title: Influence of ultraviolet-C on the compositions of cell-wall polysaccharides and carbohydrase activities of Silene vulgaris callus.
abstract: UV-C irradiation (254 nm) was found to enhance the secretion of some cell-wall-degrading enzymes, especially the following carbohydrases: beta-galactosidase, alpha-L-arabinofuranosidase, polygalacturonase, pectinesterase, cellulase, xylanase, and beta-xylosidase, in the campion callus, contributing thereby to an alteration in the polysaccharide structure. The relative amounts of the galactose and arabinose residues in pectin (silenan) and of arabinose in arabinogalactan of calli irradiated during the exponential phase were shown to decrease during the stationary phase. A decrease in the degree of SV methylesterification was found for the irradiated callus. These alterations were found to persist over a long period of culturing time. Decreasing the relative amounts of the arabinose residues in arabinogalactan and pectin and the galactose residues in silenan corresponded to increasing activity of alpha-L-arabinofuranosidase and beta-galactosidase, respectively, due to treatment with UV-C. UV-C irradiation may be used as a tool for modifying the structural features of the cell-wall polysaccharides, such as the relative amounts of galactose and arabinose residues in the side chains of polysaccharides, with the purpose of obtaining physiologically active polysaccharides with the desired properties and structural features.
authors.affiliation: Institute of Physiology, Komi Science Centre, The Urals Branch of the Russian Academy of Sciences, 50, Pervomaiskaya str., 167982 Syktyvkar, Russia. gunter@physiol.komisc.ru
authors.forename: Elena A
authors.initials: EA
authors.lastname: Günter
authors.forename: Olga M
authors.initials: OM
authors.lastname: Kapustina
authors.forename: Oxana V
authors.initials: OV
authors.lastname: Popeyko
authors.forename: Yury S
authors.initials: YS
authors.lastname: Ovodov
mesh_terms: D002473:Cell Wall / Q000201:enzymology / Q000378:metabolism / Q000528:radiation effects*; D004789:Enzyme Activation / Q000528:radiation effects; D005685:Galactans / Q000378:metabolism; D006026:Glycoside Hydrolases / Q000378:metabolism*; D010368:Pectins / Q000378:metabolism; D011134:Polysaccharides / Q000737:chemistry / Q000378:metabolism*; D029751:Silene / Q000378:metabolism / Q000528:radiation effects*; D046509:Tissue Culture Techniques; D014466:Ultraviolet Rays
chemical_list: D005685:Galactans; D011134:Polysaccharides; D010368:Pectins; D006026:Glycoside Hydrolases; C019822:carbohydrase; C005653:arabinogalactan