Document Detail


Solvent dependence of the rotational diffusion of TOAC-spin-labeled alamethicin.
MedLine Citation:
PMID:  17589865     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Three derivatives of the hydrophobic, channel-forming peptaibiotic alamethicin (F50/5) have been synthesized, the original Aib residue at position 1, 8, or 16 being replaced with the spin-labeled amino acid TOAC (=2,2,6,6-tetramethylpiperidin-1-oxyl-4-amino-4-carboxylic acid). Electron-paramagnetic-resonance (EPR) spectroscopy was used to characterize the rotational diffusion of these compounds in five isotropic solvents of differing viscosity and polarity, including MeOH, EtOH, PrOH, i-PrOH, and hexanol (HxOH). In MeOH, the labeled alamethicins were found to rotate anisotropically as a monomer (axial ratio a/b=3). In aliphatic alcohols of increasing viscosity (and hydrophobicity), the rotational correlation times progressively increased. Even in HxOH, the (fivefold) increase in correlation time was no greater than the increase in viscosity. We conclude that TOAC-labeled alamethicins remain monomeric in these solvents of relatively high polarity.
Authors:
Derek Marsh; Micha Jost; Cristina Peggion; Claudio Toniolo
Related Documents :
18331845 - Molecular crowding effects on structure and stability of dna.
20617125 - Extension of the pna world by functionalized pna monomers eligible candidates for inver...
16061935 - An ultrasensitive photoelectrochemical nucleic acid biosensor.
17110475 - High-volume extraction of nucleic acids by magnetic bead technology for ultrasensitive ...
15560795 - Structural determination of the polar glycoglycerolipids from thermophilic bacteria mei...
20381565 - Long-chain 3-hydroxy fatty acids accumulating in lchad and mtp deficiencies induce oxid...
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Chemistry & biodiversity     Volume:  4     ISSN:  1612-1880     ISO Abbreviation:  Chem. Biodivers.     Publication Date:  2007 Jun 
Date Detail:
Created Date:  2007-06-28     Completed Date:  2007-07-17     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  101197449     Medline TA:  Chem Biodivers     Country:  Switzerland    
Other Details:
Languages:  eng     Pagination:  1269-74     Citation Subset:  IM    
Affiliation:
Max-Planck-Institut für biophysikalische Chemie, Abteilung Spektroskopie, Göttingen, Germany.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Alamethicin / chemistry*
Cyclic N-Oxides / chemistry*
Electron Spin Resonance Spectroscopy
Solvents / chemistry*
Spin Labels*
Chemical
Reg. No./Substance:
0/Cyclic N-Oxides; 0/Solvents; 0/Spin Labels; 15871-57-5/2,2,6,6-tetramethylpiperidine-N-oxide-4-amino-4-carboxylic acid; 27061-78-5/Alamethicin

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Conformational analysis of TOAC-labelled alamethicin F50/5 analogues.
Next Document:  Supramolecular structure of self-assembling alamethicin analog studied by ESR and PELDOR.