title: Root growth-promoting activity of unsaturated oligomeric uronates from alginate on carrot and rice plants.
abstract: The root elongation activity of unsaturated oligomeric uronates from alginate on carrot and rice plants was investigated. Unsaturated oligomeric uronates were prepared by digesting polymannuronate (PM) and polyguluronate (PG) with an alginate lyase purified from Pseudoalteromonas sp. strain No. 272. The root elongation activity was measured by elongation in length of carrot- and rice-excised root incubated in the B5-medium containing 0.8% agar in the dark. PM and PG showed no activity, but the enzymatic digestion mixtures of PG had promoting activity on roots of both plants at a final concentration of 0.5 mg/ml. The maximum activity was obtained at 0.75 mg/ml. The dependence of activity on degree of polymerization of the uronates was tested and the pentamer was most active, but the mechanism of the action of unsaturated uronates on the cells remains to be solved.
authors.affiliation: Division of Biochemistry, Faculty of Fisheries, Nagasaki University, Japan.
authors.forename: Xu
authors.initials: X
authors.lastname: Xu
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Iwamoto
authors.forename: Yoshie
authors.initials: Y
authors.lastname: Kitamura
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Oda
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Muramatsu
mesh_terms: D000464:Alginates / Q000737:chemistry* / Q000378:metabolism; D001704:Biopolymers / Q000096:biosynthesis / Q000737:chemistry / Q000494:pharmacology; D003470:Culture Media; D018552:Daucus carota / Q000187:drug effects / Q000254:growth & development*; D004305:Dose-Response Relationship, Drug; D020723:Glucuronic Acid / Q000737:chemistry* / Q000378:metabolism; D006603:Hexuronic Acids / Q000737:chemistry* / Q000378:metabolism; D012275:Oryza / Q000187:drug effects / Q000254:growth & development*; D018517:Plant Roots / Q000187:drug effects* / Q000254:growth & development*; D011133:Polysaccharide-Lyases / Q000378:metabolism; D031161:Pseudoalteromonas / Q000201:enzymology; D012639:Seeds / Q000187:drug effects / Q000254:growth & development; D013997:Time Factors; D014574:Uronic Acids / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D000464:Alginates; D001704:Biopolymers; D003470:Culture Media; D006603:Hexuronic Acids; D014574:Uronic Acids; D020723:Glucuronic Acid; D011133:Polysaccharide-Lyases; C016158:poly(beta-D-mannuronate) lyase