Improved pFastBac™ donor plasmid vectors for higher protein production using the Bac-to-Bac® baculovirus expression vector system

5. Conclusions 
Since the pFastBac-M2 and pFastBac-Dual-M2 vectors have the same MCS as 
commercial pFastBac™1 and pFastBac™ Dual, researchers who are using these vectors for 
protein expression can simply transfer their genes of interest into the improved pFastBac-M2 and 
pFastBac-Dual-M2 vectors to achieve higher protein expression yields and reduce protein 
production costs. All other baculovirus vectors using the 50 bp 
polh 
promoter and SV40 pA can 
also be modified to include the 80 bp 
cis
element and to replace SV40 pA with the 
polh 
pA 
fragment for improved protein expression yields in High Five cells. 
Conflicts of Interest:
 
The authors declare no financial or commercial conflict of interest. 
Author Contributions: 
XWC, TAG and HS
 
planned experiments; TAG, HS, CMSK and RFD 
performed experiments; XWC, TAG and HS analyzed data; XWC and TAG wrote the paper
 
Acknowledgments 
The authors would like to thank Drs. Natasha Finley and Racheal Morgan-Kiss for 
providing the bacterial protein and filter, respectively, used in identifying the cytoplasmic 
crystals. Dr. Don Jarvis is credited with providing the virus for identification of the cytoplasmic 

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polyhedrin crystals and suggestions in the writing of this manuscript. We also thank Dr. Susanne 
Wells for providing the HPV16 plasmid and Dr. Susan Hoffman for proofreading this 
manuscript. This work was supported by the US Department of Agriculture (US-Egypt Science 
and Technology Joint Fund project no. 58-3148-7-164) and the Miami University 
Interdisciplinary Research Round Table Fund Project.
 
 

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