Linked Life Data

11920439

Source:http://linkedlifedata.com/resource/pubmed/id/11920439

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2002-3-28
pubmed:abstractText
In previous studies we have shown that light-induced cis/trans isomerization of the azobenzene moiety in cyclo-[Ala-Cys-Ala-Thr-Cys-Asp-Gly-Phe-AMPB] [AMPB: (4-aminomethyl)phenylazobenzoic acid] leads both in the monocyclic and in the oxidized bicyclic form to markedly differentiated conformational states in DMSO, a fact that lends itself for photomodulation of the redox potential of such bis-cysteinyl-peptides. For this purpose water-soluble systems are required, and this was achieved by replacing three residues outside the Cys-Ala-Thr-Cys active-site motif of thioredoxin reductase with lysines. The resulting cyclo-[Lys-Cys-Ala-Thr-Cys-Asp-Lys-Lys-AMPB] fully retains its photoresponsive properties in water as well assessed by uv and CD measurements. Paralleling results of the previously investigated azobenzene-containing cyclic peptides, the trans --> cis isomerization of the water-soluble monocyclic and oxidized bicyclic peptide is accompanied by a marked transition from a well-defined conformation to an ensemble of possible conformations. However, the conformational preferences are very dissimilar from those of the DMSO-soluble peptides. In fact, hydrogen bonds as well as secondary structure elements were found that change in the mono- and bicyclic peptide upon irradiation. The photo switch between different turn types and hydrogen bonding networks offers the structural rational for the significantly differentiated redox potentials, but also the possibility of monitoring by femtosecond uv-vis and ir spectroscopy fast and ultra fast backbone rearrangement processes following the electronic trans --> cis isomerization.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0006-3525
pubmed:author
pubmed:copyrightInfo
Copyright 2002 Wiley Periodicals, Inc.
pubmed:issnType
Print
pubmed:volume
63
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
382-93
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Photomodulation of conformational states. III. Water-soluble bis-cysteinyl-peptides with (4-aminomethyl) phenylazobenzoic acid as backbone constituent.
pubmed:affiliation
Max-Planck-Institut für Biochemie, 82152 Martinsried, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't