HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Antúnez-Lamas, M. Articles by Rodríguez-Palenzuela, P. Search for Related Content PubMed PubMed Citation Articles by Antúnez-Lamas, M. Articles by Rodríguez-Palenzuela, P. Agricola Articles by Antúnez-Lamas, M. Articles by Rodríguez-Palenzuela, P.

Role of motility and chemotaxis in the pathogenesis of Dickeya dadantii 3937 (ex Erwinia chrysanthemi 3937)

¹ Departamento de Biotecnología, Universidad Politécnica de Madrid, E.T.S. Ingenieros Agrónomos, CBGP, Centro de Biotecnología y Genómica de Plantas, Avda Complutense S/N, E-28040 Madrid, Spain
² CIFOR, Instituto Nacional Investigaciones Agrarias (INIA), C. Coruña km 7.5, 28040 Madrid, Spain
³ Departamento de Arquitectura de Computadores, E.T.S. de Ingeniería Informática, Campus de Teatinos, E-29071 Málaga, Spain

Correspondence
Pablo Rodríguez-Palenzuela
pablo.rpalenzuela{at}upm.es

Dickeya dadantii 3937 (ex Erwinia chrysanthemi), a member of the Enterobacteriaceae, causes soft rot in many economically important crops. A successful pathogen has to reach the interior of the plant in order to cause disease. To study the role of motility and chemotaxis in the pathogenicity of D. dadantii 3937, genes involved in the chemotactic signal transduction system (cheW, cheB, cheY and cheZ) and in the structure of the flagellar motor (motA) were mutagenized. All the mutant strains grew like the wild-type in culture media, and the production and secretion of pectolytic enzymes was not affected. As expected, the swimming ability of the mutant strains was reduced with respect to the wild-type: motA (94 %), cheY (80 %), cheW (74 %), cheB (54 %) and cheZ (48 %). The virulence of the mutant strains was analysed in chicory, Saintpaulia and potato. The mutant strains were also tested for their capability to enter into Arabidopsis leaves. All the mutants showed a significant decrease of virulence in certain hosts; however, the degree of virulence reduction varied depending on the virulence assay. The ability to penetrate Arabidopsis leaves was impaired in all the mutants, whereas the capacity to colonize potato tubers after artificial inoculation was affected in only two mutant strains. In general, the virulence of the mutants could be ranked as motA<cheY<cheB=cheW<cheZ, which correlated with the degree to which swimming was affected. These results clearly indicate that motility plays an important role in the pathogenicity of this bacterium.