Indole Alkaloid Production by the Halo Blight Bacterium Treated with the Phytoalexin Genistein.

When pv. , the bacterium that causes halo blight, induces hypersensitive immunity in common bean leaves, salicylic acid and phytoalexins accumulate at the site of infection. Both salicylic acid and the phytoalexin resveratrol exert antibiotic activities and toxicities in vitro, adversely disrupting the pv.

Salicylic Acid and Phytoalexin Induction by a Bacterium that Causes Halo Blight in Beans.

pv. is a bacterium that causes halo blight in beans. Different varieties of beans have hypersensitive resistance to specific races of .

Bacterial Immobilization and Toxicity Induced by a Bean Plant Immune System.

pv. causes halo blight disease in the common bean . The bacterium invades the leaf apoplast and uses a type III secretion system to inject effector proteins into a bean cell to interfere with the bean immune system.

The Proteomics of Resistance to Halo Blight in Common Bean.

Halo blight disease of beans is caused by a gram-negative bacterium, pv. . The disease is prevalent in South America and Africa and causes crop loss for indigent people who rely on beans as a primary source of daily nutrition.

Benzothiadiazole Conditions the Bean Proteome for Immunity to Bean Rust.

The common bean rust fungus reduces harvests of the dry, edible common bean. Natural resistance genes in the plant can provide protection until a fungal strain that breaks resistance emerges. In this study, we demonstrate that benzo(1,2,3)thiadiazole-7-carbothioic acid -methyl ester (BTH) sprayed on susceptible beans induces resistance to common bean rust.

A Proteomic Network for Symbiotic Nitrogen Fixation Efficiency in Bradyrhizobium elkanii.

Rhizobia colonize legumes and reduce N to NH in root nodules. The current model is that symbiotic rhizobia bacteroids avoid assimilating this NH. Instead, host legume cells form glutamine from NH, and the nitrogen is returned to the bacteroid as dicarboxylates, peptides, and amino acids.

Protection Against Common Bean Rust Conferred by a Gene-Silencing Method.

Rust disease of the dry bean plant, Phaseolus vulgaris, is caused by the fungus Uromyces appendiculatus. The fungus acquires its nutrients and energy from bean leaves using a specialized cell structure, the haustorium, through which it secretes effector proteins that contribute to pathogenicity by defeating the plant immune system. Candidate effectors have been identified by DNA sequencing and motif analysis, and some candidates have been observed in infected leaves by mass spectrometry.

Putative Rust Fungal Effector Proteins in Infected Bean and Soybean Leaves.

The plant-pathogenic fungi Uromyces appendiculatus and Phakopsora pachyrhizi cause debilitating rust diseases on common bean and soybean. These rust fungi secrete effector proteins that allow them to infect plants, but their effector repertoires are not understood. The discovery of rust fungus effectors may eventually help guide decisions and actions that mitigate crop production loss.

Expression of a synthetic rust fungal virus cDNA in yeast.

Mycoviruses are viruses that infect fungi. Recently, mycovirus-like RNAs were sequenced from the fungus Phakopsora pachyrhizi, the causal agent of soybean rust. One of the RNAs appeared to represent a novel mycovirus and was designated Phakopsora pachyrhizi virus 2383 (PpV2383).

Disruption of Rpp1-mediated soybean rust immunity by virus-induced gene silencing.

Phakopsora pachyrhizi, a fungus that causes rust disease on soybean, has potential to impart significant yield loss and disrupt food security and animal feed production. Rpp1 is a soybean gene that confers immunity to soybean rust, and it is important to understand how it regulates the soybean defense system and to use this knowledge to protect commercial crops. It was previously discovered that some soybean proteins resembling transcription factors accumulate in the nucleus of Rpp1 soybeans.

Nuclear proteomic changes linked to soybean rust resistance.

Soybean rust, caused by the fungus Phakopsora pachyrhizi, is an emerging threat to the US soybean crop. In an effort to identify proteins that contribute to disease resistance in soybean we compared a susceptible Williams 82 cultivar to a resistant Williams 82 inbred isoline harboring the Rpp1 resistance gene (R-gene). Approximately 4975 proteins from nuclear preparations of leaves were detected using a high-throughput liquid chromatography-mass spectrometry method.

Generation of Phaseolus vulgaris ESTs and investigation of their regulation upon Uromyces appendiculatus infection.

Background: Phaseolus vulgaris (common bean) is the second most important legume crop in the world after soybean. Consequently, yield losses due to fungal infection, like Uromyces appendiculatus (bean rust), have strong consequences. Several resistant genes were identified that confer resistance to bean rust infection.

Quantitative proteomic analysis of bean plants infected by a virulent and avirulent obligate rust fungus.

Plants appear to have two types of active defenses, a broad-spectrum basal system and a system controlled by R-genes providing stronger resistance to some pathogens that break the basal defense. However, it is unknown if the systems are separate entities. Therefore, we analyzed proteins from leaves of the dry bean crop plant Phaseolus vulgaris using a high-throughput liquid chromatography tandem mass spectrometry method.

Tandem mass spectrometry for the detection of plant pathogenic fungi and the effects of database composition on protein inferences.

LC-MS/MS has demonstrated potential for detecting plant pathogens. Unlike PCR or ELISA, LC-MS/MS does not require pathogen-specific reagents for the detection of pathogen-specific proteins and peptides. However, the MS/MS approach we and others have explored does require a protein sequence reference database and database-search software to interpret tandem mass spectra.

Protein accumulation in the germinating Uromyces appendiculatus uredospore.

Uromyces appendiculatus is a rust fungus that causes disease on beans. To understand more about the biology of U. appendiculatus, we have used multidimensional protein identification technology to survey proteins in germinating asexual uredospores and have compared this data with proteins discovered in an inactive spore.

Shotgun identification of proteins from uredospores of the bean rust Uromyces appendiculatus.

We are interested in learning more about the proteome of Uromyces appendiculatus, the fungus that causes common bean rust. Knowledge of the proteins that differentiate life-cycle stages and distinguish infectious bodies such as uredospores, germlings, appressoria, and haustoria may be used to define host-pathogen interactions or serve as targets for chemical inhibition of the fungus. We have used 2-D nanoflowLC-MS/MS to identify more than 400 proteins from asexual uredospores.