Linked Life Data

19530667

Source:http://linkedlifedata.com/resource/pubmed/id/19530667

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
27
pubmed:dateCreated
2009-7-2
pubmed:abstractText
Dissociation kinetics of the K(+) loss reaction of three potassiated tertiary amino acids (Scheme 1) were studied by infrared multiple photon dissociation (IRMPD) in a Fourier transform ion cyclotron resonance (FT ICR)-MS instrument. The aim of the study was to probe if a kinetic study by IRMPD can yield useful information on the ion structure of the precursor ion species. The measured activation energy values determined by IRMPD are related to the potassium affinity, DeltaH(K(+)), of N-methyl proline determined by threshold collision-induced dissociation experiments. By appropriate scaling with this reference value, the experimentally determined activation energy values for the K(+) loss are transformed into respective potassium affinities, DeltaH(K(+))(IRMPD). These values match the calculated potassium affinity values for salt bridge (SB) structures, DeltaH(K(+))(SB), substantially better than those for canonical structures with a single formal charge site (charge solvation (CS)), thereby allowing structure identification. This conclusion is consistent with other spectroscopic data, which yielded unambiguous evidence of these tertiary amino acids adopting SB structures in the gas phase. This study demonstrates that IRMPD can be applied to determine individual ion structures in the gas phase, given that adequate reference values are available for proper scaling.
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Jul
pubmed:issn
1520-5215
pubmed:author
pubmed:issnType
Electronic
pubmed:day
9
pubmed:volume
113
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7779-83
pubmed:year
2009
pubmed:articleTitle
Kinetic determination of potassium affinities by IRMPD: elucidation of precursor ion structures.
pubmed:affiliation
Department of Chemistry, University of Cologne, Greinstrasse 4, 50939 Köln, Germany. mathias.schaefer@uni-koeln.de
pubmed:publicationType
Journal Article