U.S.-Germany Cooperative Research: Dynamics of ATP-Na(+),K(+)-ATPase Interactions

University Of North Carolina Greensboro, Greensboro NC

Investigators

Abstract

0072563 Pratap This one-year award for U.S.-Germany cooperative research in biochemistry involves Promod Pratap of the University of North Carolina in Greensboro and Uli Nienhaus of the University of Ulm in Germany. Dr. Pratap will spend seven months at the University of Ulm, conducting experiments on substrate binding to sodium/potassium ATPase (Na+/K+-ATPase), an enzymatic equivalent of a sodium pump. The pump couples energy released from ATPase hydrolysis with transport of sodium and potassium into the cell. It is regulated in vivo by insulin and thyroid hormone and serves as a receptor for digital glycoside drugs. The objective of the project is to understand the energy requirements for transport mediated by this sodium pump. The investigators will examine the interaction between the enzyme and ATP and probe changes in protein structure associated with ATP substrate binding. Two techniques will be employed; fourier-transform infrared (FTIR) spectroscopy and single-molecule fluorescence energy transfer (FRET). The U.S. investigator brings to this collaboration expertise in the proposed enzymatic system (sodium/potassium ATPase). This is complemented by similar German expertise. The project also takes advantage of specialized equipment (time-resolved visible infrared spectroscopy) available at the University of Ulm. Detailed molecular understanding of sodium/potassium ATPase will provide information about regulating cellular metabolism and energy balance.