Pathovar-specific requirement for the Pseudomonas syringae lemA gene in disease lesion formation
| Autor: | S S Hirano, J J Rich, D K Willis |
|---|---|
| Rok vydání: | 1992 |
| Předmět: |
Mutant
Bacterial Toxins Locus (genetics) Applied Microbiology and Biotechnology Peptides Cyclic Microbiology Pseudomonas Sequence Homology Nucleic Acid Endopeptidases Pseudomonas syringae Plant Diseases Plants Medicinal Ecology biology Base Sequence Halo blight Fabaceae biology.organism_classification Phenotype Pathovar Genes Bacterial Mutation Restriction fragment length polymorphism Food Science Biotechnology Pseudomonadaceae Research Article |
| Zdroj: | Applied and environmental microbiology. 58(5) |
| ISSN: | 0099-2240 |
| Popis: | The lemA gene is conserved among strains and pathovars of Pseudomonas syringae. In P. syringae pv. syringae B728a, a causal agent of bacterial brown spot disese of bean, the lemA gene is required for lesion formation on leaves and pods. Using lemA-containing DNA as a probe, we determined that 80 P. syringae pv. syringae strains isolated from bean leaves could be grouped into seven classes based on restriction fragment length polymorphism. Marker exchange mutagenesis showed that the lemA gene was required for lesion formation by representative strains from each restriction fragment length polymorphism class. Hybridization to the lemA locus was detected within six different P. syringae pathovars and within Pseudomonas aeruginosa. Interestingly, a lemA homolog was present and functional within the nonpathogenic strain P. syringae Cit7. We cloned a lemA homolog from a genomic library of P. syringae pv. phaseolicola NPS3121, a causal agent of halo blight of bean, that restored lesion formation to a P. syringae pv. syringae lemA mutant. However, a lemA mutant P. syringae pv. phaseolicola strain retained the ability to produce halo blight disease symptoms on bean plants. Therefore, the lemA gene played an essential role in disease lesion formation by P. syringae pv. syringae isolates, but was not required for pathogenicity of a P. syringae pv. phaseolicola strain. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|