TY  - JOUR
A1  - Schuler, Benjamin
A1  - Lipman, Everett A.
A1  - Steinbach, P. J.
A1  - Kumke, Michael Uwe
A1  - Eaton, W. A.
T1  - Polyproline and the "spectroscopic ruler" revisited with single-molecule fluorescence
N2  - To determine whether Forster resonance energy transfer (FRET) measurements can provide quantitative distance information in single-molecule fluorescence experiments on polypeptides, we measured FRET efficiency distributions for donor and acceptor dyes attached to the ends of freely diffusing polyproline molecules of various lengths. The observed mean FRET efficiencies agree with those determined from ensemble lifetime measurements but differ considerably from the values expected from Forster theory, with polyproline treated as a rigid rod. At donor-acceptor distances much less than the Forster radius R-o, the observed efficiencies are lower than predicted, whereas at distances comparable to and greater than R-0, they are much higher. Two possible contributions to the former are incomplete orientational averaging during the donor lifetime and, because of the large size of the dyes, breakdown of the point-dipole approximation assumed in Forster theory. End-to-end distance distributions and correlation times obtained from Langevin molecular dynamics simulations suggest that the differences for the longer polyproline peptides can be explained by chain bending, which considerably shortens the donor-acceptor distances
Y1  - 2005
SN  - 0027-8424
ER  - 
TY  - JOUR
A1  - Goetz, C.
A1  - Suopanki, J.
A1  - Schuler, Benjamin
A1  - Wanker, E.
A1  - Herrmann, Andreas
T1  - Perturbation of brain lipid membrane by soluble Huntingtin depends on its polyproline tract
Y1  - 2005
SN  - 0006-3495
ER  - 
TY  - GEN
A1  - Schuler, Benjamin
A1  - Lipman, Everett A.
A1  - Steinbach, Peter J.
A1  - Kumke, Michael Uwe
A1  - Eaton, William A.
T1  - Polyproline and the "spectroscopic ruler" revisited with single-molecule fluorescence
N2  - To determine whether Förster resonance energy transfer (FRET) measurements can provide quantitative distance information in single-molecule fluorescence experiments on polypeptides, we measured FRET efficiency distributions for donor and acceptor dyes attached to the ends of freely diffusing polyproline molecules of various lengths. The observed mean FRET efficiencies agree with those determined from ensemble lifetime measurements but differ considerably from the values expected from Förster theory, with polyproline treated as a rigid rod. At donor–acceptor distances much less than the Förster radius R0, the observed efficiencies are lower than predicted, whereas at distances comparable to and greater than R0, they are much higher. Two possible contributions to the former are incomplete orientational averaging during the donor lifetime and, because of the large size of the dyes, breakdown of the point-dipole approximation assumed in Förster theory. End-to-end distance distributions and correlation times obtained from Langevin molecular dynamics simulations suggest that the differences for the longer polyproline peptides can be explained by chain bending, which considerably shortens the donor–acceptor distances.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 008 
KW  - Förster resonance energy transfer
KW  - molecular dynamics
KW  - polypeptide
KW  - FRET
Y1  - 2005
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-12229
ER  -