Decolorization and biodegradation of reactive blue 220 textile dye by Lentinus crinitus extracellular extract.

Studies were carried on the decolorization of the textile dye reactive blue 220 (RB220) by a novel isolate of Lentinus crinitus fungi. The optimal conditions for the production of destaining activity were obtained in media containing intermediate concentrations of ammonium oxalate and glucose (10 g L(-1)) as nitrogen and carbon sources, respectively, at 28 degrees C and pH 5.5. Maximum decolorization efficiency against RB220 achieved in this study was around 95%. Ultra-violet and visible (UV-vis) spectrophotometric analyses, before and after decolorization, suggest that decolorization was due to biodegradation. This effect was associated with a putative low molecular weight laccase (41 kDa) displaying good tolerance to a wide range of pH values, salt concentrations and temperatures, suggesting a potential role for this organism in the remediation of real dye containing effluents.

Morphological and cytochemical characterization of spores and gills of Lepista sordida (Fungi: Basidiomycota) / Caracterização morfológica e citoquímica dos esporos e lamelas de Lepista sordida (Fungi: Basidiomycota)

Some ultrastructural and cytochemical aspects of Lepista sordida are described. Basidiospores with verruculose and irregular ornamentations were observed through scanning electron microscopy. Confocal microscopy indicated that most of them exhibited a single large lipid body, no acidic vesicles and nucleus localized in the cell periphery.

Este trabalho descreve aspectos ultraestruturais e citoquímicos de Lepista sordida. Basidiósporos recobertos com ornamentações verruculosas e irregulares foram observados através de microscopia eletrônica de varredura. Através de microscopia confocal verificou-se que a maioria apresentava um grande corpo lipídico, ausência de vesículas ácidas e núcleo localizado na periferia.

Morphological and cytochemical characterization of spores and gills of Lepista sordida (Fungi: Basidiomycota).

Some ultrastructural and cytochemical aspects of Lepista sordida are described. Basidiospores with verruculose and irregular ornamentations were observed through scanning electron microscopy. Confocal microscopy indicated that most of them exhibited a single large lipid body, no acidic vesicles and nucleus localized in the cell periphery.

Morphology and lipid body and vacuole dynamics during secondary conidia formation in Colletotrichum acutatum: laser scanning confocal analysis.

Colletotrichum acutatum may develop one or more secondary conidia after conidial germination and before mycelial growth. Secondary conidia formation and germination were influenced by conidia concentration. Concentrations greater than 1x105 conidia/mL were associated with germination decrease and with secondary conidia emergence. Secondary conidia can form either alone or simultaneously with germ tubes and appressoria. Confocal analysis showed numerous lipid bodies stored inside ungerminated conidia, which diminished during germ tube and appressoria formation, with or without secondary conidia formation. They were also reduced during secondary conidia formation alone. While there was a decrease inside germinated conidia, lipid bodies appeared inside secondary conidia since the initial stages. Intense vacuolization inside primary germinated conidia occurred at the same time as the decrease in lipid bodies, which were internalized and digested by vacuoles. During these events, small acidic vesicles inside secondary conidia were formed. Considering that the conidia were maintained in distilled water, with no exogenous nutrients, it is clear that ungerminated conidia contain enough stored lipids to form germ tubes, appressoria, and the additional secondary conidia replete with lipid reserves. These results suggested a very complex and well-balanced regulation that makes possible the catabolic and anabolic pathways of these lipid bodies.

Phagocytosis, endosomal/lysosomal system and other cellularaspects of macrophage activation by Canova medication.

Canova is a homeopathic medication with immunomodulatory properties, recommended for diseases where the immune system is depressed. Our research aims to study the activation of mice peritoneal macrophages when submitted to in vivo and in vitro Canova treatment. Morphological parameters and acid phosphatase activity were analyzed using light and transmission electron microscopy. Differential interference contrast microscopy, including serial time acquisition in living cells, was also performed. The results demonstrated a greater spreading ability in Canova treated macrophages, a higher phagocytic activity of non-infective microorganisms (Saccharomyces cerevisiae and Tripanosoma cruzi epimastigotes) and a tendency to lower the phagocytic activity of the infective microorganisms T. cruzi trypomastigotes and Leishmania amazonensis, when compared with control cells. Acid phosphatase activity was analyzed and showed that Canova treatment stimulates an increase of the endosomal/lysosomal system. Treated macrophages that do or do not interact with yeast present a higher number of acid phosphatase marked vesicles compared to control cells. In contrast, the activity of tartrate resistant acid phosphatase (TRAP), is lower in Canova treated macrophages. The net results demonstrate that Canova medication is an effective stimulator of macrophage activity.

Vacuolar system of ungerminated Colletotrichum graminicola conidia: convergence of autophagic and endocytic pathways.

Vacuoles of ungerminated Colletotrichum graminicola conidia engulf cytoplasmic structures by a process analogous to microautophagy, demonstrated by using a vacuolar membrane acid phosphatase marker. Fusion of vesicles with vacuoles, without deposition of the acid phosphatase reaction product has been observed, suggesting other pathways of material delivery to vacuoles than microautophagy. Plasma membrane invaginations, multivesicular bodies and retention of neutral red into small vesicles, which were internalized by the vacuole, were verified. These results provided evidence for endocytosis and an active endosomal system. Together, our findings with C. graminicola demonstrated that vacuoles are very dynamic compartments, playing roles in autophagy and endocytic processes.

Acid phosphatase activity in ungerminated conidia from Colletotrichum graminicola as determined by spectrophotometric and cytochemical methods

The acid phosphatase in ungerminated conidia from Colletotrichum graminicola, a corn pathogen, was investigated using spectrophotometric and cytochemical methods. Acid phosphatase activity was studied in a homogenate obtained by fragmentation of ungerminated conidia. With p-nitrophenylphosphate as substrate, the apparent Vmax and Km were 1.000 nmol p-nitrophenol/mg of protein/min and 0.631 mM, respectively. The pH and temperature optima were 5.5 and 60 graus Celsius, respectively. A cytochemical ultrastructural assay showed deposition of the reaction product inside vacuoles but not extracellularly on the cell surface. The permeabilization of conidia with Triton X-100 increased acid phosphatase activity eight fold. Compared to other procedures, our method was fast, easy to perform and gave consistent results.