Professor David Lilley most recent research findings have been published in Nature Chemical Biology today. The paper describes the crystal structure of a new ribozyme (called TS). Ribozymes are RNA molecules that act like enzymes to accelerate chemical reactions. The great majority of enzymes are made of proteins, but a small sub-set are made of RNA (a close chemical cousin of the familiar DNA).
In Professor Lilley’s laboratory, a major goal of their research is to understand how RNA can achieve this chemical feat. They employ a combination of chemical, mechanistic experiments together with X-ray crystallography to determine their 3D structures. Their data from this study indicates that this particular ribozyme functions mainly as a metalloenzyme where metal ions, in this case a magnesium ion, bind to the structure to directly participate in the chemical reaction.
Professor Lilley explains the importance of the research included in the paper “First, these species exist in cells, and more are being found quite regularly now. Ribozymes mediate some of the most important reactions in the cell, including making proteins so it’s important to understand how they work. Second, many of us feel that ribozymes were incredibly important during the very early origins of life on this planet. In a sense, we are almost peering back billions of years to those early stages of primitive life.”
Image: TS ribozyme. The structure is shown with the nucleotides (the building blocks of the RNA) in cartoon form, with a grey ribbon showing the path of the backbone. A number of metal ions (green spheres) are bound to the structure, with their associated water molecules (red spheres). The magenta sphere shows the site in the RNA structure where chemistry occurs.