Substrate type and CO2 addition significantly influence succinic acid production of Basfia succiniciproducens.

Metabolic engineering has shown that optimizing metabolic pathways' fluxes for industrial purposes requires a methodical approach. Accordingly, in this study, in silico metabolic modeling was utilized to characterize the lesser-known strain Basfia succiniciproducens under different environmental conditions, followed by the use of industrially relevant substrates for succinic acid synthesis. Based on RT-qPCR carried out in flask experiments, we discovered a relatively large difference in the expression levels of ldhA gene compared to glucose in both xylose and glycerol cultures. In bioreactor-scale fermentations, the impact of different gas phases (CO2, CO2/AIR) on biomass yield, substrate consumption, and metabolite profiles was also investigated. In the case of glycerol, the addition of CO2 increased biomass as well as target product formation, while using CO2/AIR gas phase resulted in higher target product yield (0.184 mM⋅mM-1). In case of xylose, using CO2 alone would result in higher succinic acid production (0.277 mM⋅mM-1). The promising rumen bacteria, B. succiniciproducens, has shown to be suitable for succinic acid production from both xylose and glycerol. As a result, our findings present new opportunities for broadening the range of raw materials used in this significant biochemical process. Our study also sheds light on fermentation parameter optimization for this strain, namely that, CO2/AIR supply has a positive effect on target product formation.

Position-based anthropometric characteristics and general physiological performance of national level, U18 ice hockey players / Características antropométricas basadas en la posición y el rendimiento fisiológico general de jugadores de hockey sobre hielo de nivel nacional, sub-18

Identifying talented players requires subjective, as well as objective assessments of playing ability and performance. The assessment of anthropometric characteristics, as well as general physiological performance can be used for player selection. The primary purpose of this study was to determine whether positional profiling is possible for national level ice hockey players by examining anthropometric characteristics and physiological performance. The study involved two ice-hockey teams, U18 and U23, in total of 49 athletes (32 forwards and 17 defensemen), members of the “Székelyföldi” Ice Hockey Academy (SZJA). Data collection was conducted in May 2020, at the SZJAs Medical and Methodological Center. Body height was determined including barefoot height (± 0.1 cm) using a wall mounted stadiometer. Body weight was measured with a standard scale. A standard incremental maximal oxygen uptake test was conducted in the laboratory by means of open-circuit spirometry and computerized instrumentation (CPET Cosmed, Italy) following the Bruce protocol. With the use of the descriptive statistics, we found no differences at the anthropometric characteristics between forwards and defensemen. Regarding the physiological characteristics, some possible differences were found for maximal- and absolute oxygen uptake rate. While our results from descriptive statistics show no significant differences between the two studied ice hockey position, based on the Mann-Whitney U test, considering all parameter values, we found that there were significant differences between the two groups within this sample number. (AU)

La identificación de jugadores talentosos requiere evaluaciones subjetivas y objetivas de la capacidad y el rendimiento de juego. La evaluación de las características antropométricas, así como el rendimiento fisiológico general, pueden utilizarse para la selección de jugadores. El objetivo principal de este estudio fue determinar si el perfil posicional es posible para los jugadores de hockey sobre hielo de nivel nacional mediante el examen de las características antropométricas y el rendimiento fisiológico. El estudio involucró a dos equipos de hockey sobre hielo, U18 y U23, en un total de 49 atletas (32 delanteros y 17 defensas), miembros de la Academia de Hockey sobre Hielo "Székelyföldi" (SZJA). La recolección de datos se realizó en mayo de 2020, en el Centro Médico y Metodológico SZJAS. La altura del cuerpo se determinó incluyendo la altura de los pies descalzos (±0,1 cm) utilizando un estadiómetro montado en la pared. El peso corporal se midió con una balanza estándar. Se realizó una prueba de consumo de oxígeno máximo incremental estándar en el laboratorio mediante espirometría de circuito abierto e instrumentación computarizada (CPET Cosmed, Italia) siguiendo el protocolo de Bruce. Con el uso de la estadística descriptiva, no encontramos diferencias en las características antropométricas entre delanteros y defensas. En cuanto a las características fisiológicas, se encontraron algunas posibles diferencias para la tasa de consumo de oxígeno máxima y absoluta. Si bien nuestros resultados de las estadísticas descriptivas no muestran diferencias significativas entre las dos posiciones de hockey sobre hielo estudiadas, con base en la prueba U de Mann-Whitney, considerando todos los valores de los parámetros, encontramos que hubo diferencias significativas entre los dos grupos dentro de este número de muestra. (AU)

Role of Lacosamide in Preventing Pentylenetetrazole Kindling-Induced Alterations in the Expression of the Gamma-2 Subunit of the GABAA Receptor in Rats.

BACKGROUND: Epilepsy remains challenging to treat still no etiologic treatment has been identified, however, some antiepileptic drugs (AEDs) are able to modify the pathogenesis of the disease. Lacosamide (LCM) has been shown to possess complex anticonvulsant and neuroprotective actions, being an enhancer of the slow inactivation of voltage-gated sodium channels, and it has the potential to prevent epileptogenesis. Recent evidence has shown that LCM indirectly improves the function of GABAA receptors. Receptors at most GABAergic synapses involve the gamma-2 subunit, which contributes to both phasic and tonic inhibition, and its presence assures benzodiazepine sensitivity. Moreover, mutant gamma-2 subunits were associated with generalized epilepsy syndromes. In animal models, the expression of the gamma-2 subunit of the gamma-aminobutyric acid A receptor (GABAAg2) was shown to be increased in pentylenetetrazole (PTZ)-induced chemical kindling in Wistar rats. OBJECTIVE: This study hypothesized that LCM might affect the kindling process by influencing the expression of GABAA receptors in the hippocampus. METHODS: The gene and protein expression levels of the GABAAg2 were studied using RT-qPCR and immunofluorescent staining. RESULTS: It was found that LCM treatment (10 mg/kg i.p. daily for 57 days) reduced the maximal intensity of the PTZ-induced seizures but did not prevent kindling. On the other hand, LCM treatment reverted the increase of mRNA expression of GABAAg2 in the hippocampus and prevented the decrease of GABAAg2 protein in the hippocampal CA1 region. CONCLUSION: LCM could exhibit modulatory effects on the GABAergic system of the hippocampus that may be independent of the anticonvulsant action.

Influence of peat fires on the rainwater chemistry in intra-mountain basins with specific atmospheric circulations (Eastern Carpathians, Romania).

A comprehensive study on the chemical composition of precipitation, the influence of peat fires and their relations with atmospheric circulation was conducted in the year of 2012, in two intra-mountain basins, the Ciuc basin (CB) and the Giurgeu basin (GB), Eastern Carpathians, Romania. Atmospheric circulation types showed the presence of a westerly anticyclonic circulation, characterized by a strong development of the Azores High to the northern Atlantic, contributing to the appearance of peat-fires. Using ROCADA daily gridded climatic datasets, the maximum and minimum daily temperatures were extracted, showing deviation from 2 °C to 6 °C in the studied year against the multiannual mean for the 1981-2016 period. Rainwater samples were analyzed for pH, major anions and cations; HCO3- concentrations were calculated based on the empirical relationship between pH and HCO3-. The results showed that 45.16% and 54.55% of precipitation had pH > 7.0 at CB and GB, respectively. NH3, NH4+ and Ca2+ are the main neutralizing agents. The significant correlation between SO42- and NH4+ (r = 0.711 - CB; r = 0.736 - GB) indicated neutralization by NH3 in the forms of (NH4)2SO4 and NH4HSO4. Positive regression coefficient between the sum of (H+ + [NH4+] + [Ca2+]) and the sum of ([nss - SO42-] + [NO3-]) (r = 0.855 - CB; r = 0.796 - GB), showed that acid neutralization was primarily brought by NH4+ and/or CaCO3. Using Na as an indicator of marine origin, the proportions of sea salt and non-sea-salt were estimated from elemental ratios. According to correlation analysis and PCA, main acidic ions (SO42- and NO3-) and NH4+ were mainly derived from anthropogenic activities (biomass burning, peat fires, fertilization), while Ca2+ and Mg2+ originated from terrestrial sources. The behavior of gaseous pollutants and smoke distribution resulted from peat fires were deciphered using the HYSPLIT model in a case study.

In silico and in vivo stability analysis of a heterologous biosynthetic pathway for 1,4-butanediol production in metabolically engineered E. coli.

Recently, several approaches have been published in order to develop a functional biosynthesis route for the non-natural compound 1,4-butanediol (BDO) in E. coli using glucose as a sole carbon source or starting from xylose. Among these studies, there was reported as high as 18 g/L product concentration achieved by industrial strains, however BDO production varies greatly in case of the reviewed studies. Our motivation was to build a simple heterologous pathway for this compound in E. coli and to design an appropriate cellular chassis based on a systemic biology approach, using constraint-based flux balance analysis and bi-level optimization for gene knock-out prediction. Thus, the present study reports, at the "proof-of concept" level, our findings related to model-driven development of a metabolically engineered E. coli strain lacking key genes for ethanol, lactate and formate production (ΔpflB, ΔldhA and ΔadhE), with a three-step biosynthetic pathway. We found this strain to produce a limited quantity of 1,4-BDO (.89 mg/L BDO under microaerobic conditions and .82 mg/L under anaerobic conditions). Using glycerol as carbon source, an approach, which to our knowledge has not been tackled before, our results suggest that further metabolic optimization is needed (gene-introductions or knock-outs, promoter fine-tuning) to address the redox potential imbalance problem and to achieve development of an industrially sustainable strain. Our experimental data on culture conditions, growth dynamics and fermentation parameters can consist a base for ongoing research on gene expression profiles and genetic stability of such metabolically engineered E. coli strains.

A possible explanation of the germicide effect of carbon dioxide in supercritical state based on molecular-biological evidence.

Supercritical carbon dioxide (CO(2)) possesses germicide (bactericide and sporicide) effect. Despite of the fact, that this effect is used in industrial sterilization processes, the sterilization mechanism at molecular level is unclear. Our hypotheses can provide a molecular-biological explanation for the phenomenon. We believe that in supercritical state CO(2) reacts competitively with Met-tRNA(fMet), the formation rate and the amount of formyl-methionyl-tRNA (fMet-tRNA(fMet)) will be diminished by irreversible substrate consumption. The fMet-tRNA(fMet) possesses a key role in prokaryotic protein synthesis, being almost exclusively the initiator aminoacyl-tRNA. The formed carbamoyl-methionyl-tRNA (cMet-tRNA(fMet)), probably stable only under pressure and high CO(2) concentration, is stabilized by forming a ternary molecular complex with the GTP-form of the translational initiation factor 2 (GTP-IF2). This complex is unable to dissociate from preinitiation 70S ribosomal complex because of strong polar binding between the protein C-2 domain and the modified initiator aminoacyl-tRNA. The IF2-fMet-tRNA(fMet)-blocked 70S ribosomal preinitiation complex does not decompose following the GTP hydrolysis, becoming unable to synthesize proteins. The death of the microbial cell is caused by inhibition of the protein synthesis and energetic depletion. Moreover, we propose a possible mechanism for the accumulation of cMet-tRNA(fMet) in the bacterial cell. Since the translational process is an important target for antibiotics, the proposed mechanism could be a work hypothesis for discovery of new antibiotics. Made by high conservative character of prokaryotic translation initiation, the proposed IF2 pathway deterioration strategy may conduct to obtaining selective (with low mammalian toxicity) antimicrobials and at the same time, with reduced possibility of the drug resistance development.