Transcriptional and Post-Translational Roles of Calcineurin in Cationic Stress and Glycerol Biosynthesis in .

Stress management is an adaptive advantage for survival in adverse environments. Pathogens face this challenge during host colonization, requiring an appropriate stress response to establish infection. The fungal pathogen undergoes thermal, oxidative, and osmotic stresses in the environment and animal host.

ATP sulfurylase atypical leucine zipper interacts with Cys3 and calcineurin A in the regulation of sulfur amino acid biosynthesis in Cryptococcus neoformans.

Fungal pathogens are a major cause of death, especially among immunocompromised patients. Therapies against invasive fungal infections are restricted to a few antifungals; therefore, novel therapies are necessary. Nutritional signaling and regulation are important for pathogen establishment in the host.

Coumaric acid analogues inhibit growth and melanin biosynthesis in Cryptococcus neoformans and potentialize amphotericin B antifungal activity.

Fungal infections are on the rise, since the imunocompromised population is increasing due to AIDS/HIV, organ transplant and chemotherapy. Many environmental and pathogenic fungi are able to accomplish melanin biosynthesis as a virulence factor to promote host invasion. Melanized cells are more resistant to radiation, oxidative and osmotic stresses; also melanin confers an advantage in vivo, since melanized cells are more resistant to phagocytic engulfment and oxidative stress caused by the host defense cells and by some antifungal drugs, such as fluconazole (FCZ) and amphotericin B (AmB).

Biological functions of the autophagy-related proteins Atg4 and Atg8 in Cryptococcus neoformans.

Autophagy is a mechanism responsible for intracellular degradation and recycling of macromolecules and organelles, essential for cell survival in adverse conditions. More than 40 autophagy-related (ATG) genes have been identified and characterized in fungi, among them ATG4 and ATG8. ATG4 encodes a cysteine protease (Atg4) that plays an important role in autophagy by initially processing Atg8 at its C-terminus region.

The Glycerol Phosphatase Gpp2: A Link to Osmotic Stress, Sulfur Assimilation and Virulence in .

is an opportunist fungal pathogen that causes meningoencephalitis in immunocompromised patients. During infection, this basidiomycete yeast has to adapt to several adverse conditions, especially nutrient availability. The interruption on various amino acid biosynthetic pathways and on amino acid uptake causes reduced viability, inability to cope with various stresses, failure in virulence factors expression and avirulence in animal model of infection.

The regulation of the sulfur amino acid biosynthetic pathway in Cryptococcus neoformans: the relationship of Cys3, Calcineurin, and Gpp2 phosphatases.

Cryptococcosis is a fungal disease caused by C. neoformans. To adapt and survive in diverse ecological niches, including the animal host, this opportunistic pathogen relies on its ability to uptake nutrients, such as carbon, nitrogen, iron, phosphate, sulfur, and amino acids.

Amino acid permeases in Cryptococcus neoformans are required for high temperature growth and virulence; and are regulated by Ras signaling.

Cryptococcosis is an Invasive Fungal Infection (IFI) caused by Cryptococcus neoformans, mainly in immunocompromised patients. Therapeutic failure due to pathogen drug resistance, treatment inconstancy and few antifungal options is a problem. The study of amino acid biosynthesis and uptake represents an opportunity to explore possible development of novel antifungals.

AKT/protein kinase B associates with β-actin in the nucleus of melanoma cells.

The serine-threonine kinase AKT/PKB is a critical regulator of various essential cellular processes, and dysregulation of AKT has been implicated in many diseases, including cancer. Despite AKT action is known to function mainly in the cytoplasm, AKT has been reported to translocate to the nucleus. However, very little is known about the mechanism required for the nuclear import of AKT as well as its function in this cellular compartment.

Chemical Composition and In Vitro Cytotoxic and Antimicrobial Activities of the Essential Oil from Leaves of Zanthoxylum monogynum St. Hill (Rutaceae).

: The species belongs to the family Rutaceae and is found in Southeast, Midwest, and Northeast Brazil. For this genus several biological activities have been described. : The essential oil (EO) was obtained from the leaves of by hydro-distillation and was analyzed by gas chromatograph and gas chromatograph/mass spectrometry (GC and GC/MS).

Cytotoxic and Antimicrobial Constituents from the Essential Oil of Lippia alba (Verbenaceae).

(Verbenaceae) is a plant widely used in folk medicine to treat various diseases. The present work deals with the chemical composition of the crude essential oil extracted from leaves of and evaluation of its antimicrobial and cytotoxic activities. Leaves of were extracted by hydrodistillation and analyzed by gas chromatography/mass spectrometry (GC/MS) as well as by nuclear magnetic resonance (NMR) spectroscopy.

The role of Aspartyl aminopeptidase (Ape4) in Cryptococcus neoformans virulence and authophagy.

In order to survive and cause disease, microbial pathogens must be able to proliferate at the temperature of their infected host. We identified novel microbial features associated with thermotolerance in the opportunistic fungal pathogen Cryptococcus neoformans using a random insertional mutagenesis strategy, screening for mutants with defective growth at 37°C. Among several thermosensitive mutants, we identified one bearing a disruption in a gene predicted to encode the Ape4 aspartyl aminopeptidase protein.

Amino Acid Permeases and Virulence in Cryptococcus neoformans.

Fungal opportunistic pathogens colonize various environments, from plants and wood to human and animal tissue. Regarding human pathogens, one great challenge during contrasting niche occupation is the adaptation to different conditions, such as temperature, osmolarity, salinity, pressure, oxidative stress and nutritional availability, which may constitute sources of stress that need to be tolerated and overcome. As an opportunistic pathogen, C.

The Role of Amino Acid Permeases and Tryptophan Biosynthesis in Cryptococcus neoformans Survival.

Metabolic diversity is an important factor during microbial adaptation to different environments. Among metabolic processes, amino acid biosynthesis has been demonstrated to be relevant for survival for many microbial pathogens, whereas the association between pathogenesis and amino acid uptake and recycling are less well-established. Cryptococcus neoformans is an opportunistic fungal pathogen with many habitats.

Assessing the Chemical Composition and Antimicrobial Activity of Essential Oils from Brazilian Plants-Eremanthus erythropappus (Asteraceae), Plectrantuns barbatus, and P. amboinicus (Lamiaceae).

The chemical composition and antimicrobial activity of essential oils obtained from three Brazilian plant species-leaves and branches of Eremanthus erythropappus (Asteraceae), leaves of Plectranthus barbatus, and leaves of P. amboinicus (Lamiaceae)-were determined. Analysis by GC/MS and determination of Kovats indexes both indicated δ-elemene (leaves-42.

A simple and effective method to synthesize fluorescent nanoparticles using tryptophan and light and their lethal effect against bacteria.

A simple, environmentally friendly and cost-effective method was used to synthesize silver nanoparticles using tryptophan and light. To prepare the nanoparticles, the following components were used: deionized water, silver nitrate, light and tryptophan. The effects of the tryptophan concentration and light exposure time on the formation of tryptophan silver nanoparticles (Tnnps) were studied.

The role of the de novo pyrimidine biosynthetic pathway in Cryptococcus neoformans high temperature growth and virulence.

Fungal infections are often difficult to treat due to the inherent similarities between fungal and animal cells and the resulting host toxicity from many antifungal compounds. Cryptococcus neoformans is an opportunistic fungal pathogen of humans that causes life-threatening disease, primarily in immunocompromised patients. Since antifungal therapy for this microorganism is limited, many investigators have explored novel drug targets aim at virulence factors, such as the ability to grow at mammalian physiological temperature (37°C).

The seasonal variation of the chemical composition of essential oils from Porcelia macrocarpa R.E. Fries (Annonaceae) and their antimicrobial activity.

This study investigates the impact of seasonal variation on the chemical composition of essential oils from the leaves of Porcelia macrocarpa (Annonaceae) obtained over the course of one year (January-December 2011) and the chemical composition of the essential oils obtained from the ripe fruits of the same plant. Furthermore, the essential oils of the leaves were investigated with respect to their antimicrobial activity. The essential oils of the leaves contain a mixture of monoterpenes, one diterpene and several sesquiterpenes.

Metagenomic analysis of a tropical composting operation at the são paulo zoo park reveals diversity of biomass degradation functions and organisms.

Composting operations are a rich source for prospection of biomass degradation enzymes. We have analyzed the microbiomes of two composting samples collected in a facility inside the São Paulo Zoo Park, in Brazil. All organic waste produced in the park is processed in this facility, at a rate of four tons/day.

Chemical and biological evaluation of essential oils from two species of Myrtaceae - Eugenia uniflora L. and Plinia trunciflora (O. Berg) Kausel.

The chemical composition and antimicrobial activity of essential oils obtained from leaves of two Myrtaceae species-Eugenia uniflora L. and Plinia trunciflora (O. Berg) Kausel-were determined.

Internally quenched fluorescent peptide libraries with randomized sequences designed to detect endopeptidases.

Identification of synthetic peptide substrates for novel peptidases is an essential step for their study. With this purpose we synthesized fluorescence resonance energy transfer (FRET) peptide libraries Abz (or MCA)-GXXXXXQ-EDDnp and Abz (or MCA)-GXXZXXQ-EDDnp, where X consists of an equimolar mixture of all amino acids, the Z position is fixed with one of the proteinogenic amino acids (cysteine was excluded), Abz (ortho-aminobenzoic acid) or MCA ([7-amino-4-methyl]coumarin) is the fluorescence donor and Q-EDDnp (glutamine-[N-(2,4-dinitrophenyl)-ethylenediamine]) is the fluorescence acceptor. The peptide libraries MCA-GXXX↓XXQ-EDDnp and MCA-GXXZ↓XXQ-EDDnp were cleaved as indicated (↓) by trypsin, chymotrypsin, cathepsin L, pepsin A, and Eqolisin as confirmed by Edman degradation of the products derived from the digestion of these libraries.

Amylolytic microorganism from são paulo zoo composting: isolation, identification, and amylase production.

Composting is a way of transforming the organic waste into fertilizer, minimizing the use of inorganic compounds that may contaminate the environment. This transformation is the result of the microorganism action, converting complex carbon sources into energy. Enzymes that are exported by the microorganisms to the surrounding environment mediate this process.