Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:4.2.2.10 (PNL)
 341 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for the characterization of partially methyl-esterified enzymatic pectin digests is described. The sensitivities of several matrices, positive and negative ion modes and desalting techniques for these acidic oligosaccharides were compared. The most favorable results were obtained with a thin-layer preparation of a mixture of 2,4,6-trihydroxyacetophenone and nitrocellulose in the negative ion mode. Results are presented demonstrating the sensitive characterization of separated and unseparated high-ester pectin digests obtained after complete digestion using Aspergillus niger pectin lyase and the analysis of digests after chemical modification. In the case of unseparated digests, the analysis of methylation patterns is demonstrated. Oligomers with a degree of polymerization up to 40 were detected after enrichment of large oligomers by propan-2-ol precipitation.
 ...
PMID:Characterization of enzymatic pectin digests by matrix-assisted laser desorption/ionization mass spectrometry. 976 99

Esterified acid soluble pectins from flax (Linun usitatissimum L.) were degraded either with HCl or pectin lyase. Centrifugation and 2-propanol precipitation led to the isolation of two low molecular weight polygalacturonates after acid hydrolysis of pectins. However, after pectin lyase digestion and purification by size-exclusion HPLC, (1)H NMR analyses indicated that acetylated hairy regions, large methylated and acetylated oligogalacturonides together with small unsubstituted oligogalacturonides were produced. Thus, in a few steps, a panel of substituted neutral and acidic oligosaccharides was produced from a raw plant material. Such oligosaccharides could be useful for further fractionations such as chemical saponification and enzymatic removal of neutral sugar chains from the hairy regions. The procedures used for pectin extraction, for degradation, and for the purification of fragments seem appropriate for large-scale production of biologically active oligosaccharides from flax.
 ...
PMID:Methods for obtaining neutral and acid oligosaccharides from flax pectins. 1568 17