Linked Life Data

20452631

Source:http://linkedlifedata.com/resource/pubmed/id/20452631

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2010-6-1
pubmed:abstractText
The raffinose family oligosaccharides (RFOs), including raffinose (Gal-alpha(1-->6)-Glc-alpha(1-->2)beta-Fru), stachyose (Gal-alpha(1-->6)-Gal-alpha(1-->6)-Glc-alpha(1-->2)beta-Fru) and higher degree of polymerization RFOs are the most widespread galactosyl-oligosaccharides (GOS) in the plant kingdom. Stellaria media is a typical representative of the Caryophyllaceae, a plant family lacking stachyose and the typical galactosyl extensions of stachyose. During cold treatment raffinose, lychnose (Gal-alpha(1-->6)-Glc-alpha(1-->2)beta-Fru-alpha(1-->1)-Gal) and stellariose (Gal-alpha(1-->6)-[Gal-alpha(1-->4)]-Glc-alpha(1-->2)beta-Fru-alpha(1-->1)-Gal) were found to accumulate in S. media stems. Next to these prominent oligosaccharides, two extra GOS were discovered. Biochemical analyses (enzymatic incubations and mild acid hydrolysis) and mass spectrometry identified the first, most abundant oligosaccharide as Glc-alpha(1-->2)beta-Fru-alpha(1-->1)-Gal, a breakdown product of lychnose. The structure of this trisaccharide was confirmed by full NMR characterization. The second, less abundant compound (termed mediose) was identified as Gal-alpha(1-->6)-[Gal-alpha(1-->4)]Glc-alpha(1-->2)beta-Fru after biochemical analyses. By partial enzyme purification the presence of discrete lychnose synthase (raffinose:raffinose 1(Fru) galactosyltransferase) and stellariose synthase (raffinose:lychnose 4(Glc) galactosyltransferase) activities were shown. A model is presented explaining the structural diversity of GOS in S. media. In the absence of stachyose, raffinose is further elongated by lychnose synthase and stellariose synthase to produce lychnose, mediose and stellariose. Most likely, these compounds are also subject to partial trimming by endogenous alpha-galactosidases.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
1873-3700
pubmed:author
pubmed:copyrightInfo
2010 Elsevier Ltd. All rights reserved.
pubmed:issnType
Electronic
pubmed:volume
71
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1095-103
pubmed:dateRevised
2011-1-10
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Metabolism of galactosyl-oligosaccharides in Stellaria media--discovery of stellariose synthase, a novel type of galactosyltransferase.
pubmed:affiliation
Laboratory of Molecular Plant Physiology, Institute of Botany and Microbiology, K.U.Leuven, Kasteelpark Arenberg 31 (2434), B-3001 Heverlee, Belgium.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't