Changes in the intrinsic electrocatalytic nature of Na+/K+ ATPase reflect structural changes on ATP-binding: Electrochemical label-free approach

Chronopotentiometric stripping (CPS) analysis was used to show that transmembrane protein Na+/K+-ATPase (NKA) structural changes can be observed in the presence of ATP. The ATP-induced structural changes lead to modulation of NKA ability to catalyze the hydrogen evolution on Hg-electrode. The electrochemical data on NKA are compared to monitoring of changes in intrinsic fluorescence and discussed with respect to crystallographic structures of homologous sarco/endoplasmic reticulum Ca2 +-ATPase (SERCA). The results show that CPS analysis of intrinsic electroactivity (label-free approach) could be applied for monitoring of structural changes and molecular interactions of membrane proteins, such as NKA.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► The structural changes of membrane protein (MP) are investigated electrochemically. ► CPS analysis showed that Na+/K+-ATPase structural changes can be observed. ► The methodology is based on MP intrinsic electroactivity measurement. ► There is a first step towards future electroanalysis of MP structural modifications.