Linked Life Data

11349948

Source:http://linkedlifedata.com/resource/pubmed/id/11349948

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2001-5-14
pubmed:abstractText
The structures and stability of sodiated species of 8-Beta, a linear lipopeptide analog (beta-aminotetradecanoyl-NYNQPNS) of the antifungal peptide iturin A2, were evaluated by electrospray ionization mass spectrometry (ESI-MS). Association of the lipopeptide, 8-Beta, with sodium afforded protection from fragmentation at high cone voltages and increasing collision energy conditions in the ESI-MS. The order of decreasing stability was found as 8-Beta 1Na > 8-Beta 2Na > 8-Beta 3Na > 8-Beta. Substantial differences were found between fragmentation patterns of the free and sodiated molecular species. Breakage of the N-terminal peptide bond of L-Pro generated the major product ions of the free 8-Beta parent ion. Impaired fragmentation of the sodium adducts of 8-Beta, indicated that this bond is protected by sodium complexation. Fragmentation patterns of the sodiated lipopeptide further revealed two specific binding sites for a nonsolvated sodium ion within the two type II beta-turn sequences (beta-aminotetradecanoyl-NYN and QPNS) of the natural iturin A2. It is proposed that specific interaction with sodium takes place with most of the peptide bond oxygens in these turns, and with the Gln sidechain. This interaction leads to stabilized structures in which the peptide backbone, specifically the peptide bonds in which L-Pro participates, is protected against low-energy fragmentation during ESI-MS.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1044-0305
pubmed:author
pubmed:issnType
Print
pubmed:volume
12
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
505-16
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Sequence specific stabilization of a linear analog of the antifungal lipopeptide iturin A2 by sodium during low energy electrospray ionization mass spectrometry conditions.
pubmed:affiliation
Department of Biochemistry, University of Stellenbosch, Matieland, South Africa, Republic of South Africa, mra@maties.sun.ac.za
pubmed:publicationType
Journal Article