Genotypic Diversity among Brevibacillus laterosporus Strains

In comparison with other entomopathogenic Bacillus species, the genome of Brevibacillus laterosporus is poorly characterized. The aim of this study was to examine genetic variability in B. laterosporus by using a range of typing methodologies. Strains of B. laterosporus were examined for variation in 13 chromosomal genes encoding enzymes by multilocus enzyme electrophoresis. Optimal conditions of pulsed-field gel electrophoresis and randomly amplified polymorphic DNA were established that allowed analysis of the genome of B. laterosporus. None of these techniques allowed the identification of a convenient molecular marker for entomopathogenic strains, although one specific primer amplified only DNA from almost all mosquitocidal strains.     

WOX14 promotes bioactive gibberellin synthesis and vascular cell differentiation in Arabidopsis

Procambial and cambial stem cells provide the initial cells that allow the formation of vascular tissues. WOX4 and WOX14 have been shown to act redundantly to promote procambial cell proliferation and differentiation. Gibberellins (GAs), which have an important role in wood formation, also stimulate cambial cell division. Here we show that the loss of WOX14 function phenocopies some traits of GA‐deficient mutants that can be complemented by exogenous GA application, whereas WOX14 overexpression stimulates the expression of GA3ox anabolism genes and represses GA2ox catabolism genes, promoting the accumulation of bioactive GA. More importantly, our data clearly indicate that WOX14 but not WOX4 promotes vascular cell differentiation and lignification in inflorescence stems of Arabidopsis.     

Production and purification of an untagged recombinant pneumococcal surface protein A (PspA4Pro) with high-purity and low endotoxin content

Applied Microbiology and Biotechnology - Streptococcus pneumoniae is the main cause of pneumonia, meningitis, and other conditions that kill thousands of children every year worldwide. The...     

Phylogeography of the southern skua complex-rapid colonization of the southern hemisphere during a glacial period and reticulate evolution

Whilst we have now a good understanding how past glaciation influenced species at the northern hemisphere, our knowledge of patterns and modes of speciation is far more limited for the southern hemisphere. We provide mtDNA based data on the phylogeography of a circumpolar distributed southern hemisphere seabird group-the southern skua complex (Catharacta spp.). Diversification of southern skuas dates between 210,000 yBP and 150,000 yBP and coincides with a glacial spanning 230,000-140,000 yBP. Skuas most likely first inhabited the Antarctic continent, in the course of global cooling and increasing glaciation spread to the sub-antarctic islands and Tristan da Cunha and finally colonized Patagonia and the Falkland Islands at the glacial maximum. Despite significant differences between taxa most populations still exchange genes with neighboring populations of other taxa and speciation is incomplete.     

Human erythrocyte hemolysis induced by selenium and tellurium compounds increased by GSH or glucose: a possible involvement of reactive oxygen species

Oxidative stress can induce complex alterations of membrane proteins in red blood cells (RBCs) eventually leading to hemolysis. RBCs represent a good model to investigate the damage induced by oxidizing agents. Literature data have reported that chalcogen compounds can present pro-oxidant properties with potent inhibitory effects on cell growth, causing tissue damage and inhibit a variety of enzymes. In this study, human erythrocytes were incubated in vitro with various chalcogen compounds at 37 °C: diphenyl ditelluride (1), dinaphthalen diteluride (2), diphenyl diselenide (3), (S)-tert-butyl 1-diselenide-3-methylbutan-2-ylcarbamate (4), (S)-tert-butyl 1-diselenide-3-phenylpropan-2-ylcarbamate (5), selenium dioxide (6) and sodium selenite (7) in order to investigate their potential in vitro toxicity. After 6 h of incubation, all the tested compounds increased the hemolysis rate, when compared to control and compound (2) had the most potent hemolytic effect. The addition of reduced glutathione (GSH) or glucose to the incubation medium enhanced hemolysis caused by chalcogen compounds. The thiol oxidase activity of these compounds was evaluated by measuring the rate of cysteine (CYS) and dithiotreitol (DTT) oxidation. DTT and cysteine oxidation was increased by all the compounds tested. The results suggest a relationship between the oxidation of intracellular GSH and subsequent generation of free radicals with the hemolysis by chalcogen compounds.