A Transcriptional Regulator of the LuxR-UhpA Family, FlcA, Controls Flocculation and Wheat Root Surface Colonization by 'Azospirillum brasilense' Sp7

Title
A Transcriptional Regulator of the LuxR-UhpA Family, FlcA, Controls Flocculation and Wheat Root Surface Colonization by 'Azospirillum brasilense' Sp7
Publication Date
1998
Author(s)
Pereg, Lily
Paquelin, Annick
Gounon, Pierre
Kennedy, Ivan R
Elmerich, Claudine
Type of document
Journal Article
Language
en
Entity Type
Publication
Publisher
American Phytopathological Society
Place of publication
United States of America
DOI
10.1094/MPMI.1998.11.3.177
UNE publication id
une:13313
Abstract
Genetic complementation of a spontaneous mutant, impaired in flocculation, Congo red binding, and colonization of root surface, led to the identification of a new regulatory gene in 'Azospirillum brasilense' Sp7, designated 'flcA'. The deduced amino acid sequence of 'flcA' shared high similarity with a family of transcriptional activators of the LuxR-UhpA family. The most significant match was with the AgmR protein, an activator for glycerol metabolism in 'Pseudomonas aeruginosa'. Derivatives of Sp7 resulting from site-directed Tn5 mutagenesis in the 'flcA' coding sequence were constructed by marker exchange. Characterization of the resulting mutant strains showed that 'flcA' controls the production of capsular polysaccharides, the flocculation process in culture, and the colonization of the root surface of wheat. This study provides new information on the genetic control of the mechanism of plant root colonization by 'Azospirillum'.
Link
Citation
Molecular Plant-Microbe Interactions, 11(3), p. 177-187
ISSN
1943-7706
0894-0282
Start page
177
End page
187

Files:

NameSizeformatDescriptionLink