Entrapment of antimicrobial compounds in a metal matrix for crop protection.

Agricultural yields are often limited by damage caused by pathogenic microorganisms, including plant-pathogenic bacteria. The chemical control options to cope with bacterial diseases in agriculture are limited, predominantly relying on copper-based products. These compounds, however, possess limited efficacy.

Host-Driven Selection, Revealed by Comparative Analysis of Type III Secretion Effectoromes, Unveils Novel Recognized Effectors.

species are specialized plant pathogens, often exhibiting a narrow host range. They rely on the translocation of effector proteins through the type III secretion system to colonize their respective hosts. The effector arsenal varies among spp.

LC-MS/MS-based phospholipid profiling of plant-pathogenic bacteria with tailored separation of methyl-branched species.

Plant-pathogenic bacteria are one of the major constraints on agricultural yield. In order to selectively treat these bacteria, it is essential to understand the molecular structure of their cell membrane. Previous studies have focused on analyzing hydrolyzed fatty acids (FA) due to the complexity of bacterial membrane lipids.

Virulence-Related Assays for Investigation of the Acidovorax citrulli-Cucurbitaceae Pathosystem.

Acidovorax citrulli is one of the most important pathogens of cucurbit crops, mainly melon and watermelon. Although A. citrulli is able to infect all aerial parts of the plant, fruits are highly sensitive to the bacterium.

Natural variation in a short region of the Acidovorax citrulli type III-secreted effector AopW1 is associated with differences in cytotoxicity and host adaptation.

Bacterial fruit blotch, caused by Acidovorax citrulli, is a serious disease of melon and watermelon. The strains of the pathogen belong to two major genetic groups: group I strains are strongly associated with melon, while group II strains are more aggressive on watermelon. A.

Stable isotope analysis confirms substantial changes in the fatty acid composition of bacteria treated with antimicrobial random peptide mixtures (RPMs).

Resistance of plant-pathogenic bacteria to classic antibiotics has prompted the search for suitable alternative antimicrobial substances. One promising strategy could be the use of purposely synthesized random peptide mixtures (RPMs). Six plant-pathogenic bacteria were cultivated and treated with two RPMs previously found to show antimicrobial activity mainly by bacterial membrane disruption.

The GDSL-Lipolytic Enzyme Lip1 Is Required for Full Virulence of the Cucurbit Pathogenic Bacterium .

Bacterial fruit blotch caused by is a serious disease of cucurbit crops. Here we report characterization of a mutant strain of M6 defective in , a gene encoding a lipolytic enzyme. The M6- mutant was detected in a mutant library screen aimed at identifying M6 mutants with altered levels of twitching motility.

Secretion systems play a critical role in resistance to predation by Bdellovibrio bacteriovorus.

Bdellovibrio bacteriovorus, a Gram-negative predatory bacterium belonging to the Bdellovibrio and like organisms (BALOs), predates on Gram-negative bacteria. BALO strains differ in prey range but so far, the genetic basis of resistance against BALO predation is hardly understood. We developed a loss-of-function approach to screen for sensitive mutants in a library of strain M6, a predation-resistant strain of the plant pathogen Acidovorax citrulli.

Detailed analysis of the fatty acid composition of six plant-pathogenic bacteria.

Bacteria show distinct and characteristic fatty acid (FA) patterns which can be modified by environmental conditions. In this study, we cultivated six plant-pathogenic bacteria of agricultural concern and performed a detailed analysis of the fatty acid composition. The study covered four strains of the gram-negative Xanthomonas campestris pathovar (pv) campestris (Xcc), Xanthomonas perforans (Xp), Acidovorax citrulli (Ac) and Pseudomonas syringae pv.

Antibacterial lipo-random peptide mixtures exhibit high selectivity and synergistic interactions.

Random peptide mixtures (RPMs) have been recently proposed as powerful antimicrobial compounds. These are unique mixtures of peptides synthesized by random combination of a cationic and a hydrophobic amino acid. Here, we introduce a new type of antimicrobial compounds, short lipo-RPMs, which result from N-palmitoylation of RPMs.

Direct Binding of Salicylic Acid to -Acyl-Homoserine Lactone Synthase.

Salicylic acid (SA) is a hormone that mediates systemic acquired resistance in plants. We demonstrated that SA can interfere with group behavior and virulence of the soft-rot plant pathogen spp. through quorum sensing (QS) inhibition.

Genetically Distinct Strains Display Cucurbit Fruit Preference Under Field Conditions.

Strains of , the causal agent of bacterial fruit blotch (BFB) of cucurbits, can be assigned to two groups, I and II. The natural association of group I and II strains with different cucurbit species suggests host preference; however, there are no direct data to support this hypothesis under field conditions. Hence, the objective of this study was to assess differences in the prevalence of group I and II strains on cucurbit species in the field.

Potential Control of Potato Soft Rot Disease by the Obligate Predators and Like Organisms.

Bacterial soft rot diseases caused by spp. and spp. affect a wide range of crops, including potatoes, a major food crop.

Pathways to defense metabolites and evading fruit bitterness in genus Solanum evolved through 2-oxoglutarate-dependent dioxygenases.

The genus Solanum comprises three food crops (potato, tomato, and eggplant), which are consumed on daily basis worldwide and also producers of notorious anti-nutritional steroidal glycoalkaloids (SGAs). Hydroxylated SGAs (i.e.

iTRAQ-based proteomic analyses of the plant-pathogenic bacterium Acidovorax citrulli during entrance into and resuscitation from the viable but nonculturable state.

Acidovorax citrulli, the causal agent of bacterial fruit blotch (BFB) disease, infects cucurbit crops including watermelon and melon. This bacterium can enter the viable but nonculturable (VBNC) state following exposure to copper sulfate. Moreover, copper-induced VBNC A.

Show me your secret(ed) weapons: a multifaceted approach reveals a wide arsenal of type III-secreted effectors in the cucurbit pathogenic bacterium Acidovorax citrulli and novel effectors in the Acidovorax genus.

The cucurbit pathogenic bacterium Acidovorax citrulli requires a functional type III secretion system (T3SS) for pathogenicity. In this bacterium, as with Xanthomonas and Ralstonia spp., an AraC-type transcriptional regulator, HrpX, regulates expression of genes encoding T3SS components and type III-secreted effectors (T3Es).

Complete Assembly of the Genome of an Strain Reveals a Naturally Occurring Plasmid in This Species.

is the causal agent of bacterial fruit blotch (BFB), a serious threat to cucurbit crop production worldwide. Based on genetic and phenotypic properties, strains are divided into two major groups: group I strains have been generally isolated from melon and other non-watermelon cucurbits, while group II strains are closely associated with watermelon. In a previous study, we reported the genome of the group I model strain, M6.

Induction and Resuscitation of the Viable but Non-culturable (VBNC) State in , the Causal Agent of Bacterial Fruit Blotch of Cucurbitaceous Crops.

is a gram-negative bacterium that infects a wide range of cucurbits causing bacterial fruit blotch (BFB) disease. Copper-based compounds are the most widely-used chemicals for managing BFB and other bacterial diseases in the field. Many bacteria can enter a viable but non-culturable (VBNC) state in response to stress, including exposure to copper, and recover the culturability when favorable conditions return.

Nicotiana species as surrogate host for studying the pathogenicity of Acidovorax citrulli, the causal agent of bacterial fruit blotch of cucurbits.

Bacterial fruit blotch (BFB) caused by Acidovorax citrulli is one of the most important bacterial diseases of cucurbits worldwide. However, the mechanisms associated with A. citrulli pathogenicity and genetics of host resistance have not been extensively investigated.

Random peptide mixtures as new crop protection agents.

Many types of crops are severely affected by at least one important bacterial disease. Chemical control of bacterial plant diseases in the field vastly relies on copper-based bactericides, yet with limited efficacy. In this study, we explored the potential of two random peptide mixture (RPM) models as novel crop protection agents.

Association Between Loss of Type IV Pilus Synthesis Ability and Phenotypic Variation in the Cucurbit Pathogenic Bacterium Acidovorax citrulli.

Acidovorax citrulli is the causal agent of bacterial fruit blotch of cucurbits. We have shown that functional type IV pili (T4P) are required for full virulence of this bacterium. To identify A.

Silver Nanoparticles Complexed with Bovine Submaxillary Mucin Possess Strong Antibacterial Activity and Protect against Seedling Infection.

A simple method for the synthesis of nanoparticles (NPs) of silver (Ag) in a matrix of bovine submaxillary mucin (BSM) was reported previously by some of the authors of this study. Based on mucin characteristics such as long-lasting stability, water solubility, and surfactant and adhesive characteristics, we hypothesized that these compounds, named BSM-Ag NPs, may possess favorable properties as potent antimicrobial agents. The goal of this study was to assess whether BSM-Ag NPs possess antibacterial activity, focusing on important plant-pathogenic bacterial strains representing both Gram-negative ( and ) and Gram-positive () genera.

Carotenoid production and phenotypic variation in Azospirillum brasilense.

We assessed the occurrence of phenotypic variation in Azospirillum brasilense strains Sp7, Cd, Sp245, Az39 and phv2 during growth in rich media, screening for variants altered in colony pigmentation or extracellular polysaccharide (EPS) production. Previous studies showed that EPS-overproducing variants of Sp7 appear frequently following starvation or growth in minimal medium. In contrast, no such variants were detected during growth in rich media in the tested strains except for few variants of phv2.

Plant phenolic volatiles inhibit quorum sensing in pectobacteria and reduce their virulence by potential binding to ExpI and ExpR proteins.

Quorum sensing (QS) is a population density-dependent regulatory system in bacteria that couples gene expression to cell density through accumulation of diffusible signaling molecules. Pectobacteria are causal agents of soft rot disease in a range of economically important crops. They rely on QS to coordinate their main virulence factor, production of plant cell wall degrading enzymes (PCWDEs).

Insights from the Genome Sequence of Acidovorax citrulli M6, a Group I Strain of the Causal Agent of Bacterial Fruit Blotch of Cucurbits.

Acidovorax citrulli is a seedborne bacterium that causes bacterial fruit blotch of cucurbit plants including watermelon and melon. A. citrulli strains can be divided into two major groups based on DNA fingerprint analyses and biochemical properties.