Composition and Variation of the Human Milk Microbiota Are Influenced by Maternal and Early-Life Factors

1. Download high-res image (199KB)
2. Download full-size image

     

Proximodistal Organization of the CA2 Hippocampal Area

1. Download high-res image (161KB)
2. Download full-size image

     

Reclassification of aortic stenosis by fusion of echocardiography and computed tomography in low-gradient aortic stenosis

Netherlands Heart Journal - The integration of computed tomography (CT)-derived left ventricular outflow tract area into the echocardiography-derived continuity equation results in the...     

Silicon fertigation with appropriate source reduces water requirement of maize under water deficit

Plant and Soil - The objective was to evaluate soluble sources of silicon (Si) applied through fertigation in mitigating water deficit in maize plants. Another objective was to determine the...     

Coupling of GABA Metabolism to Mitochondrial Glucose Phosphorylation

Neurochemical Research - Glucose and oxygen (O2) are vital to the brain. Glucose metabolism and mitochondria play a pivotal role in this process, culminating in the increase of reactive O2 species....     

Mating system in a small pelagic spawner: field case study of the mandarinfish,Synchiropus splendidus

Environmental Biology of Fishes - Mating systems in fishes are extremely diverse, ranging from monogamy to multiple polygamous forms, some of which include alternative male mating tactics within...     

Both human and soya bean ferritins highly improve the accumulation of bioavailable iron and contribute to extend the chronological life in budding yeast

Ferritin proteins have an enormous capacity to store iron in cells. In search for the best conditions to accumulate and store bioavailable iron, we made use of a double mutant null for the monothiol glutaredoxins GRX3 and GRX4. The strain grx3grx4 accumulates high iron concentrations in the cytoplasm, making the metal easily available for ferritin chelation. Here, we perform a comparative study between human (L and H) and soya bean ferritins (H1 and H2) function in the eukaryotic system Saccharomyces cerevisiae. We demonstrate that the four human and soya bean ferritin chains are successfully expressed in our model system. Upon coexpression of either both human or soya bean ferritin chains, respiratory conditions along with iron supplementation led us to obtain the maximum yields of iron stored in yeast described to date. Human and soya bean ferritin chains are functional and present equivalent properties as promoters of cell survival in iron overload conditions. The best system revealed that the four human and soya bean ferritins possess a novel function as anti-ageing proteins in conditions of iron excess. In this respect, both ferritin chains with oxidoreductase capacity (human-H and soya bean-H2) bear the highest capacity to extend life suggesting the possibility of an evolutionary conservation.     

Corynebacterium diphtheriae putative tellurite-resistance protein (CDCE8392_0813) contributes to the intracellular survival in human epithelial cells and lethality of Caenorhabditis elegans

Corynebacterium diphtheriae, the aetiologic agent of diphtheria, also represents a global medical challenge because of the existence of invasive strains as causative agents of systemic infections. Although tellurite (TeO3^2-) is toxic to most microorganisms, TeO3^2--resistant bacteria, including C. diphtheriae, exist in nature. The presence of TeO3^2--resistance (Te^R) determinants in pathogenic bacteria might provide selective advantages in the natural environment. In the present study, we investigated the role of the putative Te^R determinant (CDCE8392_813gene) in the virulence attributes of diphtheria bacilli. The disruption of CDCE8392_0813 gene expression in the LDCIC-L1 mutant increased susceptibility to TeO3^2- and reactive oxygen species (hydrogen peroxide), but not to other antimicrobial agents. The LDCIC-L1 mutant also showed a decrease in both the lethality of Caenorhabditis elegans and the survival inside of human epithelial cells compared to wild-type strain. Conversely, the haemagglutinating activity and adherence to and formation of biofilms on different abiotic surfaces were not regulated through the CDCE8392_0813 gene. In conclusion, the CDCE8392_813 gene contributes to the Te^R and pathogenic potential of C. diphtheriae.     

Mechanisms of growth inhibition of Phytomonas serpens by the alkaloids tomatine and tomatidine

Phytomonas serpens are flagellates in the family Trypanosomatidae that parasitise the tomato plant (Solanum lycopersicum L.), which results in fruits with low commercial value. The tomato glycoalkaloid tomatine and its aglycone tomatidine inhibit the growth of P. serpens in axenic cultures. Tomatine, like many other saponins, induces permeabilisation of the cell membrane and a loss of cell content, including the cytosolic enzyme pyruvate kinase. In contrast, tomatidine does not cause permeabilisation of membranes, but instead provokes morphological changes, including vacuolisation. Phytomonas treated with tomatidine show an increased accumulation of labelled neutral lipids (BODYPY-palmitic), a notable decrease in the amount of C₂₄-alkylated sterols and an increase in zymosterol content. These results are consistent with the inhibition of 24-sterol methyltransferase (SMT), which is an important enzyme that is responsible for the methylation of sterols at the 24 position. We propose that the main target of tomatidine is the sterols biosynthetic pathway, specifically, inhibition of the 24-SMT. Altogether, the results obtained in the present paper suggest a more general effect of alkaloids in trypanosomatids, which opens potential therapeutic possibilities for the treatment of the diseases caused by these pathogens.