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 Kusba, J.
Right arrow Articles by Lakowicz, J. R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Kusba, J.
Right arrow Articles by Lakowicz, J. R.

Biophys J, March 2002, p. 1358-1372, Vol. 82, No. 3

Lateral Diffusion Coefficients in Membranes Measured by Resonance Energy Transfer and a New Algorithm for Diffusion in Two Dimensions

Jósef Kusba,* Li Li,dagger Ignacy Gryczynski,dagger Grzegorz Piszczek,dagger Michael Johnson,dagger and Joseph R. Lakowiczdagger

 *Technical University of Gdansk, Faculty of Applied Physics and Mathematics, Gdansk, Poland, and  dagger University of Maryland School of Medicine, Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, Baltimore, Maryland 21201 USA

We describe measurements of lateral diffusion in membranes using resonance energy transfer. The donor was a rhenium (Re) metal-ligand complex lipid, which displays a donor decay time near 3 µs. The long donor lifetime resulted in an ability to measure lateral diffusion coefficient below 10-8 cm2/s. The donor decay data were analyzed using a new numerical algorithm for calculation of resonance energy transfer for donors and acceptors randomly distributed in two dimensions. An analytical solution to the diffusion equation in two dimensions is not known, so the equation was solved by the relaxation method in Laplace space. This algorithm allows the donor decay in the absence of energy transfer to be multiexponential. The simulations show that mutual lateral diffusion coefficients of the donor and acceptor on the order of 10-8 cm2/s are readily recovered from the frequency-domain data with donor decay times on the microsecond timescale. Importantly, the lateral diffusion coefficients and acceptor concentrations can be recovered independently despite correlation between these parameters. This algorithm was tested and verified using the donor decays of a long lifetime rhenium lipid donor and a Texas red-lipid acceptor. Lateral diffusion coefficients ranged from 4.4 × 10-9 cm2/s in 1,2-dimyristoyl-sn-glycero-3-[phospho-rac-(1-glycerol)] (DMPG) at 10°C to 1.7 × 10-7 cm2/s in 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) at 35°C. These results demonstrated the possibility of direct measurements of lateral diffusion coefficients using microsecond decay time luminophores.

Biophys J, March 2002, p. 1358-1372, Vol. 82, No. 3
© 2002 by the Biophysical Society   0006-3495/02/03/1358/15  $2.00


This article has been cited by other articles:


Home page
 Biophys. JHome page
C. Mazzuca, L. Stella, M. Venanzi, F. Formaggio, C. Toniolo, and B. Pispisa
Mechanism of Membrane Activity of the Antibiotic Trichogin GA IV: A Two-State Transition Controlled by Peptide Concentration
Biophys. J., May 1, 2005; 88(5): 3411 - 3421.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2002 by the Biophysical Society.