Varias especies habitan en aguas salobres y estuarios y unos pocos linajes forman parte del plancton marino. Viven en los sedimentos o nadando en la columna de agua. Normalmente el flagelo emergente presenta una fila de mastigonemas. Puede aparecer un estigma o mancha ocular , con un fotorreceptor sensible a luz. Cuando las condiciones no son favorables se enquistan y germinan cuando vuelven a serlo. Algunas cepas de Euglena gracilis son utilizadas como indicadoras de vitamina B 12 en el medio.
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Exploring the glycans of Euglena gracilis. Previous work has shown that Euglena expresses a wide range of carbohydrate-active enzymes, Given the prospects for using Euglena algae as part of the biological systems of human life support in long-term space flights, we studied the effects of low doses of radiation and genotype influence on the radiosensitivity of Euglena cells.
Its chloroplastless derivate OFL strain shows increased radiosensitivity. The E. Irradiation up to 10 Gy had the hormesis effect on the initial strains, and it is only above Gy that cell death was observed. The hormesis effect was observed concerning both radioresistance and growth rate. The use of methylen blue and fluorochrome dyes allows a rapid estimation of the share of the living and dead cells. A comparison of two survival rate tests shows that the classical method of plating on a growth medium yields an increased death rate because this method does not take into account the living non-dividing cells.
Effects of Euglena Euglena gracilis supplemented to diet forage: concentrate ratios of on the basic ruminal fermentation and methane emissions in in vitro condition. An in vitro study was conducted to investigate the effect of different concentrations of Euglena Euglena gracilis on CH4 production, dry matter DM digestibility, volatile fatty acid VFA and ammonia N NH3-N concentration as well as on the protozoa population.
The treatments considered were Euglena at concentrations of 0. Euglena mitochondria and chloroplasts form tyrosine-O-sulfate. Mitochondria from light-grown wild-type Euglena gracilis var. Since no tyrosine need be added, tyrosine is provided from endogenous sources. Although TOS is found in the free pool of Euglena cells it cannot be detected in proteins of cells or mucus ruling our sulfation of tyrosine of protein or incorporation of TOS into proteins.
The system forming TOS is membrane-bound and may be involved in tyrosine transport. Gravitaxis of Euglena gracilis depends only partially on passive buoyancy. In darkness, the unicellular freshwater flagellate Euglena gracilis shows a pronounced negative gravitactic behavior, and the cells swim actively upward in the water column. Up to now it was unclear whether this behavior is based on a passive physical alignment mechanism e.
A sounding rocket experiment was performed in which the effect of sub-1g-accelerations 0. By means of computerized image analysis the angles of the cells long axis with respect to the acceleration vector were analyzed in order to calculate and compare the reorientation kinetics of the immobilized cells versus that of the controls. In both groups, the reorientation kinetics depended on the dose, but the reorientation of the living cells was about five times faster than that of the immobilized cells.
This indicates that in young cells gravitaxis can be explained by a physical mechanism only to a small extend. In addition to these results, Euglena gracilis cells seem to respond very sensitively to small accelerations when they are applied after a longer microgravity period. The data indicate that gravitactic orientation occurred at an acceleration as low as 0. Speciation of bioaccumulated uranium VI by Euglena mutabilis cells obtained by laser fluorescence spectroscopy.
Dresden Germany. It was found that axenic cultures of Euglena mutabilis Schmitz were able to bioaccumulate in 5 days The speciation of uranium in solution and uranium bioaccumulated by Euglena mutabilis cells, were studied by laser induced fluorescence spectroscopy LIFS.
Reduced uranium immobilization rates of 0. These lower rates were attributed to competition with other cations for available sorption sites. The results indicate that Euglena mutabilis has the potential to immobilize aqueous uranium under acid condition and thus may be used in future as promising agent for immobilizing uranium in low pH waste water environments. The ability of Euglena mutabilis cells - a unicellular protozoan with a flexible pellicle, which is typically found in acid mine drainage AMD environments - to bioaccumulate uranium under acid conditions was studied in batch sorption experiments at pH 3 and 4 using Na 2 SO 4 and NaClO 4 as background media.
Additional LIFS measurements, however, showed that the speciation of the bioaccumulated uranium by the Euglena mutabilis cells was found to be identical with the uranium speciation found in the bioaccumulation experiments carried out in Na 2 SO 4 and NaClO 4 media.
Full text: It is reported that the non-reducing disaccharide trehalose is accumulated in various organisms and protects biomolecules against various environmental stresses including heat shock, osmotic shock, and oxidative stresses. Euglena Euglena gracilis is photosynthetic unicellular organisms which is classified both as animal and as plant because of its motility. In our previous study, it was shown that salt stress causes degradation of paramylon, the reserve carbohydrate of Euglena , and trehalose, the degraded product of paramylon, accumulated simultaneously to maintain the osmotic pressure of Euglena cells.
Euglena is known to be radiation-resistant more than Escherichia coli and other bacteria. Therefore, we have investigated whether or not the same phenomenon could be observed in Euglena after 60 Co-gamma irradiation.
Exposure of the native Z strain and chloroplast-deficient SM-ZK strain of Euglena to a dose of kGy induced significant paramylon degradation and trehalose accumulation during the incubation in the Koren-Hunter culture medium containing glucose as carbon source after the irradiation. Forty percent of the paramylon was degraded within hr incubation after the irradiation but accumulated trehalose content was about one sixth of that by salt stress.
Trehlose accumulation disappeared when the irradiated cells were incubated in phosphate buffer but it recovered when glucose is added to the buffer to the same concentration as K-H media. These results suggest that trehalose accumulation in irradiated Euglena cells plays a role in protecting cellular constituents from oxidative damage caused by gamma-irradiation independently of the response to salt stress.
Physiological characterization of gravitaxis in Euglena gracilis and Astasia longa studied on sounding rocket flights. Euglena gracilis is a photosynthetic, unicellular flagellate found in eutrophic freshwater habitats. The organisms control their vertical position in the water column using gravi- and phototaxis.
Recent experiments demonstrated that negative gravitaxis cannot be explained by passive buoyancy but by an active physiological mechanism. During space experiments, the threshold of gravitaxis was determined to be between 0. Changes in the membrane potential and the cAMP concentration are most likely subsequent elements in a signal transduction chain, which results in reorientation strokes of the flagellum. Published by Elsevier Science Ltd.
All rights reserved. Assessment of the phytochemical constituents and antioxidant activity of a bloom forming microalgae Euglena tuba. A bloom forming algae Euglena tuba growing abundantly in the aquatic habitats of Cachar district in the state of Assam in North-East India was analysed for its phytochemical contents, antioxidant activity as well as free radical scavenging potentials.
Euglena in time: Evolution, control of central metabolic processes and multi-domain proteins in carbohydrate and natural product biochemistry. Directory of Open Access Journals Sweden. Full Text Available Euglena gracilis is a eukaryotic microalgae that has been the subject of scientific study for hundreds of years. It has a complex evolutionary history, with traces of at least four endosymbiotic genomes and extensive horizontal gene transfer. Given the importance of Euglena in terms of evolutionary cell biology and its unique taxonomic position, we initiated a de novo transcriptome sequencing project in order to understand this intriguing organism.
By analysing the proteins encoded in this transcriptome, we can identify an extremely complex metabolic capacity, rivalling that of multicellular organisms. Many genes have been acquired from what are now very distantly related species. Herein we consider the biology of Euglena in different time frames, from evolution through control of cell biology to metabolic processes associated with carbohydrate and natural products biochemistry.
Trophic transfer of gold nanoparticles from Euglena gracilis or Chlamydomonas reinhardtii to Daphnia magna. Understanding the trophic transfer of nanoparticles NPs is important because NPs are small enough to easily penetrate into organisms. We observed AuNPs transfer from 2 species of primary producers Chlamydomonas reinhardtii or Euglena gracilis to the primary consumer Daphnia magna.
Also, bioaccumulation of AuNPs in E. The reasons for the difference in Au accumulation may be the physical structure of these organisms, and the surface area that is available for interaction with NPs. The size of E. This study demonstrates the trophic transfer of AuNPs from a general producer to a consumer in an aquatic environment. On the chemical identification and visualization of uranium species in biofilms and Euglena mutabilis cells.
For risk assessment of anthropogenic uranium contaminations in the environment a detailed knowledge of the migration and immobilization behavior is required to prevent health hazards for humans and animals caused by an uncontrolled discharge of uranium.
Hence, comprehensive studies on the interactions of uranium with the environment are required. Besides the influences of the geological materials, there is a huge effect of the biosphere, especially the interactions with microorganisms and biofilms, on the properties of uranium in the environment. The aim of this study was to investigate and to describe naturally occurring biofilms from real uranium contaminated areas and their influence on the uranium migration.
The investigations in this study on the localization and the speciation of the uranium in the biosystems were primarily done with a coupled system of laser scanning microscopy CLSM and laser induced fluorescence spectroscopy LIFS.
Natural biofilms collected from two uranium contaminated acid mine drainage AMD environments, the former uranium mine in Koenigstein Saxony, Germany and the former Gessenheap near Ronneburg Thuringia,Germany , were investigated in this study.
The chosen samples represent typical biofilm communities living in AMD water and are exemplary for potentially occurring scenarios of contaminated mining water both in the underground and on the surface. The investigation on the interactions between uranium and Euglena mutabilis, which is a typical unicellular microorganism that can be found in acidic, uranium and other heavy metal containing waters, was another important part of this study.
Protein synthesis during the initial phase of the temperature-induced bleaching response in Euglena gracilis. Growing cultures of photoheterotrophic Euglena gracilis experience an increase in chlorophyll accumulation during the initial phase of the temperature-induced bleaching response suggesting an increase in the synthesis of plastid components at the bleaching temperature of 33 degree C.
A primary goal of this work was to establish whether an increase in the synthesis of plastid proteins accompanies the observed increase in chlorophyll accumulation. In vivo pulse-labeling experiments with [ 35 S]sodium sulfate were carried out with cells grown at room temperature or at 33 degree C.
The synthesis of a number of plastid polypeptides of nucleocytoplasmic origin, including some presumably novel polypeptides, increased in cultures treated for 15 hours at 33 degree C. In contrast, while synthesis of thylakoid proteins by the plastid protein synthesis machinery decreased modestly, synthesis of the large subunit of the enzyme ribulosebisphosphate carboxylase was strongly affected at the elevated temperature.
Synthesis of novel plastid-encoded polypeptides was not induced at the bleaching temperature. It is concluded that protein synthesis in plastids declines during the initial phase of the temperature response in Euglena despite an overall increase in cellular protein synthesis and an increase in chlorophyll accumulation per cell.
Low-resolution characterization of the 3D structure of the Euglena gracilis photoreceptor. This paper deals with the first characterization of the structure of the photoreceptive organelle of the unicellular alga Euglena gracilis Euglenophyta. This organelle has a three-dimensional organization consisting of up to 50 closely stacked membrane lamellae.
Ionically induced unstacking of the photoreceptor lamellae revealed ordered arrays well suited to structural analysis by electron microscopy and image analysis, which ultimately yielded a low-resolution picture of the structure. Each lamella is formed by the photoreceptive membrane protein of the cell assembled within the membrane layer in a hexagonal lattice. The first order diffraction spots in the calculated Fourier transform reveals the presence of 6-fold symmetrized topography better resolution about 90 A.
The 2D and 3D structural data are very similar with those recently published on proteorodopsin, a membrane protein used by marine bacterio-plankton as light-driven proton pump.
In our opinion these similarity indicate that a photoreceptive protein belonging to the same superfamily of proteorodopsin could form the Euglena photoreceptor. Effect of chromium on the fatty acid composition of two strains of Euglena gracilis. E-mail: rocchetta bg. Photoheterotrophic control strains exhibited a significantly higher proportion of saturated and polyunsaturated fatty acids. Polyunsaturated acids were most affected by chromium, especially those related to chloroplast structures.
Ultra-structure studies showed clear thylakoid disorganization in all treated cells.
Exploring the glycans of Euglena gracilis. Previous work has shown that Euglena expresses a wide range of carbohydrate-active enzymes, Given the prospects for using Euglena algae as part of the biological systems of human life support in long-term space flights, we studied the effects of low doses of radiation and genotype influence on the radiosensitivity of Euglena cells. Its chloroplastless derivate OFL strain shows increased radiosensitivity. The E. Irradiation up to 10 Gy had the hormesis effect on the initial strains, and it is only above Gy that cell death was observed. The hormesis effect was observed concerning both radioresistance and growth rate.