Unravelling the secondary metabolome and biocontrol potential of the recently described species Bacillus nakamurai.

In the prospect of novel potential biocontrol agents, a new strain BDI-IS1 belonging to the recently described Bacillus nakamurai was selected for its strong in vitro antimicrobial activities against a range of bacterial and fungal phytopathogens. Genome mining coupled with metabolomics revealed that BDI-IS1 produces multiple non-ribosomal secondary metabolites including surfactin, iturin A, bacillaene, bacillibactin and bacilysin, together with some some ribosomally-synthesized and post-translationally modified peptides (RiPPs) such as plantazolicin, and potentially amylocyclicin, bacinapeptin and LCI. Reverse genetics further showed the specific involvement of some of these compounds in the antagonistic activity of the strain.

Biosynthesis of the antioxidant γ-glutamyl-cysteine with engineered Yarrowia lipolytica.

The dipeptide γ-glutamylcysteine (γ-GC), the first intermediate of glutathione (GSH) synthesis, is considered as a promising drug to reduce or prevent plethora of age-related disorders such as Alzheimer and Parkinson diseases. The unusual γ-linkage between the two constitutive amino acids, namely cysteine and glutamate, renders its chemical synthesis particularly challenging. Herein, we report on the metabolic engineering of the non-conventional yeast Yarrowia lipolytica for efficient γ-GC synthesis.

Bacillus velezensis BE2 controls wheat and barley diseases by direct antagonism and induced systemic resistance.

Wheat and barley rank among the main crops cultivated on a global scale, providing the essential nutritional foundation for both humans and animals. Nevertheless, these crops are vulnerable to several fungal diseases, such as Septoria tritici blotch and net blotch, which significantly reduce yields by adversely affecting leaves and grain quality. To mitigate the effect of these diseases, chemical fungicides have proven to be genuinely effective; however, they impose a serious environmental burden.

Lipopeptides as rhizosphere public goods for microbial cooperation.

Here, we provide new insights into the possible fate of cyclic lipopeptides as prominent specialized metabolites from beneficial bacilli and pseudomonads once released in the soil. Our data illustrate how the lipopeptidome may be enzymatically remodeled by as important members of the soil bacterial community. The enzymatic arsenal of enables an unsuspected extensive degradation of these compounds, allowing the bacterium to feed on these exogenous products via a mechanism going beyond linearization, which was previously reported as a detoxification strategy.

Pectic homogalacturonan sensed by acts as host associated cue to promote establishment and persistence in the rhizosphere.

isolates are among the most promising plant-associated beneficial bacteria used as biocontrol agents. However, various aspects of the chemical communication between the plant and these beneficials, determining root colonization ability, remain poorly described. Here we investigated the molecular basis of such interkingdom interaction occurring upon contact between and its host via the sensing of pectin backbone homogalacturonan (HG).

lipopeptide-mediated biocontrol of peanut stem rot caused by .

Introduction: Peanut ( L.) is a widespread oilseed crop of high agricultural importance in tropical and subtropical areas. It plays a major role in the food supply in the Democratic Republic of Congo (DRC).

Plant-associated Bacillus mobilizes its secondary metabolites upon perception of the siderophore pyochelin produced by a Pseudomonas competitor.

Bacillus velezensis is considered as model species for plant-associated bacilli providing benefits to its host such as protection against phytopathogens. This is mainly due to the potential to secrete a wide range of secondary metabolites with specific and complementary bioactivities. This metabolite arsenal has been quite well defined genetically and chemically but much remains to be explored regarding how it is expressed under natural conditions and notably how it can be modulated upon interspecies interactions in the competitive rhizosphere niche.

If All Else Fails: Impact of Silicon Accumulation in Maize Leaves on Volatile Emissions and Oviposition Site Selection of Spodoptera exigua Hübner.

Silicon (Si) fertilization alleviates biotic stresses in plants. Si enhances plant resistance against phytophagous insects through physical and biochemical mechanisms. In particular, Si modifies jasmonic acid levels and the emissions of herbivore-induced plant volatiles (HIPVs).

Relationship between lipopeptide biosurfactant and primary metabolite production by Bacillus strains in solid-state and submerged fermentation.

The relationship between lipopeptide and primary metabolite production by Bacillus spp. in solid-state fermentation (SSF) and submerged fermentation (SmF) was evaluated. Four wild-type strains and one mutant strain (unable to develop biofilm) were assessed in SSF and SmF, using a defined medium and polyurethane foam as inert support for SSF.

Rapid visualization of lipopeptides and potential bioactive groups of compounds by combining ion mobility and MALDI imaging mass spectrometry.

Mass spectrometry imaging (MSI) has become a powerful method for mapping metabolite distribution in a tissue. Applied to bacterial colonies, MSI has a bright future, both for the discovery of new bioactive compounds and for a better understanding of bacterial antibiotic resistance mechanisms. Coupled with separation techniques such as ion mobility mass spectrometry (IM-MS), the identification of metabolites directly on the image is now possible and does not require additional analysis such as HPLC-MS/MS.

Lipopeptide Interplay Mediates Molecular Interactions between Soil Bacilli and Pseudomonads.

Some species, such as B. velezensis, are important members of the plant-associated microbiome, conferring protection against phytopathogens. However, our knowledge about multitrophic interactions determining the ecological fitness of these biocontrol bacteria in the competitive rhizosphere niche is still limited.

Surfactin Stimulated by Pectin Molecular Patterns and Root Exudates Acts as a Key Driver of the -Plant Mutualistic Interaction.

Bacillus velezensis is considered as a model species belonging to the so-called Bacillus subtilis complex that evolved typically to dwell in the soil rhizosphere niche and establish an intimate association with plant roots. This bacterium provides protection to its natural host against diseases and represents one of the most promising biocontrol agents. However, the molecular basis of the cross talk that this bacterium establishes with its natural host has been poorly investigated.

Cyclic Lipopeptides Iturin and Fengycin Control Rice Blast Caused by in Potting and Acid Sulfate Soils by Direct Antagonism and Induced Systemic Resistance.

Rice monoculture in acid sulfate soils (ASSs) is affected by a wide range of abiotic and biotic constraints, including rice blast caused by To progress towards a more sustainable agriculture, our research aimed to screen the biocontrol potential of indigenous spp. against blast disease by triggering induced systemic resistance (ISR) via root application and direct antagonism. Strains belonging to the and group could protect rice against blast disease by ISR.

Effect of brine concentration on physico-chemical characteristics, texture, rheological properties and proteolysis level of cheeses produced by an optimized wild cardoon rennet.

The main objective of this study was to test the efficiency of a wild cardoon () rennet, previously optimized by response surface methodology, in cheese making process; then to select the best brine concentration, leading to excellent cheese quality. Results showed that the optimized rennet and chymosin produced curds with similar properties (yield, colour, texture, viscoelasticity), suggesting that this coagulant could replace successfully calf rennet. After brining at different salt concentrations (5, 7, 10 and 15%), we concluded that the use of 15% of salt in brine was an efficient way to reduce considerably the proteolysis level in cheeses, stored for 28 d at 4 °C.

Biosurfactants in Plant Protection Against Diseases: Rhamnolipids and Lipopeptides Case Study.

Biosurfactants are amphiphilic surface-active molecules that are produced by a variety of microorganisms including fungi and bacteria. , , and species are known to secrete rhamnolipids and lipopeptides that are used in a wide range of industrial applications. Recently, these compounds have been studied in a context of plant-microbe interactions.

Cyclic lipopeptide-producing Pseudomonas koreensis group strains dominate the cocoyam rhizosphere of a Pythium root rot suppressive soil contrasting with P. putida prominence in conducive soils.

Pseudomonas isolates from tropical environments have been underexplored and may form an untapped reservoir of interesting secondary metabolites. In this study, we compared Pseudomonas and cyclic lipopeptide (CLP) diversity in the rhizosphere of a cocoyam root rot disease (CRRD) suppressive soil in Boteva, Cameroon with those from four conducive soils in Cameroon and Nigeria. Compared with other soils, Boteva andosols were characterized by high silt, organic matter, nitrogen and calcium.

In Yarrowia lipolytica erythritol catabolism ends with erythrose phosphate.

In response to osmotic stress, the yeast Yarrowia lipolytica produces erythritol, a four-carbon sugar alcohol, from erythrose-P, an intermediate of the pentose phosphate pathway. Under non-stressing conditions (isotonic environment), the produced erythritol is subsequently recycled into erythrose-P that can feed the pentose phosphate pathway. Herein, gene YALI0F01584g was characterized as involved in the erythritol catabolic pathway.

Rapid Visualization of Chemically Related Compounds Using Kendrick Mass Defect As a Filter in Mass Spectrometry Imaging.

Kendrick mass defect (KMD) analysis is widely used for helping the detection and identification of chemically related compounds based on exact mass measurements. We report here the use of KMD as a criterion for filtering complex mass spectrometry data set. The method allow automated, easy and efficient data processing, enabling the reconstruction of 2D distributions of families of homologous compounds from MSI images.

Astin C Production by the Endophytic Fungus Cyanodermella asteris in Planktonic and Immobilized Culture Conditions.

The fungal endophyte Cyanodermella asteris (C. asteris) has been recently isolated from the medicinal plant Aster tataricus (A. tataricus).

Lipopeptide biodiversity in antifungal Bacillus strains isolated from Algeria.

Several Bacillus strains have been well studied for their ability to control soil-borne plant diseases. This property is linked to the production of several families of lipopeptides. Depending of their structure, these compounds show antifungal and/or plant systemic resistance inducing activities.

Influence of the ripening stage and the lyophilization of wild cardoon flowers on their chemical composition, enzymatic activities of extracts and technological properties of cheese curds.

The selection of an appropriate Cynara cardunculus flowers batch is a preliminary step to produce rennet with better clotting properties. For this reason, we proposed to study the influence of the ripening stage and the lyophilization of cardoon flowers on their chemical composition, enzymatic activities of extracts, and technological properties of cheese curds. Results of flowers composition have shown that lyophilized flowers harvested at the middle of ripening stage (A) could be employed to produce mainly proteins or milk-clotting proteases.

Stimulation of Fengycin-Type Antifungal Lipopeptides in in the Presence of the Maize Fungal Pathogen .

Most isolates belonging to the subsp. clade retain the potential to produce a vast array of structurally diverse antimicrobial compounds that largely contribute to their efficacy as biocontrol agents against numerous plant fungal pathogens. In that context, the role of cyclic lipopeptides (CLPs) has been well-documented but still little is known about the impact of interactions with other soil-inhabiting microbes on the expression of these molecules.

Genetic engineering of the branched fatty acid metabolic pathway of Bacillus subtilis for the overproduction of surfactin C isoform.

Surfactin, a lipopeptide produced by Bacillus subtilis, is one of the most powerful biosurfactants known. This molecule consists of a cyclic heptapeptide linked to a β-hydroxy fatty acid chain. The isomery and the length of the fatty acid (FA) chain are responsible for the surfactin's activities.