ISSN:
0091-7419
Schlagwort(e):
13C-enriched carbohydrates
;
glycosyl phosphates
;
13C-NMR
;
carbohydrate conformations
;
Life Sciences
;
Molecular Cell Biology
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Biologie
,
Chemie und Pharmazie
,
Medizin
Notizen:
The application of 13C-NMR spectroscopy to problems involving the structures and interactions of carbohydrates is described. Both 13C-enriched and natural abundance compounds were used and some advantages of the use of the stable isotope are described. Carbon-carbon and carbon-proton coupling constants obtained from 1-13 C enriched carbohydrates were employed in the assignment of their chemical shifts and to establish solution conformation. In all cases studied thus far, C-3 couples to C-1 only in the β-anomers while C-5 couples to C-1 only in the α-anomers. C-6 and C-2 always couple to C-1 in both anomeric species. The alkaline degradation of glucose [1-13 C] to saccharinic acids was followed by 13C-NMR. The conversion of glucose [1-13 C] to fructose-1,6-bisphosphate [1,6-13 C] by enzymes of the glycolytic pathway was shown as an example of the use of 13C-enriched carbohydrates to elucidate biochemical pathways. In a large number of glycosyl phosphates the 31P to H-1 and 31P to C-2 coupling constants demonstrate that in the preferred conformation the phosphate group lies between the O-5 and the H-1 of the pyranose ring. The influence of paramagnetic Mn2+ ions on the proton decoupled 13C-NMR spectra of uridine diphosphate N-acetylglucosamine indicates that the Mn2+ interacts strongly with the pyrophosphate moiety and with the carbonyl groups of the uracil and N-acetyl groups.
Zusätzliches Material:
9 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/jss.400060407
Permalink
