Multiple Phosphorylation Sites and Quaternary Organization of Guanine-Nucleotide Exchange Complex of Elongation Factor-1 (EF-1βγδ/ValRS) Control the Various Functions of EF-1α

The eukaryotic guanine-nucleotide exchange factor commonly called elongation factor-1 (EF-1), comprises four different subunits including valyl-tRNA synthetase (EF-1/ValRS). The factor is multiply-phosphorylated by three different protein kinases, protein kinase C, casein kinase II and cyclin dependent kinase 1 (CDK1). EF-1/ValRS is organized as a macromolecular complex for which we propose a new structural model. Evidence that EF-1/ValRS is a sophisticated supramolecular complex containing many phosphorylation sites, makes it a potential regulator of any of the functions of its partner EF-1, not only involved in protein synthesis elongation, but also in many other cellular functions.     

Comparison of different methods of estimating the mean radiant temperature in outdoor thermal comfort studies

Correlations between outdoor thermal indices and the calculated or measured mean radiant temperature T_mrt are in general of high importance because of the combined effect on human energy balance in outdoor spaces. The most accurate way to determine T_mrt is by means of integral radiation measurements, i.e. measuring the short- and long-wave radiation from six directions using pyranometers and pyrgeometers, an expensive and not always an easily available procedure. Some studies use globe thermometers combined with air temperature and wind speed sensors. An alternative way to determine T_mrt is based on output from the RayMan model from measured data of incoming global radiation and morphological features of the monitoring site in particular sky view factor (SVF) data. The purpose of this paper is to compare different methods to assess the mean radiant temperature T_mrt in terms of differences to a reference condition (T_mrt calculated from field measurements) and to resulting outdoor comfort levels expressed as PET and UTCI values. The T_mrt obtained from field measurements is a combination of air temperature, wind speed and globe temperature data according to the forced ventilation formula of ISO 7726 for data collected in Glasgow, UK. Four different methods were used in the RayMan model for T_mrt calculations: input data consisting exclusively of data measured at urban sites; urban data excluding solar radiation, estimated SVF data and solar radiation data measured at a rural site; urban data excluding solar radiation with SVF data for each site; urban data excluding solar radiation and including solar radiation at the rural site taking no account of SVF information. Results show that all methods overestimate T_mrt when compared to ISO calculations. Correlations were found to be significant for the first method and lower for the other three. Results in terms of comfort (PET, UTCI) suggest that reasonable estimates could be made based on global radiation data measured at the urban site or as a surrogate of missing SR data or globe temperature data recorded at the urban area on global radiation data measured at a rural location.     

Localization of thymostimulin in mammalian thymuses: comparative evaluation

An anti-thymostimulin (TS) serum was tested on rabbit, guinea-pig, lamb and pig thymuses to study the localization of the hormonal factor. The immuno-peroxidase method, with some modifications, was applied to tissue fixed in Bouin's or in Bouin-PAF liquids and embedded in paraffin wax. Immuno-reactivity was shown in reticulo-epithelial cells in the cortex, in the medulla and in the external cells of the Hassall's corpuscles. The intensity of the immuno-reaction is stronger in pig thymus, whereas in lamb, rabbit and guinea-pig thymuses it is more uniform and pale, but to varying degrees. Comparison with the localization of TS in thymuses of other mammals and man and the problem of species-specificity were discussed.     

Characterization and biotechnological application of an acid alpha-galactosidase from Tachigali multijuga Benth. seeds

Tachigali multijuga Benth. seeds were found to contain protein (364 mg g(-1)dwt), lipids (24 mg g(-1)dwt), ash (35 mg g(-1)dwt), and carbohydrates (577 mg g(-1)dwt). Sucrose, raffinose, and stachyose concentrations were 8.3, 3.0, and 11.6 mg g(-1)dwt, respectively. alpha-Galactosidase activity increased during seed germination and reached a maximum level at 108 h after seed imbibition. The alpha-galactosidase purified from germinating seeds had an M(r) of 38,000 and maximal activity at pH 5.0-5.5 and 50 degrees C. The enzyme was stable at 35 degrees C and 40 degrees C, but lost 79% of its activity after 30 min at 50 degrees C. The activation energy (E(a)) values for p-nitrophenyl-alpha-d-galactopyranoside (pNPGal) and raffinose were 13.86 and 4.75 kcal mol(-1), respectively. The K(m) values for pNPGal, melibiose, raffinose, and stachyose were 0.45, 5.37, 39.62 and 48.80 mM, respectively. The enzyme was sensitive to inhibition by HgCl(2), SDS, AgNO(3), CuSO(4), and melibiose. d-Galactose was a competitive inhibitor (K(i)=2.74 mM). In addition to its ability to hydrolyze raffinose and stachyose, the enzyme also hydrolyzed galactomannan.     

Occurrence of deoxynivalenol and zearalenone in brewing barley grains from Brazil

Barley (Hordeum vulgare L.) is an important cereal crop for food and represents one of the main ingredients in beer production. Considering the importance of barley and its derived products, the knowledge about the mycotoxin contamination in the barley production is essential in order to assess its safety. In this study, the levels of deoxynivalenol (DON) and zearalenone (ZEN) in brewing barley were determined using a LC-MS/MS method. A survey was conducted in 2015 to estimate the mycotoxin levels in these products (n?=?76) from four crop regions in Brazil. The results showed high levels of DON and ZEN in the analyzed samples, with contamination levels of 94 and 73.6%, respectively. The mean levels of DON and ZEN ranged from 1700 to 7500 μg/kg and from 300 to 630 μg/kg, respectively. Barley samples from regions 1 and 2 presented higher levels of ZEN and DON, respectively, and those from region 4 presented lower levels of both. Co-occurrence of DON and ZEN was seen in the majority of the barley grain samples, and the mycotoxin content was above the maximum levels established by the Brazilian and European regulations.     

Mutational analysis of human T-cell leukemia virus type 2 Tax.

A mutational analysis of human T-cell leukemia virus type 2 (HTLV-2) Tax (Tax-2) was performed to identify regions within Tax-2 important for activation of promoters through the CREB/ATF or NF-kappaB/Rel signaling pathway. Tax-2 mutations within the putative zinc-binding region as well as mutations at the carboxy terminus disrupted CREB/ATF transactivation. A single mutation within the central proline-rich region of Tax-2 disrupted the transactivation of the NF-kappaB/Rel pathway. Surprisingly, this mutation, which is thought to be in a separate activation domain, was suppressed by mutations within or around the putative zinc-binding region, suggesting an interaction between these two regions. These analyses indicate that the functional regions or domains important for transactivation through the CREB/ATF or NF-kappaB/Rel signaling pathway are similar, but not identical, in Tax-1 and Tax-2. Identification of these distinct Tax-2 mutants should facilitate comparative biological studies of HTLV-1 and HTLV-2 and ultimately lead to the determination of the functional importance of Tax trans-acting capacities in T-lymphocyte transformation by HTLV.     

Conventional and transgenic strategies to enhance the acid soil tolerance of barley

The aluminum (Al³⁺) tolerance of barley cultivars predominately from Brazil was compared to that of cultivars from other countries, wild barley accessions, and a transgenic line (L5) over-expressing TaALMT1, the major Al³⁺ tolerance gene from wheat. After screening conventional germplasm for Al³⁺ tolerance in hydroponics, 18 genotypes were further characterized in a short-term soil experiment. Among the Brazilian cultivars, Antarctica 01 and BRS Mariana showed the greatest relative root length (RRL) in acid soil. However, these cultivars were significantly less tolerant than the foreign cultivars Dayton (USA) and Murasakimochi (Japan) and the transgenic line L5 which out-performed all conventional genotypes. In long-term growth trials, the transgenic line produced the greatest relative root and relative shoot dry weight. Relative grain yield was greatest in the transgenic line and Dayton. All genotypes were also scored for two genetic markers linked to HvAACT1, the major Al³⁺ tolerance gene in barley. One marker detects a 1-kb insertion in the promoter that increases gene expression and leads to increased Al³⁺-activated citrate efflux from root apices. The other marker detects a 21-bp indel downstream of the coding region. The 1-kb insertion was only detected in Dayton and Murasakimochi that were the best performing cultivars among the non-transgenic germplasm. Interestingly, the Brazilian cultivars with an intermediate level of tolerance, Antarctica 01 and BRS Mariana, lacked the 1-kb insertion but had enhanced HvAACT1 expression compared to an Al³⁺-sensitive cultivar. No clear correlation was observed between Al³⁺ tolerance and the 21-bp indel marker in the short-term soil trials. We conclude that improved Al³⁺ tolerance in barley could be achieved by combining the best allele of HvAACT1 along with TaALMT1 as a transgene.