Biomaterial Database

Screening for hetero-transglycosylating activities in extracts from nasturtium (Tropaeolum majus). 2006

Fairouz Ait Mohand, and Vladimír Farkas

Institute of Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 84538 Bratislava, Slovakia.

Using combinations of different polysaccharides as glycosyl donors and of oligosaccharides fluorescently labeled by sulforhodamine (SR) as glycosyl acceptors, we screened for the presence of transglycosylating activities in extracts from nasturtium (Tropaeolum majus). Besides xyloglucan endotransglycosylase/hydrolase (XTH/XET, EC 2.4.1.207) activity, which transfers xyloglucanosyl residues from xyloglucan (XG) to XG-derived oligosaccharides (XGOs), a glycosyl transfer from XG to SR-labeled cellooligosaccharides and laminarioligosaccharides has been detected. The XGOs also served as acceptors for the glycosyl transfer from soluble cellulose derivatives carboxymethyl cellulose and hydroxyethylcellulose. The effectivity of these polysaccharides as glycosyl donors for transfer to XG-derived octasaccharide [1-3H]XXLGol decreased in the order XG > HEC > CMC. Isoelectric focusing in polyacrylamide gels showed that bands corresponding to hetero-transglycosylase activities coincided with zones corresponding to XTH/XET. These results can be explained as due either to substrate non-specificity of certain isoenzymes of XTH/XET or to existence of enzymes catalyzing a hetero-transfer, that is the formation of covalent linkages between different types of carbohydrate polymers.

UI	MeSH Term	Description	Entries
D010936	Plant Extracts	Concentrated pharmaceutical preparations of plants obtained by removing active constituents with a suitable solvent, which is evaporated away, and adjusting the residue to a prescribed standard.	Herbal Medicines,Plant Extract,Extract, Plant,Extracts, Plant,Medicines, Herbal
D011134	Polysaccharides	Long chain polymeric CARBOHYDRATES composed of MONOSACCHARIDES linked by glycosidic bonds.	Glycan,Glycans,Polysaccharide
D005453	Fluorescence	The property of emitting radiation while being irradiated. The radiation emitted is usually of longer wavelength than that incident or absorbed, e.g., a substance can be irradiated with invisible radiation and emit visible light. X-ray fluorescence is used in diagnosis.
D012680	Sensitivity and Specificity	Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)	Specificity,Sensitivity,Specificity and Sensitivity
D016695	Glycosyltransferases	Enzymes that catalyze the transfer of glycosyl groups to an acceptor. Most often another carbohydrate molecule acts as an acceptor, but inorganic phosphate can also act as an acceptor, such as in the case of PHOSPHORYLASES. Some of the enzymes in this group also catalyze hydrolysis, which can be regarded as transfer of a glycosyl group from the donor to water. Subclasses include the HEXOSYLTRANSFERASES; PENTOSYLTRANSFERASES; SIALYLTRANSFERASES; and those transferring other glycosyl groups. EC 2.4.	Glycosyltransferase,Glycoside Transferases,Transferases, Glycoside
D032388	Tropaeolum	A plant genus of the family TROPAEOLACEAE. The common nasturtium is a plant that grows 2.4-3.6 m (8-12 feet) tall and has funnel-shaped flowers that are commonly yellow-orange with red spots or stripes and have a long spur that contains sweet nectar. Some species in this genus are called watercress which is also a common name for RORIPPA and NASTURTIUM.	Cress, Indian,Nasturtium, Garden,Tropaeolum majus,Garden Nasturtium,Garden Nasturtiums,Indian Cress,Nasturtiums, Garden,Tropaeolums