Search results for "Acte"
showing 10 items of 9295 documents
Birth Mode-Related Differences in Gut Microbiota Colonization and Immune System Development.
2018
<b><i>Background:</i></b> The process of early gut colonization is extremely variable among individuals and is influenced by numerous factors. Among these, the mode of birth will strongly shape the early microbial exposure and immune environment of the neonate. <b><i>Summary:</i></b> Here, I review how the concomitant processes of microbiota and immune system development are altered by C-section delivery and the effects of such alterations on long-term health. <b><i>Key messages:</i></b> C-section delivery impinges on microbiota and immune system development through various means: (i) if labor is lacking, intrauterine i…
Light-induced structural changes in a monomeric bacteriophytochrome
2016
International audience; Phytochromes sense red light in plants and various microorganism. Light absorption causes structural changes within the protein, which alter its biochemical activity. Bacterial phytochromes are dimeric proteins, but the functional relevance of this arrangement remains unclear. Here, we use time-resolved X-ray scattering to reveal the solution structural change of a monomeric variant of the photosensory core module of the phytochrome from Deinococcus radiodurans. The data reveal two motions, a bend and a twist of the PHY domain with respect to the chromophore-binding domains. Infrared spectroscopy shows the refolding of the PHY tongue. We conclude that a monomer of th…
Simultaneous infection of cattle with different Anaplasma phagocytophilum variants.
2019
Anaplasma phagocytophilum is a tick-transmitted Gram-negative obligate intracellular bacterium that replicates in neutrophil granulocytes. It causes tick-borne fever in cattle and sheep. We report here the case of a 5-year-old cow from Germany with clinically overt granulocytic anaplasmosis presenting with fever, lower limb oedema and drop in milk-yield. The herd encompassed 10 animals, 8 other animals showed subclinical infection. The strains from the 9 A. phagocytophilum positive cows were molecularly characterized using ankA gene-based and multilocus sequence typing (MLST). Seven of 9 (78%) animals were infected simultaneously with different ankA variants belonging to ankA clusters I and…
Assessment of the Antimicrobial Activity and the Entomocidal Potential of Bacillus thuringiensis Isolates from Algeria.
2017
This work represents the first initiative to analyze the distribution of B. thuringiensis in Algeria and to evaluate the biological potential of the isolates. A total of 157 isolates were recovered, with at least one isolate in 94.4% of the samples. The highest Bt index was found in samples from rhizospheric soil (0.48) and from the Mediterranean area (0.44). Most isolates showed antifungal activity (98.5%), in contrast to the few that had antibacterial activity (29.9%). A high genetic diversity was made evident by the finding of many different crystal shapes and various combinations of shapes within a single isolate (in 58.4% of the isolates). Also, over 50% of the isolates harbored cry1, …
Pleomorphic forms of Borrelia burgdorferi induce distinct immune responses.
2016
Borrelia burgdorferi is the causative agent of tick-borne Lyme disease. As a response to environmental stress B. burgdorferi can change its morphology to a round body form. The role of B. burgdorferi pleomorphic forms in Lyme disease pathogenesis has long been debated and unclear. Here, we demonstrated that round bodies were processed differently in differentiated macrophages, consequently inducing distinct immune responses compared to spirochetes in vitro. Colocalization analysis indicated that the F-actin participates in internalization of both forms. However, round bodies end up less in macrophage lysosomes than spirochetes suggesting that there are differences in processing of these for…
Impact of Fermentation on the Recovery of Antioxidant Bioactive Compounds from Sea Bass Byproducts
2020
The aim of the present research was to obtain antioxidant compounds through the fermentation of fish byproducts by bacteria isolated from sea bass viscera. To that purpose, bacteria from sea bass stomach, intestine, and colon were isolated. With the selected bacteria, growing research was undertaken, fermenting different broths prepared with sea bass meat or byproducts. After the fermentation, the antioxidant activity, phenolic acids, and some proteins were evaluated. The main phenolic acids obtained were DL-3-phenyl-lactic acid and benzoic acid at a maximum concentration of 466 and 314 ppb, respectively. The best antioxidant activity was found in the extracts obtained after the fermentatio…
Anticancer, antioxidant, and antibacterial activities of low molecular weight bioactive subfractions isolated from cultures of wood degrading fungus …
2017
The aim of this study is to investigate in vitro the anticancer, antioxidant, and antibacterial activities of three low molecular weight subfractions I, II and III isolated from secondary metabolites produced by the wood degrading fungus Cerrena unicolor. The present study demonstrated that the low molecular weight subfractions III exhibited the strongest inhibitory activity towards breast carcinoma cells MDA-MB-231, prostatic carcinoma cells PC3, and breast cancer cells MCF7 with the half-maximal inhibitory concentration (IC50) value of 52,25 μg/mL, 60,66 μg/mL, and 54,92 μg/mL, respectively. The highest percentage of inhibition was noted at a concentration of 300 μg/mL in all the examined…
In vitro effects of Origanum vulgare leaf extracts on gilthead seabream (Sparus aurata L.) leucocytes, cytotoxic, bactericidal and antioxidant activi…
2018
Abstract Origanum vulgare is a well-known medicinal plant that has been used since ancient times as an additive in foods and cosmetic preparations. The possible application of O. vulgare extracts in fish was assessed by using gilthead seabream (Sparus aurata) as a marine fish model due to its importance in aquaculture. The in vitro effects of aqueous and ethanolic leaf extracts of O. vulgare were tested in order to observe any immunostimulant, cytotoxic, bactericidal or antioxidant properties. The results showed that medium or high concentration of aqueous extracts and low concentrations of ethanolic extract, increased head kidney leucocyte activities as well as the number of SAF-1 cells. H…
Chemical–physical characteristics, polyphenolic content and total antioxidant activity of three Italian-grown pomegranate cultivars
2019
Background: In Mediterranean countries, there is an increasing demand for pomegranate fruits due to their antioxidant properties and nutritional values. The large diffusion of new genotypes and cultivars requires the knowledge of all fruit characteristics in connection with the cultivation area, to satisfy the market demand. This study seeks to determine the fruit quality attributes and nutraceutical values of three pomegranate cultivars (Wonderful, Acco and Kamel) grown in the Mediterranean climate. Methods: The fruits were evaluated for their main physico-chemical traits (weight, volume, height, width, thickness, total arils number, total arils weight, juiciness, fruit index, peel index a…
Contribution of aerobic anoxygenic phototrophic bacteria to total organic carbon pool in aquatic system of subtropical karst catchments, Southwest Ch…
2017
Aerobic anoxygenic phototrophic bacteria may play a particular role in carbon cycling of aquatic systems. However, little is known about the interaction between aerobic anoxygenic phototrophic bacteria and hydrochemistry in groundwater-surface water exchange systems of subtropical karst catchments. We carried out a detailed study on the abundance of aerobic anoxygenic phototrophic bacteria and bacterioplankton, hydrochemistry and taxonomy of bacterioplankton in the Maocun watershed, Southwest China, an area with karst geological background. Our results revealed that bacteria are the important contributors to total organic carbon source/sequestration in the groundwater-surface water of this …