Bringing mixed enzymes back to life

A MIXTURE of different enzymes has been recovered for the first time, using a method that researchers believe could lower costs and simplify production of drugs for Alzheimer’s and Parkinson’s disease.

Proteins such as enzymes are important components and process accelerators used to manufacture many drugs and food products. However, due to processing conditions such as strong acids, bases or heating, around 80% typically denature – losing their shape and activity. Current renaturing technologies to revive spent proteins are specific to a certain protein, and so processing mixtures can be costly and time-consuming.

Now, a team of researchers has published a paper describing a method capable of renaturing several types of enzymes at once. The team, from ITMO University in Russia and the Hebrew University of Jerusalem in Israel, say that their alumina nanoparticle-assisted refolding technique is a world first, and capable of high yields.

First author of the Scientific Reports paper, Katerina Volodina, said: “Constant exposure of denaturing agents and the tendency of curling macromolecules to aggregation are major obstacles for recovering proteins. When removing these factors, we were able to regenerate our objects.'

They achieved this by using the electrostatic binding ability of highly positively-charged alumina nanoparticles. Due to electrostatic interaction, enzymes attracted the nanoparticles and engaged them, forming a supramolecular complex with physical bonds. The complexes were then centrifuged and separated from the denaturing solution by transferral to a buffer solution. After washing, the proteins started to refold to their native shape, and nanoparticles were recharged by changing pH.

Three enzymes were demonstrated to be unfolded by the technique: carbonic anhydrase, acid phosphatase and horseradish peroxidase. The authors also applied their method to a mixture of the former two complexes, and were able to recover more than half of the renaturated molecules.

Volodina said: “Renaturing of multiprotein mixtures is a unique process that has never been done before. But my colleagues and I believe that further research in this area is in the great interest of pharmaceutical companies right now.

“Theoretically, our method can simplify and cheapen the manufacture of drugs for Alzheimer's or Parkinson's therapy. Many of these medicines are made of proteins.”

Scientific Reports: http://doi.org/b8hw