English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
 
 
DownloadE-Mail
  Characterization of inside-out oriented H+-ATPases in cholate-pretreated renal brush-border membrane vesicles

Simon, B. J., & Burckhardt, G. (1990). Characterization of inside-out oriented H+-ATPases in cholate-pretreated renal brush-border membrane vesicles. Journal of Membrane Biology, 117(2), 141-151. doi:10.1007/BF01868681.

Item is

Basic

show hide
Genre: Journal Article

Files

show Files

Locators

show

Creators

show
hide
 Creators:
Simon, Bernd J.1, Author              
Burckhardt, Gerhard1, Author              
Affiliations:
1Department of Physiology, Max Planck Institute of Biophysics, Max Planck Society, ou_2068297              

Content

show
hide
Free keywords: proximal tubule; brush border; H+-ATPase; vacuolar
 Abstract: Exposure of porcine renal brush-border membrane vesicles to 1.2% cholate and subsequent detergent removal by dialysis reorients almost all N-ethylmaleimide (NEM)-sensitive ATPases from the vesicle inside to the outside. ATP addition to cholate-pretreated, but not to intact, vesicles causes H+ uptake as visualized by the delta pH indicator, acridine orange. The reoriented H+-pump is electrogenic because permeant extravesicular anions or intravesicular K+ plus valinomycin enhance H+ transport. ATP stimulates H+ uptake with an apparent Km of 93 microM. Support of H+ uptake and Pi liberation by ATP greater than GTP approximately ITP greater than UTP indicates a preference for ATP and utilization of other nucleotides at lower efficiency. ADP is a potent, competitive inhibitor of ATP-driven H+ uptake (Ki, 24 microM), Mg2+ and Mn2+ support ATP-driven H+ uptake, but Ca2+, Ba2+, and Zn2+ do not, 1 mM Zn2+ inhibits MgATP-driven H+ transport completely. NEM-sensitive Pi liberation is stimulated by Mg2+ and Mg2+ and, unlike H+ uptake, also by Ca2+ suggesting Ca2+-dependent ATP hydrolysis unrelated to H+ transport. The inside-out oriented H+-pump is relatively insensitive toward oligomycin, azide, N,N'-dicyclohexylcarbodiimide (DCCD) and vanadate, but efficiently inhibited by NEM (apparent Ki, 0.77 microM), and 4-chloro-7-nitro-benzoxa-1,3-diazole (NBD-Cl; apparent Ki, 0.39 microM). Taken together, the H+-ATPase of proximal tubular brush-border membranes exhibits characteristics very similar to those of "vacuolar type" (V-type) H+-ATPases. Hence, V-type H+-ATPases occur not only in intracellular organelles but also in specialized plasma membrane areas.

Details

show
hide
Language(s): eng - English
 Dates: 1990-02-221989-10-181990-08-01
 Publication Status: Published in print
 Pages: 11
 Publishing info: -
 Table of Contents: -
 Rev. Type: Peer
 Identifiers: DOI: 10.1007/BF01868681
PMID: 2145439
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: Journal of Membrane Biology
  Other : J. Membr. Biol.
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: New York : Springer-Verlag New York
Pages: - Volume / Issue: 117 (2) Sequence Number: - Start / End Page: 141 - 151 Identifier: ISSN: 0022-2631
CoNE: https://pure.mpg.de/cone/journals/resource/954925415943