Characterization of Recombinant Thermococcus kodakaraensis (KOD) DNA Polymerases Produced Using Silkworm-Baculovirus Expression Vector System

Abstract
The KOD DNA polymerase from Thermococcus kodakarensis (Tkod-Pol) has been preferred for PCR due to its rapid elongation rate, extreme thermostability and outstanding fidelity. Here in this study, we utilized silkworm-baculovirus expression vector system (silkworm-BEVS) to express the recombinant Tkod-Pol (rKOD) with N-terminal (rKOD-N) or C-terminal (rKOD-C) tandem fusion tags. By using BEVS, we produced functional rKODs with satisfactory yields, about 1.1 mg/larva for rKOD-N and 0.25 mg/larva for rKOD-C, respectively. Interestingly, we found that rKOD-C shows higher thermostability at 95 °C than that of rKOD-N, while that rKOD-N is significantly unstable after exposing to long period of heat-shock. We also assessed the polymerase activity as well as the fidelity of purified rKODs under various conditions. Compared with commercially available rKOD, which is expressed in E. coli expression system, rKOD-C exhibited almost the same PCR performance as the commercial rKOD did, while rKOD-N did lower performance. Taken together, our results suggested that silkworm-BEVS can be used to express and purify efficient rKOD in a commercial way.

Citation
Yamashita M, Xu J, Morokuma D, Hirata K, Hino M, et al. (2017) Characterization of Recombinant Thermococcus kodakaraensis (KOD) DNA Polymerases Produced Using Silkworm-Baculovirus Expression Vector System. Molecular Biotechnology. Available: http://dx.doi.org/10.1007/s12033-017-0008-9.

Acknowledgements
We thank Dr. Imanishi (National Institute of Agrobiological Sciences, Japan) for providing the NIAS-Bm-oyanagi2 (BmO2) cell line.

Publisher
Springer Nature

Journal
Molecular Biotechnology

DOI
10.1007/s12033-017-0008-9

PubMed ID
28484957

Additional Links
http://link.springer.com/article/10.1007/s12033-017-0008-9

Permanent link to this record