Wound induced plant phenolic compounds and virulence gene expression in Agrobacterium species
department or school: Science, Faculty of
department or school: Botany, Department of
data provider: DSpace
degree campus: UBCV
creator: Spencer, Paul Anthony
issued: 2011-02-28T23:26:42Z
issued: 1991
related degree: Doctor of Philosophy - PhD
degree grantor: University of British Columbia
description: Crown gall disease of plants is caused by introduction of foreign DNA into susceptible plant cells by strains of Agrobacterium tumefaciens. The expression of bacterial virulence genes is triggered by chemicals present in plant wound exudates. The exudates contain a number of phenolic compounds which act as chemical signals inducing expression of a number of genes directing the DNA transfer process. These are the virulence or vir genes, and vir::lac reporter gene fusions have been widely used to assay vir gene induction in Agrobacterium tumefaciens strains. Using such strains to monitor vir gene expression, Stachel et al. (1985) isolated from Nicotiana tabacum two active acetophenones: 3,5-dimethoxy-4-hydroxyacetophenone, ("acetosyringone" or AS), and α-hydroxy-3,5-dimethoxy-4-hydroxy-acetophenone, ("hydroxyacetosyringone" or HO-AS). However, in vitro assay results suggested that other more common compounds also exhibited activity (Spencer and Towers, 1988). This analysis of structure-activity relationships of induced vir expression in A. tumefaciens was presented in a previous thesis (Paul Spencer, M.Sc. thesis). The results revealed that a variety of commonly occurring plant phenolic compounds were capable of activating vir genes. In addition to the acetophenones, a variety of benzoic and cinnamic acid derivatives, and even a few chalcones of appropriate ring substitution were active. This thesis reports the isolation and identification of a number of these compounds in plant wound exudates. Some Agrobacterium tumefaciens strains are restricted in host range to certain grapevine cultivars. Subsequent to the development of a convenient and sensitive plate-bioassay method, a strongly active component in grapevine wound exudates was purified. A newly described vir-inducing phenolic compound was isolated from a number of Vitis cultivars using gel filtration, thin layer and high pressure liquid chromatographies. This was identified as syringic acid methyl ester (3,5-dim…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/31872
note: W O U N D I N D U C E D P L A N T P H E N O L I C C O M P O U N D S A N D V I R U L E N C E G E N E E X P R E S S I O N I N A G R O B A C T E R I U M SPECIES by P A U L A N T H O N Y S P E N C E R B.Sc , The University of Victoria, 1985 M . S c , The University of British Columbia , 1988 A THESIS S U B M I T T E D I N P A R T I A L F U L F I L L M E N T O F " ^ . T H E R E Q U I R E M E N T S FOR T H E D E G R E E O F D O C T O R O F P H I L O S O P H Y i n T H E F A C U L T Y O F G R A D U A T E STUDIES (Department of Botany) We accept this thesis as conforming to the required standard: T H E U N I V E R S I T Y O F BRITISH C O L U M B I A A p r i l 1991 © Paul Anthony Spencer, 1991 In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Department of The University of British Columbia Vancouver, Canada DE-6 (2/88) Abstract C r o w n gall disease of plants is caused by introduction of foreign D N A into susceptible plant cells by strains of Agrobacterium tumefaciens. The expression of bacterial virulence genes is triggered by chemicals present i n plant w o u n d exudates. The exudates contain a number of phenol ic compounds which act as chemical signals inducing expression of a number of genes directing the D N A transfer process. These are the virulence or vir genes, and virv.lac reporter gene fusions have been widely used to assay vir gene induct ion i n Agrobacterium tumefaciens strains. U s i n g such strains to monitor vir gene expression, Stachel et al. (1985) isolated from Nicotiana tabacum two active acetophe…
has type: Thesis/Dissertation
is shown at: 10.14288/1.0100896
language: eng
degree discipline: Botany
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/31872