The function of BST (Bacillus stearothermophilus) polymerase, also known as Bst polymerase, is to catalyze the synthesis of DNA strands from deoxyribonucleotide triphosphates (dNTPs) using single-stranded DNA as a template. This enzyme is widely used in molecular biology techniques such as polymerase chain reaction (PCR), DNA sequencing, site-directed mutagenesis, and DNA labeling.

BST polymerase, like other DNA polymerases, plays a crucial role in DNA replication and amplification processes. It adds nucleotides to the growing DNA strand in a template-dependent manner, utilizing the complementary base pairing between the template strand and incoming nucleotides (dNTPs). This results in the synthesis of a new DNA strand that is complementary to the template.

One notable feature of BST polymerase is its high thermal stability, which allows it to withstand the high temperatures required for denaturation steps in PCR. This characteristic makes it particularly useful in isothermal amplification techniques where elevated temperatures are necessary for DNA amplification without the need for thermal cycling.

In essence, Bst polymerase serves to facilitate the amplification and replication of DNA molecules across a spectrum of molecular biology applications, thereby contributing to advancements in research, diagnostics, and biotechnology. At SBS Genetech, we've developed a range of novel Bst polymerase variants endowed with additional functionalities. Let's delve deeper into these innovations.

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 is intricately tied to your research objectives, 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