Molecular mechanism for regulating APOBEC3G DNA editing function by the non-catalytic domain.

APOBEC3G (A3G) belongs to the AID/APOBEC cytidine deaminase family and is essential for antiviral immunity. It contains two zinc-coordinated cytidine-deaminase (CD) domains. The N-terminal CD1 domain is non-catalytic but has a strong affinity for nucleic acids, whereas the C-terminal CD2 domain catalyzes C-to-U editing in single-stranded DNA. The interplay between the two domains in DNA binding and editing is not fully understood. Here, our studies on rhesus macaque A3G (rA3G) show that the DNA editing function in linear and hairpin loop DNA is greatly enhanced by AA or GA dinucleotide motifs present downstream (in the 3'-direction) but not upstream (in the 5'-direction) of the target-C editing sites. The effective distance between AA/GA and the target-C sites depends on the local DNA secondary structure. We present two co-crystal structures of rA3G bound to ssDNA containing AA and GA, revealing the contribution of the non-catalytic CD1 domain in capturing AA/GA DNA and explaining our biochemical observations. Our structural and biochemical findings elucidate the molecular mechanism underlying the cooperative function between the non-catalytic and the catalytic domains of A3G, which is critical for its antiviral role and its contribution to genome mutations in cancer.

Oral Administration of Lactobacillus Inhibits the Permeability of Blood-Brain and Gut Barriers in a Parkinsonism Model.

It has recently been shown that the administration of probiotics can modulate the microbiota-gut-brain axis and may have favorable effects in models of Parkinson's disease. In this study, we used a hemiparkinsonism model induced by the neurotoxin 6-OHDA to evaluate the efficacy of the administration of a four-week administration of a mixture containing the microorganisms Lactobacillus fermentum LH01, Lactobacillus reuteri LH03, and Lactobacillus plantarum LH05. The hemiparkinsonism model induced an increase in rotations in the apomorphine test, along with a decrease in the latency time to fall in the rotarod test on days 14 and 21 after surgery, respectively. The administration of probiotics was sufficient to improve this condition. The model also showed a decrease in tyrosine hydroxylase immunoreactivity in the striatum and the number of labeled cells in the substantia nigra, both of which were counteracted by the administration of probiotics. The permeability of the blood-brain barrier was increased in the model, but this effect was reversed by the probiotics for both brain regions. The gut barrier was permeated with the model, and this effect was reversed and dropped to lower levels than the control group after the administration of probiotics. Finally, lipid peroxidation showed a pattern of differences similar to that of permeabilities. The inhibition of the permeability of the blood-brain and gut barriers mediated by the administration of probiotics will likely provide protection by downregulating oxidative stress, thus affecting the rotarod test performance.

Effects of maternal toxic substance consumption during breastfeeding on lactic acid bacteria abundance and nutritional content.

Breast milk is widely recognized as the primary source of nourishment for newborns, making it an unparalleled and indispensable provider of essential nutrients, microbiological components, immunological factors, and energy content. To investigate this further, a cohort comprising 254 breastfeeding women participated in interviews, and milk samples were aseptically collected for subsequent analysis involving bromatological, microbiological, and clinical analysis. The investigation focused on the identification of specific microorganisms in breast milk and their susceptibility to the exposure of toxic substances and controlled medications. Notably, this study places particular emphasis on the significant decline in lactic acid bacteria observed in breast milk when influenced by substances such as cocaine, cannabis, crystal, and morphine. These detrimental agents have been found to adversely affect the growth of microorganisms within breast milk. On the contrary, the outcomes of this study indicate that the utilization of toxic substances does not exert a noteworthy impact on the nutritional quality of breast milk.

Improvement and Validation of a Genomic DNA Extraction Method for Human Breastmilk.

The human milk microbiota (HMM) of healthy women can vary substantially, as demonstrated by recent advances in DNA sequencing technology. However, the method used to extract genomic DNA (gDNA) from these samples may impact the observed variations and potentially bias the microbiological reconstruction. Therefore, it is important to use a DNA extraction method that is able to effectively isolate gDNA from a diverse range of microorganisms. In this study, we improved and compared a DNA extraction method for gDNA isolation from human milk (HM) samples to commercial and standard protocols. We evaluated the extracted gDNA using spectrophotometric measurements, gel electrophoresis, and PCR amplifications to assess its quantity, quality, and amplifiability. Additionally, we tested the improved method's ability to isolate amplifiable gDNA from fungi, Gram-positive and Gram-negative bacteria to validate its potential for reconstructing microbiological profiles. The improved DNA extraction method resulted in a higher quality and quantity of the extracted gDNA compared to the commercial and standard protocols and allowed for polymerase chain reaction (PCR) amplification of the V3-V4 regions of the 16S ribosomal gene in all the samples and the ITS-1 region of the fungal 18S ribosomal gene in 95% of the samples. These results suggest that the improved DNA extraction method demonstrates better performance for gDNA extraction from complex samples such as HM.

Structural basis of sequence-specific RNA recognition by the antiviral factor APOBEC3G.

An essential step in restricting HIV infectivity by the antiviral factor APOBEC3G is its incorporation into progeny virions via binding to HIV RNA. However, the mechanism of APOBEC3G capturing viral RNA is unknown. Here, we report crystal structures of a primate APOBEC3G bound to different types of RNAs, revealing that APOBEC3G specifically recognizes unpaired 5'-AA-3' dinucleotides, and to a lesser extent, 5'-GA-3' dinucleotides. APOBEC3G binds to the common 3'A in the AA/GA motifs using an aromatic/hydrophobic pocket in the non-catalytic domain. It binds to the 5'A or 5'G in the AA/GA motifs using an aromatic/hydrophobic groove conformed between the non-catalytic and catalytic domains. APOBEC3G RNA binding property is distinct from that of the HIV nucleocapsid protein recognizing unpaired guanosines. Our findings suggest that the sequence-specific RNA recognition is critical for APOBEC3G virion packaging and restricting HIV infectivity.

Human lactoferrin from breast milk: characterization by HPLC and its in vitro antibiofilm performance.

Preterm infants are at high risk of infection due to opportunistic bacteria as Pseudomonas aeruginosa, causing infections among infants in neonatal intensive care units. Human lactoferrin (hLf) is a multifunctional protein and one of the most abundant in breast milk, and plays an important role in prevention of different infections in neonates. This work offers a strategy to obtain a lyophilisate of purified lactoferrin from breast milk. In addition, a reliable HPLC method for quantification of lactoferrin with a linear quantification range of 0.040-0.140 mg/mL with selectivity, accuracy and repeatability, is described. Lyophilized hLf was obtained by purification through a heparin affinity column followed by ultrafiltration with a 30 kDa membrane. The final solution was lyophilized and the product was analyzed using HPLC method, recovering about 70% of initial lactoferrin in the sample. This molecule was elucidated through FTIR spectroscopy and SDS-PAGE electrophoresis. In addition, the capacity against biofilm formation of P. aeruginosa was demonstrated with 75% of inhibition at 6 mg/mL. These results suggest that lyophilized hLf can be obtained by purification of breast milk and that it can provide antibiofilm activity against P. aeruginosa.

Estimation of metabolic fluxes distribution in Saccharomyces cerevisiae during the production of volatile compounds of Tequila.

A stoichiometric model for Saccharomyces cerevisiae is reconstructed to analyze the continuous fermentation process of agave juice in Tequila production. The metabolic model contains 94 metabolites and 117 biochemical reactions. From the above set of reactions, 93 of them are linked to internal biochemical reactions and 24 are related to transport fluxes between the medium and the cell. The central metabolism of S. cerevisiae includes the synthesis for 20 amino-acids, carbohydrates, lipids, DNA and RNA. Using flux balance analysis (FBA), different physiological states of S. cerevisiae are shown during the fermentative process; these states are compared with experimental data under different dilution rates (0.04-0.12 h$ ^{-1} $). Moreover, the model performs anabolic and catabolic biochemical reactions for the production of higher alcohols. The importance of the Saccharomyces cerevisiae genomic model in the area of alcoholic beverage fermentation is due to the fact that it allows to estimate the metabolic fluxes during the beverage fermentation process and a physiology state of the microorganism.

In vivo assessment and characterization of lactic acid bacteria with probiotic profile isolated from human milk powder.

INTRODUCTION: Introduction: breast milk (MH) contains nutrients and bioactive compounds for child development, including probiotic bacteria, which contribute to intestinal maturation. This benefit accompanies the individual until adulthood. There are new methods such as spray drying that give this compound a good conservation without loss of microbiota. Objective: the aim of this study was to analyze the viability of lactic acid bacteria isolated from human milk with probiotic potential after the spray drying process, as well as to evaluate the possible adhesion in the colon of mice of the Balb/C strain after feeding them powdered human milk and a commercial formula milk. Method: we isolated and identified the presence of lactic acid bacteria with possible probiotic potential in powdered human milk using the MALDI-TOF MS technique. Powdered human milk and a commercial formula milk were fed to mice of the Bald/C strain for 14 weeks. Glucose level and weight were measured in the mice. The feces were collected to verify the presence of lactic bacteria. The mice were sacrificed and their intestines were weighed, isolating the lactic acid bacteria both from the intestines and from the feces. The strains isolated from mice fed human milk were evaluated for their probiotic potential, analyzing their ability to inhibit pathogens, resistance to pH, temperature, adhesion, and hydrophobicity. Results: the presence of Lactobacillus fermentum LH01, Lactobacillus rhamnosus LH02, Lactobacullis reuteri LH03, and Lactobacillus plantarum LH05 in powdered human milk was identified. All strains showed a possible probiotic profile due to the ability of bacteria to resist low pH, bile salts, and exposure to gastric enzymes, as well as their hydrophobicity and self-aggregation capacity, and their failure to show hemagglutination or hemolysis activity in a culture medium rich in erythrocytes. We observed that the consumption of powdered human milk prevented weight gain and constipation in mice. Conclusions: after spray drying, strains with possible probiotic potential may be preserved in human milk. The consumption of powdered human milk with probiotic bacteria prevents constipation and weight gain in mice, when compared to those fed a commercial formula milk.

INTRODUCCIÓN: Introducción: la leche materna (HM) contiene los nutrientes y compuestos bioactivos necesarios para el desarrollo infantil, incluidas bacterias probióticas, que contribuyen a la maduración intestinal. Objetivo: el objetivo de este estudio fue analizar la viabilidad de las bacterias acidolácticas aisladas de la leche humana con potencial probiótico, después del proceso de secado, así como evaluar su posible adhesión en el colón de ratones (BAlb/C) alimentados con leche humana en polvo y leche de una fórmula comercial. Método: se aislaron e identificaron mediante la técnica de Maldi-Tof-MS las bacterias acidolácticas con posible potencial probiótico en la leche humana en polvo. Se alimentó con leche humana en polvo y leche de una fórmula comercial a ratones de la cepa Bald/C durante 14 semanas. Se midieron el nivel de glucosa y el peso. Las heces se recolectaron para verificar la presencia de bacterias lácticas. Los ratones se sacrificaron y se pesaron los intestinos, aislando las bacterias lácticas tanto de los intestinos como de las heces. En las cepas aisladas de la leche humana se evaluó el potencial probiótico analizando su capacidad para inhibir patógenos, resistir distintos pH y temperaturas, adherirse y mostrar hidrofobicidad. Resultados: se identificó la presencia de Lactobacillus fermentum LH01, Lactobacillus rhamnosus LH02, Lactobacullis reuteri LH03 y L. plantarum LH05 en la leche humana en polvo. Todas las cepas mostraron resistencia a los pH bajos, a las sales biliares y a la exposición a enzimas gástricas, así como una buena hidrofobicidad y capacidad de autoagregación. Además, no presentaron actividad de hemaglutinación o hemólisis en un medio de cultivo rico en eritrocitos. Observamos que el consumo de leche humana en polvo evita en los ratones el aumento de peso y el estreñimiento. Conclusiones: después del secado por aspersión, las cepas con posible potencial probiótico pueden conservarse en la leche materna. El consumo de leche humana en polvo con bacterias probióticas evita el estreñimiento y el aumento de peso en los ratones, en comparación con los alimentados con leche de una formula comercial.

In-vivo assessment of the protection of ß-glucans of Pleurotus ostreatus against oxidative stress caused by acrylamide intake (part II).

INTRODUCTION: Introduction: in April 2002, the National Food Authority of Sweden published a study in which the presence of a carcinogen was reported for the first time in experimental animals, and was identified as acrylamide. Various studies have shown that the ß-glucans of Pleurotus ostreatus have diverse biological properties including antioxidant and anticancer activities. Methods: ß-glucans were obtained by alkaline-acid hydrolysis from Pleurotus ostreatus, and their content was characterized by liquid chromatography. To evaluate the effect of ß-glucans on the expression of glutathione, Balb/c mice were used, and 4 test groups were established. All groups were fed as usual, groups treated with acrylamide were administered the compound intragastrically at a concentration of 50 g/mL, and ß-glucan treatment was given at a concentration of 50 g/mL. Results: no mortality was observed after exposure to the tested dose of acrylamide; only signs of peripheral neuropathy such as hyperactivity and tremors were observed after five days of experimentation, and were maintained over 30 days after the experiment. On the other hand, an increase in lipid peroxidation levels was observed in the livers of the acrylamide-treated mice, which were lower in the mice treated with ß-glucans. Conclusions: results show that ß-glucans may act as antioxidant agents able to protect the liver against oxidative stress as caused by the intake of acrylamide.

INTRODUCCIÓN: Introducción: en abril de 2002, la Autoridad Nacional de Alimentos de Suecia publicó un estudio en el que se informó por primera vez de la presencia de un carcinógeno en animales experimentales, identificado como acrilamida. Diversos estudios han demostrado que los ß-glucanos de Pleurotus ostreatus tienen diversas propiedades biológicas, tales como actividades antioxidantes y anticancerígenas. Métodos: los ß-glucanos se obtuvieron por hidrólisis ácido-alcalina de Pleurotus ostreatus y su contenido se caracterizó por cromatografía líquida. Para evaluar el efecto de los ß-glucanos sobre la expresión de glutatión, se usaron ratones Balb/c y se establecieron 4 grupos de prueba; todos los grupos se alimentaron normalmente, en los grupos tratados con acrilamida esta se administró intragástricamente a una concentración de 50 µg/mL, y el tratamiento con ß-glucanos se dio a una concentración de 50 µg/mL. Resultados: no se observó mortalidad después de la exposición a la dosis probada de acrilamida; solo se observaron signos de neuropatía periférica, como hiperactividad y temblores, después de cinco días de experimentación, que se mantuvieron dentro de los 30 días posteriores al experimento. Por otro lado, se observó un aumento de los niveles de peroxidación lipídica en los hígados de los ratones tratados con acrilamida, que fueron más bajos en los ratones tratados con ß-glucanos. Conclusiones: los resultados muestran que los ß-glucanos podrían actuar como agentes antioxidantes y proteger el hígado contra el estrés oxidativo causado por la ingesta de acrilamida.

In vivo assessment of the protection conferred by ß-glucans from Pleurotus ostreatus against the harmful effects of acrylamide intake (Part I).

INTRODUCTION: Introduction: acrylamide is formed in food through Maillard's reaction during thermal processing, and has been shown to be neurotoxic in humans, and a possible carcinogen. Studies have shown that ß-glucans from Pleurotus ostreatus have diverse biological properties such as antioxidant and anticancer activities. Objective: the aim of this work was to evaluate the protective effect of ß-glucans from Pleurotus ostreatus against the harmful effects of acrylamide consumption in mice. Methods: ß-glucans were obtained by alkaline-acid hydrolysis of Pleurotus ostreatus, and the content was characterized by liquid chromatography. To evaluate the effect of ß-glucans on the expression of glutathione, Balb/c mice were used, and 4 test groups were established. All groups were fed normally, and the groups treated with acrylamide were administered the compound intragastrically at a concentration of 50 g/mL; ß-glucans were administered at a concentration of 50 g/mL. Results: mice exposed to acrylamide showed a marked variation in the activity of glutathione enzymes in the liver. Significant differences (p < 0.05) were only found in the expression of glutathione transferase, which was increased almost 3 times in the group treated with ß-glucans as compared with the control group, and 1.5 times as compared with the group treated with acrylamide. Conclusions: the results show that ß-glucans could act by increasing the activity of enzymes involved in xenobiotic detoxification, thus protecting the biological system against the harmful effects caused by acrylamide intake.

INTRODUCCIÓN: Introducción: la acrilamida se forma en los alimentos a través de la reacción de Maillard durante el proceso térmico, y ha demostrado ser neurotóxica en humanos y un posible carcinógeno. Algunos estudios han demostrado que los ß-glucanos de Pleurotus ostreatus tienen diversas propiedades biológicas, como actividades antioxidantes y anticancerígenas. Objetivo: el objetivo de este trabajo fue evaluar el efecto protector de los ß-glucanos de Pleurotus ostreatus contra los efectos nocivos por consumo de acrilamida en ratones (prueba in vivo). Métodos: los ß-glucanos se obtuvieron por hidrólisis ácido-alcalina de Pleurotus ostreatus y su contenido se caracterizó por cromatografía líquida. La oxidación de los lípidos se evaluó mediante el método de TBARS, y para evaluar el efecto de los ß-glucanos en la expresión de glutatión se usaron ratones Balb/c, y se establecieron 4 grupos de prueba. Todos los grupos fueron alimentados normalmente; a lo grupos tratados con acrilamida, esta se les administró intragástricamente en una concentración de 50 µg/ml, y los ß-glucanos en una concentración de 50 µg/ml. Resultados: en el presente trabajo, los ratones expuestos a acrilamida mostraron una marcada variación en la actividad de las enzimas de glutatión determinadas en el hígado. Solo se encontraron diferencias significativas (p < 0,05) en la expresión de glutatión-transferasa, que aumentó casi 3 veces en el grupo tratado con ß-glucano en comparación con el grupo de control, y 1,5 veces con respecto al grupo tratado con acrilamida. Conclusiones: los resultados muestran que los ß-glucanos podrían actuar como agentes antioxidantes que protegen el hígado contra el estrés oxidativo causado por la ingesta de acrilamida.

Cold Plasma Treatment as an Alternative for Ochratoxin a Detoxification and Inhibition of Mycotoxigenic Fungi in Roasted Coffee.

Ochratoxin A (OTA) produced by mycotoxigenic fungi (Aspergillus and Penicillium spp.) is an extremely toxic and carcinogenic metabolite. The use of cold plasma to inhibit toxin-producing microorganisms in coffee could be an important alternative to avoid proliferation of mycotoxigenic fungi. Roasted coffee samples were artificially inoculated with A. westerdijikiae, A. steynii, A. versicolor, and A. niger, and incubated at 27 °C over 21 days for OTA production. Samples were cold plasma treated at 30 W input power and 850 V output voltage with helium at 1.5 L/min flow. OTA production in coffee was analyzed by high performance liquid chromatography coupled to a mass spectrometer (HPLC-MS). After 6 min of treatment with cold plasma, fungi were completely inhibited (4 log reduction). Cold plasma reduces 50% of OTA content after 30 min of treatment. Toxicity was estimated for extracts of artificially contaminated roasted coffee samples using the brine shrimp (Artemia salina) lethality assay. Toxicity for untreated roasted coffee was shown to be "toxic", while toxicity for cold plasma treated coffee was reduced to "slightly toxic". These results suggested that cold plasma may be considered as an alternative method for the degradation and reduction of toxin production by mycotoxigenic fungi in the processing of foods and feedstuffs.

Kinetic and spectroscopic characterization of tungsten-substituted DMSO reductase from Rhodobacter sphaeroides.

We have examined the kinetic and spectroscopic properties of a tungsten-substituted form of DMSO reductase from Rhodobacter sphaeroides, an enzyme that normally possesses molybdenum. Partial reduction with sodium dithionite yields a well-resolved W(V) EPR signal of the so-called "high-g split" type that exhibits markedly greater g-anisotropy than the corresponding Mo(V) signal of the native form of the enzyme, with the g values shifted to higher magnetic field by as much as Δgave = 0.056. Deuteration of the enzyme confirms that the coupled proton is solvent-exchangeable, allowing us to accurately simulate the tungsten hyperfine coupling. Global curve-fitting analysis of UV/vis absorption spectra observed in the course of the reaction of the tungsten-substituted enzyme with sodium dithionite affords a well-defined absorption spectrum for the W(V) species. Surprisingly, the absorption spectrum for this species exhibits significantly larger molar extinction coefficients than either the reduced or the oxidized spectrum. This spectrum, in conjunction with those for fully oxidized W(VI) and fully reduced W(IV) enzyme, has been used to deconvolute the absorption spectra seen in the course of turnover, in the which enzyme is reacted with sodium dithionite and DMSO, demonstrating that the W(V) is an authentic catalytic intermediate that accumulates to approximately 50% of the total enzyme in the steady state.

[Impact of pasteurization/freeze-drying on available immunoglobulin content of the mature human milk. Use in human milk banking of hospitals]. / Impacto de la pasteurización/liofilización en el contenido disponible de inmunoglobulinas en leche humana madura. Estudio de aplicación en bancos de leche humana en hospitales.

INTRODUCTION: This study analyzes the effect on the content of immunoglobulins and C3 complement of freeze drying after pasteurization by three different methods in mature human milk (MHM). OBJECTIVE: Freeze drying is proposed as a complementary method for the maintenance of MHM therapeutic properties with greater validity. METHODS: This was a descriptive study in which MHM samples were obtained. Next, aliquots of the samples obtained were pasteurized by three methods: 62.5 centigrades degrees/30 minutes, 72 centigrades degrees/15 minutes, 85 centigrades degrees/5 minutes, followed by a rapid cooling at 5 ºC. Then, 30 ml volumes of pasteurized sample were freeze-dried over a period of 36 hours. Total protein determination was performed by the Lowry method. The concentrations of immunoglobulins A, G and M, and complement C3, were determined by conventional nephelometric technique following the manufacturer's instructions. Statistical significance was defined as p < 0.05. RESULTS: The method of pasteurization of MHM with increased protein and immunoglobulin retention was at 62.5 centigrades degrees, however, pasteurization at 72 centigrades degrees before freeze-drying showed better retention of immunoglobulins. CONCLUSIONS: Our results suggest that the freeze-drying of pasteurized MHM is a suitable method for the conservation in human milk banks. Both the nutritional composition and the extension of its validity and the application of the two processes together provide the advantage of maintaining the therapeutic properties of human milk to improve the health of the newborn in a vulnerable, impaired or immunosuppressed state.

INTRODUCCIÓN: este estudio analiza el efecto sobre el contenido de inmunoglobulinas y complemento C3 de la liofilización posterior a la pasteurización por tres métodos diferentes en leche humana madura (LHM). OBJETIVO: la liofilización es propuesta como método complementario para el mantenimiento de las propiedades terapéuticas de la LHM con mayor vigencia. MÉTODOS: estudio descriptivo en el que se obtuvieron muestras de LHM. Alícuotas de las muestras obtenidas se pasteurizaron por tres métodos: 62,5 grados centígrados/30 minutos, 72 grados centígrados/15 minutos 85 grados centígrados/5 minutos, seguido de un enfriamiento rápido a 5 grados centígrados. Después, volúmenes de 30 ml de muestra pasteurizada fueron liofilizados durante un periodo de 36 horas. La determinación de proteínas totales fue realizada por el método Lowry. Las concentraciones de inmunoglobulinas A, G y M y el complemento C3 fueron determinadas por nefelometría convencional, siguiendo las instrucciones del fabricante. La significancia estadística se definió como p < 0,05. RESULTADOS: el método de pasteurización de LHM con mayor retención de proteína e inmunoglobulinas fue a la temperatura de 62,5 grados centígrados, sin embargo, la pasteurización a 72 grados centígrados antes de la liofilización mostró mayor retención de inmunoglobulinas. CONCLUSIONES: nuestros resultados sugieren que la liofilización de LHM pasteurizada es un método eficiente para la conservación en bancos de leche humana. Tanto la composición nutricional como la extensión de su vida útil y la aplicación de los dos procesos juntos proporcionan la ventaja de mantener las propiedades terapéuticas de la leche humana para mejorar la salud del recién nacido en estado vulnerable, desmedro o inmunosuprimido.

Evaluation of nutrients removal (NO3-N, NH3-N and PO4-P) with Chlorella vulgaris, Pseudomonas putida, Bacillus cereus and a consortium of these microorganisms in the treatment of wastewater effluents.

In this research removal of NH3-N, NO3-N and PO4-P nutrients from municipal wastewater was studied, using Chlorella vulgaris, Pseudomonas putida, Bacillus cereus and an artificial consortium of them. The objective is to analyze the performance of these microorganisms and their consortium, which has not been previously studied for nutrient removal in municipal wastewater. A model wastewater was prepared simulating the physicochemical characteristics found at the wastewater plant in Chapala, Mexico. Experiments were carried out without adding an external carbon source. Results indicate that nutrient removal with Chlorella vulgaris was the most efficient with a removal of 24.03% of NO3-N, 80.62% of NH3-N and 4.30% of PO4-P. With Bacillus cereus the results were 8.40% of NO3-N, 28.80% of NH3-N and 3.80% of PO4-P. The removals with Pseudomonas putida were 2.50% of NO3-N, 41.80 of NH3-N and 4.30% of PO4-P. The consortium of Chlorella vulgaris-Bacillus cereus-Pseudomonas putida removed 29.40% of NO3-N, 4.2% of NH3-N and 8.4% of PO4-P. The highest biomass production was with Bacillus cereus (450 mg/l) followed by Pseudomonas putida (444 mg/l), the consortium (205 mg/l) and Chlorella vulgaris (88.9 mg/l). This study highlights the utility of these microorganisms for nutrient removal in wastewater treatments.

Effect of Agave tequilana juice on cell wall polysaccharides of three Saccharomyces cerevisiae strains from different origins.

In this study, a characterization of cell wall polysaccharide composition of three yeasts involved in the production of agave distilled beverages was performed. The three yeast strains were isolated from different media (tequila, mezcal and bakery) and were evaluated for the beta(1,3)-glucanase lytic activity and the beta-glucan/ mannan ratio during the fermentation of Agave tequilana juice and in YPD media (control). Fermentations were performed in shake flasks with 30 g l(-1) sugar concentration of A. tequilana juice and with the control YPD using 30 g l(-1) of glucose. The three yeasts strains showed different levels of beta-glucan and mannan when they were grown in A. tequilana juice in comparison to the YPD media. The maximum rate of cell wall lyses was 50% lower in fermentations with A. tequilana juice for yeasts isolated from tequila and mezcal than compared to the bakery yeast.

Occurrence and parasitism of aphids(Hemiptera: Aphididae)on cultivars of irrigated oat(Avena spp. )in São Carlos, Brazil

Foram avaliadas as interações entre afídeos e seus himenópteros parasitóides em cultivares de aveia irrigada, como também a resposta de diferentes cultivares em relação resistência à estes afídeos e a influência nas relações hospedeiro/parasitóide durante dois anos em São Carlos, SP, Brasil. Rhopalosiphum padi (L.) foi o afídeo predominante ao longo do estudo, enquanto as outras espécies raramente foram encontradas. Foram observadas cinco espécies de himenópteros parasitóides: três parasitóides primários, Lysiphlebus testaceipes (Cresson), Aphidius colemani (Viereck) e Diaeretiella rapae (M'Intosh) e dois hiperparasitóides, Syrphophagus aphidivorus (Myer) and Alloxysta brassicae (Ashmead). A cultivar UPF 86081 apresentou resultados significativos quanto à baixa infestação por Rhopalosiphum padi e maiores taxas de parasitismo que a demais cultivares. Não foi observado efeito significativo na variação de porcentagem de emergência de parasitóides nos afídeos mumificados ao longo deste estudo.

The construction of the ethnozoological dominion insect by the inhabitants of the village of Pedra Branca, Santa Terezinha, Bahia state, Brazil - DOI: 10.4025/actascibiolsci.v26i1.1662 / A construção do domínio etnozoológico inseto pelos moradores do povoado de Pedra Branca, Santa Terezinha, Estado da Bahia - DOI: 10.4025/actascibiolsci.v26i1.1662

This article discusses the perception and the construction of the ethnozoological dominion insect by the inhabitants of Pedra Branca village, Santa Terezinha, central-west region of Bahia. Data were obtained from February to May 2001 through open and semi-structured interviews, and also by observations of behaviors of 74 males and 79 females, from 4 to 108 years old. It was noted that the linguistic label insect is used as a broad ethnotaxonomic category that brings together different organisms not systematically related (rat, snake, lizard, etc.), besides the Linnean insects. According to the data recorded both in this village and from the literature, it could be hypothesized that the dominion insect occurs as a pattern in the ethnobiological classification systems. An apprenticeship process based on suitable sensorial stimulus could lead people change their attitudes toward insects, making them more bearable to live together with these organisms

Discute-se a percepção e a construção do domínio etnozoológico inseto por moradores do povoado de Pedra Branca, município de Santa Terezinha, localizado na região centro-oeste do Estado da Bahia. Dados foram obtidos de fevereiro a maio de 2001, realizando-se entrevistas abertas, semi-estruturadas e observações comportamentais com 74 homens e 79 mulheres, cujas idades variaram de 4 a 108 anos. Registrou-se que o termo inseto é utilizado como uma categoria etnotaxonômica ampla que reúne diferentes organismos não sistematicamente relacionados (rato, cobra, lagartixa, etc.), além dos insetos lineanos. Com base nas informações registradas no povoado e em dados da literatura, pode-se levantar a suposição de que o domínio inseto ocorre como um padrão nos sistemas de classificação etnobiológicos. Sugere-se que um processo de aprendizagem baseado em estímulos sensoriais adequados poderia levar a mudanças de atitudes dos indivíduos com relação aos insetos, tornando-os mais toleráveis ao convívio com esses organismos