Figure 2
Comparison of three different promoters for gene expression and GABA production in C. glutamicum . (A) SDS-PAGE analysis of mutant GAD gene expression under the three synthetic promoters (PL26, PI16, or PH36). Lane M, protein size markers (kDa). Lanes 1 and 2, C. glutamicum harboring pCES208.Lanes 3 and 4, C. glutamicum harboring pLGmut. Lanes 5 and 6, C. glutamicum harboring pIGmut. Lanes 7 and 8, C. glutamicum harboring pHGmut. Lanes 1, 3, 5, and 7, total protein fractions. Lanes 2, 4, 6, and 8, soluble protein fractions. (B) Time course of GABA concentration during flask cultivation of C. glutamicum. Triangle, square, circle and diamond symbols indicate C. glutamicum harboring pLGmut, pIGmut, pHGmut and pHGwt respectively. Each point represents the average of three independent experiments.