Inactivation of Ca2(+)-, Na+K(+)-, and H+K(+)-ATPases with a carbodiimide derivative of ATP.

ABSTRACT

The gamma-P adduct of ATP with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (ATP-EDC) was synthesized and incubated with the Ca-ATPase of sarcoplasmic reticulum with the result that time-dependent complete loss of the enzyme's activity occurred. The inactivation required calcium and magnesium while ATP had a protective effect. ATP-EDC incubation with the NaK-ATPase and HK-ATPase produced partial (greater than 50%) inactivation, but had no effect on myosin S1, pyruvate kinase and hexokinase, suggesting that this ATP analog is a specific inactivator of the so-called 'P-type' ATPases.