On the origin of the mitochondrial genetic code: Towards a unified mathematical framework for the management of genetic information

The origin of the genetic code represents one of the most challenging problems in molecular evolution. The genetic code is an important universal feature of extant organisms and indicates a common ancestry of different forms of life on earth. Known variants of the genetic code can be mainly divided in mitochondrial and nuclear classes. Here we provide a new insight on the origin of the mitochondrial genetic code: we found that its degeneracy distribution can be explained by using a mathematical approach recently developed for the description of the Euplotes nuclear variant of the genetic code. The results point to a primeval mitochondrial genetic code composed of four base codons, which we call tesserae, that, among other features, exhibit outstanding error detection capabilities. The theoretical description suggests also a formulation of a plausible biological theory about the origin of protein coding. Such theory is based on the symmetry properties of hypothetical primeval chemical adaptors between nucleic acids and amino acids (ancient tRNA’s). Our paper provides a unified mathematical framework for different hypotheses on the origin of genetic coding. Also, it contributes to revisit our present view about the evolutionary steps that led to extant genetic codes by giving a new first-principles perspective on the difficult problem of the origin of the genetic code, and consequently, on the origin of life on earth

On the origin of the mitochondrial genetic code: Towards a unified mathematical framework for the management of genetic information

The origin of the genetic code represents one of the most challenging problems in molecular evolution. The genetic code is an important universal feature of extant organisms and indicates a common ancestry of different forms of life on earth. Known variants of the genetic code can be mainly divided in mitochondrial and nuclear classes. Here we provide a new insight on the origin of the mitochondrial genetic code: we found that its degeneracy distribution can be explained by using a mathematical approach recently developed for the description of the Euplotes nuclear variant of the genetic code. The results point to a primeval mitochondrial genetic code composed of four base codons, which we call tesserae, that, among other features, exhibit outstanding error detection capabilities. The theoretical description suggests also a formulation of a plausible biological theory about the origin of protein coding. Such theory is based on the symmetry properties of hypothetical primeval chemical adaptors between nucleic acids and amino acids (ancient tRNA's). Our paper provides a unified mathematical framework for different hypotheses on the origin of genetic coding. Also, it contributes to revisit our present view about the evolutionary steps that led to extant genetic codes by giving a new first-principles perspective on the difficult problem of the origin of the genetic code, and consequently, on the origin of life on earth

A role for circular code properties in translation

Circular codes represent a form of coding allowing detection/correction of frame-shift errors. Building on recent theoretical advances on circular codes, we provide evidence that protein coding sequences exhibit in-frame circular code marks, that are absent in introns and are intimately linked to the keto-amino transformation of codon bases. These properties strongly correlate with translation speed, codon influence and protein synthesis levels. Strikingly, circular code marks are absent at the beginning of coding sequences, but stably occur 40 codons after the initiator codon, hinting at the translation elongation process. Finally, we use the lens of circular codes to show that codon influence on translation correlates with the strong-weak dichotomy of the first two bases of the codon. The results can lead to defining new universal tools for sequence indicators and sequence optimization for bioinformatics and biotechnological applications, and can shed light on the molecular mechanisms behind the decoding process

La economía social y solidaria en las políticas públicas regionales. El caso del MERCOSUR

Desde la década de 1990, los países de América Latina construyeron nuevas herramientas comerciales con terceros países orientadas bajo los postulados del neoliberalismo. Este proceso se caracterizó por la revalorización de la dimensión económica acompañada por una pérdida de relevancia de las dimensiones política y social. En el marco de instituciones creadas con estos principios rectores, sin embargo, se fueron construyendo experiencias ancladas en los principios y valores de la economía social y solidaria (ESS). Con múltiples emprendimientos y con las cooperativas como unidad principal, este modelo se reconoce desde su origen como una propuesta teórica y política que busca desarrollar un proyecto basado en la democracia, la participación, la equidad y la solidaridad. Para ello, sin embargo, ha encontrado en los Estados una limitante. En el presente trabajo se realiza una aproximación al proceso de institucionalización y desarrollo de la agenda de la ESS en el marco del Mercado Común del Sur (MERCOSUR), para explorar de qué formas y con qué limites se introdujeron y sostuvieron discusiones vinculadas a un modelo -opuesto- de construcción económica y social. Para ello, se recurre a una metodología eminentemente cualitativa, siguiendo las estrategias propuestas por la teoría fundamentada en datos.A economia social e solidária nas políticas públicas regionais. O caso do MERCOSUL. Da década de 1990, os países da América Latina construíram novas ferra mentas comerciais com uns outros países voltados para os postulados do neoliberalismo. Esse processo caracterizou-se pelo ênfase na dimensão econômica e, ao mesmo tempo, pela perda da relevância nas dimensões política e social. Porém, essas instituições serem criadas com esses prin cípios norteadores, conseguiram ser construídas experiências ancoradas em princípios e valores da economia social e solidária (ESS). Com múltiplos empreendimentos, e tendo como unidade principal as cooperativas, esse modelo é reconhecido desde sua origem como uma proposta teórica e política que procura desenvolver um projeto com base na democracia, participação, equidade e solidariedade. No entanto, isso aconteceu nos Estados, mas com limitações. No presente trabalho, apresenta-se uma aproximação do processo de institucionalização e desenvolvimento da agenda da ESS, no quadro do Mercado Comum do Sul (MERCOSUL), para pesquisar de que forma e com que limites foram introduzidas as discussões vinculadas ao modelo contrário ao da economia social e solidária. Para isso, utiliza-se uma metodologia eminentemente qualitativa, seguindo estratégias da teoria fundamentada em dados.The social and solidarity economy in regional public policies. The case of MERCOSUR. Since the 1990s, Latin American countries have been building new commercial tools with third countries based on the postulates of neoliberalism. This process was characterized by the revalorization of the economic dimension accompanied by a loss of relevance of the political and social dimensions. However, experiences anchored in the principles and values of the social and solidarity economy (SSE) originated within the framework of institutions created with the guiding principles of that time. With multiple undertakings and with co-operatives as the main unit, this model has been recognized since its origin as a theoretical and political proposal that seeks to develop a project based on democracy, participation, equity and solidarity. However, in order to do so, it has encountered a limitation in the States. In this work, we approach the process of institutionalization and development of the SSE agenda within the framework of the Southern Common Market (MERCOSUR), in order to explore in what ways and with what limits discussions linked to a (opposing) model of economic and social construction were introdu ced and held. For this purpose, an eminently qualitative methodology is used, following the strategies proposed by the data-based theory.Centro de Investigación en Economía y ProspectivaFil: Gonzalez, Leticia. Centro de Estudios en Ciudadanía, Estado y Asuntos Políticos. Facultad de Ciencias Sociales. Universidad de Buenos AiresFil: Gonzalez, Leticia. Instituto Nacional de Tecnología Agropecuaria (INTA). Centro de Investigaciones en Economía y Prospectiva (CIEP); ArgentinaFil: Dubitzky, Diego Luis. Universidad de Buenos Aires. Facultad de Ciencias Sociales; Argentin

Cooperativity in binding processes: new insights from phenomenological modeling

Cooperative binding is one of the most interesting and not fully understood phenomena involved in control and regulation of biological processes. Here we analyze the simplest phenomenological model that can account for cooperativity (i.e. ligand binding to a macromolecule with two binding sites) by generating equilibrium binding isotherms from deterministically simulated binding time courses. We show that the Hill coefficients determined for cooperative binding, provide a good measure of the Gibbs free energy of interaction among binding sites, and that their values are independent of the free energy of association for empty sites. We also conclude that although negative cooperativity and different classes of binding sites cannot be distinguished at equilibrium, they can be kinetically differentiated. This feature highlights the usefulness of pre-equilibrium time-resolved strategies to explore binding models as a key complement of equilibrium experiments. Furthermore, our analysis shows that under conditions of strong negative cooperativity, the existence of some binding sites can be overlooked, and experiments at very high ligand concentrations can be a valuable tool to unmask such sites.Fil: Cattoni, Diego Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; Argentina. Universite Montpellier II; FranciaFil: Chara, Osvaldo. Universite Montpellier II; Francia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física de Líquidos y Sistemas Biológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física de Líquidos y Sistemas Biológicos; ArgentinaFil: Kaufman, Sergio Benjamín. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; ArgentinaFil: Gonzalez Flecha, Francisco Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; Argentin

The combination of geomatic approaches and operational modal analysis to improve calibration of finite element models: a case of study in Saint Torcato church (Guimarães, Portugal)

This paper present a set of procedures based on laser scanning, photogrammetry (Structure from Motion) and operational modal analysis in order to obtain accurate numeric models which allows identigying architectural complications that arise in historical buildings. In addition, themethod includes tools that facilitate building-damage monitoring tasks. All of these aimed to obtain robust basis for numerical analysis of the actual behavior and monitoring task. This case study seeks to validate said methodologies, using as an example the case of Saint Torcato Church, located in Guimãres, Portugal

Low X-ray Luminosity Galaxy Clusters. III: Weak Lensing Mass Determination at 0.18 << z << 0.70

This is the third of a series of papers of low X-ray luminosity galaxy clusters. In this work we present the weak lensing analysis of eight clusters, based on observations obtained with the Gemini Multi-Object Spectrograph in the $g'$, $r'$ and $i'$ passbands. For this purpose, we have developed a pipeline for the lensing analysis of ground-based images and we have performed tests applied to simulated data. We have determined the masses of seven galaxy clusters, six of them measured for the first time. For the four clusters with availably spectroscopic data, we find a general agreement between the velocity dispersions obtained via weak lensing assuming a Singular Isothermal Sphere profile, and those obtained from the redshift distribution of member galaxies. The correlation between our weak lensing mass determinations and the X-ray luminosities are suitably fitted by other observations of the $M-L_{X}$ relation and models

Optimization of the Loading of an Environmentally Friendly Compatibilizer Derived from Linseed Oil in Poly(Lactic Acid)/Diatomaceous Earth Composites

[EN] Maleinized linseed oil (MLO) has been successfully used as biobased compatibilizer in polyester blends. Its effciency as compatibilizer in polymer composites with organic and inorganic fillers, compared to other traditional fillers, has also been proved. The goal of this work is to optimize the amount of MLO on poly(lactic acid)/diatomaceous earth (PLA/DE) composites to open new potential to these materials in the active packaging industry without compromising the environmental effciency of these composites. The amount of DE remains constant at 10 wt% and MLO varies from 1 to 15 phr (weight parts of MLO per 100 g of PLA/DE composite). The e ect of MLO on mechanical, thermal, thermomechanical and morphological properties is described in this work. The obtained results show a clear embrittlement of the uncompatibilized PLA/DE composites, which is progressively reduced by the addition of MLO. MLO shows good miscibility at low concentrations (lower than 5 phr) while above 5 phr, a clear phase separation phenomenon can be detected, with the formation of rounded microvoids and shapes which have a positive e ect on impact strength.This research was funded by the Ministry of Science, Innovation, and Universities (MICIU) project number MAT2017-84909-C2-2-R. L. Quiles-Carrillo is recipient of a FPU grant (FPU15/03812) from the Spanish Ministry of Education, Culture, and Sports (MECD). D. Lascano acknowledges UPV for the grant received though the PAID-01-18 program. N. Montanes acknowledges the project "Development and production of new material from revalued industrial wastes for technological sector applications" for partially funding this research.Gonzalez, L.; Agüero, Á.; Quiles-Carrillo, L.; Lascano-Aimacaña, DS.; Montanes, N. (2019). Optimization of the Loading of an Environmentally Friendly Compatibilizer Derived from Linseed Oil in Poly(Lactic Acid)/Diatomaceous Earth Composites. Materials. 12(10):1-15. https://doi.org/10.3390/ma12101627S115121