Bac-to-Bac method delivers high baculovirus titers

Traditional baculovirus systems require purification and amplification of an initial low-titer viral supernatant. In contrast, the Bac-to-Bac Baculovirus Expression System is faster and easier because the technology relies on generation of recombinant baculovirus by site-specific transposition in E. coli rather than homologous recombination in insect cells, which often results in low titers.

Advantages of the Bac-to-Bac Expression Systems:

  • High titers up to 108 pfu enable large-scale protein expression
  • pFastBac vector contains polyhedrin promoter for high yields of recombinant protein
  • Reliable, rapid 5-minute blunt TOPO cloning saves time
  • N- and C-Terminal 6xHis tag for easy purification
  • TEV protease sites enable removal of N- or C-terminal tag yielding a native protein
  • Honeybee melittin (HBM) secretion signal tag for secreted protein expression

Download the Bac-to-Bac Expression Kit Handbook

Simplified cloning with quick, 5-minute TOPO cloning procedure

Our pFastBac TOPO Cloning vector recombines with the parent bacmid in DH10Bac E. coli competent cells to form an expression bacmid, which is then used for transfection into insect cells. After the very first transfection of the bacmid, you will produce high titers of pure recombinant baculovirus particles, saving weeks of precious time and enabling large-scale protein expression experiments.

Engineering the pFastBac vector with blunt TOPO Cloning technology simplifies your cloning reaction to a 5-minute bench-top reaction compared to tedious and time-consuming restriction enzyme cloning, which can take 2–3 days of work.

Bac-to-Bac HBM Secreted Expression System Kits

The Bac-to-Bac HBM TOPO Secreted Expression System enables secreted protein expression via the honeybee melittin (HBM) secretion signal. This expression system is ideal for the study of toxic proteins and glycoproteins (which require a secretion signal to be glycosylated). Also, glycoproteins secreted from baculoviruses can be easily de-glycosylated in vitro—an important feature for protein crystallization.

Multiple kit formats for your convenience

We offer two formats of our Bac-to-Bac Baculovirus Expression Systems. The Expression system format in the most complete kit available; these kits include pFastBac or pFastBac TOPO cloning vectors, specialized competent cells (DH10Bac E coli) for bacmid generation, and our ExpiFectamine Sf Transfection Reagent. If you simply need the pFastBac vector, we offer a Cloning kit format, which contain a pFastBac TOPO (C-His, N-His, or HBM) vector and competent cells for cloning in the gene of interest. We also offer cloning kits of our non-TOPO pFastBac vectors: non-tagged, N-His, or Dual expression vectors for cloning your gene of interest using standard restriction digestion and ligation.

ExpiSf Expression System: Superior protein yields and reproducibility with the proven Bac-to-Bac technology

The ExpiSf Expression System is a complete chemically defined baculovirus-insect cell protein expression system that delivers superior yields and consistent performance run after run using a fast, streamlined workflow. The superior performance of ExpiSf combined with Bac-to-Bac™ provides researchers with the simplicity of obtaining high-titer recombinant baculovirus in one simple step and go from transfection to protein harvest in 6-10 days.

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For Research Use Only. Not for use in diagnostic procedures.