Apr 7, 2011 07:33 GMT  ·  By
RPI researchers confined lysozyme and other enzymes inside carefully engineered nanoscale holes
   RPI researchers confined lysozyme and other enzymes inside carefully engineered nanoscale holes

Experts at the Rensselaer Polytechnic Institute (RPI) managed to develop a technique that enables them to increase the stability of enzymes. These molecules are part of a special class of proteins, and their primary role is to act as catalyst for most of the chemical reactions taking place inside cells.

Proteins in general are among the most interesting, mysterious, and least-understood structures in nature. They are tremendously complex, partially because many of them look the same, but differ only through the shape they have. However, their functions are radically different.

The exact same thing holds true for enzymes. While they do perform their actions flawlessly in their natural environment, they quickly degrade and deform when they are taken out of it. In other words, they become unstable.

In the new study, RPI professor Marc-Olivier Coppens managed to overcome this limitation by developing a method of boosting enzyme stability outside of their natural environment. This makes the molecules available for use in a wider array of conditions than previously thought possible.

According to the expert, boosting enzyme stability is easy, if you place them inside carefully engineered nanopores, which are essentially nanoscale holes, several times smaller than the width of a human hair.

When embedded in such structures, the enzymes no longer deteriorate when removed from their environment, but rather retain the vast majority of their 3D structure. At the same time, they exhibit a boost in activity levels, the professor explains.

“Normally, when you put an enzyme on a surface, its activity goes down. But in this study, we discovered that when we put enzymes in nanopores – a highly controlled environment – the enzymatic activity goes up dramatically,” Coppens explains.

“The enzymatic activity turns out to be very dependent on the local environment. This is very exciting,” he goes on to say. The professor is based at the RPI Department of Chemical and Biological Engineering.

Details of the new investigation and the methods used appear in a paper published in the March issue of the esteemed journal Physical Chemistry Chemical Physics. The work is entitled “Effects of surface curvature and surface chemistry on the structure and activity of proteins adsorbed in nanopores.”

Funds for the research came from the US National Science Foundation (NSF), the RPI Nanoscale Science and Engineering Center for Directed Assembly of Nanostructures, and the National Institute for Materials Science (NIMS) International Center for Materials Nanoarchitectonics, in Japan.