Distances between the functional sites of sarcoplasmic reticulum (Ca2+ + Mg2+)-ATPase and the lipid/water interface

Biochim Biophys Acta. 1986 Dec 16;863(2):178-84. doi: 10.1016/0005-2736(86)90257-9.

Abstract

Measurements of fluorescence energy transfer have been performed to determine the distance between the lipid-water interface and the ATP-binding site in the (Ca2+ + Mg2+)-ATPase from sarcoplasmic reticulum. The calculated distance between the donor, FITC bound to the protein (nucleotide binding-site marker), and the acceptor, rhodamine-5'-isothiocyanyldipalmitoylphosphatidylethanolamine (RITC-DPPE) incorporated in the membrane, was in the range of 34-42 A. In addition the distance between the high affinity Ca2+-binding sites and the lipid/water interface has been calculated by luminescence energy transfer from Tb3+ bound to the Ca2+ sites to RITC-DPPE included in the membrane, and it was approx. 10 A.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Binding Sites
  • Ca(2+) Mg(2+)-ATPase / metabolism*
  • Calcium / metabolism
  • Calcium-Transporting ATPases / metabolism*
  • Chemical Phenomena
  • Chemistry, Physical
  • Energy Transfer
  • Fluorescein-5-isothiocyanate
  • Fluoresceins
  • Fluorescent Dyes
  • Phosphatidylethanolamines
  • Rabbits
  • Rhodamines
  • Sarcoplasmic Reticulum / enzymology*
  • Terbium / metabolism
  • Thiocyanates

Substances

  • Fluoresceins
  • Fluorescent Dyes
  • Phosphatidylethanolamines
  • Rhodamines
  • Thiocyanates
  • Terbium
  • 1,2-dipalmitoyl-3-phosphatidylethanolamine
  • rhodamine isothiocyanate
  • Ca(2+) Mg(2+)-ATPase
  • Calcium-Transporting ATPases
  • Fluorescein-5-isothiocyanate
  • Calcium