Designing easy-to-use enzymes for clinical diagnostics and life science research

Easy-to-use polymerases engineered for fast detection and designed for state-of-the-art applications in molecular biology and diagnostics are key for both life science reasearchers performing critical experiments and technicians carrying out diagnostic testing.

Rita Simões, Junior Scientist at NZYTech’s R&D department, has dedicated her time to an important research and development project intended precisely for that purpose. A new NZY Bst DNA polymerase, part of a new generation of DNA polymerases, developed and optimized for standard Loop-mediated isothermal amplification (LAMP) applications and also suitable for nucleic acid amplification methods requiring strand displacement activity, such as whole genome amplification (WGA) and Multiple displacement amplification (MDA).

Today we speak with Rita and delve into the motivation, challenges, interesting features and applications of this new polymerase from research to development to application.

1. What was the motivation behind NZYTech’s R&D departament conception of the novel NZY Bst DNA polymerase?

Following the outbreak of COVID-19, the improvement of diagnostic tests became increasingly important to overcome the overload of the healthcare system and the limited supply of reagents required for the setup of these tests. Thus, we intended to develop a robust polymerase which provided a fast detection, was easy-to-use and inexpensive as a means of accelerating molecular diagnostics.

2. What were the major challenges you faced throughout the R&D process regarding the development of this particular polymerase?

Loop-mediated isothermal amplification (LAMP) is an autocycling DNA synthesis method involving the use of a polymerase displaying strand displacement function, and a set of four to six specially designed primers. To ensure that NZY Bst DNA polymerase was robust in a LAMP setup we devised several strategies to improve the enzyme’s intrinsic stability (including thermostability), processivity and speed.

3. What is the most interesting feature or the most surprising result during the development of the MB444?

The most interesting feature of NZY Bst DNA polymerase is its high strand-displacement activity, which means that this polymerase can synthesize a complementary DNA strand while simultaneously breaking the hydrogen bridges of the target double-stranded DNA. Therefore, amplification of target-DNA can be performed at a single incubation temperature (with an optimal activity at 63⁰C) reducing detection time and costs as an expensive thermocycler is not required.

4. What are to you the most useful applications of the NZY Bst DNA polymerase?

Its main application would be to both LAMP (loop-mediated isothermal amplification) and RT-LAMP assays which I believe will eventually become the gold-standard in the field of molecular diagnostics. Currently the most common technique used in this field is PCR, however the time-to-results of this method is quite extensive which can become a bottleneck in the face of an epidemic where diagnostics laboratories become overburdened. LAMP has a sensitivity which is equal to or higher than that of PCR with the advantage of a shorter detection time.

This polymerase can also be used for whole genome amplification (WGA) or multiple displacement amplification (MDA).

5. Who do you see using this product the most and for what applications?

One of the strong points of this enzyme is its ease of use, making it compatible with the work of most users ranging from a clinical technician performing diagnostic tests to a student looking to perform reliable experimental work.

6. How does NZY Bst DNA polymerase do performance-wise and how does it compare with similar products?

Our polymerase has a performance above average with a time-to-result value lower than most competitors in the market. During the benchmark we conducted, NZY Bst DNA polymerase consistently produced faster detection of targets in different models (e.g. SARS-CoV-2, Homo sapiens and Escherichia coli) when compared to a series of enzymes from competitors.

7. Where do you see the landscape of R&D for Bst DNA Polymerases headed in the next five to ten years?

We are just now beginning to tap into the potential of these polymerases therefore we will certainly want to further investigate how we can improve the activity of these enzymes. An interesting feature to explore would be its resistance to common PCR inhibitors, for example, which is a hinderance commonly identified in diagnostic laboratories. An equally interesting challenge would be to further reduce the time-to-result by engineering the enzyme in this sense.