Electroconformational Denaturation of Membrane Proteins

Abstract

Because of high electrical impedance of cell membrane, when living cells are exposed to an external electric field, the field-induced voltage drops will mainly occur on the cell membrane. In addition to Joule heating damage and electroporation of the cell membrane, the electric field-induced supraphysiological transmembrane potential may inevitably damage the membrane proteins, especially the voltage-dependent membrane proteins. That is because the charged particles in the amino acid of the membrane proteins and, in particular, the voltage-sensors in the voltage-dependent membrane proteins are vulnerable to the membrane potential. An intensive, brief electric shock may induce electroconformational damage or denaturation in the membrane proteins. As a result, the cell functions are significantly reduced. This electric field-induced denaturation in the membrane proteins strongly suggests a new underlying mechanism involved in electrical injury.