Pre-steady-state kinetic study of the mechanism of inhibition of the plasma membrane Ca(2+)-ATPase by lanthanum

Biochemistry
C J Herscher, A F Rega

Abstract

Lanthanides are known to be effective inhibitors of the PMCa(2+)-ATPase. The effects of LaCl3 on the partial reactions that take place during ATP hydrolysis by the calcium-dependent ATPase from plasma membrane (PMCa(2+)-ATPase) were studied at 37 degrees C on fragmented intact membranes from pig red cells by means of a rapid chemical quenching technique. LaCl3 added before phosphorylation (K0.5 = 2.8 +/- 0.2 microM) raised the kapp of the E2-->E1 transition from 14 +/- 2 to 23 +/- 4 s-1. The effect was independent of Ca2+ and Mg2+, as if La3+ substituted for Mg2+ and/or Ca2+ in accelerating the formation of E1 with higher efficiency. At non-limiting conditions, LaCl3 doubled the apparent concentration of E1 in the enzyme at rest with Ca2+ and Mg2+. LaCl3 during phosphorylation (K0.5 near 20 microM) lowered the vo of the reaction from 300 +/- 20 to 60 +/- 7 pmol/mg of protein/s, a close rate to that in the absence of Mg2+. This effect was reversed by Mg2+ (and not by Ca2+), and the K0.5 for Mg2+ as activator of the phosphorylation reaction increased linearly with the concentration of LaCl3, suggesting that La3+ slowed phosphorylation by displacing Mg2+ from the activation site(s). If added before phosphorylation, LaCl3 lowered t...Continue Reading

Citations

Mar 26, 2004·Biophysical Journal·Etienne Roux, Marko Marhl
Nov 15, 2001·Hearing Research·A R PenheiterJ T Penniston
Nov 14, 2002·Insect Biochemistry and Molecular Biology·Heiner Birkenbeil, Skarlatos G Dedos
Aug 28, 1999·Journal of Pharmacological and Toxicological Methods·G R MonteithB D Roufogalis
Jul 29, 2011·The Journal of Biological Chemistry·Mariela S Ferreira-GomesJuan Pablo F C Rossi
Nov 20, 2001·Molecular and Cellular Biology·K OnoJ Han
May 9, 2002·Biochimica Et Biophysica Acta·Monica M FreireHelena M Scofano
Jun 6, 2009·The Biochemical Journal·Tanja KirchbergerAndreas H Guse
Nov 23, 2006·The International Journal of Biochemistry & Cell Biology·Carla F FelixHelena M Scofano
Jun 25, 2005·Biochimica Et Biophysica Acta·Otacilio C MoreiraHector Barrabin
Jan 22, 2015·The Journal of Biological Chemistry·María Florencia PignataroJuan Pablo F C Rossi
Sep 13, 2013·The Journal of Biological Chemistry·Irene C MangialavoriJuan Pablo F C Rossi
Oct 12, 1999·The American Journal of Physiology·M L WuK C Chu
Oct 9, 2002·The Journal of Biological Chemistry·Jason I E BruceTrevor J Shuttleworth

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