EARLY STARVATION1 specifically affects the phosphorylation action of starch‐related dikinases

Starch phosphorylation by starch‐related dikinases glucan, water dikinase (GWD) and phosphoglucan, water dikinase (PWD) is a key step in starch degradation. Little information is known about the precise structure of the glucan substrate utilized by the dikinases and about the mechanisms by which these structures may be influenced. A 50‐kDa starch‐binding protein named EARLY STARVATION1 (ESV1) was analyzed regarding its impact on starch phosphorylation. In various in vitro assays, the influences of the recombinant protein ESV1 on the actions of GWD and PWD on the surfaces of native starch granules were analyzed. In addition, we included starches from various sources as well as truncated forms of GWD. ESV1 preferentially binds to highly ordered, α‐glucans, such as starch and crystalline maltodextrins. Furthermore, ESV1 specifically influences the action of GWD and PWD at the starch granule surface. Starch phosphorylation by GWD is decreased in the presence of ESV1, whereas the action of PWD increases in the presence of ESV1. The unique alterations observed in starch phosphorylation by the two dikinases are discussed in regard to altered glucan structures at the starch granule surface.     

Methyl jasmonate effects on volatile oil compounds and antioxidant activity of leaf extract of two basil cultivars under salinity stress

Basil (Ocimum basilicum L.) as an economic and culinary herb is used in traditional medicine. In this research, a pot experiment was conducted, as factorial based on randomized completely design with three replications, to examine the influence of methyl jasmonate (MeJA) on volatile substances and chemical components as well as antioxidant activity of leaf’s extract from two commercial cultivars (Genove and Rubi) of sweet basil under salinity stress. The treatments were comprised MeJA (0 and 0.5 mM) and salinity stresses (0, 30, 60, and 90 mM). Using MeJA foliarly meaningfully raised the essential oil content in the Rubi cultivar at 0 and 30 mM of salinity and in the Genove cultivar just on 30 mM of salinity. MeJA treatment increased the essential oil content and also showed noticeable effects on the main components of the oils. The foliar application of MeJA raised the percentages of linalool and 1,8-cineole, whereas reduced the percentages of α-cadinol, α-bergamotene, β-maaliene, and eugenol in the extracted oil. In both basil cultivars, the MeJA significantly enhanced the antioxidant activity. The highest antioxidant activities in the Rubi and Genove cultivars were obtained at 0 mM (control) and 60 mM of salinity with the MeJA application, respectively. In conclusion, the foliar application of MeJA caused to different responses in the cultivars and reduced the negative effects of salt stress.     

Modulation of recombination and DNA repair by the RecG and PriA helicases of Escherichia coli K-12.

The RecG protein of Escherichia coli is a structure-specific DNA helicase that targets strand exchange intermediates in genetic recombination and drives their branch migration along the DNA. Strains carrying null mutations in recG show reduced recombination and DNA repair. Suppressors of this phenotype, called srgA, were located close to metB and shown to be alleles of priA. Suppression depends on the RecA, RecBCD, RecF, RuvAB, and RuvC recombination proteins. Nine srgA mutations were sequenced and shown to specify mutant PriA proteins with single amino acid substitutions located in or close to one of the conserved helicase motifs. The mutant proteins retain the ability to catalyze primosome assembly, as judged by the viability of recG srgA and srgA strains and their ability to support replication of plasmids based on the ColE1 replicon. Multicopy priA+ plasmids increase substantially the recombination- and repair-deficient phenotype of recG strains and confer similar phenotypes on recG srgA double mutants but not on ruvAB or wild-type strains. The multicopy effect is eliminated by K230R, C446G, and C477G substitutions in PriA. It is concluded that the 3'-5' DNA helicase/translocase activity of PriA inhibits recombination and that this effect is normally countered by RecG.     

DNA binding and helicase domains of the Escherichia coli recombination protein RecG.

The Escherichia coli RecG protein is a unique junction-specific helicase involved in DNA repair and recombination. The C-terminus of RecG contains motifs conserved throughout a wide range of DNA and RNA helicases and it is thought that this C-terminal half of RecG contains the helicase active site. However, the regions of RecG which confer junction DNA specificity are unknown. To begin to assign structure-function relationships within RecG, a series of N- and C-terminal deletions have been engineered into the protein, together with an N-terminal histidine tag fusion peptide for purification purposes. Junction DNA binding, unwinding and ATP hydrolysis were disrupted by mutagenesis of the N-terminus. In contrast, C-terminal deletions moderately reduced junction DNA binding but almost abolished unwinding. These data suggest that the C-terminus does contain the helicase active site whereas the N-terminus confers junction DNA specificity.     

TB trifusion antigen adsorbed on calcium phosphate nanoparticles stimulates strong cellular immunity in mice

Among various vaccine candidates, subunit vaccines play an important role in immune protection against tuberculosis (TB). Calcium phosphate (CP) is considered as a strong inorganic adjuvant due to its great potential in increasing immune responses. The purpose of this study was to evaluate specific immune responses following the administration of trifusion-CP nanoparticles. The physiochemical properties of these nanoparticles, including morphology, particle size, zeta potential and adsorption rate, were measured in vitro. Subcutaneous immunization was performed three times on days 0, 14, and 28. Two weeks after the last administration, IFN-gamma, IL-4, and TGF-beta levels were measured by indirect enzyme linked immunosorbent assay (ELISA). The trifusion protein was successfully adsorbed onto calcium phosphate nanoparticles. The mean sizes of the resultant trifusion- CPN and CPN were 97.84 ± 12.08 and 67 ± 11.85 nm, respectively. CPN containing trifusion had stronger ability to induce IFN-gamma than the control groups. IL-4 and TGF-beta secretions in trifusion and trifusion-CPN groups were higher than those in the PBS group. However, there was no significant (p > 0.05) difference in IL-4 and TGFbeta concentrations between trifusion group and trifusion- CPN group. Therefore, calcium phosphate nanoparticles are good candidates for immunization against TB because antigen can be easily adsorbed onto CPN and strong cellular immune responses against CPN-antigen can be stimulated.     

Identification and Characterization of two new Fungal Pathogens of Polygonatum odoratum (Angular Solomon's seal) in Italy

Polygonatum odoratum (Mill.) Druce (Angular Solomon's seal) is a well‐known ornamental plant and herbal drug, which is used in traditional medicine. Severe leaf spots were observed in wild Angular Solomon's seal plants in a public park in Trento, Italy. A combination of morphological and molecular characteristics, including sequence data of ITS‐rDNA, large subunit (LSU), beta tubulin (TUB) and glyceraldehyde 3‐phosphate dehydrogenase (GAPDH) led to identification of two species, namely Phoma odoratissimi and Colletotrichum dematium s. str., isolated from these leaf spots. Pathogenicity of the isolates was confirmed on wounded leaves of Po. odoratum; indeed, both species induced leaf spot symptoms on inoculated leaves within 10 days of inoculation. This is the first report of leaf spot disease caused by Ph. odoratissimi and C. dematium s. str. on Po. odoratum, which can be considered a new host for both the species examined in this study. In addition, isolation of Ph. odoratissimi represents a new record for the mycobiota of Italy.     

Development of a novel engineered antibody targeting human CD123

Antibody engineering involves a range of custom modifications of immunoglobulins to improve their affinity, valency, and pharmacokinetics, ensuring a better target therapy achievement. A number of therapeutic antibodies have been used for cell surface receptor blockage, interfering with the ligand binding and inhibiting receptor-driven activation of cells. Here we describe the construction and characterization of a recombinant bivalent single-chain Fv (biscFv) that targets CD123. On conversion of anti-CD123 scFv to biscFv format, the recognition of the cognate ligand is not altered. Moreover, the increased overall efficacy of the anti-CD123 biscFv in binding and inhibition of CD123/IL-3 (interleukin-3) interactions in TF-1 cells is demonstrated.     

Tissue composition effect on dose distribution in neutron brachytherapy/neutron capture therapy

Aim

The aim of this study is to assess the effect of the compositions of various soft tissues and tissue-equivalent materials on dose distribution in neutron brachytherapy/neutron capture therapy.

Background

Neutron brachytherapy and neutron capture therapy are two common radiotherapy modalities.

Materials and methods

Dose distributions were calculated around a low dose rate ²⁵²Cf source located in a spherical phantom with radius of 20.0 cm using the MCNPX code for seven soft tissues and three tissue-equivalent materials. Relative total dose rate, relative neutron dose rate, total dose rate, and neutron dose rate were calculated for each material. These values were determined at various radial distances ranging from 0.3 to 15.0 cm from the source.

Results

Among the soft tissues and tissue-equivalent materials studied, adipose tissue and plexiglass demonstrated the greatest differences for total dose rate compared to 9-component soft tissue. The difference in dose rate with respect to 9-component soft tissue varied with compositions of the materials and the radial distance from the source. Furthermore, the total dose rate in water was different from that in 9-component soft tissue.

Conclusion

Taking the same composition for various soft tissues and tissue-equivalent media can lead to error in treatment planning in neutron brachytherapy/neutron capture therapy. Since the International Commission on Radiation Units and Measurements (ICRU) recommends that the total dosimetric uncertainty in dose delivery in radiotherapy should be within ±5%, the compositions of various soft tissues and tissue-equivalent materials should be considered in dose calculation and treatment planning in neutron brachytherapy/neutron capture therapy.     

Determining the most effective traits to improve saffron (<Emphasis Type="Italic">Crocus sativus</Emphasis> L.) yield

To determine the effective traits to improve saffron yield, a split plot design based on RBCD was done in Mashhad region in Iran for three years (2012–2014). The results showed that all traits except number of daughter corm, fresh weight of daughter corm and dry leaf weight had low general heritability. Results of genotypic and phenotypic coefficients of variation and genetic advance demonstrated that the majority of traits had a low diversity and the selection did not have any effect in improving the traits. As a result, the best way to increase saffron yield is improvement of farm management. It was also found that saffron yield had the highest phenotypic and genotypic correlations with fresh and dry weight of daughter corm and dry and fresh flower weight. Therefore, the efforts to improve these traits will increase saffron yield. According to the present study 5-Jun to 5-Jul was found to be the best sowing date for planting saffron. Also, the Mashhad and Torbat ecotypes were the best ecotypes in this study. Phenotypic and genotypic path analysis showed that in the first step three traits number of daughter corm, fresh flower weight and flower number and in the second step traits fresh weight of daughter corm, dry flower weight and dry leaf weight interred to the regression model and had the highest positive direct and indirect effects on saffron yield. Mainly, it can be derived that the implementation of correct farm management including appropriate sowing date, saffron ecotypes, proper density, bigger and higher quality saffron corm can play an important role in improving yield components and subsequently increasing saffron yield.