New Model Delves into Protein Folding

Scientists from the Pacific Quantum Center of Far Eastern Federal University have discovered how the AFV3-109 protein with slipknot structure folds and unfolds depending on temperature. Their findings were published in PLOS ONE.

Using numerical methods and applying quantum field theory that is unique for the study of proteins, the team have probed into the folding topology of the AFV3-109 protein featured with a slipknot.  One of the things they discovered was that the sliding knot of the AFV3-109 protein goes through an intermediate knot, which has the topology of a much more complex trefoil knot, a simplest non-trivial knot in mathematics.

They also discovered that before folding of the slipknot is complete, it precedes the swelling of the almost practically correctly folded AFV3-109 structure in a manner that the free end of the protein can pass into the loop of the knot. Lastly, they found that the correct protein structure formation is divided into stages. At the beginning solid secondary structures form, i.e. threads and spirals, and then they fold into a regular knot.

"In our work, we investigate the laws of symmetry that govern the behavior of a protein molecule. We managed to find out that local and chiral symmetry properties completely determine these complex processes and the non-trivial form of the protein," proceeds Alexander Molochkov. "This further confirms that every part of the protein is critical for the entire molecule to function properly. It also means that field theory is relevant for modeling the behavior of proteins that underlie all life."