BST (Bacillus stearothermophilus) polymerase, commonly known as Bst polymerase, is a staple in Loop-Mediated Isothermal Amplification (LAMP) for its tailored features that align perfectly with this technique:

High Thermal Stability: Bst polymerase boasts exceptional stability at elevated temperatures, a must for LAMP reactions held consistently between 60°C to 65°C. This resilience allows it to endure the prolonged high temperatures needed for DNA denaturation, annealing, and extension during amplification.

Robust Strand Displacement Activity: With robust strand displacement activity, Bst polymerase efficiently displaces DNA strands ahead of the polymerization process, streamlining DNA amplification without the need for thermal cycling. This trait is vital for the continuous amplification nature of LAMP, where displaced DNA strands act as templates for further amplification.

Amplification of Complex Templates: Bst polymerase excels in amplifying DNA templates with intricate secondary structures, like hairpins or loops, often encountered in LAMP reactions. Its robust strand displacement activity helps navigate through these structures, ensuring efficient amplification of target sequences.

Isothermal Amplification Competence: Operating as an isothermal amplification technique, LAMP functions at a constant temperature without requiring complex thermal cycling equipment. Bst polymerase's ability to operate optimally at a single, constant temperature simplifies experimental setup, reducing reliance on sophisticated thermal cycling instruments, thus making LAMP accessible for various applications, including field-based diagnostics.

Cost-effectiveness: In contrast to other DNA polymerases used in PCR-based techniques, Bst polymerase is relatively inexpensive, making it an attractive option for large-scale or resource-limited applications, such as point-of-care diagnostics or field-based testing.

In summary, BST polymerase's unique blend of thermal stability, robust strand displacement activity, and isothermal amplification capability positions it as an optimal enzyme for LAMP, enabling swift and sensitive detection of target nucleic acid sequences across various applications in research, diagnostics, and biotechnology.

At SBS Genetech, we've developed a range of novel Bst polymerase variants tailored to enhance their utility in LAMP. Let's explore these innovative solutions further.

Bst DNA Polymerase Large Fragment: Cost-effective version for conventional strand displacement reaction

Bst DNA Polymerase Large Fragment  is the portion of the Bacillus stearothermophilus DNA Polymerase protein that contains the 5´ → 3´ polymerase activity, but lacks 5´ →3´ exonuclease activity. It has basic strand displacement activity and can be used for isothermal amplification.

However, without further genetic engineering, the amplification speed, impurity tolerance, and specificity of Bst DNA Polymerase (Large Fragment) are not ideal. So we don't recommend this enzyme for most of your experiments.

Bst DNA Polymerase: Ideal for isothermal amplification of DNA template

Bst DNA Polymerase is also derived from Bacillus stearothermophilus DNA polymerase I. Its 5 '- 3' exonuclease activity was removed by genetic engineering, while the 5 '- 3' polymerase activity was retained.

As the name suggests, Bst DNA Polymerase has a strong strand-displacement ability for DNA template, so it is an excellent enzyme for isothermal amplification.

Compared with wild-type Bst DNA polymerase (large fragment), Bst DNA Polymerase has been greatly improved in terms of amplification speed, yield, salt tolerance, and thermal stability.

At the same time, Bst DNA Polymerase can be amplified with dUTP as substrate, while Bst DNA Polymerase (Large Fragment) has no such activity.

Bst Polymerase: For isothermal amplification of both DNA and RNA template with a single enzyme system

Bst Polymerase is also derived from Bacillus stearothermophilus DNA polymerase I. Its 5'- 3' and 3'-5' exonuclease activity was removed by genetic engineering, while the 5'- 3' polymerase activity was retained.

Compared with wild-type Bst DNA polymerase (large fragment) and Bst DNA Polymerase, Bst Polymerase has better isothermal amplification activity and stronger reverse transcription activity. Single enzyme system reaction can be realized in the isothermal amplification experiment with RNA as a template.

Bst Polymerase has good reverse transcription activity at 60-65°C, which can effectively solve the reverse transcription of the RNA template with secondary complex structure, while Bst DNA Polymerase and wild-type Bst DNA polymerase (large fragment) do not have this activity.

Bst DNA/RNA Polymerase: Ideal for isothermal amplification of RNA template

Bst DNA/RNA Polymerase is a mixture of Bst Polymerase and extremely thermostable reverse transcriptase (65°C tolerant), which is suitable for the isothermal amplification reaction of RNA. It can detect low-sensitivity RNA molecules.

Bst DNA/RNA Polymerase is suitable for isothermal amplification reaction of both DNA and RNA templates, which can detect low-sensitivity nucleic acid templates with great efficiency and specificity. Besides, with a special preparation process, this enzyme has a fast amplification rate and high tolerance to impurity.

Since Bst DNA/RNA Polymerase is extremely thermostable and also provides sensitive reverse transcriptase activity, it is reported to have higher sensitivity at high Ct values.^[1]

Bst P DNA/RNA Polymerase: The most advanced enzyme solution

Bst P DNA/RNA Polymerase is an upgraded version of Bst DNA/RNA Polymerase through enzyme electronic re-structure and evolution screening (in silico Design & in vitro Evolution), which is generally used for LAMP or RT-LAMP amplification of DNA or RNA.

Performance improvements include:

• The whole Bst P DNA/RNA System includes hot start Aptamer, which ensures that the enzyme activity blocking efficiency is >95% at <30°C, and the enzyme activity is completely released within 1 min at >60°C. This characteristic facilitates the establishment of the reaction system at room temperature and greatly reduces the non-specific amplification at low temperatures.
• The reaction temperature is further raised to 70°C, which greatly reduces the formation of primer dimer, improves the amplification specificity, and makes the nucleic acid release of crude samples more sufficient.
• The whole portfolio contains Helicase, so Premium LAMP amplification (pLAMP) is allowed without using F3/B3 primers. At the same time, Helicase has the function of assisting in strand unwinding, which further reduces the concentration of FIP/BIP primers. This will further reduce non-specific amplification and greatly improve amplification homogeneity.

Comparison between the most common Bst DNA Polymerase and the latest Bst P DNA/RNA Polymerase

In conclusion, the selection of a Bst polymerase variant hinges on your research objectives, with each offering distinct capabilities and benefits. We trust this comprehensive overview will guide you in selecting an enzyme that seamlessly aligns with your research pursuits. At SBS Genetech, our diverse array of Bst polymerases is meticulously curated to meet your varied requirements.

Reference

[1] Lu S, Duplat D, Benitez-Bolivar P, León C, Villota SD, Veloz-Villavicencio E, et al. (2022) Multicenter international assessment of a SARS-CoV-2 RT-LAMP test for point of care clinical application. PLoS ONE 17(5): e0268340. https://doi.org/10.1371/journal.pone.0268340