Wavelength-selective fluorescence in ion channels formed by gramicidin A in membranes

Chattopadhyay, Amitabha ; Rawat, Satinder S (2007) Wavelength-selective fluorescence in ion channels formed by gramicidin A in membranes Journal of Chemical Sciences, 119 (2). pp. 135-140. ISSN 0253-4134

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Official URL: http://www.ias.ac.in/chemsci/Pdf-Mar2007/135-140.p...

Related URL: http://dx.doi.org/10.1007/s12039-007-0020-x


Gramicidins are linear peptides that form ion channels that are specific for monovalent cations in membranes. The tryptophan residues in the gramicidin channel play a crucial role in the organization and function of the channel. The natural mixture of gramicidins, denoted as gramicidin A', consists of mostly gramicidin A, but also contains gramicidins B, C and D as minor components. We have previously shown that the tryptophan residues in ion channels formed by the naturally occurring peptide, gramicidin A', display wavelength-dependent fluorescence characteristics due to the motionally restricted environment in which they are localized. In order to check the influence of ground-state heterogeneity in the observed wavelength-selective fluorescence of gramicidin A' in membranes, we performed similar experiments with pure gramicidin A in model membranes. Our results show that the observed wavelength-selective fluorescence characteristics of naturally occurring gramicidin A' are not due to ground-state heterogeneity.

Item Type:Article
Source:Copyright of this article belongs to Indian Academy of Sciences.
Keywords:Gramicidins; Ion Channels; Wavelength-dependent Fluorescence; Wavelength-selective Fluorescence; Red-edge Excitation Shift
ID Code:6982
Deposited On:26 Oct 2010 04:50
Last Modified:16 May 2016 17:14

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