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Pregled bibliografske jedinice broj: 204676

Theoretical study of the gas-phase structures of sodiated and cesiated leucine and isoleucine: zwitterionic structure disfavored in kinetic method experiments


Rožman, Marko
Theoretical study of the gas-phase structures of sodiated and cesiated leucine and isoleucine: zwitterionic structure disfavored in kinetic method experiments // Journal of mass spectrometry, 40 (2005), 10; 1357-1361 doi:10.1002/jms.926 (međunarodna recenzija, članak, znanstveni)


Naslov
Theoretical study of the gas-phase structures of sodiated and cesiated leucine and isoleucine: zwitterionic structure disfavored in kinetic method experiments

Autori
Rožman, Marko

Izvornik
Journal of mass spectrometry (1076-5174) 40 (2005), 10; 1357-1361

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Leucine ; isoleucine ; alkali metals ; gas-phase structure ; density functional theory ; kinetic method

Sažetak
Themost stable charge-solvated (CS) and zwitterionic (ZW) structures of sodiated and cesiated leucine and isoleucine were studied by density functional theorymethods. According to the Boltzmann distribution in gas phase, both forms of LeuNa+ and IleNa+ exist, but in LeuCs+ and IleCs+, the ZW forms are dominant. Results for the sodiated compounds are consistentwith the relationship found between decrease in relative stability of CS versus ZW form and aliphatic amino acid side chain length. The observed degeneracy in energy for IleNa+ conformers is at odds with kinetic method results. Additional calculations showed that kinetic method structural determinations for IleNa+ do not reflect relative order of populations in the lowest energy conformers. Since complexation of cationized amino acids into ion-bound dimers disfavors ZW structure by ∼ 8 kJmol− 1, it is suggested that for energy close conformers of sodium-cationized amino acids, the kinetic method may not be reliable for structural determinations.

Izvorni jezik
Engleski

Znanstvena područja
Kemija



POVEZANOST RADA


Projekt / tema
0098032

Ustanove
Institut "Ruđer Bošković", Zagreb

Autor s matičnim brojem:
Marko Rožman, (237562)

Časopis indeksira:


  • Current Contents Connect (CCC)
  • Web of Science Core Collection (WoSCC)
    • Science Citation Index Expanded (SCI-EXP)
    • SCI-EXP, SSCI i/ili A&HCI
  • Scopus
  • MEDLINE


Uključenost u ostale bibliografske baze podataka:


  • Chemical Abstracts


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