Consensus Design of an Evolved High-Redox Potential Laccase

Among the broad repertory of protein engineering methods that set out to improve stability, consensus design has proved to be a powerful strategy to stabilize enzymes without compromising their catalytic activity. Here, we have applied an in-house consensus method to stabilize a laboratory evolved high-redox potential laccase. Multiple sequence alignments were carried out and computationally refined by applying relative entropy and mutual information thresholds. Through this approach, an ensemble of 20 consensus mutations were identified, 18 of which were consensus/ancestral mutations. The set of consensus variants was produced in Saccharomyces cerevisiae and analyzed individually, while site directed recombination of the best mutations did not produce positive epistasis. The best single variant carried the consensus-ancestral A240G mutation in the neighborhood of the T2/T3 copper cluster, which dramatically improved thermostability, kinetic parameters and secretion.This study is based upon work funded by and the Spanish Government projects BIO2013-43407-R-DEWRY and BIO2016- 79106-R-Lignolution. BG-F was supported by a FPI national fellowship BES-2014-068887

Strength, jumping, and change of direction speed asymmetries are not associated with athletic performance in elite academy soccer players

The aims of the present study were twofold: 1) to measure inter-limb asymmetries from a battery of fitness tests in youth soccer players and, 2) determine the association between asymmetry and measures of athletic performance. Sixteen elite youth soccer players (14.7 ± 0.2 years) performed a single leg Abalakov test (ABK), change of direction (COD) test over 10 m (5 + 5) and 20 m (10 + 10), and an iso-inertial power test. Subjects also performed 10 m, 20 m and 30 m sprints and a bilateral countermovement jump (CMJ), which were correlated with all ABK, COD and iso-inertial asymmetry scores. A one-way repeated measures ANOVA showed significant differences between inter-limb asymmetry scores across multiple tests (p 0.05) between the different inter-limb asymmetry scores, and between asymmetry scores and athletic performance. These findings show the test-specific nature of asymmetries in youth soccer players, with the iso-inertial power test being the most sensitive in detecting asymmetry. Moreover, the results obtained suggest that inherent asymmetry in young soccer players did not negatively impact their performance

Properties of light resonances from unitarized Chiral perturbation theory: Nc behavior and quark mass dependence

We review the unitarization of Chiral Perturbation Theory with dispersion relations and how it describes meson-meson scattering data, generating light resonances whose mass, width and nature can be related to QCD parameters like quark masses and the number of colors.Comment: Invited review talk for the New Frontiers in QCD 2010, Yukawa International Program for Quark-Hadron Sciences (YIPQS), January 18 (Mon) - March 19 (Fri), 2010 Yukawa Institute for Theoretical Physics, Kyoto, Japan. To appear in Progress of Theoretical Physic

Ancestral Resurrection and Directed Evolution of Fungal Mesozoic Laccases

ABSTRACT Ancestral sequence reconstruction and resurrection provides useful information for protein engineering, yet its alliance with directed evolution has been little explored. In this study, we have resurrected several ancestral nodes of fungal laccases dating back 500 to 250 million years. Unlike modern laccases, the resurrected Mesozoic laccases were readily secreted by yeast, with similar kinetic parameters, a broader stability, and distinct pH activity profiles. The resurrected Agaricomycetes laccase carried 136 ancestral mutations, a molecular testimony to its origin, and it was subjected to directed evolution in order to improve the rate of 1,3- cyclopentanedione oxidation, a –diketone initiator commonly used in vinyl polymerization reactions. IMPORTANCE The broad variety of biotechnological uses of fungal laccases is beyond doubt (food, textiles, pulp and paper, pharma, biofuels, cosmetics, and bioremediation), and protein engineering (in particular, directed evolution) has become the key driver for adaptation of these enzymes to harsh industrial conditions. Usually, the first requirement for directed laccase evolution is heterologous expression, which presents an important hurdle and often a time-consuming process. In this work, we resurrected a fungal Mesozoic laccase node which showed strikingly high heterologous expression and pH stability. As a proof of concept that the ancestral laccase is a suitable blueprint for engineering, we performed a quick directed evolution campaign geared to the oxidation of the -diketone 1,3-cyclopentanedione, a poor laccase substrate that is used in the polymerization of vinyl monomers

Surgical clavicle reconstruction after aneurysmal bone cyst resection in a child: A simple method

The clavicle is an infrequent location for primary tumors in general, and aneurysmal bone cyst (ABC) of the clavicle is particularly rare. The challenge of the functional and esthetic result in the treatment of these lesions in the pediatric population is high when considering the reconstruction of critical bone defects. In this article, we present the case of a seven -year -old boy with an ABC in the middle third of the clavicle, treated by resection and reconstruction with free autograft of the fibula stabilized by using an intramedullary titanium nail. We offer a description of the used technique, considerations about treatment options in children, and a follow-up of more than two -and -a -half years

Influence of environmental heterogeneity on the distribution and persistence of a subterranean rodent in a highly unstable landscape

O.E.G was supported by the Marine Alliance for Science and Technology for Scotland.In this study we combine information from landscape characteristics, demographic inference and species distribution modelling to identify environmental factors that shape the genetic distribution of the fossorial rodent Ctenomys. We sequenced the mtDNA control region and amplified 12 microsatellites from 27 populations distributed across the Iberá wetland ecosystem. Hierarchical Bayesian modelling was used to construct phylogenies and estimate divergence times. We developed species distribution models to determine what climatic variables and soil parameters predicted species presence by comparing the current to the historic and predicted future distribution of the species. Finally, we explore the impact of environmental variables on the genetic structure of Ctenomys based on current and past species distributions. The variables that consistently correlated with the predicted distribution of the species and explained the observed genetic differentiation among populations included the distribution of well-drained sandy soils and temperature seasonality. A core region of stable suitable habitat was identified from the Last Interglacial, which is projected to remain stable into the future. This region is also the most genetically diverse and is currently under strong anthropogenic pressure. Results reveal complex demographic dynamics, which have been in constant change in both time and space, and are likely linked to the evolution of the Paraná River. We suggest that any alteration of soil properties (climatic or anthropic) may significantly impact the availability of suitable habitat and consequently the ability of individuals to disperse. The protection of this core stable habitat is of prime importance given the increasing levels of human disturbance across this wetland system and the threat of climate change.PostprintPeer reviewe

PANIC: the new panoramic NIR camera for Calar Alto

PANIC is a wide-field NIR camera, which is currently under development for the Calar Alto observatory (CAHA) in Spain. It uses a mosaic of four Hawaii-2RG detectors and covers the spectral range from 0.8-2.5 micron(z to K-band). The field-of-view is 30x30 arcmin. This instrument can be used at the 2.2m telescope (0.45arcsec/pixel, 0.5x0.5 degree FOV) and at the 3.5m telescope (0.23arcsec/pixel, 0.25x0.25 degree FOV). The operating temperature is about 77K, achieved by liquid Nitrogen cooling. The cryogenic optics has three flat folding mirrors with diameters up to 282 mm and nine lenses with diameters between 130 mm and 255 mm. A compact filter unit can carry up to 19 filters distributed over four filter wheels. Narrow band (1%) filters can be used. The instrument has a diameter of 1.1 m and it is about 1 m long. The weight limit of 400 kg at the 2.2m telescope requires a light-weight cryostat design. The aluminium vacuum vessel and radiation shield have wall thicknesses of only 6 mm and 3 mm respectively.Comment: This paper has been presented in the SPIE of Astronomical Telescopes and Instrumentation 2008 in Marseille (France

Bulk viscosity of low-temperature strongly interacting matter

We study the bulk viscosity of a pion gas in unitarized Chiral Perturbation Theory at low and moderate temperatures, below any phase transition to a quark-gluon plasma phase. We argue that inelastic processes are irrelevant and exponentially suppressed at low temperatures. Since the system falls out of chemical equilibrium upon expansion,a pion chemical potential must be introduced, so we extend the existing theory to include it. We control the zero modes of the collision operator and Landau's conditions of fit when solving the Boltzmann equation with the elastic collision kernel. The dependence of the bulk viscosity with temperature is reminiscent of the findings of Fernandez-Fraile and Gomez Nicola, while the numerical value is closer to that of Davesne. In the zero-temperature limit we correctly recover the vanishing viscosity associated to a non-relativistic monoatomic gas.Comment: 8 pages, 8 figure