+ Site Statistics
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on LinkedInFollow on LinkedIn

+ Translate

Iron regulation and pathogenicity in Erwinia chrysanthemi 3937: role of the Fur repressor protein

Iron regulation and pathogenicity in Erwinia chrysanthemi 3937: role of the Fur repressor protein

Molecular Plant-Microbe Interactions 12(2): 119-128

Low iron availability is a triggering signal for coordinated expression of the genes encoding pectate lyases PelB, PelC, PelD, and PelE, and chrysobactin iron transport functions, which are two main determinants of phytopathogenicity of the Erwinia chrysanthemi strain 3937. The possible implication of the ferric uptake regulation (Fur) protein in this process was investigated. The E. chrysanthemi fur gene was cloned by functional complementation of an Escherichia coli fur mutant and sequenced. The 444-bp open reading frame identified was found to code for a protein highly similar to the E. coli Fur regulator. An E. chrysanthemi fur null mutant was constructed by reverse genetics. This mutant showed altered growth capacity and reduced pathogenicity on African violets. In a fur background, transcriptional lacZ fusions to genes belonging to the E. chrysanthemi high affinity iron transport systems were constitutively expressed. Transcription of the pelA, pelD, and pelE genes was analyzed, using fusions to the uidA reporter gene. Iron availability and a fur mutation did not influence the expression of pelA. In the presence of iron, pelD and pelE transcription levels were higher in the fur mutant than in the parental strain. Furthermore, iron deficiency stimulated the expression of both fusions in the fur mutant. These findings indicate that, in E. chrysanthemi 3937, (i) Fur negatively controls iron transport and genes encoding PelD and PelE, and (ii) additional factor(s) mediate iron regulation of the pel genes.

(PDF emailed within 0-6 h: $19.90)

Accession: 010885323

Download citation: RISBibTeXText

PMID: 9926414

DOI: 10.1094/MPMI.1999.12.2.119

Related references

Regulation and role in pathogenicity of Erwinia chrysanthemi 3937 pectin methylesterase. Journal of Bacteriology 171(7): 4085-4087, 1989

Iron as a modulator of pathogenicity of Erwinia chrysanthemi 3937 on Saintpaulia ionantha. Advances in molecular genetics of plant microbe interactions Vol 1 Proceedings of the 5th international symposium on the molecular genetics of plant microbe interactions, Interlaken, Switzerland, September 9-14, 1990: 94-98, 1991

Essential role of superoxide dismutase on the pathogenicity of Erwinia chrysanthemi strain 3937. Molecular Plant-Microbe Interactions 14(6): 758-767, 2001

The role of individual pectate lyases of erwinia chrysanthemi strain 3937 in pathogenicity on saintpaulia plants. Physiological & Molecular Plant Pathology 33(1): 95-104, 1988

Role of motility and chemotaxis in the pathogenesis of Dickeya dadantii 3937 (ex Erwinia chrysanthemi 3937). Microbiology 155(Pt 2): 434-442, 2009

Dynamic regulation of GacA in type III secretion, pectinase gene expression, pellicle formation, and pathogenicity of Dickeya dadantii (Erwinia chrysanthemi 3937). Molecular Plant-Microbe Interactions 21(1): 133-142, 2007

Differential role of ferritins in iron metabolism and virulence of the plant-pathogenic bacterium Erwinia chrysanthemi 3937. Journal of Bacteriology 190(5): 1518-1530, 2008

Flavohaemoglobin HmpX: a new pathogenicity determinant in Erwinia chrysanthemi strain 3937. Microbiology 141: 863-871, 1995

Analysis of three clustered polygalacturonase genes in Erwinia chrysanthemi 3937 revealed an anti-repressor function for the PecS regulator. Molecular Microbiology 34(4): 641-650, 1999

Coupling of iron assimilation and pectinolysis in Erwinia chrysanthemi 3937. Molecular Plant-Microbe Interactions 15(11): 1181-1191, 2002

The GacA global regulator is required for the appropriate expression of Erwinia chrysanthemi 3937 pathogenicity genes during plant infection. Environmental Microbiology 10(3): 545-559, 2008

Differential regulation by iron of Erwinia chrysanthemi pectate lyases: pathogenicity of iron transport regulatory (cbr) mutants. Molecular Plant Microbe Interactions 7(1): 71-77, 1994

The roles of indole-3-acetic acid (IAA) biosynthetic gene iaaM on pleiotropic phenotypes and pathogenicity of Erwinia chrysanthemi 3937. Abstracts of the General Meeting of the American Society for 105): 73-74, 2005