Difference Infrared Spectroscopy of the Gastric H+, K+-Atpase

The gastric H+, K+-ATPase is an a, β heterodimer which belongs to the P-type ATPase family (1, 2). Little is known about their structure and the reactions which couple ATP hydrolysis to cation transport. Infrared spectroscopy was used in combination with a proteolytic approach to gain information on the structure of the membrane embedded part of the H+, K+-ATPase (3).