The Role of Enzymes in Sustainable Pharmaceutical Manufacturing

Within this dynamic and changing pharmaceutical production environment, sustainability has emerged as an essential factor. Rising requests for eco-friendly and more effective processes have compelled the industry to develop fresh strategies that reduce environmental burden without compromising productivity or even enhance productivity. A development that has gained considerable fraction in recent years is the application of enzymes as biocatalysts in pharmaceutical manufacturing. Therefore, enzymes represent an almost revolutionary solution to many problems from classic chemical synthesis, thanks to their unique selectivity and efficiency at mild conditions. The article below discusses the contribution of enzymes towards growing up pharmaceutical manufacturing, considering applications in various steps of drug synthysis and advantages over classical approaches; but also, future perspectives on industrial biocatalysis are given.

The Promise of Biocatalysis in Pharmaceuticals

Biocatalysis utilizes natural catalysts for chemical transformations. Enzymatic catalysis, especially those with high specificity, reduces the need for protection groups and simplifies synthetic routes. This enzymatic specificity increases yields of desired products and/or reduces the formation of by-products, thus leading to cleaner processes that are often more efficient. It is also done under mild conditions; usually, ordinary temperature and pressure and aqueous environments are sufficient. This is in contrast to the very harsh conditions usually applied in classical chemical syntheses. As such, this lowers energy use and the need for dangerous chemicals, hence positioning biocatalysis in a place of relevance within the principles of green chemistry.

Biocatalytic Processes in Drug Synthesis

API synthesis is one of the most significant applications of enzymes in the pharmaceutical field. Classic chemical synthesis usually involves multistep processes with all kinds of reagents and catalysts, so such processes are usually complex and very time- and cost-consuming. Enzymes would make it much easier because they would catalyze certain reactions with high selectivity and efficiency, mostly combining several steps into one.

This was much improved, for example, by the application of immune reduces and reductive aminases in the synthesis of chiral amines, a common structural motif in many drugs. These biocatalysts allow entry to chiral amines at high enantioselectivity, thereby saving additional purification steps and generally increasing process efficiency. The industrial application of these enzymes successfully scales from milligram to tone levels, showcasing their use in large-scale pharmaceutical production.

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Enzyme Engineering: Expanding the Biocatalytic Toolbox

Whereas the capabilities of enzymes are phenomenal, definitely there is a limit to their abilities. Most enzymes are substrate-specific or work optimally under conditions that might not be the same as those relevant to pharmaceutical manufacture. The engineering of enzymes has become a very strong tool in overcoming such limitations. It involves modifying amino acid sequences of enzymes, improving stability, broadening substrate range, and enhancing activity at industrial conditions.

A classic example is the engineering of penicillin G acylases for the selective modification of peptides and proteins. These enzymes have now been designed to discriminate between free amino groups inside complex molecules, thereby enabling the site-specific functionalization of proteins like insulin. This technique, besides improving yield and purity of the product, also opens up new avenues for the development of protein-based therapeutics.

Sustainability Via Biocatalysis

Sustainability in pharmaceutical manufacturing is not just about reducing energy consumption and waste but also about using fewer hazardous chemicals and organic solvents. Enzymes, by their very nature, foster sustainability. This is because enzymes typically act in aqueous conditions, and at physiological levels, these include the use of harmful organic solvents and reduce the risks of toxic by-products.

It is also noticed that the carbon footprint of pharmaceutical synthesis can be significantly reduced by biocatalysis. Most enzymatic processes require less energy supply and generate a lower volume of CO2 when compared with traditional chemical transformations. The antiviral drug Molnupiravir, for instance, was biocatalytically synthesized using an engineered ribosyl-1-kinase, therefore enabling a much more streamlined and effective route of synthesis. This represents a 70% reduction in synthetic steps with an improved overall yield, thus offering significant environmental and economic benefits through the use of biocatalysis.

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The Future of Enzymes in Pharmaceutical Manufacturing

The applications in manufacturing by enzymes will keep growing with the evolution of the pharmaceutical industry. Nowadays, bioinformatics and protein engineering are enabling the discovery and development of novel biocatalysts showing improved properties. Such enzymes will not only allow the synthesis of existing drugs but also make possible the development of other therapeutic agents that previously have not been prepared due to difficulties or impossibilities.

Another exciting area is the interfacing of biocatalysis with other emerging technologies, such as flow chemistry and synthetic biology. Flow chemistry, involving continuous processing of chemical reactions, is highly compatible with biocatalysis. Enzymes can be immobilized in flow reactors, continuously producing pharmaceuticals with high efficiency and low waste. This technique has already demonstrated immense promise in the synthesis of complex molecules, and when put together with biocatalysis, it might have the power to change the way pharmaceutical manufacturing is done.

Synthetic biology, on the other hand, allows for the engineering of new metabolic pathways that synthesize drugs. Designing synthetic pathways, combining multiple enzymes either in one microorganism or a cell-free system that results in the production of very complex drugs from simple starting material, is possible. This approach not only increases efficiency but also reduces reliance on feedstocks derived from petrochemical sources, further enhancing the sustainability of pharmaceutical manufacturing.

Challenges and Considerations

Despite the huge advantages of enzymes in pharmaceutical manufacturing, many challenges are yet to be overcome. One such very important point to consider is scalability. Going from laboratory processes via pilot-scale to large industrial-scale processes may be cumbersome and thus expensive. In addition, enzymes may not be stable under industrial conditions, such as high temperatures or extreme pH values, which constitutes another serious limitation of this technology.

Improvements in the immobilization of enzymes, a process in which enzymes are attached to solid supports, have shown promise in enhancing enzyme stability and reusability. Research toward overcoming these challenges is directed at enhancing the robustness and scalability of enzymes. The development of enzyme kits providing ready-to-use collections of biocatalysts for specific applications for pharmaceutical manufacturers may help the path toward large-scale implementation of biocatalysis.

Another aspect is that of regulation. As the biocatalytic processes increasingly become the norm, then regulations will necessarily come along the way to determine how these biocatalytic processes will be put into use in pharmaceutical manufacturing. Assuring the safety and efficiency of drugs produced through biocatalytical means will be determinant to gaining regulatory acceptance and marketability of drugs.

Conclusion

Enzymes are playing an increasingly important role in sustainable pharmaceutical manufacturing. With high specificity, mild reaction conditions, and negligible environmental impact, they represent ideal candidates for applications in green chemistry. The further the areas of enzyme engineering, bioinformatics, and synthetic biology are developed, the higher will be the potential for biocatalysis in drug synthesis. In this light, embracing such technologies will advance the efficiency and sustainability not just of its manufacturing process but of the pharmaceutical industry as a whole. This also opens new horizons for drug development and the management of its production. The future of pharmaceutical manufacturing is undoubtedly biocatalytic, and as the industry moves towards greener and more sustainable practices, enzymes will be at the forefront of this transformation.

References

  1. Van Giesen, K.J., Thompson, M.J., Meng, Q. and Lovelock, S.L., 2022. Biocatalytic synthesis of antiviral nucleosides, cyclic dinucleotides, and oligonucleotide therapies. JACS Au3(1), pp.13-24.
  2. Ruccolo, S., Brito, G., Christensen, M., Itoh, T., Mattern, K., Stone, K., Strotman, N.A. and Sun, A.C., 2022. Electrochemical recycling of adenosine triphosphate in biocatalytic reaction cascades. Journal of the American Chemical Society144(49), pp.22582-22588.
  3. Kinner, A., Nerke, P., Siedentop, R., Steinmetz, T., Classen, T., Rosenthal, K., Nett, M., Pietruszka, J. and Lütz, S., 2022. Recent advances in biocatalysis for drug synthesis. Biomedicines10(5), p.964.
  4. Fessner, N.D., Badenhorst, C.P. and Bornscheuer, U.T., 2022. Enzyme Kits to facilitate the integration of biocatalysis into organic chemistry–first aid for synthetic chemists. ChemCatChem14(11), p.e202200156.
  5. McIntosh, J.A., Benkovics, T., Silverman, S.M., Huffman, M.A., Kong, J., Maligres, P.E., Itoh, T., Yang, H., Verma, D., Pan, W. and Ho, H.I., 2021. Engineered ribosyl-1-kinase enables concise synthesis of molnupiravir, an antiviral for COVID-19. ACS Central Science7(12), pp.1980-1985.
  6. Harrison, W., Huang, X. and Zhao, H., 2022. Photobiocatalysis for abiological transformations. Accounts of chemical research55(8), pp.1087-1096.
  7. Fryszkowska, A., An, C., Alvizo, O., Banerjee, G., Canada, K.A., Cao, Y., DeMong, D., Devine, P.N., Duan, D., Elgart, D.M. and Farasat, I., 2022. A chemoenzymatic strategy for site-selective functionalization of native peptides and proteins. Science376(6599), pp.1321-1327.
  8. Young, R.J., Flitsch, S.L., Grigalunas, M., Leeson, P.D., Quinn, R.J., Turner, N.J. and Waldmann, H., 2022. The time and place for nature in drug discovery. Jacs Au2(11), pp.2400-2416.
  9. Zetzsche, L.E., Chakrabarty, S. and Narayan, A.R., 2022. The transformative power of biocatalysis in convergent synthesis. Journal of the American Chemical Society144(12), pp.5214-5225.

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