Transmembrane carboxyl residues are essential for cation-dependent function in the gastric H,K-ATPase.

The Journal of Biological Chemistry
E C RabonK Smillie

Abstract

The K+-dependent ATPase activity of the H,K-ATPase was irreversibly inhibited by the carboxyl activating reagent, dicyclohexylcarbodiimide (DCCD). The inhibition was first order and displayed a concentration dependence with the K0.5 (DCCD) = 0.65 +/- 0.04 mM. KCl protected 70% of the ATPase activity from DCCD-dependent inhibition in a concentration-dependent manner with a K0.5 (K+) = 0.58 +/- 0.1 mM KCl. DCCD modification selectively inhibited the K+-dependent rather than ATP-dependent partial reactions including eosin fluorescence responses and ligand-stabilized initial tryptic cleavage patterns of the membrane-associated enzyme. DCCD modification also inhibited the binding of 86Rb+ and the fluorescent responses of the K+-competitive, fluorescent inhibitor 1-(2-methylphenyl)-4-methylamino-6-methyl-2, 3-dihydropyrrolo[3,2-c]quinoline. [14C]DCCD was incorporated into the H,K-ATPase in a time course identical to that describing the inactivation of the K+-dependent ATPase activity of the H,K-ATPase. A component of the [14C]DCCD incorporated into the H,K-ATPase was K+-sensitive where K+ reduced the [14C]DCCD incorporated into the enzyme by 1.6 nmol of [14C]DCCD/mg of protein. Membrane-associated tryptic peptides resolved from the [...Continue Reading

References

Jan 21, 1977·Biochimica Et Biophysica Acta·H ChangG Sachs
May 7, 1992·Biochimica Et Biophysica Acta·K BambergG Sachs
Aug 1, 1992·Proceedings of the National Academy of Sciences of the United States of America·R GoldshlegerS J Karlish
Jul 8, 1992·Biochimica Et Biophysica Acta·A Smolka, K M Swiger
Apr 8, 1991·Biochimica Et Biophysica Acta·K HallE Rabon
Jan 1, 1990·The American Journal of Physiology·C H Pedemonte, J H Kaplan
Jan 1, 1990·Annual Review of Physiology·E C Rabon, M A Reuben
Jun 1, 1990·Proceedings of the National Academy of Sciences of the United States of America·S J KarlishW D Stein
Jul 6, 1990·Biochimica Et Biophysica Acta·E C RabonL J Jakobsen
Jun 26, 1986·Biochimica Et Biophysica Acta·M L Helmich-de JongJ J De Pont
Nov 2, 1987·Biochimica Et Biophysica Acta·M ShaniS J Karlish
Dec 11, 1987·Biochimica Et Biophysica Acta·M L Helmich-de JongJ J de Pont
Nov 30, 1988·Biochemical and Biophysical Research Communications·M MaedaM Futai
Apr 25, 1973·Biochimica Et Biophysica Acta·A L Ganser, J G Forte
Jun 18, 1993·Biochimica Et Biophysica Acta·F MercierH Wong
Mar 1, 1993·The Journal of Membrane Biology·M StengelinE Bamberg
Jun 5, 1993·Biochimica Et Biophysica Acta·J M ShinG Sachs

❮ Previous
Next ❯

Citations

May 23, 2001·Archives of Biochemistry and Biophysics·S J RulliE C Rabon
Sep 5, 1997·The Journal of Biological Chemistry·M BesanconJ M Shin

❮ Previous
Next ❯

Related Concepts

Related Feeds

ASBMB Publications

The American Society for Biochemistry and Molecular Biology (ASBMB) includes the Journal of Biological Chemistry, Molecular & Cellular Proteomics, and the Journal of Lipid Research. Discover the latest research from ASBMB here.