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Coupling of iron assimilation and pectinolysis in Erwinia chrysanthemi 3937
- Source :
- Molecular Plant-Microbe Interactions, Molecular Plant-Microbe Interactions, American Phytopathological Society, 2002, 15 (11), pp.1181-91. ⟨10.1094/MPMI.2002.15.11.1181⟩, Molecular Plant-Microbe Interactions 11 (15), 1181–1191. (2002), Molecular Plant-Microbe Interactions, 2002, 15 (11), pp.1181-91. ⟨10.1094/MPMI.2002.15.11.1181⟩
- Publication Year :
- 2002
- Publisher :
- HAL CCSD, 2002.
-
Abstract
- International audience; Two major virulence determinants of the plant-pathogenic enterobacterium Erwinia chrysanthemi strain 3937 are the production of pectate lyase enzymes that degrade plant cell walls and expression of two high-affinity iron uptake systems mediated by two structurally unrelated siderophores, chrysobactin and achromobactin. Low iron availability is a signal that triggers transcription of the genes encoding pectate lyases PelD and PelE as well as that of genes involved in iron transport. This metalloregulation is mediated by the transcriptional repressor Fur. In this study, we analyzed the molecular mechanisms of this control. We purified the Erwinia chrysanthemi Fur protein. Band shift assays showed that Fur specifically binds in vitro to the regulatory regions of the genes encoding the ferrichrysobactin outer membrane receptor Fct and the pectate lyases PelD and PelE. We identified the Fur-binding sites of these promoter regions by performing DNase I footprinting experiments. From these data, we propose that Fur could inhibit the activation of the pelD and pelE genes by the cAMP receptor protein CRP according to an anti-activation mechanism. To identify other possible effectors involved in this control, we screened a bank of insertion mutants for an increase in transcriptional activity of pelD and fct genes in response to iron limitation. We isolated a mutant affected in the kdgK gene encoding the 2-keto-3-deoxygluconate (KDG) kinase, an enzyme involved in pectin catabolism. The growth of this mutant in the presence of pectic compounds led to a constitutive expression of iron transport genes as well as complete derepression of the pectinolysis genes. This effect was caused by intracellular accumulation of KDG. However, the derepression of iron transport genes by KDG does not involve the KdgR regulator of pectinolysis genes, which uses KDG as inducer. Thus, in Erwinia chrysanthemi, iron depletion or presence of KDG induces transcription of the genes involved in iron assimilation and pectinolysis. These important pathogenicity functions are coregulated by responding to common signals encountered in planta.
- Subjects :
- MESH: Signal Transduction
Siderophore
Physiology
MESH: Polysaccharide-Lyases
Pectobacterium chrysanthemi
Siderophores
MESH: Base Sequence
MESH: Virulence
fer
iron
MESH: Plant Diseases
MESH: Dipeptides
Cell Wall
Citrates
MESH: Bacterial Proteins
Derepression
Regulator gene
MESH: Receptors, Cell Surface
0303 health sciences
MESH: Gene Expression Regulation, Bacterial
MESH: Iron
Virulence
MESH: Gluconates
General Medicine
Dipeptides
MESH: Transcription Factors
[SDV.BBM.BC]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biomolecules [q-bio.BM]
Phosphotransferases (Alcohol Group Acceptor)
Biochemistry
protéine
MESH: Repressor Proteins
Pectate lyase
plante
Ketoglutaric Acids
Pectins
genetic
metabolism
dipeptide
pectobacterium chrysanthemi
phosphotransferase
signal transduction
plant science
protein
POLYSACCHARIDE
génétique
phosphotransférase
transcription
Bacterial Outer Membrane Proteins
Protein Binding
Signal Transduction
MESH: Mutation
Molecular Sequence Data
erwinia chrysanthemi
Receptors, Cell Surface
Biology
Gluconates
MESH: Sequence Homology, Nucleic Acid
Iron assimilation
03 medical and health sciences
MESH: Cell Wall
Bacterial Proteins
Sequence Homology, Nucleic Acid
MESH: Protein Binding
[SDV.BBM.BC]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biochemistry [q-bio.BM]
MESH: Siderophores
Gene
métabolisme
FUR
030304 developmental biology
Plant Diseases
Polysaccharide-Lyases
pectine
Binding Sites
MESH: Molecular Sequence Data
Base Sequence
030306 microbiology
MESH: Ketoglutaric Acids
metalloregulator
MESH: Bacterial Outer Membrane Proteins
Dickeya chrysanthemi
Gene Expression Regulation, Bacterial
MESH: Pectobacterium chrysanthemi
MESH: Phosphotransferases (Alcohol Group Acceptor)
Repressor Proteins
cAMP receptor protein
MESH: Binding Sites
Mutation
biology.protein
MESH: Citrates
Agronomy and Crop Science
MESH: Pectins
Transcription Factors
Subjects
Details
- Language :
- English
- ISSN :
- 08940282
- Database :
- OpenAIRE
- Journal :
- Molecular Plant-Microbe Interactions, Molecular Plant-Microbe Interactions, American Phytopathological Society, 2002, 15 (11), pp.1181-91. ⟨10.1094/MPMI.2002.15.11.1181⟩, Molecular Plant-Microbe Interactions 11 (15), 1181–1191. (2002), Molecular Plant-Microbe Interactions, 2002, 15 (11), pp.1181-91. ⟨10.1094/MPMI.2002.15.11.1181⟩
- Accession number :
- edsair.doi.dedup.....6f1c2725d3bb8b7c3c59a11246034f99