Exceptional enzymes

All organisms depend on enzymes to speed up a vast array of chemical reactions inside their bodies, including those linked to respiration, protein synthesis and DNA replication.

Humans have long put enzymes to good use, for example to make beer. When brewers malt barley grain, they release a host of enzymes that help break down starch and boost levels of fermentable sugars, as well as improving filtration. These days, brewers also add tailor-made enzymes. Meanwhile, fruit juice producers add enzymes to increase juice yield.

Most enzymes are simply proteins that act as catalysts to accelerate chemical reactions. They contain active sites that lock onto specific chemicals (substrates) in reactions.

Also known as biological catalysts or biocatalysts, enzymes are now helping the chemical and pharmaceutical industries to become greener, reducing a need for rare earth metal catalysts and organic solvents, as well as increasing productivity.

The past decade has seen a small surge in industrial use of biocatalysts, thanks to protein and gene technologies that allow them to be engineered to specifically meet the demands of industrial processes.

To begin with, researchers turned to enzymes from known biological processes. However, the field has advanced so much that they can now engineer enzymes for chemical transformations that are not known in the biological world.