Document Detail

Quantification of the amount of galacturonic acid residues in blocksequences in pectin homogalacturonan by enzymatic fingerprinting with exo- and endo-polygalacturonase II from Aspergillus niger.
MedLine Citation:
PMID:  10945680     Owner:  NLM     Status:  MEDLINE    
A method to determine the amount of galacturonic acid in blocksequence (BS) in pectin homogalacturonan (HG) is described. The method is based on a combination of endopolygalacturonase II (endo-PG II) and exopolygalacturonase (exo-PG) digestion followed by quantification of the liberated galacturonic acid monomer. The amount of monomers released is directly related to the amount of non-esterified galacturonic acid units located between two other non-esterified galacturonic acids units on the HG chain. The amount released for exo-PG digestion only corresponds to the BS located at the non-reducing end of the polymer. The difference between total- and exo-BS was calculated to be the amount of endo-BS located either within or on the reducing end of the HG. Three series of model pectins obtained by de-esterification of a high-ester pectin with either plant pectin methyl-esterase (p-PME, P-series), fungal pectin methyl-esterase (f-PME, F-series) and chemical de-esterification using base (B-series) were analysed and compared with a fully de-esterified pectic acid sample obtained from the same raw material. Clear differences for the increase of the amounts of blocksequence could be seen between de-esterification of the P- and F-series samples supporting a blockwise and a homogenous de-esterification mechanism, respectively. f-PME and base treatment showed only minor differences in the increase of galacturonic acid units in BS, despite differences seen in their methyl-esterification pattern. Differences between the amounts of galacturonic acid located in exo- and endo-BS, provided evidence for the need of a certain start side or blocklength for p-PME to de-esterify blockwise.
G Limberg; R Körner; H C Buchholt; T M Christensen; P Roepstorff; J D Mikkelsen
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Carbohydrate research     Volume:  327     ISSN:  0008-6215     ISO Abbreviation:  Carbohydr. Res.     Publication Date:  2000 Jul 
Date Detail:
Created Date:  2000-12-15     Completed Date:  2000-12-15     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0043535     Medline TA:  Carbohydr Res     Country:  NETHERLANDS    
Other Details:
Languages:  eng     Pagination:  321-32     Citation Subset:  IM    
Danisco Biotechnology, Copenhagen K, Denmark.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Aspergillus niger / enzymology*
Carbohydrate Conformation
Carbohydrate Sequence
Hexuronic Acids / analysis*
Models, Molecular
Molecular Sequence Data
Pectins / chemistry*,  metabolism*
Polygalacturonase / metabolism*
Reg. No./Substance:
0/Hexuronic Acids; 0/Pectins; 14982-50-4/galacturonic acid; 9046-38-2/polygalacturonic acid; EC 3.2.1.-/endopolygalacturonase II; EC

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Analysis of pectic epitopes recognised by hybridoma and phage display monoclonal antibodies using de...
Next Document:  Interaction between carbohydrate residues of alpha1-acid glycoprotein (orosomucoid) and saturating c...