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Ligninases and hemicellulases are crucial as accessory enzymes to increase the enzymatic hydrolysis of lignocellulose, boosting sugars production from which biofuels and bioproducts could be obtained. In order to find new sources of these accessory enzymes, this study evaluates the potential of laccase and mannanase enzymes from Streptomyces ipomoeae for improving the conventional hydrolysis with commercial cellulases of steam-pretreated softwood. For that, different laccase treatment and mannanase supplementation strategies were performed. S. ipomoeae laccase increased both glucose and xylose production (17.8% and 9.3%, respectively), which was attributed to a removal of phenols of 29%. Moreover, the combination of laccase and alkaline extraction produced a lignin reduction of 16.2%, improving the glucose and xylose production by almost 41.3% and 44.9%, respectively. On the other hand, the supplementation of S. ipomoeae mannanase to the hydrolysis 24 h before the addition of cellulases increased the glucose (18.4%), xylose (12.3%), and mannose (47.2%) production. [ABSTRACT FROM AUTHOR]

Eastern Texas straddles a precipitation zone that transitions from semi-arid grasslands to the humid, rainy conditions of the northern Gulf Coast. While several studies have quantified the changing magnitude and frequency of daily extreme events, the paucity of hourly datasets have limited insight into how the growing proportion of rainfall exceeding hourly soil infiltration capacity has and will exacerbate the state’s droughts. This paper builds on previous analysis, deploying algorithms with a temporal dimension to calculate soil moisture scarcity from evapotranspiration and precipitation data based on FAO-56 methodology and then introduces a daily estimate of the proportion of precipitation that flows off the ground surface rather than replenishing moisture deficits for soils with three different infiltrative capacities at 12 observation sites. The comparison of subsequent time-series regression analyses showed that absorptive soils in east Texas have experienced modest, though mostly statistically insignificant, acceleration in drought trends after the incorporation of hourly rainfall intensity data: for the 24 soil samples (out of 36) with saturated hydraulic conductivity K sat rates greater than 4.5 mm per hour, 14 had accelerated drying trends, five showed no change, and the remaining five displayed more gradual changes relative to their baseline trend magnitudes. [ABSTRACT FROM AUTHOR]

Homogenised climatological series and gridded data are the basis for climate monitoring and climate change detection. Considering this, monthly mean temperatures from 122 Croatian stations were homogenised, and high-resolution monthly gridded data were developed for the 1981–2018 period. Homogenisation needs to be performed on stations from the same climate region; therefore, hierarchical clustering is introduced to define those climate regions in Croatia. The breaks of homogeneity were detected by the standard normal homogeneity test on 54 stations. Regression kriging was applied to produce monthly grids for each month in the analysed period. The quality of the interpolation assessed by leave-one-out cross-validation resulted in a root mean square error of 0.7 °C. The quality of spatial interpolation is supplemented with normalised error maps. The derived homogenised station data and monthly grids are necessary for national climate monitoring, the production of climate normals and the estimation of trends. After 1999, average annual anomalies from the 30-year climate standard normal 1981–2010 were positive and up to 1.4 °C warmer than the average and only occasionally negative. The measured amount, sign and significance of the trend were accurately captured on the trend maps calculated from the monthly maps. Significant strong warming was observed and mapped over the entire Croatian territory in April, June, July, August and November. It was stronger inland than on the coast. Annual trends were significant and ranged from 0.3 °C/decade to 0.7 °C/decade. There was no observational evidence of enhanced elevation-dependent warming over elevations from 750 to 1594 m. [ABSTRACT FROM AUTHOR]

The Mid-Atlantic region of the USA has experienced increasing annual precipitation amounts in recent decades, along with more frequent extreme events of greater magnitude. Unlike many US regions that have suffered increasing drought conditions from higher evapotranspiration demand, positive trends in the Mid-Atlantic accumulated precipitation are greater than the recent increases in reference evapotranspiration. The temporal correlation between precipitation events and soil moisture capacity is essential for determining how the nature of drought has changed in the region. This analysis has shown that soil moisture scarcity has declined in nine of ten subregions of the Mid-Atlantic that were analyzed from 1985 to 2019. Two algorithms were deployed to draw this conclusion: Climatol enabled the use of the FAO-56 Penman-Monteith equation on daily observation station data for which complete records were unavailable, and the second algorithm calculated soil moisture levels on a daily basis, more accurately capturing drought conditions than common methods using weekly or monthly summaries. Although the declining drought trends were not statistically significant, a result of more extreme events and higher evapotranspiration rates, the inclusion of direct data from an expanded set of locations provides greater clarity from the trends, allowing policymakers and landowners to anticipate changes in future Mid-Atlantic irrigation water demand. [ABSTRACT FROM AUTHOR]

A newly identified extracellular laccase produced by Streptomyces ipomoea CECT 3341 (SilA) was cloned and overexpressed, and its physicochemical characteristics assessed together with its capability to decolorize and detoxify an azotype dye. Molecular analysis of the deduced sequence revealed that SilA contains a TAT-type signal peptide at the N-terminus and only two cupredoxine domains; this is consistent with reports describing two other Streptomyces laccases but contrasts with most laccases, which contain three cupredoxine domains. The heterologous expression and purification of SilA revealed that the homodimer is the only active form of the enzyme. Its stability at high pH and temperature, together with its resistance to high concentrations of NaCl and to typical laccase inhibitors such as sodium azide confirmed the unique properties of this novel laccase. The range of substrates that SilA is able to oxidize was found to be pH-dependent; at alkaline pH, SilA oxidized a wide range of phenolic compounds, including the syringyl and guayacil moieties derived from lignin. The oxidative potential of this enzyme to use phenolic compounds as natural redox mediators was shown through the coordinated action of SilA and acetosyringone (as mediator), which resulted in the complete detoxification of the azo-type dye Orange II. [ABSTRACT FROM AUTHOR]

Colonies of the fish pathogen Flavobacterium psychrophilum have gliding motility in media with low agar concentrations. Although gliding motility, particularly in Flavobacterium johnsoniae, has been well-studied, little is known about its regulation by environmental factors. The work described here shows that the ability of F. psychrophilum to spread over surfaces depends on nutrient availability. In fact, as the nutrient contents of the medium decreased, spreading was favored and the diameter of the colonies increased. Macroscopy examination revealed modifications in colony morphology as nutrient depletion increased: from a dense and defined colony to the formation of microcolonies inside a general colony structure. Additionally, colony expansion dynamics and population density across the colony radius varied inversely with bacterial biomass production. Motility was an immediate response when bacteria were transferred from a rich to a more diluted medium. Our results suggest that, when nutrients are limiting, F. psychrophilum activates a specific growth mode that enables it to colonize surfaces by means of gliding motility. The use of diluted media allowed the differentiation, among previously isolated F. psychrophilum non-gliding mutants, of those completely unable to glide and those with only partially impaired gliding ability.