A team of biochemists at the University Of Pennsylvania School Of Medicine have created a new type of protein that can carry oxygen. They built the protein from scratch by studying natural proteins and their principles. Protein engineers can already take an existing protein and tweak it to perform a new function. However, the team in Pennsylvania didn’t re-engineer a natural protein; instead they made one from scratch. Natural proteins are very complex and fragile whereas, the new protein is simple and robust.
The protein carries oxygen in the same way that neuroglobin carries oxygen to the brain and nervous system. The team at University of Pennsylvania believe that the protein could be used to make artificial blood. To build the protein they started with three amino acids to form a helix shaped column. From this, they built four columns that resemble a candelabra. They added heme, a chemical group that contains an iron atom that can bind the oxygen molecules. Also, to allow the columns to open up and capture the oxygen they used another amino acid called glutamate. A robot was used to chemically stick the amino acids together.
Leslie Dutton, a member of the team said, “Our approach to building a simple protein from scratch allows us to add on, without getting more and more complicated.” Re-engineered natural proteins provide a base to define and test different protein engineering principles. However, further research of these principles will be made much easier by using the new completely artificial proteins as a clean slate to work with.
References:
University of Pennsylvania School of Medicine (27/3/09). Proteins By Design: Biochemists Create New Protein From Scratch. ScienceDaily. http://www.sciencedaily.com¬ /releases/2009/03/090323154349.htm
P. Leslie Dutton. Design and engineering of an O2 transport protein. Nature, 2009; 10.1038/nature07841
