) and pBSG04 containing the PHpaII promoter (BSG102) were cultivated in LB medium for 40 h. The fluorescence intensity and cell growth for each of the recombinant strains were examined by periodic sampling throughout cultivation. The cell density of BSG101 (solid cycle) and BSG102 (open cycle) was monitored by measuring the OD600. The fluorescence intensity of BSG101 (solid rectangle) and BSG102 (open rectangle) was monitored throughout the process at corresponding time points