help button home button Biophys. J.
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Geibel, S.
Right arrow Articles by Fendler, K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Geibel, S.
Right arrow Articles by Fendler, K.

Biophys J, September 2000, p. 1346-1357, Vol. 79, No. 3

P3-[2-(4-hydroxyphenyl)-2-oxo]ethyl ATP for the Rapid Activation of the Na+,K+-ATPase

Sven Geibel,* Andreas Barth,dagger Sabine Amslinger,Dagger Andreas H. Jung,Dagger Christiane Burzik,* Ronald J. Clarke,* Richard S. Givens,Dagger and Klaus Fendler*

 *Max-Planck-Institut für Biophysik, D-60596 Frankfurt/Main, Germany;  dagger Institut für Biophysik, Johann Wolfgang Goethe-Universität, D-60590 Frankfurt/Main, Germany; and  Dagger Department of Chemistry, University of Kansas, Lawrence, Kansas 66045 USA

P3-[2-(4-hydroxyphenyl)-2-oxo]ethyl ATP (pHP-caged ATP) has been investigated for its application as a phototrigger for the rapid activation of electrogenic ion pumps. The yield of ATP after irradiation with a XeCl excimer laser (lambda  = 308 nm) was determined at pH 6.0-7.5. For comparison, the photolytic yields of P3-[1-(2-nitrophenyl)]ethyl ATP (NPE-caged ATP) and P3-[1,2-diphenyl-2-oxo]ethyl ATP (desyl-caged ATP) were also measured. It was shown that at lambda  = 308 nm pHP-caged ATP is superior to the other caged ATP derivatives investigated in terms of yield of ATP after irradiation. Using time-resolved single-wavelength IR spectroscopy, we determined a lower limit of 106 s-1 for the rate constant of release of ATP from pHP-caged ATP at pH 7.0. Like NPE-caged ATP, pHP-caged ATP and desyl-caged ATP bind to the Na+,K+-ATPase and act as competitive inhibitors of ATPase function. Using pHP-caged ATP, we investigated the charge translocation kinetics of the Na+,K+-ATPase at pH 6.2-7.4. The kinetic parameters obtained from the electrical measurements are compared to those obtained with a technique that does not require caged ATP, namely parallel stopped-flow experiments using the voltage-sensitive dye RH421. It is shown that the two techniques yield identical results, provided the inhibitory properties of the caged compound are taken into account. Our results demonstrate that under physiological (pH 7.0) and slightly basic (pH 7.5) or acidic (pH 6.0) conditions, pHP-caged ATP is a rapid, effective, and biocompatible phototrigger for ATP-driven biological systems.

Biophys J, September 2000, p. 1346-1357, Vol. 79, No. 3
© 2000 by the Biophysical Society   0006-3495/00/09/1346/12  $2.00


This article has been cited by other articles:


Home page
 Biophys. JHome page
L. Zhang, R. Buchet, and G. Azzar
Phosphate Binding in the Active Site of Alkaline Phosphatase and the Interactions of 2-Nitrosoacetophenone with Alkaline Phosphatase-Induced Small Structural Changes
Biophys. J., June 1, 2004; 86(6): 3873 - 3881.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2000 by the Biophysical Society.