FIG 5.

Effects of dacA and dacB deletion on extracellular recombinant green fluorescent protein (GFP) secretion. (A) Extracellular specific fluorescence intensity. AU, arbitrary units. Asterisks indicate a significant difference compared with control cells (none, P > 0.05; *, P < 0.05; and **, P < 0.01). (B) Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis. M, standard molecular weight markers; arrow, GFP; control, E. coli BL21-pETDUET-gfp (extracellular); ΔdacA, BL21 ΔdacA pETDuet-gfp; ΔdacB, BL21 ΔdacB pETDuet-gfp; ΔdacA ΔdacB, BL21 ΔdacA ΔdacB pETDuet-gfp; P-control, E. coli BL21-pETDuet-gfp (positive control, intracellular); N-control, E. coli BL21-pETDuet (negative control, intracellular).