Efficiency of rice straw lignocelluloses degradability by Aspergillus terreus ATCC 74135 in solid state fermentation

The ability of Aspergillus terreus for the production of cellulolytic enzymes and reduction of lignocellulose contents of rice straw in solid state fermentation was investigated in this study. Results suggested that, 8 days fermentation was appropriate, with enzymes activities as follows: FPase = 410.76 U/gDM, CMCase = 351.96U/gDM, -glucosidase = 16.37 U/gDM, xylanase = 6166.01 U/gDM and amyloglucosidase = 425.04 U/gDM (with maximum 993.71 U/gDM on day 6). In addition, the solid state fermentation significantly (P < 0.01) reduced the concentrations of NDF, ADF, cellulose and hemicellulose in the rice straw by 19.96, 13.8, 16.32 and 32.87%, respectively. The high degradation of the hemicellulose was reflected by the high activity of xylanase enzyme, which hydrolyses xylan in hemicellulose to xylose. Higher reducing sugar and microbial cell mass productions were also obtained after 8 days fermentation. Present data showed that, A. terreus is capable of producing high quantity of cellulolytic enzymes for the reduction of lignocellulose contents of biomass in a shorter incubation time when compared with the previously reported for biological treatment of agricultural by-products using white rot fungi.Key words: Aspergillus terreus, biomass, biological treatment, enzyme activity, solid state fermentation

Effects of Aspergillus niger (K8) on nutritive value of rice straw

The objective of this study was to evaluate the use of solid state fermentation for the improvement of the quality of rice straw as animal feed. Rice straw was fermented using Aspergillus niger (K8) with and without additional nitrogen source (urea). Cellulose, hemicelluloses, organic matter (OM), dry matter (DM), acid detergent fibre (ADF), neutral detergent fibre (NDF) and acid detergent lignin (ADL) contents of rice straw were determined before and after 10 days of fermentation. Fermentation has significant (P < 0.01) effect on NDF, but not ADF and ADL contents. Addition of urea as nitrogen source significantly reduced (P < 0.01) the NDF and hemicellulose contents of fermented rice straw. Cellulose content of the rice straw was not affected (P > 0.05), but crude protein (CP) increased significantly (P < 0.01) after fermentation. In vitro gas production technique was used to evaluate the effect of the biological treatment on activity of rumen microorganisms. Fermentation of rice straw using A. niger significantly reduced total gas production (P < 0.01), DM disappearance (P < 0.01) and acetate, propionate and  total volatile fatty acids (VFA) production (P < 0.05). Results of the present study showed that solid state fermentation of rice straw using A. niger reduced lignocellulose content, but has negative effect on microbial activity in the rumen ecosystem, presumably due to antagonistic activity of A. niger, or other intermediate products from the fermentation, on the rumen microorganisms.Key words: Aspergillus niger, biomass, solid state fermentation, biological treatment, in vitro gas production

SARS-CoV-2 structural coverage map reveals viral protein assembly, mimicry, and hijacking mechanisms

We modeled 3D structures of all SARS-CoV-2 proteins, generating 2,060 models that span 69% of the viral proteome and provide details not available elsewhere. We found that ˜6% of the proteome mimicked human proteins, while ˜7% was implicated in hijacking mechanisms that reverse post-translational modifications, block host translation, and disable host defenses; a further ˜29% self-assembled into heteromeric states that provided insight into how the viral replication and translation complex forms. To make these 3D models more accessible, we devised a structural coverage map, a novel visualization method to show what is-and is not-known about the 3D structure of the viral proteome. We integrated the coverage map into an accompanying online resource (https://aquaria.ws/covid) that can be used to find and explore models corresponding to the 79 structural states identified in this work. The resulting Aquaria-COVID resource helps scientists use emerging structural data to understand the mechanisms underlying coronavirus infection and draws attention to the 31% of the viral proteome that remains structurally unknown or dark

Effects of Cowpea mottle virus and Cucumber mosaic virus on six Soybean (Glycine max L.) cultivars

The study was carried out to determine the comparative pathogenic response of six cultivars of soybean; TGx 1844-18E, TGx 1448-2E, TGx 1910-8F, TGx 1019-2EN, TGx 1910-8F and TGx 1876-4E to single and mixed infections with cowpea mottle virus and cucumber mosaic virus. The experiment was conducted in the screenhouse at the crop production pavilion, Faculty of Agriculture, University of Ilorin, Ilorin, Kwara state Nigeria. The results of the experiment revealed that all soybean cultivars were susceptible to single and mixed infection of the two viruses but to seemingly different extent. The single infection with cowpea mottle virus (CMeV), however, caused the most severe symptoms on the soybean cultivars. Cucumber mosaic virus (CMV) alone was not as severe as the CMeV. The mixed infection of CMeV and CMV did not cause higher severity than CMeV alone indicating that there was little or no synergistic effect between the two viruses on soybean

Significance of herpesvirus immediate early gene expression in cellular immunity to cytomegalovirus infection

Interstitial pneumonia linked with reactivation of latent human cytomegalovirus due to iatrogenic immunosuppression can be a serious complication of bone marrow transplantation therapy of aplastic anaemia and acute leukaemia1. Cellular immunity plays a critical role in the immune surveillance of inapparent cytomegalovirus infections in man and the mouse1−7. The molecular basis of latency, however, and the interaction between latently or recurrently infected cells and the immune system of the host are poorfy understood. We have detected a so far unknown antigen in the mouse model. This antigen is found in infected cells in association with the expression of the herpesvirus 'immediate early' genes and is recognized by cytolytic T lymphocytes (CTL)8. We now demonstrate that an unexpectedly high proportion of the CTL precursors generated in vivo during acute murine cytomegalovirus infection are specific for cells that selectively synthesize immediate early proteins, indicating an immunodominant role of viral non-structural proteins

Feigenbaum graphs: a complex network perspective of chaos

The recently formulated theory of horizontal visibility graphs transforms time series into graphs and allows the possibility of studying dynamical systems through the characterization of their associated networks. This method leads to a natural graph-theoretical description of nonlinear systems with qualities in the spirit of symbolic dynamics. We support our claim via the case study of the period-doubling and band-splitting attractor cascades that characterize unimodal maps. We provide a universal analytical description of this classic scenario in terms of the horizontal visibility graphs associated with the dynamics within the attractors, that we call Feigenbaum graphs, independent of map nonlinearity or other particulars. We derive exact results for their degree distribution and related quantities, recast them in the context of the renormalization group and find that its fixed points coincide with those of network entropy optimization. Furthermore, we show that the network entropy mimics the Lyapunov exponent of the map independently of its sign, hinting at a Pesin-like relation equally valid out of chaos.Comment: Published in PLoS ONE (Sep 2011

Interleukin-1 regulates multiple atherogenic mechanisms in response to fat feeding

Background: Atherosclerosis is an inflammatory process that develops in individuals with known risk factors that include hypertension and hyperlipidaemia, influenced by diet. However, the interplay between diet, inflammatory mechanisms and vascular risk factors requires further research. We hypothesised that interleukin-1 (IL-1) signaling in the vessel wall would raise arterial blood pressure and promote atheroma. Methodology/Principal Findings: Apoe(-/-) and Apoe(-/-)/IL-1R1(-/-) mice were fed high fat diets for 8 weeks, and their blood pressure and atherosclerosis development measured. Apoe(-/-)/IL-R1(-/-) mice had a reduced blood pressure and significantly less atheroma than Apoe(-/-) mice. Selective loss of IL-1 signaling in the vessel wall by bone marrow transplantation also reduced plaque burden (p<0.05). This was associated with an IL-1 mediated loss of endothelium-dependent relaxation and an increase in vessel wall Nox 4. Inhibition of IL-1 restored endothelium-dependent vasodilatation and reduced levels of arterial oxidative stress. Conclusions/Significance: The IL-1 cytokine system links atherogenic environmental stimuli with arterial inflammation, oxidative stress, increased blood pressure and atherosclerosis. This is the first demonstration that inhibition of a single cytokine can block the rise in blood pressure in response to an environmental stimulus. IL-1 inhibition may have profound beneficial effects on atherogenesis in man

Large emissions from floodplain trees close the Amazon methane budget

Wetlands are the largest global source of atmospheric methane (CH4), a potent greenhouse gas. However, methane emission inventories from the Amazon floodplain, the largest natural geographic source of CH4 in the tropics, consistently underestimate the atmospheric burden of CH4 determined via remote sensing and inversion modelling, pointing to a major gap in our understanding of the contribution of these ecosystems to CH4 emissions. Here we report CH4 fluxes from the stems of 2,357 individual Amazonian floodplain trees from 13 locations across the central Amazon basin. We find that escape of soil gas through wetland trees is the dominant source of regional CH4 emissions. Methane fluxes from Amazon tree stems were up to 200 times larger than emissions reported for temperate wet forests6 and tropical peat swamp forests, representing the largest non-ebullitive wetland fluxes observed. Emissions from trees had an average stable carbon isotope value (δ13C) of −66.2 ± 6.4 per mil, consistent with a soil biogenic origin. We estimate that floodplain trees emit 15.1 ± 1.8 to 21.2 ± 2.5 teragrams of CH4 a year, in addition to the 20.5 ± 5.3 teragrams a year emitted regionally from other sources. Furthermore, we provide a ‘top-down’ regional estimate of CH4 emissions of 42.7 ± 5.6 teragrams of CH4 a year for the Amazon basin, based on regular vertical lower-troposphere CH4 profiles covering the period 2010–2013. We find close agreement between our ‘top-down’ and combined ‘bottom-up’ estimates, indicating that large CH4 emissions from trees adapted to permanent or seasonal inundation can account for the emission source that is required to close the Amazon CH4 budget. Our findings demonstrate the importance of tree stem surfaces in mediating approximately half of all wetland CH4 emissions in the Amazon floodplain, a region that represents up to one-third of the global wetland CH4 source when trees are combined with other emission sources