Part:BBa_K3815032

B. stearothermophilus DNA polymerase

Description of this part

Targeted protein

Fig1. ladder-like bands that are typical of LAMP reactions

This part is used to purify homemade BST DNA polymerase. This is derived from Geobacillus stearothermophilus. This enzyme is used for strand-displacing DNA synthesis in LAMP(Loop-Mediated Isothermal Amplification) or RT-LAMP(Reverse Transcription Loop-Mediated Isothermal Amplification). The enzyme has 5′-3′ polymerase activity and strand displacement activity, but it lacks 3′-5′ exonuclease activity. It also has reverse transcription activity. In our experiments, we observed the activity of homemade DNA polymerase ,which is comparable to commercial sources (BST3.0 from NEB) in LAMP reaction against DMV(dahlia mosaic virus). In Fig. 1 you see ladder-like bands that are typical of LAMP reactions.

Sequence and Features

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  INCOMPATIBLE WITH RFC[12]

  Illegal NheI site found at 393
  
• 21
  COMPATIBLE WITH RFC[21]
• 23
  COMPATIBLE WITH RFC[23]
• 25
  INCOMPATIBLE WITH RFC[25]

  Illegal AgeI site found at 1003
  
• 1000
  COMPATIBLE WITH RFC[1000]

Purification

Fig2. SDS-PAGE of purified proteins

Expression

• Cells were cultivated in 1000ml LB media at 37^oC shaking at 180 rpm to the log-phase.
• when the OD600 reaches 0.35-0.7, IPTG was added at the final concentration of 0.5mM to induce the peptide expression.
• After 3 hours of induction, cells were harvested and frozen in liquid-N2.

Purification

After the cell disruption by sonication, each protein was purified using Ni-NTA beads. Samples were eluted by a four-step gradient of Imidazole(70mM, 95mM, 120mM, 270mM).

Fig. 2 shows the result of SDS-PAGE. The lane 9,10,11,12 are the result of BST DNA polymerase.
We observed the correct bands in the SDS-PAGE gel. The arrowheads indicate the targeted proteins.

Reference

https://www.lucigen.com/docs/manuals/MA073-Bst-DNA-Polymerase-8-U.pdf