Abstract:

We employed Pvgb, oxygen-dependent promoter of VHb, for self-tuning regulation of green fluorescent protein (GFP) expression according to the natural transition of dissolved oxygen (DO) level during culture. A series of plasmid vectors have been created using promoter of varying size (Pvgb-L or Pvgb-S) to drive expression of GFP. We compared transcription and protein accumulation between each expression vector. Pvgb transcript level appears to parallel GFP protein accumulation. GFP expression in Escherichia coli strain was very largely affected by variation of aeration environment. Strong expression of xylose genes were also observed using low aeration in recombinant E. coli W3110(ΔpflB, ΔadhE) harboring pSK(Pvgb, xylA, xylB, talA, tktA).These vectors induced by Pvgb should be useful for overexpression of heterologous proteins and potentially metabolic engineering of E.coli strains.

Key words:  Pvgb; Green fluorescent protein; Escherichia coli; low oxygen; lactic acid