help button home button Biophys. J.
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
Biophys. J. BioFAST: First Published August 12, 2005. doi:10.1529/biophysj.105.060798
© 2005 by the Biophysical Society.

A more recent version of this article appeared on November 1, 2005.
This Article
Right arrow Full Text (Rapid PDF)
Right arrow All Versions of this Article:
biophysj.105.060798v1
89/5/3049    most recent
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 Author home page(s):
Amitabha Chattopadhyay
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 Rawat, S. S
Right arrow Articles by Chattopadhyay, A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Rawat, S. S
Right arrow Articles by Chattopadhyay, A.

CHANNELS, RECEPTORS, AND ELECTRICAL SIGNALING

Effect of Structural Transition of the Host Assembly on Dynamics of an Ion Channel Peptide: A Fluorescence Approach

Satinder S Rawat 1, Devaki A Kelkar 1 and Amitabha Chattopadhyay 1*

1 Centre for Cellular & Molecular Biology

* To whom correspondence should be addressed. E-mail: amit{at}ccmb.res.in.

Submitted on February 6, 2005
Revised on March 21, 2005
Accepted on 25 July 2005


  Abstract
Structural transition can be induced in charged micelles by increasing the ionic strength of the medium. We have monitored the organization and dynamics of the functionally important tryptophan residues of gramicidin in spherical and rod-shaped SDS micelles utilizing a combination of wavelength-selective fluorescence and related fluorescence approaches. Our results show that tryptophans in gramicidin, present in the single stranded {beta}6.3 conformation, experience slow solvent relaxation giving rise to red edge excitation shift (REES) in spherical and rod-shaped micelles. In addition, changes in fluorescence polarization with increasing excitation or emission wavelength reinforce that the gramicidin tryptophans are localized in motionally restricted regions of these micelles. Fluorescence quenching experiments using acrylamide as a quencher of tryptophan fluorescence show that there is reduced water penetration in rod-shaped micelles. Taken together, we show that gramicidin conformation and dynamics is sensitive to the salt-induced structural transition in charged micelles. In addition, these results demonstrate that deformation of the host assembly could modulate protein conformation and dynamics.

Key Words: Gramicidin, Ion Channel, REES, SDS, Sphere-to-rod transition




This article has been cited by other articles:


Home page
 J BiochemHome page
N. Yoshida, T. Mita, and M. Onda
Susceptibilities of Phospholipid Membranes Containing Cholesterol or Ergosterol to Gramicidin and its Derivative Incorporated in Lysophospholipid Micelles
J. Biochem., August 1, 2008; 144(2): 167 - 176.
[Abstract] [Full Text] [PDF]

Home page
 Biophys. JHome page
A. Chattopadhyay, S. S. Rawat, D. V. Greathouse, D. A. Kelkar, and R. E. Koeppe II
Role of Tryptophan Residues in Gramicidin Channel Organization and Function
Biophys. J., July 1, 2008; 95(1): 166 - 175.
[Abstract] [Full Text] [PDF]

Home page
 Biophys. JHome page
H. Raghuraman and A. Chattopadhyay
Orientation and Dynamics of Melittin in Membranes of Varying Composition Utilizing NBD Fluorescence
Biophys. J., February 15, 2007; 92(4): 1271 - 1283.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
Copyright © 2005 by the Biophysical Society.