Proteins in electric fields

Proteins are large biological molecules that play diverse and critical roles in the functioning of living organisms. They are responsible for carrying out various tasks necessary for cellular structure, communication, and regulation. Proteins possess electric charges due to the composition of amino acids, which can be positively, negatively, or neutrally charged. These charges determine protein electrostatic behavior, governing vital functions of proteins. Electrostatic properties guide protein folding, affect stability, and facilitate interactions with other molecules. Electrostatic forces are pivotal in enzyme catalysis, protein-protein binding, and complex formation, underpinning essential biological processes. External electric field can therefore act on protein charged groups by force and can be used to modulate and manipulate protein structure and function. The current knowledge is that the electric field causes linear motion (electrophoresis) or rotation of proteins. However, ongoing research suggests that intense external electric field can promote also protein conformation changes, affect secondary structure and thus modifying enzymatic function or the formation of higher order complexes and assemblies. The detailed understanding of these intricate effects can open new applications ranging from nanobiotechnology to biomedicine.

Figure caption:
Electric field exerts effects on protein via force on electrically charged groups. The effects can be primary in character, such as electrophoretic linear motion, rotation, change in secondary structure and protein shape. These primary effects then translate to secondary effects on protein electrostatic and mechanical properties, multivalent interaction between the proteins, as well as protein function.

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