Plasma membrane H pump at a crossroads of acidic and iron stresses in yeast-to-hypha transition.

Iron is an essential nutrient but is toxic in excess mainly under acidic conditions. Yeasts have emerged as low cost, highly efficient soil inoculants for the decontamination of metal-polluted areas, harnessing an increasing understanding of their metal tolerance mechanisms. Here, we investigated the effects of extracellular iron and acid pH stress on the dimorphism of Yarrowia lipolytica.

The Free-Living Stage Growth Conditions of the Endophytic Fungus May Regulate Its Potential as Plant Growth Promoting Microbe.

(former ) is a non-obligate endophytic fungus and generally a plant growth and defence promoter with high potential to be used in agriculture. However, may switch from biotrophy to saprotrophy losing its plant growth promoting traits. Our aim was to understand if the free-living stage growth conditions (namely C availability) regulate 's phenotype, and its potential as plant-growth-promoting-microbe (PGPM).

Inoculation with the endophytic bacterium Herbaspirillum seropedicae promotes growth, nutrient uptake and photosynthetic efficiency in rice.

Higher vacuolar proton pump activity may increase plant energy and nutrient use efficiency and provide the nexus between plant inoculation with Herbaspirillum seropedicae and growth promotion. Global change and growing human population are exhausting arable land and resources, including water and fertilizers. We present inoculation with the endophytic plant-growth promoting bacterium (PGPB) Herbaspirillum seropedicae as a strategy for promoting growth, nutrient uptake and photosynthetic efficiency in rice (Oryza sativa L.

Inoculation With Is More Efficient in Wild-Type Rice Than in Transgenic Rice Over-Expressing the Vacuolar H-PPase.

Achieving food security in a context of environmental sustainability is one of the main challenges of the XXI century. Two competing strategies to achieve this goal are the use of genetically modified plants and the use of plant growth promoting microorganisms (PGPMs). However, few studies assess the response of genetically modified plants to PGPMs.

Peptides in Combinatorial Treatment with Fluconazole: Antimicrobial Activity against Phytopathogenic Fungus.

The objective of the present study was to evaluate the antimicrobial activity of the -LTP2 and -GRP peptides isolated from seeds and their possible synergistic activity with the azole drug fluconazole and characterize their mechanisms of action on cells of pathogenic fungi. -LTP2 and -GRP alone or in combination with 20 g/mL of fluconazole were evaluated for their antimicrobial activity on the fungus , and the effects of these peptides on the permeability of membranes and the induction of oxidative stress were determined. Our results show that these peptides at a concentration of 400 g/mL combined with 20 g/mL of fluconazole were able to inhibit the growth of the tested fungi, promote changes in their growth pattern, permeabilize the membrane, and induce reactive oxygen species (ROS).

Embryogenic Competence Acquisition in Sugar Cane Callus Is Associated with Differential H-Pump Abundance and Activity.

Somatic embryogenesis is an important biological process in several plant species, including sugar cane. Proteomics approaches have shown that H pumps are differentially regulated during somatic embryogenesis; however, the relationship between H flux and embryogenic competence is still unclear. This work aimed to elucidate the association between extracellular H flux and somatic embryo maturation in sugar cane.

Programmed cell death in yeast by thionin-like peptide from fruits involving activation of caspases and extracellular H flux.

Thi is a thionin-like peptide isolated from fruits of , which has strong antimicrobial activity against bacteria, yeasts and filamentous fungi, and induced reactive oxygen species (ROS) in fungi. ROS are molecules that appear in the early stages of programmed cell death or apoptosis in fungi. Due to this fact, in this work we analyzed some events that may be related to process of apoptosis on yeast induced by Thi.

Spermine modulates fungal morphogenesis and activates plasma membrane H-ATPase during yeast to hyphae transition.

Polyamines play a regulatory role in eukaryotic cell growth and morphogenesis. Despite many molecular advances, the underlying mechanism of action remains unclear. Here, we investigate a mechanism by which spermine affects the morphogenesis of a dimorphic fungal model of emerging relevance in plant interactions, , through the recruitment of a phytohormone-like pathway involving activation of the plasma membrane P-type H-ATPase.

Alleviation of iron toxicity in Schinus terebinthifolius Raddi (Anacardiaceae) by humic substances.

One of the industrial pillars of Espírito Santo state, South East of Brazil, is iron-mining products processing. This activity brings to a high level of coastal pollution due to deposition of iron particulate on fragile ecosystems as mangroves and restinga. Schinus therebinthifolius (aroeira) is a widespread restinga species.

Crop management as a driving force of plant growth promoting rhizobacteria physiology.

Crop management systems influence plant productivity and nutrient use efficiency, as well as plant growth-promoting rhizobacteria (PGPR), which are known to influence the growth of plants via phytohormone production, phosphate solubilization, nitrogen (N) fixation and antimicrobial activity. The objective of this study was to compare the influence of two crop management system on microbial PGPR features. PGPR isolated from the rhizospheres of Carica papaya L.

Biochemical and ecophysiological responses to manganese stress by ectomycorrhizal fungus Pisolithus tinctorius and in association with Eucalyptus grandis.

At relatively low concentrations, the element manganese (Mn) is essential for plant metabolism, especially for photosynthesis and as an enzyme antioxidant cofactor. However, industrial and agricultural activities have greatly increased Mn concentrations, and thereby contamination, in soils. We tested whether and how growth of Pisolithus tinctorius is influenced by Mn and glucose and compare the activities of oxidative stress enzymes as biochemical markers of Mn stress.

Mechanistic basis for morphological damage induced by essential oil from Brazilian pepper tree, Schinus terebinthifolia, on larvae of Stegomyia aegypti, the dengue vector.

Background: Dengue has become the subject of public health programs worldwide. The lack of a vaccine and the high environmental risk of synthetic insecticides, arouse the interest in natural products against this vector. This study aimed to determine the chemical composition of the essential oil of ripe fruits and seeds of Schinus terebinthifolia Raddi; to evaluate the essential oil effect on mortality of Stegomyia aegypti (Linnaeus, 1792) larvae; and to characterize the structural damage suffered by larvae and their association with different contents of essential oil.

The essential oil of Brazilian pepper, Schinus terebinthifolia Raddi in larval control of Stegomyia aegypti (Linnaeus, 1762).

Background: The ability of mosquitoes of the genus Aedes and its allies, such as Stegomyia, to transmit diseases such as dengue and yellow fever, makes them important in public health. This study aims to evaluate the use of the essential oil of Brazilian pepper in biological control of by assessing and quantifying the larvicidal effect against S. aegypti, the only available access to dengue control, and test its risk of genotoxicity with Salmonella typhimurium as an indicator of safety for its environmental use.

Plant-microbe symbioses: new insights into common roots.

Arbuscular mycorrhiza (AM), a type of plant-fungal endosymbiosis, and nodulation, a bacterial-plant endosymbiosis, are the most ubiquitous symbioses on earth. Recent findings have established part of a shared genetic basis underlying these interactions. Here, we approach root endosymbioses through the lens of the homology and modularity concepts aiming at further clarifying the proximate and ultimate causes for the establishment of these biological systems.

pH signature for the responses of arbuscular mycorrhizal fungi to external stimuli.

Environmental and developmental signals can elicit differential activation of membrane proton (H(+)) fluxes as one of the primary responses of plant and fungal cells. In recent work,1 we could determine that during the presymbiotic growth of arbuscular mycorrhizal (AM) fungi specific domains of H(+) flux are activated by clover root factors, namely host root exudates or whole root system. Consequently, activation on hyphal growth and branching were observed and the role of plasma membrane H(+)-ATPase was investigated.

A pH signaling mechanism involved in the spatial distribution of calcium and anion fluxes in ectomycorrhizal roots.

Mycorrhization is a typical example of a host-pathogen symbiotic interaction where the pathogen cell biology and the host immune response coevolved several functional links. Here, the role played by ion fluxes across the root concerning nutrient uptake, osmoregulation, growth and signaling events is addressed. An ion-selective vibrating probe system was used to determine the net fluxes of protons (H(+)), calcium (Ca(2+)) and anions (A(-)) along nonmycorrhizal and ectomycorrhizal (ECM) roots of Eucalyptus globulus colonized by Pisolithus sp.

Arbuscular mycorrhizal fungi induce differential activation of the plasma membrane and vacuolar H+ pumps in maize roots.

Roots undergo multiple changes as a consequence of arbuscular mycorrhizal (AM) interactions. One of the major alterations expected is the induction of membrane transport systems, including proton pumps. In this work, we investigated the changes in the activities of vacuolar and plasma membrane (PM) H(+) pumps from maize roots (Zea mays L.

Proton (H+) flux signature for the presymbiotic development of the arbuscular mycorrhizal fungi.

Ion dynamics are important for cell nutrition and growth in fungi and plants. Here, the focus is on the relationship between the hyphal H(+) fluxes and the control of presymbiotic growth and host recognition by arbuscular mycorrhizal (AM) fungi. Fluxes of H(+) around azygopores and along lateral hyphae of Gigaspora margarita during presymbiotic growth, and their regulation by phosphate (P) and sucrose (Suc), were analyzed with an H(+)-specific vibrating probe.