SwePub
Sök i LIBRIS databas

  Extended search

onr:"swepub:oai:DiVA.org:su-8211"
 

Search: onr:"swepub:oai:DiVA.org:su-8211" > Probing Dynamics of...

  • 1 of 1
  • Previous record
  • Next record
  •    To hitlist
  • Ghalebani, LeilaStockholms universitet,Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi (author)

Probing Dynamics of Oligosaccharides by Interference Phenomena in NMR Relaxation

  • BookEnglish2008

Publisher, publication year, extent ...

  • Stockholm :Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi,2008
  • 73 s.
  • electronicrdacarrier

Numbers

  • LIBRIS-ID:oai:DiVA.org:su-8211
  • ISBN:9789171557148
  • https://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-8211URI

Supplementary language notes

  • Language:English
  • Summary in:English

Part of subdatabase

Classification

  • Subject category:vet swepub-contenttype
  • Subject category:dok swepub-publicationtype

Notes

  • Oligosaccharides (carbohydrates) are a large class of biological molecules that are important as energy sources in the human body and have enormously varied biological functions. It is generally believed that biological activities of carbohydrates are related to their internal dynamics. The dynamic properties of some oligosaccharides in solution are studied in this thesis, by NMR relaxation. We have employed relaxation interference effects to investigate the conformational dynamics within oligosaccharides (in-tramolecular dynamics) and paramagnetic relaxation enhancement (PRE) as an experimental tool to study intermolecular dynamics. Most of the thesis concerns the dynamics of the methylene group in the two possibly mobile parts of the oligosaccharide: in the exocyclic hydroxymethyl moiety and in the glycosidic linkage position. To perform conformational dynamic studies, the more traditional auto-relaxation pa-rameters are combined with the relaxation interference terms or the cross-correlated relaxation rates (CCRRs). Some experimental schemes based on the initial-rate technique were developed for measuring CCRRs. The techniques are useful for labelled sugars as well as naturally abundant ones. Furthermore, various dynamical models ranging from the Lipari–Szabo approach to several more informative and complicated models such as the two-site jump model, restricted internal rotation and slowly relaxing local structure (SRLS), have been employed to interpret our experimental data. We have combined and com-pared different models; we have also developed a novel approach to existing models, by scaling dipolar coupling constants (DCC), to extract the dynamic behaviour and structural properties of the system. We found that the auto- and cross-correlated relaxation data analyses yield a consistent picture of the dynam-ics in all cases. Additionally, our investigations show that CCRRs are practically important for verifica-tion of certain dynamical and structural information that is difficult to be determined by other means. Moreover, the anisotropy of the carbon-13 chemical shielding tensor in the methylene group has been estimated, using the interference between dipole-dipole and chemical shift anisotropy.This thesis also discusses using the PRE to investigate sugar dynamics relative to a paramagnetic MRI contrast agent in solution, which might be important in medicine. We have studied the intramolecu-lar dynamics of the trisaccharide raffinose in the presence of a gadolinium complex. We also investigated the effect of translational diffusion instead of rotational diffusion, which is normally more important in NMR. The paramagnetically enhanced spin–lattice relaxation rates of aqueous protons over a wide range of magnetic fields and of carbon-13 and protons of the sugar at high fields have been measured. The nuclear magnetic relaxation dispersion of water protons and the PREs of proton and carbon in the sugar are interpreted in terms of the model recently developed in our laboratory, allowing both outer- and inner-sphere PREs for water protons, but allowing only the outer sphere PRE for nuclei in the sugar. We found that the relative diffusion has a stronger effect on the PRE than the electron spin relaxation.

Subject headings and genre

Added entries (persons, corporate bodies, meetings, titles ...)

  • Kowalewski, Jozef,ProfessorStockholms universitet,Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi (thesis advisor)
  • Mueller, Norbert,ProfessorJuhannes kepler University (opponent)
  • Stockholms universitetInstitutionen för fysikalisk kemi, oorganisk kemi och strukturkemi (creator_code:org_t)

Internet link

Find in a library

To the university's database

  • 1 of 1
  • Previous record
  • Next record
  •    To hitlist

Find more in SwePub

By the author/editor
Ghalebani, Leila
Kowalewski, Joze ...
Mueller, Norbert ...
About the subject
MEDICAL AND HEALTH SCIENCES
MEDICAL AND HEAL ...
and Basic Medicine
and Other Basic Medi ...
By the university
Stockholm University

Search outside SwePub

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Close

Copy and save the link in order to return to this view