Although not a very bold prediction in the current political climate, it is likely that “green” sciences are going to gain in popularity among our students. For many of us who teach Biochemistry and Molecular Biology, however, there is a feeling that this enthusiasm will not enhance the enrollment or engagement in our area of science. While we all recognize the very exciting advances in areas such as biofuel production and biological methods for environmental remediation, we pass up an important opportunity if we do not include this enthusiasm for all things “green” in our curricular development. As part of our efforts to demonstrate the relevance of understanding enzyme mechanisms and kinetics, for example, it might be helpful if students understood the principles of “green chemistry” and how enzymes could play a crucial role. Proposed by Anastas and Warner a decade ago [1], these values virtually dictate that biocatalysis become the alternative to much of industrial chemistry. With my apology to the authors for paraphrasing, principles such as “prevent waste,” “design safer chemicals and products,” “design less hazardous chemical syntheses,” “use catalysts, not stoichiometric reagents,” “avoid chemical derivatives,” “use safer solvents and reaction conditions,” “increase energy efficiency,” and “minimize the potential for accidents” are all calls for the use of enzymes in chemistry and for the appreciation of the opportunities in industrial biotechnology as a driver of “green” technology. Students might be intrigued to explore a specific case study where biocatalysts replace chemical reactions for the production of a pharmaceutical, and to appreciate that in many cases, it is not just environmentally, but economically justified. Rozzell presents a compelling case [2] for the use of biocatalysis in precisely this context as he describes the production of atorvastatin, the key ingredient in the cholesterol-lowering drug Lipitor®. Rozzell describes how he and his colleagues designed a technique to alter the chemical specificity of various enzymes so that they would efficiently catalyze two of the steps in the manufacture of Lipitor®. Comparing the enzymatic synthesis of one of the intermediates to the patented chemical synthesis, Rozzell calculates (see ref.2) that the solvent use goes from 27.5 L/kg in the chemical synthesis to 3.2 L/Kg in the enzymatic process, but diasteriometric purity of the enzymatically produced compound is far better. Since Lipitor® has become one of the best selling drugs in the world, decreasing the environmental footprint of manufacture has significant impact. The lessons and potential cases of “Green Biotechnology” do not stop at statins. Drug discovery and an understanding of the role of drug metabolites have been markedly enhanced by studying the P450 system in both in vivo and in vitro experiments. The fulfillments of several of the principles of “green chemistry” are evident in an examination of the discussion of Mayhew et al. [3] and would easily stimulate a fruitful discussion of hydroxylation, drug metabolism, or drug development strategies. Practically every area of enzymology has similar case studies available. Of course no discussion of “Green Biotechnology” would be complete if the agricultural and food issues were not brought forth. In terms of engaging students in lively discussions that require scientific understanding, reading of policy, and an appreciation of commerce and trade, nothing is better than exploring the European Union and its policies on Biotechnology foods (a.k.a. genetically modified foods or GMOs). It is especially interesting if we attempt to understand the differences in US and EU policies and acceptance. As a start for such discussion one interesting representation of one side is presented as the “Green Biotechnology Manifesto” (see: http://www.greenbiotech-manifesto.org/). The variety of opinions, views, and perspectives on this topic could serve to provide cases for unlimited class engagement, but the opportunity to provide a context of rigorous economic analysis and peer-reviewed science is never in excess. Green Biotechnology should be spectacularly attractive to our students interested in using science to preserve the environment, and at the same time develop a vibrant economy. What is lacking is a supply of established cases that can readily be used in the classrooms where we teach Biochemistry and Molecular Biology. It is a timely opportunity that BAMBED and its readers can fulfill.
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