Effect of dilution rate on eicosapentaenoic acid productivity ofPhaeodactylum tricornutum utex 640 in outdoor chemostat culture

Summary Eicosapentaenoic acid (EPA) volumetric productivity from an outdoor chemostat culture ofPhaeodactylum tricornutum UTEX 640 in a 50-l tubular photobioreactor varies with dilution rate, reaching a maximum of 47.8 mg l^–1 d^–1 at D=0.36 d^–1. Continuous culture at high dilution rates' is proposed as the most adequate operating mode to maximize polyunsaturated fatty acid production.     

The role of nutrition on epigenetic modifications and their implications on health

Nutrition plays a key role in many aspects of health and dietary imbalances are major determinants of chronic diseases including cardiovascular disease, obesity, diabetes and cancer. Adequate nutrition is particularly essential during critical periods in early life (both pre- and postnatal). In this regard, there is extensive epidemiologic and experimental data showing that early sub-optimal nutrition can have health consequences several decades later.     

A DNA Damage Checkpoint Pathway Coordinates the Division of Dikaryotic Cells in the Ink Cap Mushroom Coprinopsis cinerea

The fungal fruiting body or mushroom is a multicellular structure essential for sexual reproduction. It is composed of dikaryotic cells that contain one haploid nucleus from each mating partner sharing the same cytoplasm without undergoing nuclear fusion. In the mushroom, the pileus bears the hymenium, a layer of cells that includes the specialized basidia in which nuclear fusion, meiosis, and sporulation occur. Coprinopsis cinerea is a well-known model fungus used to study developmental processes associated with the formation of the fruiting body. Here we describe that knocking down the expression of Atr1 and Chk1, two kinases shown to be involved in the response to DNA damage in a number of eukaryotic organisms, dramatically impairs the ability to develop fruiting bodies in C. cinerea, as well as other developmental decisions such as sclerotia formation. These developmental defects correlated with the impairment in silenced strains to sustain an appropriated dikaryotic cell cycle. Dikaryotic cells in which chk1 or atr1 genes were silenced displayed a higher level of asynchronous mitosis and as a consequence aberrant cells carrying an unbalanced dose of nuclei. Since fruiting body initiation is dependent on the balanced mating-type regulator doses present in the dikaryon, we believe that the observed developmental defects were a consequence of the impaired cell cycle in the dikaryon. Our results suggest a connection between the DNA damage response cascade, cell cycle regulation, and developmental processes in this fungus.     

Effect of the phase state of lipids on their interaction with cobra cytotoxin

Interaction between cytotoxin of the Central Asia cobra venom and dimiristoylphosphatidylcholine bilayer depending on its phase state was studied by ESR with spin label. A conclusion can be drawn that the efficiency of cytotoxin effect on the membranes depends on their phase state. Cytotoxin molecules are incorporated into myophile region of the bilayer, only if the latter is in the liquid crystal state. The interaction between cytotoxins and lipids of the bilayer in a gel state is in the main conditioned by electrostatic forces.     

Acrylonitrile inhalation in rats: II. Excretion of thioethers and thiocyanate in urine

In male Wistar rats, the inhalation exposure to acrylonitrile (AN), 271 mg X m-3, 8 hours a day, 5 days a week, did not affect protein sulfhydryl concentration in liver and blood and decreased glutathione concentration in the liver, but not in the brain at the end of the fifth exposure. The urinary excretion of the main AN metabolites, thioethers (AN-mercapturic acids) and thiocyanate was proportional to the inhaled AN concentration (57, 125, 271 mg X m-3, respectively) in a single exposure for 12 hours, and their mutual ratio was greatly different from that after injection of AN. The results revealed that the urinary excretion of thioethers is a very sensitive and dose-related indicator of exposure to AN and extrapolation of the results indicates that the exposure to AN concentration below 10 mg X m-3 could thus be demonstrated.     

Genome Sequence of Staphylococcus epidermidis Strain AU12-03, Isolated from an Intravascular Catheter

In recent years, Staphylococcus epidermidis has become a major nosocomial pathogen and the most common cause of intravascular catheter-related bacteremia, which can increase morbidity and mortality and significantly affect patient recovery. We report a draft genome sequence of Staphylococcus epidermidis AU12-03, isolated from an intravascular catheter tip.     

Genome-wide analysis of the SET DOMAIN GROUP family in grapevine

The SET DOMAIN GROUP (SDG) proteins represent an evolutionarily-conserved family of epigenetic regulators present in eukaryotes and are putative candidates for the catalysis of lysine methylation in histones. Plant genomes analyses of this family have been performed in arabidopsis, maize, and rice and functional studies have shown that SDG genes are involved in the control of plant development. In this work, we describe the identification and structural characterization of SDG genes in the Vitis vinifera genome. This analysis revealed the presence of 33 putative SDG genes that can be grouped into different classes, as it has been previously described for plants. In addition to the SET domain, the proteins identified possessed other domains in the different classes. As part of our study regarding the growth and development of grapevine, we selected eight genes and their expression levels were analyzed in representative vegetative and reproductive organs of this species. The selected genes showed different patterns of expression during inflorescence and fruit development, suggesting that they participate in these processes. Furthermore, we showed that the expression of selected SDGs changes during viral infection, using as a model Grapevine Leafroll Associated Virus 3-infected symptomatic grapevine leaves and fruits. Our results suggest that developmental changes caused by this virus could be the result of alterations in SDG expression.