Recombinant Taq DNA polymerase.

The sudden COVID-19 pandemic highlights the importance of diagnostic assays in health security readiness. One persistent difficulty is the rapid molecular detection of pathogenic microorganisms and viruses. Taq DNA polymerase remains an essential component for COVID-19 molecular detection. Taq DNA polymerase exhibits a high level of thermostability, which results from tighter hydrophobic packing, increased salt bridges, shortened loops, and proline substitutions that reduce flexibility, enabling activity above 90 °C. In addition, engineered variants address limitations by improving fidelity, processivity, and stability. The enzyme´s thermostability has significantly increased the efficiency, automation, and specificity of PCR. Hot-start modifications using antibodies, aptamers, or chemical inhibitors further reduce non-specific amplification, strengthening its role in sensitive diagnostics. Although Taq polymerase is available from several commercial sources, it is crucial and urgent to produce enzymes recombinantly for use in research and diagnostic procedures. To satisfy the demands of industry, it is necessary to maximize and optimize its production. We provide an overview of the recombinant Taq DNA polymerase´s characteristics, structural features, engineering advances, production background and strategies, and purification history in this paper. Together, these insights underscore its central role in diagnostics, research, and biotechnology, as well as its continued relevance as a model enzyme for protein engineering.