NMR assignment of structural motifs in intact β-limit dextrin and its α-amylase degradation products in situ

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

An increasingly detailed and realistic view of biological processes often hinges on atomic-level characterization of biomacromolecules and of the processes they are involved in, preferably under near-physiological conditions. Structure, degradation, and synthesis of glucose storage polymers have been studied for decades with a range of analytical tools, but the detailed in situ analysis has remained an analytical challenge. Here, we report the NMR assignment of different structural motifs in the β-limit dextrin from lintnerized maize starch as a branched α-glucan model system for starch, which is depleted of repetitive α-(1→4) glycosidic bonds at non-reducing ends but has the α-(1→6) branch points intact. By NMR spectroscopy at 18.7T magnetic field, we assign 12 discernible α-glucopyranosyl spin systems and identify them with different structural motifs. Amylolysis of the β-limit dextrin is directly followed by real-time NMR spectroscopy and four major cleavage products are identified and assigned to different branch point structures. Overall, these NMR assignments facilitate in situ assays under realistic conditions of substrate competition, transglycosylation, and product inhibition and shed light on chemical shift tendencies in different structural motifs of branched α-glucans. © 2012 Elsevier Ltd. All rights reserved.
Original languageEnglish
JournalCARBOHYDRATE RESEARCH
Volume359
Pages (from-to)76-80
ISSN0008-6215
DOIs
Publication statusPublished - 2012
Externally publishedYes

Keywords

  • AMYLASES
  • CORN
  • CORN STARCH
  • DECOMPOSITION
  • DEGRADATION
  • DEXTRINS
  • GLUCANS
  • STARCH
  • STRUCTURE
  • α-AMYLASES

Fingerprint Dive into the research topics of 'NMR assignment of structural motifs in intact β-limit dextrin and its α-amylase degradation products in situ'. Together they form a unique fingerprint.

Cite this