title: Stimulation of indoleacetic acid production in a Rhizobium isolate of Vigna mungo by root nodule phenolic acids.
abstract: The influence of endogenous root nodules phenolic acids on indoleacetic acid (IAA) production by its symbiont (Rhizobium) was examined. The root nodules contain higher amount of IAA and phenolic acids than non-nodulated roots. Presence of IAA metabolizing enzymes, IAA oxidase, peroxidase, and polyphenol oxidase indicate the metabolism of IAA in the nodules and roots. Three most abundant endogenous root nodule phenolic acids (protocatechuic acid, 4-hydroxybenzaldehyde and p-coumaric acid) have been identified and their effects on IAA production by the symbiont have been studied in L-tryptophan supplemented yeast extract basal medium. Protocatechuic acid (1.5 microg ml(-1)) showed maximum stimulation (2.15-fold over control) of IAA production in rhizobial culture. These results indicate that the phenolic acids present in the nodule might serve as a stimulator for IAA production by the symbiont (Rhizobium).
authors.affiliation: Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, India.
authors.forename: Santi M
authors.initials: SM
authors.lastname: Mandal
authors.forename: Santi
authors.initials: S
authors.lastname: Mandal
authors.forename: Mahitosh
authors.initials: M
authors.lastname: Mandal
authors.forename: Amit K
authors.initials: AK
authors.lastname: Das
authors.forename: Amit
authors.initials: A
authors.lastname: Das
authors.forename: Bikas R
authors.initials: BR
authors.lastname: Pati
authors.forename: Bikas
authors.initials: B
authors.lastname: Pati
authors.forename: Ananta K
authors.initials: AK
authors.lastname: Ghosh
authors.forename: Ananta
authors.initials: A
authors.lastname: Ghosh
mesh_terms: D004156:Catechol Oxidase / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D003470:Culture Media; D007887:Fabaceae / Q000378:metabolism* / Q000382:microbiology; D062385:Hydroxybenzoates / Q000378:metabolism*; D007210:Indoleacetic Acids / Q000378:metabolism*; D010544:Peroxidases / Q000378:metabolism; D012231:Rhizobium / Q000378:metabolism*; D053204:Root Nodules, Plant / Q000378:metabolism* / Q000382:microbiology; D013559:Symbiosis
chemical_list: D003470:Culture Media; D062385:Hydroxybenzoates; D007210:Indoleacetic Acids; C009091:protocatechuic acid; C030737:indoleacetic acid; D004156:Catechol Oxidase; C027929:indoleacetic acid oxidase; D010544:Peroxidases; C017616:phenolic acid