About Protein Physics

Protein molecules are molecular machines (bio-nanomachines) on the nanometer (one billionth of a meter) scale that have evolved over a long period of time for life on Earth. Not only are they essential for daily life and for passing on life to the next generation, but they are also widely used in a variety of fields, including industry, agriculture, and medicine. Examples include industrial catalysts for producing useful substances quickly and at low cost, enzymes in household detergents, and the latest antibody drugs.

These useful functions of protein molecules (catalytic ability, binding ability, etc.) are part of the physical properties of protein molecules. The study of the physical properties is called protein physics.

Chemically, a protein molecule is a string of many different types of amino acids linked. The types and arrangement of amino acids are stored in life as genetic information, and are the subject of biological research. The fundamental properties of proteins are based on these biological and chemical structures (primary structure), but the physical properties are determined by the various three-dimensional structures that a single string forms under various environments (secondary, tertiary, and quaternary structures). In that sense, the three-dimensional (3D) structure of a protein molecule is one of the most important pieces of information for understanding and designing the protein properties.

Currently, there is some success in using AI to predict the 3D structure from the amino acid sequence (primary structure), but information on three-dimensional structures determined experimentally using X-ray crystallography, NMR (nuclear magnetic resonance), cryo-electron microscopy, etc. is more reliable. In addition, it is even more difficult to estimate the essential physical properties from the primary and 3D structures, and at present, it is necessary to actually use the protein samples and determine the physical properties from experimental data.

By making full use of the knowledge about protein properties that has been accumulated so far and the methods and technologies for determining the physical properties, it should be possible to create more useful and highly functional proteins and/or discover ways to utilize the proteins. In order to solve the environmental, food, and health problems of the 21st century, we aim to further develop protein physics.