Transcriptome-wide effect of DE-ETIOLATED1 (DET1) suppression in embryogenic callus of Carica papaya

Journal of Plant Research - Papaya is one of the most nutritional fruits, rich in vitamins, carotenoids, flavonoids and other antioxidants. Previous studies showed phytonutrient improvement without...     

Purification of a Bacteriocin-Like Inhibitory Substance Derived from Pediococcus acidilactici Kp10 by an Aqueous Micellar Two-Phase System

Aqueous micellar two-phase system (AMTPS) is an extractive technique of biomolecule, where it is based on the differential partitioning behavior of biomolecule between a micelle-rich and a micelle-poor phase. In this study, an AMTPS composed of a nonionic surfactant, Triton X-100 (TX-100) was used for purifying a bacteriocin-like inhibitory substance (BLIS) derived from Pediococcus acidilactici Kp10. The influences of the surfactant concentration and the effect of additives on the partitioning behavior and activity yield of the BLIS were investigated. The obtained coexistence curves showed that the mixtures of solutions composed of different surfactant concentrations (5–30% w/w) and 50% w/w crude load were able to separate into two phases at temperatures of above 60 °C. The optimum conditions for BLIS partitioning using the TX-100-based AMTPS were: TX-100 concentration of 22.5% w/w, CFCS load of 50% w/w, incubation time of 30 min at 75 °C, and back-extraction using acetone precipitation. This optimal partitioning resulted in an activity yield of 64.3% and a purification factor of 5.8. Moreover, the addition of several additives, such as sorbitol, KCl, dioctyl sulfosuccinate sodium salt, and Coomassie® Brilliant Blue, demonstrated no improvement in the BLIS separation, except for Amberlite® resin XAD-4, where the activity yield was improved to 70.3% but the purification factor was reduced to 2.3. Results from this study have demonstrated the potential and applicability of TX-100-based AMTPS as a primary recovery method for the BLIS from a complex fermentation broth of P. acidilactici Kp10. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2719, 2019     

A rapid and gentle method for the salt extraction of chromatin core histones H2A,H2B,H3 and H4 from rat liver nuclei

A complex of histones H2A, H2B, H3 and H4 has been isolated from purified rat liver nuclei by a method which is both gentle and rapid. Nuclei were homogenised in 0.25 M sucrose and the residual nuclear material obtained after centrifligation was adsorbed on calcium phosphate gel. After removing histone H1 from the adsorbed material by washing with 1M NaCl in 25 mM sodium phosphate buffer, pH 6.0, histones H2A, H2B, H3 and H4 were eluted together, with 2 M NaCl in 25 mM sodium phosphate buffer, pH 7.0. The core histones so obtained migrated as a single sharp band on polyacrylamide gel electrophoresis under non-denaturing conditions. Fractionation of the freshly prepared core histones on a Sephadex G-100 column yielded two major protein peaks. The peak having the larger elution volume contained histones H2A and H2B in equal amounts while the peak with the smaller elution volume contained all the four histones. Histones H3 and H4 were present in larger proportions in the second peak.     

Adenosine and ATP: mutually exclusive modifiers of the kinetics of ADP-induced aggregation of calf-platelets

Modulations of initial rate kinetics of ADP-induced aggregation of citrated calf platelet-rich plasma by adenosine and ATP were investigated employing a spectrophotometric platelet aggregation assay. The data were analysed according to the tenets of sequential shape-change and interaction model of aggregation. Adenosine and ATP increased the slopes and intercepts of double-reciprocal plots of ADP-aggregation kinetics. Examination of their slope and intercept effects together with their effects individually and in combination, on aggregation rates, suggested that adenosine and ATP acted at multiple, nonoverlapping, sites.     

Existence of sodium bicarbonate enhanced bioelectricity generation on Chlorella sp. biofilm in a Biophotovoltaic (BPV) system

Journal of Applied Phycology - Sodium bicarbonate (NaHCO3) is a low-cost inorganic carbon source, highly soluble in water and widely used in microalgae research. Using carbon dioxide (CO2) gas in...     

A fed-batch strategy to produce high poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-4-hydroxybutyrate) terpolymer yield with enhanced mechanical properties in bioreactor

Bioprocess and Biosystems Engineering - This study reports an efficient fed-batch strategy to improve poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-4-hydroxybutyrate) [P(3HB-co-3HV-co-4HB)]...     

Long-term corticosteroid treatment but not chronic stress affects 11β-hydroxysteroid dehydrogenase type I activity in rat brain and peripheral tissues

Long-term treatment (21 days) of male rats with corticosterone in the drinking water caused a significant increase in the activity of the NADP-dependent form of 11β-hydroxysteroid dehydrogenase (11-HSD1) in the pituitary, thymus, and spleen, (marginally in the hippocampus, amygdala and lymph nodes), without having any effect in a number of other central and peripheral tissues. In contrast, repeated restraint stress, although increasing plasma corticosterone to the same level as that observed after its administration, failed to change the activity of this key regulatory enzyme, which allows aldosterone to exert its specific effects in the presence of a large excess of corticosterone. This resistance to elevation in 11-HSD activity was also observed in the thymuses of subordinate rats during social stratification in a visible burrow system. In both cases, the circulating levels of corticosterone were much higher in stressed rats than in control animals. Factors which might account for these differences in response are discussed and compared with the situation in intact cells where, unlike in tissue homogenates, the reduction of 11-dehydrocorticosterone to corticosterone (reductase activity) appears to predominate.