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Dimorphic species of Mucor, which are cosmopolitan fungi belonging to subphylum Mucoromycotina, are metabolically versatile. Some species of Mucor are sources of biotechnological products, such as biodiesel from Mucor circinelloides and expression of heterologous proteins from Mucor lusitanicus. Furthermore, Mucor lusitanicus has been described as a model for understanding mucormycosis infections. However, little is known regarding the relationship between Mucor lusitanicus and other soil inhabitants. In this study, we investigated the potential use of Mucor lusitanicus as a biocontrol agent against fungal phytopathogens, namely Fusarium oxysporum f. sp. lycopersici, Fusarium solani, and Alternaria solani, which destroy economically important crops. Results showed that aerobic cell-free supernatants of the culture broth (SS) from Mucor lusitanicus inhibited the growth of the fungal phytopathogens in culture, soil, and tomato fruits. The SS obtained from a strain of Mucor lusitanicus carrying the deletion of rfs gene, which encodes an enzyme involved in the synthesis of siderophore rhizoferrin, had a decreased inhibitory effect against the growth of the phytopathogens. Contrarily, this inhibitory effect was more evident with the SS from an rfs-overexpressing strain compared to the wild-type. This study provides a framework for the potential biotechnological use of the molecules secreted from Mucor lusitanicus in the biocontrol of fungal phytopathogens.

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Plants being sessile organisms are exposed to various biotic and abiotic factors, thus causing stress. The Pseudomonas aeruginosa bacterium is an opportunistic pathogen for animals, insects, and plants. Direct exposure of Arabidopsis thaliana to the P. aeruginosa PAO1 strain induces plant death by producing a wide variety of virulence factors, which are regulated mainly by quorum sensing systems. Besides virulence factors, P. aeruginosa PAO1 also produces cyclodipeptides (CDPs), which possess auxin-like activity and promote plant growth through activation of the target of the rapamycin (AtTOR) pathway. On the other hand, plant defense mechanisms are regulated through the production of phytohormones, such as salicylic acid (SA) and jasmonic acid (JA), which are induced in response to pathogen-associated molecular patterns (PAMPs), activating defense genes associated with SA and JA such as PATHOGENESIS-RELATED-1 (PR-1) and LIPOXYGENASE2 (LOX2), respectively. PR proteins are suggested to play critical roles in coordinating the Systemic Acquired Resistance (SAR). In contrast, LOX proteins (LOX2, LOX3, and LOX4) have been associated with the production of JA by producing its precursors, oxylipins. The activation of defense mechanisms involves signaling cascades such as Mitogen-Activated Protein Kinases (MAPKs) or the TOR pathway as a switch for re-directing energy towards defense or growth. In this work, we challenged A. thaliana (wild type, mpk6 or mpk3 mutants, and overexpressing TOR) seedlings with P. aeruginosa PAO1 strains to identify the role of bacterial CDPs in the plant immune response. Results showed that the pre-exposure of these Arabidopsis seedlings to CDPs significantly reduced plant infection of the pathogenic P. aeruginosa PAO1 strains, indicating that plants that over-express AtTOR or lack MPK3/MPK6 protein-kinases are more susceptible to the pathogenic effects. In addition, CDPs induced the GUS activity only in the LOX2::GUS plants, indicative of JA-signaling activation. Our findings indicate that the CDPs are molecules that trigger SA-independent and JA-dependent defense responses in A. thaliana; hence, bacterial CDPs may be considered elicitors of the Arabidopsis immune response to pathogens.

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The pathogenic bacterium Pseudomonas aeruginosa possesses high metabolic versatility, with its effectiveness to cause infections likely due to its well-regulated genetic content. P. aeruginosa PAO1 has at least six fadD paralogous genes, which have been implicated in fatty acid (FA) degradation and pathogenicity. In this study, we used mutagenesis and a functional approach in P. aeruginosa PAO1 to determine the roles of the fadD4 gene in acyclic terpene (AT) and FA assimilation and on pathogenicity. The results indicate that fadD4 encodes a terpenoyl-CoA synthetase utilized for AT and FA assimilation. Additionally, mutations in fadD paralogs led to the modification of the quorum-sensing las/rhl systems, as well as the content of virulence factors pyocyanin, biofilm, rhamnolipids, lipopolysaccharides (LPS), and polyhydroxyalkanoates. In a Caenorhabditis elegans in vivo pathogenicity model, culture supernatants from the 24-h-grown fadD4 single mutant increased lethality compared to the PAO1 wild-type (WT) strain; however, the double mutants fadD1/fadD2, fadD1/fadD4, and fadD2/fadD4 and single mutant fadD2 increased worm survival. A correlation analysis indicated an interaction between worm death by the PAO1 strain, the fadD4 mutation, and the virulence factor LPS. Fatty acid methyl ester (FAME) analysis of LPS revealed that a proportion of the LPS and FA on lipid A were modified by the fadD4 mutation, suggesting that FadD4 is also involved in the synthesis/degradation and modification of the lipid A component of LPS. LPS isolated from the fadD4 mutant and double mutants fadD1/fadD4 and fadD2/fadD4 showed a differential behavior to induce an increase in body temperature in rats injected with LPS compared to the WT strain or from the fadD1 and fadD2 mutants. In agreement, LPS isolated from the fadD4 mutant and double mutants fadD1/fadD2 and fadD2/fadD4 increased the induction of IL-8 in rat sera, but IL1-ß cytokine levels decreased in the double mutants fadD1/fadD2 and fadD1/fadD4. The results indicate that the fadD genes are implicated in the degree of pathogenicity of P. aeruginosa PAO1 induced by LPS-lipid A, suggesting that FadD4 contributes to the removal of acyl-linked FA from LPS, rendering modification in its immunogenic response associated to Toll-like receptor TLR4. The genetic redundancy of fadD is important for bacterial adaptability and pathogenicity over the host.

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Multi-walled carbon nanotubes (MWCNTs) are of multidisciplinary scientific interest due to their exceptional physicochemical properties and a broad range of applications. However, they are considered potentially toxic nanoparticles when they accumulate in the environment. Given their ability to oxidize resistant polymers, mycorremediation with lignocellulolytic fungi are suggested as biological alternatives to the mineralization of MWCNTs. Hence, this study involves the ability of two fungi specie to MWCNTs biotransformation by laccase and peroxidases induction and evaluation in vivo of its toxicity using Caenorhabditis elegans worms as a model. Results showed that the fungi Penicillium chrysogenum and Pleurotus ostreatus were capable to grow on media with MWCNTs supplemented with glucose or lignin. Activities of lignin-peroxidase, manganese-peroxidase, and laccase in cultures of both fungi were induced by MWCNTs. Raman, FTIR spectroscopy, HR-TEM, and TGA analyses of the residue from the cultures of both fungi revealed structural modifications on the surface of MWCNTs and its amount diminished, correlating the MWCNTs structural modifications with the laccase-peroxidase activities in the fungal cultures. Results indicate that the degree of toxicity of MWCNTs on the C. elegans model was enhanced by the structure modification associated with the fungal ligninolytic activity. The toxic effect of MWCNTs on the in vivo model of worms reveals the increment of reactive oxygen species as a mechanism of toxicity. Findings indicate that the MWCNTs can be subject in nature to biotransformation processes such as the fungal metabolism, which contribute to modify their toxicity properties on susceptible organisms and contributing to environmental elimination.

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This work examines the strategies adopted by an arbuscular mycorrhizal symbiotic system to ameliorate environmental Pb stress by examining the concentrations of P, Fe, and Pb in the fungal microstructures and the host's root. In vitro cultures of Ri-T DNA-transformed carrot (Daucus carota L.) roots were inoculated with Glomus intraradices and treated with Pb(NO3)2 solution and the extraradical spores and mycelia (S/M) and the root with the vesicles, mycelia, and root cells were subsequently analyzed by polarized energy dispersive x-ray fluorescence (PEDXRF) spectrometry. Upon Pb treatment, within the root, the percentages of mycorrhizal colonization, the vesicles, and mycelia increased as well as the areas of the vesicles and the (extraradical) spores, although the number of spores and arbuscules decreased. The S/M and the mycorrhizal root showed enhanced concentrations of Pb, Fe, and P. These were particularly marked for Fe in the Pb-treated cultures. This indicates a synergistic relationship between the arbuscular mycorrhizal fungus and the host that confers a higher Pb tolerance to the latter by the induction of higher Fe absorption in the host. The intraradical vesicle, mycelia, and arbuscule numbers are interpreted as a "tactic to divert" the intraradical Pb traffic away from the root cells to the higher affinity cell walls of the arbuscular mycorrhizal fungi (AMF) microstructures in the apoplast. The results of this work show that the symbiosis between the AMF G. intraradices and the host plant D. carota distinctly improves the latter's Pb tolerance, and imply that the appropriate metal tolerant host-AMF combinations could be employed in process designs for the phytoremediation of Pb.

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Objetivo: Determinar la eficacia del abordaje preperitoneal tipo Nyhus con malla como técnica de primera elección frente a la técnica de Lichtenstein en el Servicio de Cirugía del Hospital Regional Virgen de Fátima de Chachapoyas-Amazonas. Material y Métodos: Tipo de estudio, descriptivo, longitudinal, retrospectivo y comparativo. Considerando 147 pacientes sometidos a hernioplastía durante Julio de 2011 a Julio de 2014, de los cuales en 84 pacientes se empleó la técnica quirúrgica Abordaje Preperitoneal tipo Nyhus con malla (ANP) y en 63 la técnica de Lichtenstein (LICH), tomando en cuenta las variables: tipo de hernia inguinal, estancia hospitalaria, grado de inguinodinea, restricción física por disconfort, complicaciones, recidiva y tiempo operatorio. Resultados: De los 84 pacientes operados con la técnica ANP 54 (64 por ciento) eran del sexo masculino y 30 (36 por ciento) de sexo femenino; de los 63 pacientes operados con la técnica LICH 45 (72 por ciento) eran del sexo masculino y 18 (28 por ciento) del sexo femenino. Se corrigió con APN 39 (46 por ciento) hernias inguinales indirectas, 23 (28 por ciento) directas, 9 (11 por ciento) crurales y 13 (15 por ciento) en pantalón. Se corrigió con LICH 30 (48 por ciento) hernias inguinales indirectas, 25 (40 por ciento) directas, 4 (6 por ciento) crurales y 4 (6 por ciento) en pantalón. La Inguinodinea (dolor crónico> 30 días) se presentó como leve en 45 casos (54 por ciento) y moderado 2 (2 por ciento) casos con APN, mientras que 34 casos leves (54 por ciento) y 6 casos moderados (10 por ciento) con LICH. La restricción física al 14avo día fueron de 2 casos (2 por ciento) para APN y 4 (6 por ciento) casos para LICH. La estancia hospitalaria mayoritariamente fue de < de 24 horas, con ambas técnicas verificándose 41 casos (48 por ciento) para APN y 31 casos (49 por ciento) para LICH. El tiempo operatorio en APN fue de 47.61 +/- 11.03 minutos y con LICH 49.13 +/- 7.95 minutos. La recidiva a 2 años con APN 1...

Objectives: To determine the efficacy of preperitoneal approach Nyhus type mesh as technique of choice versus Lichtenstein technique in the Surgery Department of Regional Hospital Virgen de Fatima at Chachapoyas-Amazonas. Material and Methods: Typo study, descriptive, longitudinal, retrospective and comparative. Whereas 147 patients undergoing hernia repair during July 2011 to July 2014, of which 84 patients the surgical technique was used Preperitoneal approach Nyhus type mesh (ANP) and 63 Lichtenstein technique (LICH), taking into account the variables: type of inguinal hernia, hospital stay, degree of inguinodinea, physical restraint by discomfort, complications, recurrence and operative time. Results: Of the 84 patients operated with APN technique 54 (64 per cent) were male and 30 (36 per cent) were female; of the 63 patients operated with LICH technique 45 (72 per cent) were male and 18 (28 per cent) were females. It was corrected with APN 39 (46 per cent) Indirect inguinal hernias, 23 (28 per cent) direct, 9 (11 per cent) femoral and 13 (15 per cent) in trousers. It was corrected with LICH 30 (48 per cent) Indirect inguinal hernias, 25 (40 per cent) direct, 4 (6 per cent) femoral and 4 (6 per cent) in pants. The Inguinodinea (chronic pain > 30 days) was presented as mild in 45 cases (54 per cent) and moderate 2 (2 per cent) cases with APN, while 34 mild cases (54 per cent) and 6 moderate cases (10 per cent) with LICH. Physical restraint the 14th day were 2 cases (2 per cent) for APN and 4 (6 per cent) cases for LICH. The hospital stay was mostly <24 hours, with both techniques verifying 41 cases (48 per cent) for APN and 31 cases (49 per cent) for LICH. The operative time in APN was 47.61 +/- 11.03 minutes and 49.13 +/- 7.95 LICH minutes. The recurrence at 2 years with APN 1 case (2 per cent) and 2 cases (4 per cent) with LICH. As for the relationship level of experience of the surgeon with surgical technique used, 72 per cent of interventions...

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BACKGROUND: Arbuscular mycorrhizal fungi (AMF) increase the uptake of minerals from the soil, thus improving the growth of the host plant. Nitrogen (N) is a main mineral element for plant growth, as it is an essential component of numerous plant compounds affecting fruit quality. The availability of N to plants also affects the AMF-plant interaction, which suggests that the quality of fruits could be affected by both factors. The objective of this study was to evaluate the influence of three N treatments (3, 6 and 18 mmol L(-1)) in combination with inoculation with the AMF Glomus intraradices on the quality of strawberry fruits. The effects of each factor and their interaction were analysed. RESULTS: Nitrogen treatment significantly modified the concentrations of minerals and some phenolic compounds, while mycorrhization significantly affected some colour parameters and the concentrations of most phenolic compounds. Significant differences between fruits of mycorrhizal and non-mycorrhizal plants were found for the majority of phenolic compounds and for some minerals in plants treated with 6 mmol L(-1) N. The respective values of fruits of mycorrhizal plants were higher. CONCLUSION: Nitrogen application modified the effect of mycorrhization on strawberry fruit quality.

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Del total de los predios de la Facultad de Ciencias Agricolas y Pecuarias el 29,46 por ciento, estan ocupadas por infraestructura, zonas urbanas, politecnico militar y el basurero municipal. Zonas aptas: tiene limitaciones de agua de riego y presencia de pedregosidad que dificultan la mecanizacion. Zonas moderadamente aptas, algorrobo y eucalipto en las zonas que tienen pendientes la limitacion es la falta de agua. Zonas marginalmente aptas, maiz zonas de pendiente entre 10-5 por ciento no tienen agua de riego. Zonas No aptas, la principal limitacion es la pendiente mayor a 25 por ciento ademas que no existe agua de riego y existe pedregosidad...

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